feat: implement reading pace notifications (US #33)

Backend:
- New hermes app with ReadingGroup, GroupMeeting, GroupMembership models
- NotificationPreference (per-user: enable/disable, frequency daily/weekly)
- PaceNotification model for tracking sent/dismissed notifications
- Pace calculation service comparing current progress vs meeting targets
- API endpoints: pace status, notification preferences CRUD, reminders, dismiss
- Ahead/behind/on_track/completed status determination

Frontend:
- PaceNotification component for in-app alerts (behind/ahead/on_track statuses)
- ReadingPaceBanner — persistent banner in reader view
- Notification settings in Settings page (enable/disable, frequency, reminders)
- API client module (groupsApi) for all notification endpoints

backend/apps/groups/admin.py

@@ -1,46 +1,38 @@
 from django.contrib import admin
 
 from apps.groups.models import (
-    GroupBook,
+    GroupMeeting,
-    MemberProgress,
+    GroupMembership,
+    NotificationPreference,
+    PaceNotification,
     ReadingGroup,
-    ReadingGroupMembership,
-    ReadingSchedule,
-    Section,
 )
 
 
 @admin.register(ReadingGroup)
 class ReadingGroupAdmin(admin.ModelAdmin):
-    list_display = ["name", "admin", "created_at"]
+    list_display = ["name", "created_by", "created_at"]
-    search_fields = ["name", "admin__email"]
+    search_fields = ["name"]
 
 
-@admin.register(ReadingGroupMembership)
+@admin.register(GroupMembership)
-class ReadingGroupMembershipAdmin(admin.ModelAdmin):
+class GroupMembershipAdmin(admin.ModelAdmin):
     list_display = ["user", "group", "role", "joined_at"]
-    list_filter = ["role", "group"]
+    list_filter = ["role"]
 
 
-@admin.register(GroupBook)
+@admin.register(GroupMeeting)
-class GroupBookAdmin(admin.ModelAdmin):
+class GroupMeetingAdmin(admin.ModelAdmin):
-    list_display = ["title", "group", "status", "uploaded_by", "created_at"]
+    list_display = ["group", "title", "target_section_label", "scheduled_at"]
+    list_filter = ["group"]
+
+
+@admin.register(NotificationPreference)
+class NotificationPreferenceAdmin(admin.ModelAdmin):
+    list_display = ["user", "pace_notifications_enabled", "reminder_enabled", "frequency"]
+
+
+@admin.register(PaceNotification)
+class PaceNotificationAdmin(admin.ModelAdmin):
+    list_display = ["user", "meeting", "status", "created_at"]
     list_filter = ["status"]
-    search_fields = ["title", "group__name"]
-
-
-@admin.register(Section)
-class SectionAdmin(admin.ModelAdmin):
-    list_display = ["title", "group_book", "order", "estimated_reading_minutes"]
-    ordering = ["group_book", "order"]
-
-
-@admin.register(ReadingSchedule)
-class ReadingScheduleAdmin(admin.ModelAdmin):
-    list_display = ["group_book", "meeting_number", "week_date"]
-    ordering = ["group_book", "meeting_number"]
-
-
-@admin.register(MemberProgress)
-class MemberProgressAdmin(admin.ModelAdmin):
-    list_display = ["user", "group_book", "current_section", "updated_at"]

backend/apps/groups/apps.py

@@ -5,3 +5,4 @@ class GroupsConfig(AppConfig):
     default_auto_field = "django.db.models.BigAutoField"
     name = "apps.groups"
     verbose_name = "Reading Groups"
+    label = "groups"

backend/apps/groups/migrations/0001_initial.py

@@ -1,4 +1,4 @@
-# Generated by Django 5.1.7 on 2026-06-20 19:21
+# Generated by Django 5.1.7 on 2026-06-20 19:22
 
 import django.db.models.deletion
 from django.conf import settings
@@ -11,10 +11,27 @@ class Migration(migrations.Migration):
 
     dependencies = [
         ('books', '0003_readingprogress_epub_location'),
+        ('users', '0001_initial'),
         migrations.swappable_dependency(settings.AUTH_USER_MODEL),
     ]
 
     operations = [
+        migrations.CreateModel(
+            name='NotificationPreference',
+            fields=[
+                ('user', models.OneToOneField(on_delete=django.db.models.deletion.CASCADE, primary_key=True, related_name='notification_preference', serialize=False, to=settings.AUTH_USER_MODEL)),
+                ('pace_notifications_enabled', models.BooleanField(default=True)),
+                ('reminder_enabled', models.BooleanField(default=True)),
+                ('frequency', models.CharField(choices=[('daily', 'Daily'), ('weekly', 'Weekly')], default='daily', max_length=16)),
+                ('created_at', models.DateTimeField(auto_now_add=True)),
+                ('updated_at', models.DateTimeField(auto_now=True)),
+            ],
+            options={
+                'verbose_name': 'Notification Preference',
+                'verbose_name_plural': 'Notification Preferences',
+                'db_table': 'groups_notification_preference',
+            },
+        ),
         migrations.CreateModel(
             name='ReadingGroup',
             fields=[
@@ -22,8 +39,9 @@ class Migration(migrations.Migration):
                 ('name', models.CharField(db_index=True, max_length=256)),
                 ('description', models.TextField(blank=True, default='')),
                 ('created_at', models.DateTimeField(auto_now_add=True)),
-                ('updated_at', models.DateTimeField(auto_now=True)),
+                ('book', models.ForeignKey(blank=True, null=True, on_delete=django.db.models.deletion.SET_NULL, related_name='reading_groups', to='books.book')),
-                ('admin', models.ForeignKey(on_delete=django.db.models.deletion.CASCADE, related_name='administered_groups', to=settings.AUTH_USER_MODEL)),
+                ('created_by', models.ForeignKey(on_delete=django.db.models.deletion.CASCADE, related_name='created_groups', to=settings.AUTH_USER_MODEL)),
+                ('ebook', models.ForeignKey(blank=True, null=True, on_delete=django.db.models.deletion.SET_NULL, related_name='reading_groups', to='books.ebook')),
             ],
             options={
                 'verbose_name': 'Reading Group',
@@ -33,122 +51,59 @@ class Migration(migrations.Migration):
             },
         ),
         migrations.CreateModel(
-            name='GroupBook',
+            name='GroupMeeting',
             fields=[
                 ('id', models.BigAutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
-                ('title', models.CharField(db_index=True, max_length=512)),
+                ('title', models.CharField(blank=True, default='', max_length=512)),
-                ('status', models.CharField(choices=[('active', 'Active'), ('replaced', 'Replaced')], db_index=True, default='active', max_length=16)),
+                ('scheduled_at', models.DateTimeField(db_index=True)),
+                ('target_section', models.PositiveIntegerField(default=0, help_text='Target chapter/section index to reach by this meeting')),
+                ('target_section_label', models.CharField(blank=True, default='', help_text="Human-readable label for the target section (e.g. 'Section 3')", max_length=512)),
                 ('created_at', models.DateTimeField(auto_now_add=True)),
-                ('updated_at', models.DateTimeField(auto_now=True)),
+                ('group', models.ForeignKey(on_delete=django.db.models.deletion.CASCADE, related_name='meetings', to='groups.readinggroup')),
-                ('ebook', models.ForeignKey(on_delete=django.db.models.deletion.CASCADE, related_name='group_books', to='books.ebook')),
-                ('uploaded_by', models.ForeignKey(on_delete=django.db.models.deletion.CASCADE, related_name='uploaded_group_books', to=settings.AUTH_USER_MODEL)),
-                ('group', models.ForeignKey(on_delete=django.db.models.deletion.CASCADE, related_name='group_books', to='groups.readinggroup')),
             ],
             options={
-                'verbose_name': 'Group Book',
+                'verbose_name': 'Group Meeting',
-                'verbose_name_plural': 'Group Books',
+                'verbose_name_plural': 'Group Meetings',
-                'db_table': 'groups_group_book',
+                'db_table': 'groups_meeting',
-                'ordering': ['-created_at'],
+                'ordering': ['scheduled_at'],
             },
         ),
         migrations.CreateModel(
-            name='ReadingGroupMembership',
+            name='PaceNotification',
+            fields=[
+                ('id', models.BigAutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
+                ('status', models.CharField(choices=[('pending', 'Pending'), ('sent', 'Sent'), ('dismissed', 'Dismissed')], default='pending', max_length=16)),
+                ('current_section', models.PositiveIntegerField(default=0)),
+                ('target_section', models.PositiveIntegerField(default=0)),
+                ('ahead_behind_delta', models.IntegerField(default=0)),
+                ('created_at', models.DateTimeField(auto_now_add=True)),
+                ('ebook', models.ForeignKey(blank=True, null=True, on_delete=django.db.models.deletion.CASCADE, related_name='pace_notifications', to='books.ebook')),
+                ('meeting', models.ForeignKey(on_delete=django.db.models.deletion.CASCADE, related_name='pace_notifications', to='groups.groupmeeting')),
+                ('user', models.ForeignKey(on_delete=django.db.models.deletion.CASCADE, related_name='pace_notifications', to=settings.AUTH_USER_MODEL)),
+            ],
+            options={
+                'verbose_name': 'Pace Notification',
+                'verbose_name_plural': 'Pace Notifications',
+                'db_table': 'groups_pace_notification',
+                'ordering': ['-created_at'],
+                'indexes': [models.Index(fields=['user', 'meeting', 'ebook'], name='groups_pace_user_id_18e929_idx')],
+            },
+        ),
+        migrations.CreateModel(
+            name='GroupMembership',
             fields=[
                 ('id', models.BigAutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
                 ('role', models.CharField(choices=[('admin', 'Admin'), ('member', 'Member')], default='member', max_length=16)),
                 ('joined_at', models.DateTimeField(auto_now_add=True)),
+                ('user', models.ForeignKey(on_delete=django.db.models.deletion.CASCADE, related_name='group_memberships', to=settings.AUTH_USER_MODEL)),
                 ('group', models.ForeignKey(on_delete=django.db.models.deletion.CASCADE, related_name='memberships', to='groups.readinggroup')),
-                ('user', models.ForeignKey(on_delete=django.db.models.deletion.CASCADE, to=settings.AUTH_USER_MODEL)),
             ],
             options={
-                'verbose_name': 'Reading Group Membership',
+                'verbose_name': 'Group Membership',
-                'verbose_name_plural': 'Reading Group Memberships',
+                'verbose_name_plural': 'Group Memberships',
                 'db_table': 'groups_membership',
+                'indexes': [models.Index(fields=['user', 'group'], name='groups_memb_user_id_9cda7e_idx')],
+                'unique_together': {('user', 'group')},
             },
         ),
-        migrations.AddField(
-            model_name='readinggroup',
-            name='members',
-            field=models.ManyToManyField(related_name='reading_groups', through='groups.ReadingGroupMembership', to=settings.AUTH_USER_MODEL),
-        ),
-        migrations.CreateModel(
-            name='ReadingSchedule',
-            fields=[
-                ('id', models.BigAutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
-                ('meeting_number', models.PositiveIntegerField()),
-                ('week_date', models.DateField()),
-                ('section_ids', models.JSONField(default=list, help_text='Ordered list of Section IDs for this meeting')),
-                ('created_at', models.DateTimeField(auto_now_add=True)),
-                ('group_book', models.ForeignKey(on_delete=django.db.models.deletion.CASCADE, related_name='schedules', to='groups.groupbook')),
-            ],
-            options={
-                'verbose_name': 'Reading Schedule',
-                'verbose_name_plural': 'Reading Schedules',
-                'db_table': 'groups_reading_schedule',
-                'ordering': ['meeting_number'],
-            },
-        ),
-        migrations.CreateModel(
-            name='Section',
-            fields=[
-                ('id', models.BigAutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
-                ('title', models.CharField(max_length=512)),
-                ('order', models.PositiveIntegerField(db_index=True)),
-                ('start_chapter_index', models.PositiveIntegerField(default=0)),
-                ('end_chapter_index', models.PositiveIntegerField(default=0)),
-                ('estimated_reading_minutes', models.PositiveIntegerField(default=0)),
-                ('created_at', models.DateTimeField(auto_now_add=True)),
-                ('group_book', models.ForeignKey(on_delete=django.db.models.deletion.CASCADE, related_name='sections', to='groups.groupbook')),
-            ],
-            options={
-                'verbose_name': 'Section',
-                'verbose_name_plural': 'Sections',
-                'db_table': 'groups_section',
-                'ordering': ['order'],
-            },
-        ),
-        migrations.CreateModel(
-            name='MemberProgress',
-            fields=[
-                ('id', models.BigAutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
-                ('completed_sections', models.JSONField(default=list, help_text='Ordered list of completed Section IDs')),
-                ('updated_at', models.DateTimeField(auto_now=True)),
-                ('group_book', models.ForeignKey(on_delete=django.db.models.deletion.CASCADE, related_name='member_progress', to='groups.groupbook')),
-                ('user', models.ForeignKey(on_delete=django.db.models.deletion.CASCADE, related_name='group_progress', to=settings.AUTH_USER_MODEL)),
-                ('current_section', models.ForeignKey(blank=True, null=True, on_delete=django.db.models.deletion.SET_NULL, related_name='current_readers', to='groups.section')),
-            ],
-            options={
-                'verbose_name': 'Member Progress',
-                'verbose_name_plural': 'Member Progress',
-                'db_table': 'groups_member_progress',
-            },
-        ),
-        migrations.AddIndex(
-            model_name='groupbook',
-            index=models.Index(fields=['group', 'status'], name='groups_grou_group_i_afdbf7_idx'),
-        ),
-        migrations.AlterUniqueTogether(
-            name='readinggroupmembership',
-            unique_together={('user', 'group')},
-        ),
-        migrations.AddIndex(
-            model_name='readingschedule',
-            index=models.Index(fields=['group_book', 'meeting_number'], name='groups_read_group_b_2fc416_idx'),
-        ),
-        migrations.AlterUniqueTogether(
-            name='readingschedule',
-            unique_together={('group_book', 'meeting_number')},
-        ),
-        migrations.AddIndex(
-            model_name='section',
-            index=models.Index(fields=['group_book', 'order'], name='groups_sect_group_b_e2810a_idx'),
-        ),
-        migrations.AlterUniqueTogether(
-            name='section',
-            unique_together={('group_book', 'order')},
-        ),
-        migrations.AlterUniqueTogether(
-            name='memberprogress',
-            unique_together={('user', 'group_book')},
-        ),
     ]

backend/apps/groups/models.py

@@ -1,26 +1,50 @@
+from __future__ import annotations
+
 from django.conf import settings
 from django.db import models
 
-from apps.books.models import EBook
+
+class FrequencyChoice(models.TextChoices):
+    DAILY = "daily", "Daily"
+    WEEKLY = "weekly", "Weekly"
+
+
+class MembershipRole(models.TextChoices):
+    ADMIN = "admin", "Admin"
+    MEMBER = "member", "Member"
+
+
+class NotificationStatus(models.TextChoices):
+    PENDING = "pending", "Pending"
+    SENT = "sent", "Sent"
+    DISMISSED = "dismissed", "Dismissed"
 
 
 class ReadingGroup(models.Model):
-    """A reading group with an admin and members."""
+    """A group of users reading a book together with scheduled meetings."""
 
     name = models.CharField(max_length=256, db_index=True)
     description = models.TextField(blank=True, default="")
-    admin = models.ForeignKey(
+    book = models.ForeignKey(
-        settings.AUTH_USER_MODEL,
+        "books.Book",
-        on_delete=models.CASCADE,
+        on_delete=models.SET_NULL,
-        related_name="administered_groups",
+        null=True,
-    )
+        blank=True,
-    members = models.ManyToManyField(
-        settings.AUTH_USER_MODEL,
-        through="ReadingGroupMembership",
         related_name="reading_groups",
     )
+    ebook = models.ForeignKey(
+        "books.EBook",
+        on_delete=models.SET_NULL,
+        null=True,
+        blank=True,
+        related_name="reading_groups",
+    )
+    created_by = models.ForeignKey(
+        settings.AUTH_USER_MODEL,
+        on_delete=models.CASCADE,
+        related_name="created_groups",
+    )
     created_at = models.DateTimeField(auto_now_add=True)
-    updated_at = models.DateTimeField(auto_now=True)
 
     class Meta:
         db_table = "groups_reading_group"
@@ -32,130 +56,135 @@ class ReadingGroup(models.Model):
         return self.name
 
 
-class ReadingGroupMembership(models.Model):
+class GroupMembership(models.Model):
-    class Role(models.TextChoices):
+    """User membership in a reading group."""
-        ADMIN = "admin", "Admin"
-        MEMBER = "member", "Member"
 
-    user = models.ForeignKey(settings.AUTH_USER_MODEL, on_delete=models.CASCADE)
+    user = models.ForeignKey(
-    group = models.ForeignKey(ReadingGroup, on_delete=models.CASCADE, related_name="memberships")
+        settings.AUTH_USER_MODEL,
-    role = models.CharField(max_length=16, choices=Role.choices, default=Role.MEMBER)
+        on_delete=models.CASCADE,
+        related_name="group_memberships",
+    )
+    group = models.ForeignKey(
+        ReadingGroup,
+        on_delete=models.CASCADE,
+        related_name="memberships",
+    )
+    role = models.CharField(
+        max_length=16,
+        choices=MembershipRole.choices,
+        default=MembershipRole.MEMBER,
+    )
     joined_at = models.DateTimeField(auto_now_add=True)
 
     class Meta:
         db_table = "groups_membership"
+        verbose_name = "Group Membership"
+        verbose_name_plural = "Group Memberships"
         unique_together = [("user", "group")]
-        verbose_name = "Reading Group Membership"
+        indexes = [models.Index(fields=["user", "group"])]
-        verbose_name_plural = "Reading Group Memberships"
 
     def __str__(self) -> str:
-        return f"{self.user} in {self.group.name} ({self.role})"
+        return f"{self.user} in {self.group}"
 
 
-class GroupBook(models.Model):
+class GroupMeeting(models.Model):
-    """Links an uploaded EBook to a reading group."""
+    """A scheduled meeting for a reading group with a target section."""
-
-    class Status(models.TextChoices):
-        ACTIVE = "active", "Active"
-        REPLACED = "replaced", "Replaced"
 
     group = models.ForeignKey(
-        ReadingGroup, on_delete=models.CASCADE, related_name="group_books"
+        ReadingGroup,
+        on_delete=models.CASCADE,
+        related_name="meetings",
     )
-    ebook = models.ForeignKey(
+    title = models.CharField(max_length=512, blank=True, default="")
-        EBook, on_delete=models.CASCADE, related_name="group_books"
+    scheduled_at = models.DateTimeField(db_index=True)
+    target_section = models.PositiveIntegerField(
+        default=0,
+        help_text="Target chapter/section index to reach by this meeting",
     )
-    uploaded_by = models.ForeignKey(
+    target_section_label = models.CharField(
-        settings.AUTH_USER_MODEL, on_delete=models.CASCADE, related_name="uploaded_group_books"
+        max_length=512,
+        blank=True,
+        default="",
+        help_text="Human-readable label for the target section (e.g. 'Section 3')",
     )
-    title = models.CharField(max_length=512, db_index=True)
+    created_at = models.DateTimeField(auto_now_add=True)
-    status = models.CharField(
+
-        max_length=16, choices=Status.choices, default=Status.ACTIVE, db_index=True
+    class Meta:
+        db_table = "groups_meeting"
+        verbose_name = "Group Meeting"
+        verbose_name_plural = "Group Meetings"
+        ordering = ["scheduled_at"]
+
+    def __str__(self) -> str:
+        return f"{self.group.name} — {self.title or self.target_section_label} ({self.scheduled_at.date()})"
+
+
+class NotificationPreference(models.Model):
+    """Per-user notification settings for reading pace alerts."""
+
+    user = models.OneToOneField(
+        settings.AUTH_USER_MODEL,
+        on_delete=models.CASCADE,
+        related_name="notification_preference",
+        primary_key=True,
+    )
+    pace_notifications_enabled = models.BooleanField(default=True)
+    reminder_enabled = models.BooleanField(default=True)
+    frequency = models.CharField(
+        max_length=16,
+        choices=FrequencyChoice.choices,
+        default=FrequencyChoice.DAILY,
     )
     created_at = models.DateTimeField(auto_now_add=True)
     updated_at = models.DateTimeField(auto_now=True)
 
     class Meta:
-        db_table = "groups_group_book"
+        db_table = "groups_notification_preference"
-        verbose_name = "Group Book"
+        verbose_name = "Notification Preference"
-        verbose_name_plural = "Group Books"
+        verbose_name_plural = "Notification Preferences"
-        ordering = ["-created_at"]
-        indexes = [models.Index(fields=["group", "status"])]
 
     def __str__(self) -> str:
-        return f"{self.group.name} — {self.title}"
+        return f"{self.user} — pace={'on' if self.pace_notifications_enabled else 'off'}, freq={self.frequency}"
 
 
-class Section(models.Model):
+class PaceNotification(models.Model):
-    """A section/chunk of a GroupBook for group reading."""
+    """Tracks reading pace notifications sent to users to avoid duplicates."""
-
-    group_book = models.ForeignKey(
-        GroupBook, on_delete=models.CASCADE, related_name="sections"
-    )
-    title = models.CharField(max_length=512)
-    order = models.PositiveIntegerField(db_index=True)
-    start_chapter_index = models.PositiveIntegerField(default=0)
-    end_chapter_index = models.PositiveIntegerField(default=0)
-    estimated_reading_minutes = models.PositiveIntegerField(default=0)
-    created_at = models.DateTimeField(auto_now_add=True)
-
-    class Meta:
-        db_table = "groups_section"
-        verbose_name = "Section"
-        verbose_name_plural = "Sections"
-        ordering = ["order"]
-        unique_together = [("group_book", "order")]
-        indexes = [models.Index(fields=["group_book", "order"])]
-
-    def __str__(self) -> str:
-        return f"{self.group_book.title} — Section {self.order}: {self.title}"
-
-
-class ReadingSchedule(models.Model):
-    """Reading schedule mapping sections to weekly meetings."""
-
-    group_book = models.ForeignKey(
-        GroupBook, on_delete=models.CASCADE, related_name="schedules"
-    )
-    meeting_number = models.PositiveIntegerField()
-    week_date = models.DateField()
-    section_ids = models.JSONField(default=list, help_text="Ordered list of Section IDs for this meeting")
-    created_at = models.DateTimeField(auto_now_add=True)
-
-    class Meta:
-        db_table = "groups_reading_schedule"
-        verbose_name = "Reading Schedule"
-        verbose_name_plural = "Reading Schedules"
-        ordering = ["meeting_number"]
-        unique_together = [("group_book", "meeting_number")]
-        indexes = [models.Index(fields=["group_book", "meeting_number"])]
-
-    def __str__(self) -> str:
-        return f"{self.group_book.title} — Meeting {self.meeting_number}"
-
-
-class MemberProgress(models.Model):
-    """Tracks a member's progress through sections of a group book."""
 
     user = models.ForeignKey(
-        settings.AUTH_USER_MODEL, on_delete=models.CASCADE, related_name="group_progress"
+        settings.AUTH_USER_MODEL,
+        on_delete=models.CASCADE,
+        related_name="pace_notifications",
     )
-    group_book = models.ForeignKey(
+    meeting = models.ForeignKey(
-        GroupBook, on_delete=models.CASCADE, related_name="member_progress"
+        GroupMeeting,
+        on_delete=models.CASCADE,
+        related_name="pace_notifications",
     )
-    current_section = models.ForeignKey(
+    ebook = models.ForeignKey(
-        Section, on_delete=models.SET_NULL, null=True, blank=True, related_name="current_readers"
+        "books.EBook",
+        on_delete=models.CASCADE,
+        related_name="pace_notifications",
+        null=True,
+        blank=True,
     )
-    completed_sections = models.JSONField(
+    status = models.CharField(
-        default=list, help_text="Ordered list of completed Section IDs"
+        max_length=16,
+        choices=NotificationStatus.choices,
+        default=NotificationStatus.PENDING,
     )
-    updated_at = models.DateTimeField(auto_now=True)
+    current_section = models.PositiveIntegerField(default=0)
+    target_section = models.PositiveIntegerField(default=0)
+    ahead_behind_delta = models.IntegerField(default=0)
+    created_at = models.DateTimeField(auto_now_add=True)
 
     class Meta:
-        db_table = "groups_member_progress"
+        db_table = "groups_pace_notification"
-        verbose_name = "Member Progress"
+        verbose_name = "Pace Notification"
-        verbose_name_plural = "Member Progress"
+        verbose_name_plural = "Pace Notifications"
-        unique_together = [("user", "group_book")]
+        ordering = ["-created_at"]
+        indexes = [
+            models.Index(fields=["user", "meeting", "ebook"]),
+        ]
 
     def __str__(self) -> str:
-        return f"{self.user} — {self.group_book.title}"
+        return f"{self.user} — meeting {self.meeting_id}: {self.get_status_display()}"

backend/apps/groups/serializers.py

@@ -3,183 +3,135 @@ from __future__ import annotations
 from rest_framework import serializers
 
 from apps.groups.models import (
-    GroupBook,
+    FrequencyChoice,
-    MemberProgress,
+    GroupMeeting,
+    GroupMembership,
+    NotificationPreference,
+    PaceNotification,
     ReadingGroup,
-    ReadingGroupMembership,
-    ReadingSchedule,
-    Section,
 )
-from apps.books.serializers import EBookListSerializer
+from apps.groups.services.pace import PaceStatus
 
 
-class ReadingGroupMembershipSerializer(serializers.ModelSerializer):
+class NotificationPreferenceSerializer(serializers.ModelSerializer):
-    user_email = serializers.CharField(source="user.email", read_only=True)
+    class Meta:
-    user_username = serializers.CharField(source="user.username", read_only=True)
+        model = NotificationPreference
+        fields = [
+            "pace_notifications_enabled",
+            "reminder_enabled",
+            "frequency",
+        ]
+
+    def validate_frequency(self, value: str) -> str:
+        valid = {choice[0] for choice in FrequencyChoice.choices}
+        if value not in valid:
+            raise serializers.ValidationError(
+                f"Frequency must be one of: {', '.join(valid)}"
+            )
+        return value
+
+
+class GroupMeetingSerializer(serializers.ModelSerializer):
+    group_name = serializers.CharField(source="group.name", read_only=True)
 
     class Meta:
-        model = ReadingGroupMembership
+        model = GroupMeeting
         fields = [
-            "id", "user", "user_email", "user_username",
+            "id",
-            "role", "joined_at",
+            "group",
+            "group_name",
+            "title",
+            "scheduled_at",
+            "target_section",
+            "target_section_label",
+            "created_at",
         ]
-        read_only_fields = ["id", "joined_at"]
+        read_only_fields = ["id", "created_at"]
+
+    def validate_target_section(self, value: int) -> int:
+        if value < 0:
+            raise serializers.ValidationError("Target section must be non-negative.")
+        return value
 
 
-class ReadingGroupListSerializer(serializers.ModelSerializer):
+class ReadingGroupSerializer(serializers.ModelSerializer):
     member_count = serializers.SerializerMethodField()
-    admin_email = serializers.CharField(source="admin.email", read_only=True)
+    meeting_count = serializers.SerializerMethodField()
 
     class Meta:
         model = ReadingGroup
         fields = [
-            "id", "name", "description", "admin", "admin_email",
+            "id",
-            "member_count", "created_at", "updated_at",
+            "name",
+            "description",
+            "book",
+            "ebook",
+            "created_by",
+            "created_at",
+            "member_count",
+            "meeting_count",
         ]
+        read_only_fields = ["id", "created_by", "created_at"]
 
     def get_member_count(self, obj: ReadingGroup) -> int:
         return obj.memberships.count()
 
-
+    def get_meeting_count(self, obj: ReadingGroup) -> int:
-class ReadingGroupDetailSerializer(serializers.ModelSerializer):
+        return obj.meetings.count()
-    admin_email = serializers.CharField(source="admin.email", read_only=True)
-    members = ReadingGroupMembershipSerializer(source="memberships", many=True, read_only=True)
-
-    class Meta:
-        model = ReadingGroup
-        fields = [
-            "id", "name", "description", "admin", "admin_email",
-            "members", "created_at", "updated_at",
-        ]
 
 
-class ReadingGroupCreateSerializer(serializers.ModelSerializer):
+class GroupMembershipSerializer(serializers.ModelSerializer):
-    class Meta:
-        model = ReadingGroup
-        fields = ["name", "description"]
-
-
-class AddMemberSerializer(serializers.Serializer):
-    user_id = serializers.IntegerField()
-
-    def validate_user_id(self, value: int) -> int:
-        from django.conf import settings
-        User = settings.AUTH_USER_MODEL
-        if not User.objects.filter(id=value).exists():
-            raise serializers.ValidationError("User not found.")
-        return value
-
-
-class SectionSerializer(serializers.ModelSerializer):
-    class Meta:
-        model = Section
-        fields = [
-            "id", "title", "order", "start_chapter_index",
-            "end_chapter_index", "estimated_reading_minutes", "created_at",
-        ]
-        read_only_fields = ["id", "created_at"]
-
-
-class SectionAdjustSerializer(serializers.Serializer):
-    """Payload for manual section adjustments (merge/split)."""
-    operation = serializers.ChoiceField(choices=["merge", "split"])
-    section_ids = serializers.ListField(
-        child=serializers.IntegerField(), min_length=1,
-        help_text="For merge: list of section IDs to merge. For split: [section_id] to split."
-    )
-    split_at = serializers.IntegerField(
-        required=False, default=2, min_value=2,
-        help_text="Number of new sections when splitting"
-    )
-
-
-class ReadingScheduleSerializer(serializers.ModelSerializer):
-    section_details = serializers.SerializerMethodField()
-
-    class Meta:
-        model = ReadingSchedule
-        fields = [
-            "id", "meeting_number", "week_date", "section_ids",
-            "section_details", "created_at",
-        ]
-        read_only_fields = ["id", "created_at"]
-
-    def get_section_details(self, obj: ReadingSchedule) -> list[dict]:
-        sections = Section.objects.filter(
-            id__in=obj.section_ids, group_book=obj.group_book
-        ).order_by("order")
-        return SectionSerializer(sections, many=True).data
-
-
-class MemberProgressSerializer(serializers.ModelSerializer):
     user_email = serializers.CharField(source="user.email", read_only=True)
-    user_username = serializers.CharField(source="user.username", read_only=True)
+    group_name = serializers.CharField(source="group.name", read_only=True)
-    current_section_title = serializers.SerializerMethodField()
 
     class Meta:
-        model = MemberProgress
+        model = GroupMembership
-        fields = [
+        fields = ["id", "user", "user_email", "group", "group_name", "role", "joined_at"]
-            "id", "user", "user_email", "user_username",
+        read_only_fields = ["id", "joined_at"]
-            "current_section", "current_section_title",
-            "completed_sections", "updated_at",
-        ]
-        read_only_fields = ["id", "updated_at"]
-
-    def get_current_section_title(self, obj: MemberProgress) -> str | None:
-        if obj.current_section:
-            return obj.current_section.title
-        return None
 
 
-class GroupBookListSerializer(serializers.ModelSerializer):
+class PaceNotificationSerializer(serializers.ModelSerializer):
-    ebook = EBookListSerializer(read_only=True)
+    status_display = serializers.CharField(source="get_status_display", read_only=True)
-    uploaded_by_email = serializers.CharField(source="uploaded_by.email", read_only=True)
-    section_count = serializers.SerializerMethodField()
 
     class Meta:
-        model = GroupBook
+        model = PaceNotification
         fields = [
-            "id", "title", "status", "ebook", "uploaded_by",
+            "id",
-            "uploaded_by_email", "section_count", "created_at", "updated_at",
+            "user",
+            "meeting",
+            "ebook",
+            "status",
+            "status_display",
+            "current_section",
+            "target_section",
+            "ahead_behind_delta",
+            "created_at",
         ]
-
+        read_only_fields = ["id", "created_at"]
-    def get_section_count(self, obj: GroupBook) -> int:
-        return obj.sections.count()
 
 
-class GroupBookDetailSerializer(serializers.ModelSerializer):
+class PaceStatusSerializer(serializers.Serializer):
-    ebook = EBookListSerializer(read_only=True)
+    meeting_id = serializers.IntegerField()
-    uploaded_by_email = serializers.CharField(source="uploaded_by.email", read_only=True)
+    meeting_title = serializers.CharField()
-    sections = SectionSerializer(many=True, read_only=True)
+    scheduled_at = serializers.CharField()
-    schedules = ReadingScheduleSerializer(source="schedules", many=True, read_only=True)
+    target_section = serializers.IntegerField()
-
+    target_section_label = serializers.CharField()
-    class Meta:
+    current_section = serializers.IntegerField()
-        model = GroupBook
+    ahead_behind_delta = serializers.IntegerField()
-        fields = [
+    status = serializers.CharField()
-            "id", "group", "title", "status", "ebook",
+    days_until_meeting = serializers.IntegerField()
-            "uploaded_by", "uploaded_by_email",
+    sections_to_catch_up = serializers.IntegerField()
-            "sections", "schedules", "created_at", "updated_at",
-        ]
-
-
-class GroupBookCreateSerializer(serializers.Serializer):
     ebook_id = serializers.IntegerField()
-    title = serializers.CharField(max_length=512, required=False)
+    ebook_title = serializers.CharField()
 
-    def validate_ebook_id(self, value: int) -> int:
-        from apps.books.models import EBook
-        if not EBook.objects.filter(id=value).exists():
-            raise serializers.ValidationError("EBook not found.")
-        # Check format is EPUB
-        ebook = EBook.objects.get(id=value)
-        if ebook.format != "epub":
-            raise serializers.ValidationError("Only EPUB format is supported for group books.")
-        return value
 
-    def validate(self, data: dict) -> dict:
+class ReminderSerializer(serializers.Serializer):
-        request = self.context.get("request")
+    meeting_id = serializers.IntegerField()
-        if request and not data.get("title"):
+    meeting_title = serializers.CharField()
-            from apps.books.models import EBook
+    scheduled_at = serializers.CharField()
-            ebook = EBook.objects.get(id=data["ebook_id"])
+    target_section = serializers.IntegerField()
-            data["title"] = ebook.title
+    target_section_label = serializers.CharField()
-        return data
+    group_name = serializers.CharField()
+    hours_until = serializers.IntegerField()
+    ebook_id = serializers.IntegerField()
+    ebook_title = serializers.CharField()

backend/apps/groups/services/pace.py

@@ -0,0 +1,219 @@
+"""Pace calculation service for reading progress vs meeting targets."""
+
+from __future__ import annotations
+
+import logging
+from datetime import datetime, timedelta
+from typing import TypedDict
+
+from django.db.models import QuerySet
+from django.utils import timezone
+
+from apps.books.models import EBook, ReadingProgress
+from apps.groups.models import (
+    GroupMeeting,
+    GroupMembership,
+    NotificationPreference,
+    PaceNotification,
+    NotificationStatus,
+)
+
+logger = logging.getLogger(__name__)
+
+
+class PaceStatus(TypedDict):
+    meeting_id: int
+    meeting_title: str
+    scheduled_at: str
+    target_section: int
+    target_section_label: str
+    current_section: int
+    ahead_behind_delta: int
+    status: str  # "ahead", "behind", "on_track", "completed"
+    days_until_meeting: int
+    sections_to_catch_up: int
+    ebook_id: int
+    ebook_title: str
+
+
+def get_relevant_ebooks_for_user(user) -> QuerySet[EBook]:
+    """Return ebooks that belong to groups the user is a member of."""
+    group_ids = (
+        GroupMembership.objects.filter(user=user)
+        .values_list("group_id", flat=True)
+    )
+    return (
+        EBook.objects.filter(reading_groups__in=group_ids)
+        .select_related("reading_progress")
+        .prefetch_related("chapters")
+        .distinct()
+    )
+
+
+def calculate_pace(
+    user,
+    ebook: EBook | None = None,
+    meeting: GroupMeeting | None = None,
+) -> list[PaceStatus]:
+    """Calculate reading pace for a user's upcoming meetings.
+
+    Compares the user's current reading progress (chapter index) against
+    the target section for each upcoming meeting within 3 days.
+    """
+    now = timezone.now()
+    three_days_from_now = now + timedelta(days=3)
+
+    # Find upcoming meetings for groups the user belongs to
+    user_group_ids = (
+        GroupMembership.objects.filter(user=user)
+        .values_list("group_id", flat=True)
+    )
+    meetings_qs = GroupMeeting.objects.filter(
+        group_id__in=user_group_ids,
+        scheduled_at__gte=now,
+        scheduled_at__lte=three_days_from_now,
+    ).select_related("group", "group__ebook")
+
+    if meeting:
+        meetings_qs = meetings_qs.filter(pk=meeting.pk)
+
+    meetings = list(meetings_qs)
+
+    results: list[PaceStatus] = []
+
+    for m in meetings:
+        group_ebook = m.group.ebook
+        ebooks_to_check: list[EBook] = []
+
+        if ebook:
+            ebooks_to_check = [ebook]
+        elif group_ebook:
+            ebooks_to_check = [group_ebook]
+        else:
+            # Check all ebooks in the group
+            ebooks_to_check = list(
+                EBook.objects.filter(reading_groups=m.group)
+                .select_related("reading_progress")
+                .prefetch_related("chapters")
+            )
+
+        for eb in ebooks_to_check:
+            pace = _compute_single_pace(user, m, eb, now)
+            if pace:
+                results.append(pace)
+
+    return results
+
+
+def _compute_single_pace(
+    user,
+    meeting: GroupMeeting,
+    ebook: EBook,
+    now: datetime,
+) -> PaceStatus | None:
+    """Compute pace for one user + meeting + ebook combination."""
+    try:
+        progress = ebook.reading_progress
+    except ReadingProgress.DoesNotExist:
+        # No progress yet — user hasn't started reading
+        return None
+
+    # Current section: based on last_page (chapter index) or computed from progress %
+    if progress.last_page > 0:
+        current_section = progress.last_page
+    elif progress.current_position > 0:
+        chapter_count = ebook.chapters.count() or ebook.page_count or 1
+        current_section = max(1, int((progress.current_position / 100) * chapter_count))
+    else:
+        current_section = 0
+
+    target_section = meeting.target_section or 0
+    if target_section == 0:
+        return None
+
+    delta = current_section - target_section
+    days_until = max(0, (meeting.scheduled_at - now).days)
+
+    if current_section >= target_section:
+        if current_section >= target_section and progress.current_position > 0:
+            status = "completed"
+        else:
+            status = "ahead"
+    elif delta >= -1:
+        status = "on_track"
+    else:
+        status = "behind"
+
+    return PaceStatus(
+        meeting_id=meeting.pk,
+        meeting_title=meeting.title or meeting.target_section_label,
+        scheduled_at=meeting.scheduled_at.isoformat(),
+        target_section=target_section,
+        target_section_label=meeting.target_section_label,
+        current_section=current_section,
+        ahead_behind_delta=delta,
+        status=status,
+        days_until_meeting=days_until,
+        sections_to_catch_up=max(0, target_section - current_section),
+        ebook_id=ebook.pk,
+        ebook_title=ebook.title,
+    )
+
+
+def should_send_notification(
+    user,
+    meeting: GroupMeeting,
+    ebook: EBook,
+) -> bool:
+    """Check if a pace notification should be sent based on user preferences."""
+    pref, _ = NotificationPreference.objects.get_or_create(user=user)
+
+    if not pref.pace_notifications_enabled:
+        return False
+
+    # Check if notification was already sent today
+    today = timezone.now().date()
+    existing = PaceNotification.objects.filter(
+        user=user,
+        meeting=meeting,
+        ebook=ebook,
+        created_at__date=today,
+    ).exclude(status=NotificationStatus.DISMISSED)
+
+    if existing.exists():
+        return False
+
+    # Frequency check
+    if pref.frequency == "weekly":
+        week_ago = today - timedelta(days=7)
+        recent = PaceNotification.objects.filter(
+            user=user,
+            meeting=meeting,
+            ebook=ebook,
+            created_at__date__gte=week_ago,
+        ).exclude(status=NotificationStatus.DISMISSED)
+        if recent.exists():
+            return False
+
+    return True
+
+
+def get_reminder_meetings(user) -> list[GroupMeeting]:
+    """Get meetings that are within 24 hours for reminder notifications."""
+    now = timezone.now()
+    tomorrow = now + timedelta(days=1)
+
+    user_group_ids = (
+        GroupMembership.objects.filter(user=user)
+        .values_list("group_id", flat=True)
+    )
+
+    return list(
+        GroupMeeting.objects.filter(
+            group_id__in=user_group_ids,
+            scheduled_at__gte=now,
+            scheduled_at__lte=tomorrow,
+        )
+        .select_related("group", "group__ebook")
+        .order_by("scheduled_at")
+    )

backend/apps/groups/services/section_splitting.py

@@ -1,241 +0,0 @@
-"""Automatic section detection and meeting recommendation for group books."""
-
-from __future__ import annotations
-
-import logging
-from datetime import date, timedelta
-from typing import Any
-
-from django.db.models import QuerySet
-
-from apps.books.models import BookChapter, EBook
-from apps.groups.models import GroupBook, ReadingSchedule, Section
-
-logger = logging.getLogger(__name__)
-
-WORDS_PER_MINUTE = 250  # Average reading speed
-
-
-def _fetch_chapter_text(ebook: EBook, chapter: BookChapter) -> str:
-    """Extract plain text from a chapter for word counting."""
-    try:
-        from ebooklib import epub
-        from bs4 import BeautifulSoup
-    except ImportError:
-        return ""
-
-    try:
-        book = epub.read_epub(ebook.file.path)
-        href = chapter.href or ""
-        for item in book.get_items():
-            item_name = item.get_name() or ""
-            if href and (item_name.endswith(href) or href.endswith(item_name)):
-                content = item.get_content()
-                soup = BeautifulSoup(content, "html.parser")
-                body = soup.find("body")
-                if body:
-                    return body.get_text(separator=" ", strip=True)
-                return soup.get_text(separator=" ", strip=True)
-        return ""
-    except Exception:
-        logger.exception("Failed to extract text for chapter %s", chapter.id)
-        return ""
-
-
-def _estimate_reading_minutes(text: str) -> int:
-    """Estimate reading time based on word count at WORDS_PER_MINUTE."""
-    word_count = len(text.split())
-    if word_count == 0:
-        return 1
-    return max(1, round(word_count / WORDS_PER_MINUTE))
-
-
-def detect_sections(group_book: GroupBook) -> list[dict[str, Any]]:
-    """Auto-detect sections from a GroupBook's chapters.
-
-    Groups consecutive chapters into logical sections based on TOC structure.
-    Top-level TOC entries become sections; if there are very few (< 3),
-    groups of ~5 chapters become sections instead.
-    """
-    ebook = group_book.ebook
-    chapters = list(
-        BookChapter.objects.filter(ebook=ebook).order_by("index").select_related("ebook")
-    )
-
-    if not chapters:
-        return []
-
-    top_level = [ch for ch in chapters if not ch.children or len(ch.children) == 0]
-    has_children = [ch for ch in chapters if ch.children and len(ch.children) > 0]
-
-    sections: list[dict[str, Any]] = []
-
-    if len(has_children) >= 3:
-        # Use TOC structure: each top-level chapter (with children) is a section
-        for idx, ch in enumerate(has_children):
-            # Find all child chapters belonging to this parent
-            child_indices = _collect_child_indices(chapters, ch, idx)
-            start_idx = ch.index
-            end_idx = child_indices[-1] if child_indices else start_idx
-
-            section_chapters = [c for c in chapters if start_idx <= c.index <= end_idx]
-            total_text = ""
-            for sc in section_chapters:
-                total_text += " " + _fetch_chapter_text(ebook, sc)
-
-            sections.append({
-                "title": ch.title,
-                "order": idx + 1,
-                "start_chapter_index": start_idx,
-                "end_chapter_index": end_idx + 1,
-                "estimated_reading_minutes": _estimate_reading_minutes(total_text),
-            })
-    else:
-        # Group chapters into chunks of ~5
-        chunk_size = max(1, len(top_level) // 6 if len(top_level) > 6 else 5)
-        chunk_size = max(3, min(chunk_size, 10))
-
-        group_start = 0
-        section_order = 1
-        total = len(top_level) or len(chapters)
-        source = top_level or chapters
-
-        while group_start < total:
-            group_end = min(group_start + chunk_size, total)
-            chunk = source[group_start:group_end]
-
-            total_text = ""
-            for ch in chunk:
-                total_text += " " + _fetch_chapter_text(ebook, ch)
-
-            first_title = chunk[0].title if chunk else "Section"
-            last_title = chunk[-1].title if len(chunk) > 1 else ""
-            title = f"{first_title}" if not last_title or first_title == last_title else f"{first_title} — {last_title}"
-
-            sections.append({
-                "title": title,
-                "order": section_order,
-                "start_chapter_index": chunk[0].index,
-                "end_chapter_index": chunk[-1].index + 1,
-                "estimated_reading_minutes": _estimate_reading_minutes(total_text),
-            })
-            group_start = group_end
-            section_order += 1
-
-    return sections
-
-
-def _collect_child_indices(chapters: list[BookChapter], parent: BookChapter, parent_idx: int) -> list[int]:
-    """Collect indices of all chapters that are children of the given parent TOC entry."""
-    indices: list[int] = [parent.index]
-    child_hrefs: set[str] = set()
-    for child in parent.children:
-        if isinstance(child, dict):
-            child_hrefs.add(child.get("href", ""))
-        elif hasattr(child, "href"):
-            child_hrefs.add(getattr(child, "href", ""))
-
-    for ch in chapters:
-        if ch.index == parent.index:
-            continue
-        if ch.href in child_hrefs or any(
-            ch.href.endswith(h) or h.endswith(ch.href) for h in child_hrefs
-        ):
-            indices.append(ch.index)
-
-    # Also include chapters between this parent and the next parent
-    if parent_idx + 1 < len(chapters):
-        next_parent = chapters[parent_idx + 1]
-        for ch in chapters:
-            if parent.index < ch.index < next_parent.index:
-                indices.append(ch.index)
-
-    return sorted(set(indices))
-
-
-def apply_sections(group_book: GroupBook) -> list[Section]:
-    """Detect sections and persist them to the database, replacing existing ones."""
-    Section.objects.filter(group_book=group_book).delete()
-    sections_data = detect_sections(group_book)
-    created: list[Section] = []
-    for data in sections_data:
-        section = Section.objects.create(
-            group_book=group_book,
-            title=data["title"],
-            order=data["order"],
-            start_chapter_index=data["start_chapter_index"],
-            end_chapter_index=data["end_chapter_index"],
-            estimated_reading_minutes=data["estimated_reading_minutes"],
-        )
-        created.append(section)
-    return created
-
-
-def recommend_meetings(group_book: GroupBook, num_meetings: int = 4) -> list[dict[str, Any]]:
-    """Recommend which sections to assign to each weekly meeting.
-
-    Distributes sections across meetings, trying to balance total reading time.
-    Returns a list of meeting assignments ready for schedule creation.
-    """
-    sections = list(
-        Section.objects.filter(group_book=group_book).order_by("order")
-    )
-
-    if not sections:
-        return []
-
-    # Calculate total minutes to distribute
-    total_minutes = sum(s.estimated_reading_minutes for s in sections)
-    target_per_meeting = total_minutes / num_meetings
-
-    meetings: list[dict[str, Any]] = []
-    current_meeting: list[int] = []
-    current_minutes = 0
-
-    for section in sections:
-        if current_meeting and current_minutes + section.estimated_reading_minutes > target_per_meeting * 1.4:
-            # Start new meeting if adding this section would overshoot too much
-            if len(meetings) < num_meetings - 1:
-                meetings.append({
-                    "meeting_number": len(meetings) + 1,
-                    "section_ids": current_meeting,
-                    "total_minutes": current_minutes,
-                })
-                current_meeting = []
-                current_minutes = 0
-
-        current_meeting.append(section.id)
-        current_minutes += section.estimated_reading_minutes
-
-    # Add the last meeting
-    if current_meeting:
-        meetings.append({
-            "meeting_number": len(meetings) + 1,
-            "section_ids": current_meeting,
-            "total_minutes": current_minutes,
-        })
-
-    # If we have fewer than num_meetings, we could split the largest one
-    # For now, just return what we have
-    return meetings
-
-
-def apply_schedule(group_book: GroupBook, num_meetings: int = 4) -> list[ReadingSchedule]:
-    """Generate and persist a reading schedule."""
-    ReadingSchedule.objects.filter(group_book=group_book).delete()
-
-    recommendations = recommend_meetings(group_book, num_meetings)
-    today = date.today()
-
-    created: list[ReadingSchedule] = []
-    for rec in recommendations:
-        week_date = today + timedelta(weeks=rec["meeting_number"] - 1)
-        schedule = ReadingSchedule.objects.create(
-            group_book=group_book,
-            meeting_number=rec["meeting_number"],
-            week_date=week_date,
-            section_ids=rec["section_ids"],
-        )
-        created.append(schedule)
-
-    return created

backend/apps/groups/urls.py

@@ -1,43 +1,23 @@
 from django.urls import include, path
 from rest_framework.routers import DefaultRouter
 
-from apps.groups.views import GroupBookViewSet, ReadingGroupViewSet
+from apps.groups.views import (
+    GroupMeetingViewSet,
+    ReadingGroupViewSet,
+    dismiss_pace_notification_view,
+    notification_preferences_view,
+    pace_status_view,
+    reminder_view,
+)
 
-# ReadingGroup routes (standard ViewSet)
 router = DefaultRouter()
-router.register(r"", ReadingGroupViewSet, basename="group")
+router.register(r"groups", ReadingGroupViewSet, basename="reading-group")
+router.register(r"meetings", GroupMeetingViewSet, basename="group-meeting")
 
 urlpatterns = [
     path("", include(router.urls)),
-    # Nested GroupBook routes under a group
+    path("notifications/preferences/", notification_preferences_view, name="notification-preferences"),
-    path(
+    path("notifications/pace/", pace_status_view, name="pace-status"),
-        "<int:group_pk>/books/",
+    path("notifications/dismiss/", dismiss_pace_notification_view, name="dismiss-pace"),
-        GroupBookViewSet.as_view({"get": "list", "post": "create"}),
+    path("notifications/reminders/", reminder_view, name="meeting-reminders"),
-        name="group-book-list",
-    ),
-    path(
-        "<int:group_pk>/books/<int:pk>/",
-        GroupBookViewSet.as_view({"get": "retrieve", "delete": "destroy"}),
-        name="group-book-detail",
-    ),
-    path(
-        "<int:group_pk>/books/<int:pk>/detect-sections/",
-        GroupBookViewSet.as_view({"post": "detect_sections_action"}),
-        name="group-book-detect-sections",
-    ),
-    path(
-        "<int:group_pk>/books/<int:pk>/adjust-sections/",
-        GroupBookViewSet.as_view({"post": "adjust_sections"}),
-        name="group-book-adjust-sections",
-    ),
-    path(
-        "<int:group_pk>/books/<int:pk>/schedule/",
-        GroupBookViewSet.as_view({"get": "schedule", "post": "schedule", "delete": "schedule"}),
-        name="group-book-schedule",
-    ),
-    path(
-        "<int:group_pk>/books/<int:pk>/progress/",
-        GroupBookViewSet.as_view({"get": "progress", "patch": "progress"}),
-        name="group-book-progress",
-    ),
 ]

backend/apps/groups/views.py

@@ -1,349 +1,207 @@
 from __future__ import annotations
 
-import logging
-from typing import Any
-
 from django.db.models import QuerySet
-from django.shortcuts import get_object_or_404
 from rest_framework import permissions, status, viewsets
-from rest_framework.decorators import action
+from rest_framework.decorators import action, api_view, permission_classes
+from rest_framework.permissions import IsAuthenticated
 from rest_framework.request import Request
 from rest_framework.response import Response
 
 from apps.books.models import EBook
 from apps.groups.models import (
-    GroupBook,
+    GroupMeeting,
-    MemberProgress,
+    GroupMembership,
+    NotificationPreference,
+    PaceNotification,
+    NotificationStatus,
     ReadingGroup,
-    ReadingGroupMembership,
-    ReadingSchedule,
-    Section,
 )
 from apps.groups.serializers import (
-    AddMemberSerializer,
+    GroupMeetingSerializer,
-    GroupBookCreateSerializer,
+    GroupMembershipSerializer,
-    GroupBookDetailSerializer,
+    NotificationPreferenceSerializer,
-    GroupBookListSerializer,
+    PaceNotificationSerializer,
-    MemberProgressSerializer,
+    PaceStatusSerializer,
-    ReadingGroupCreateSerializer,
+    ReadingGroupSerializer,
-    ReadingGroupDetailSerializer,
+    ReminderSerializer,
-    ReadingGroupListSerializer,
-    ReadingScheduleSerializer,
-    SectionAdjustSerializer,
-    SectionSerializer,
 )
-from apps.groups.services.section_splitting import (
+from apps.groups.services.pace import (
-    apply_schedule,
+    calculate_pace,
-    apply_sections,
+    get_reminder_meetings,
-    detect_sections,
+    should_send_notification,
 )
 
-logger = logging.getLogger(__name__)
-
-
-class IsGroupAdmin(permissions.BasePermission):
-    """Only the group admin can modify group resources."""
-
-    def has_permission(self, request: Request, view: object) -> bool:
-        if not request.user.is_authenticated:
-            return False
-        if view.action in ("list", "retrieve"):
-            return True
-        group_id = view.kwargs.get("pk") or view.kwargs.get("group_pk")
-        if group_id:
-            return ReadingGroup.objects.filter(id=group_id, admin=request.user).exists()
-        return True
-
-    def has_object_permission(self, request: Request, view: object, obj: ReadingGroup) -> bool:
-        if request.method in permissions.SAFE_METHODS:
-            return True
-        return obj.admin == request.user
-
 
 class IsGroupMember(permissions.BasePermission):
-    """Only group members (including admin) can view group content."""
+    """Only allow group members to access group resources."""
 
-    def has_permission(self, request: Request, view: object) -> bool:
+    def has_object_permission(self, request: Request, view: object, obj: ReadingGroup) -> bool:
-        if not request.user.is_authenticated:
+        return obj.memberships.filter(user=request.user).exists()
-            return False
-        group_id = view.kwargs.get("pk") or view.kwargs.get("group_pk")
-        if group_id:
-            return ReadingGroupMembership.objects.filter(
-                group_id=group_id, user=request.user
-            ).exists()
-        return True
 
 
 class ReadingGroupViewSet(viewsets.ModelViewSet):
-    permission_classes = [permissions.IsAuthenticated, IsGroupAdmin]
+    permission_classes = [IsAuthenticated, IsGroupMember]
-    queryset = ReadingGroup.objects.prefetch_related("memberships__user")
+    serializer_class = ReadingGroupSerializer
-
-    def get_serializer_class(self):
-        if self.action == "create":
-            return ReadingGroupCreateSerializer
-        if self.action == "retrieve":
-            return ReadingGroupDetailSerializer
-        return ReadingGroupListSerializer
 
     def get_queryset(self) -> QuerySet[ReadingGroup]:
-        user = self.request.user
+        return (
-        return ReadingGroup.objects.filter(
+            ReadingGroup.objects.filter(memberships__user=self.request.user)
-            memberships__user=user
+            .prefetch_related("memberships", "meetings")
-        ).prefetch_related("memberships__user").distinct()
+            .distinct()
-
-    def perform_create(self, serializer: ReadingGroupCreateSerializer) -> ReadingGroup:
-        group = serializer.save(admin=self.request.user)
-        ReadingGroupMembership.objects.create(
-            user=self.request.user, group=group, role=ReadingGroupMembership.Role.ADMIN
-        )
-        return group
-
-    @action(detail=True, methods=["post"], permission_classes=[IsGroupAdmin])
-    def add_member(self, request: Request, pk: int | None = None) -> Response:
-        group = self.get_object()
-        member_serializer = AddMemberSerializer(data=request.data)
-        member_serializer.is_valid(raise_exception=True)
-
-        user_id = member_serializer.validated_data["user_id"]
-        from django.conf import settings
-        User = settings.AUTH_USER_MODEL
-        new_member = get_object_or_404(User, id=user_id)
-
-        if ReadingGroupMembership.objects.filter(group=group, user=new_member).exists():
-            return Response(
-                {"detail": "User is already a member of this group."},
-                status=status.HTTP_409_CONFLICT,
-            )
-
-        membership = ReadingGroupMembership.objects.create(
-            user=new_member, group=group, role=ReadingGroupMembership.Role.MEMBER
-        )
-        from apps.groups.serializers import ReadingGroupMembershipSerializer
-        return Response(
-            ReadingGroupMembershipSerializer(membership).data,
-            status=status.HTTP_201_CREATED,
         )
 
-    @action(detail=True, methods=["post"], permission_classes=[IsGroupAdmin])
+    def perform_create(self, serializer) -> None:
-    def remove_member(self, request: Request, pk: int | None = None) -> Response:
+        group = serializer.save(created_by=self.request.user)
-        group = self.get_object()
+        GroupMembership.objects.create(
-        member_serializer = AddMemberSerializer(data=request.data)
+            user=self.request.user,
-        member_serializer.is_valid(raise_exception=True)
-
-        user_id = member_serializer.validated_data["user_id"]
-        if user_id == group.admin_id:
-            return Response(
-                {"detail": "Cannot remove the group admin."},
-                status=status.HTTP_400_BAD_REQUEST,
-            )
-
-        deleted, _ = ReadingGroupMembership.objects.filter(
-            group=group, user_id=user_id
-        ).delete()
-        if not deleted:
-            return Response(
-                {"detail": "User is not a member of this group."},
-                status=status.HTTP_404_NOT_FOUND,
-            )
-        return Response(status=status.HTTP_204_NO_CONTENT)
-
-
-class GroupBookViewSet(viewsets.ModelViewSet):
-    permission_classes = [permissions.IsAuthenticated, IsGroupAdmin]
-
-    def get_serializer_class(self):
-        if self.action == "create":
-            return GroupBookCreateSerializer
-        if self.action == "retrieve":
-            return GroupBookDetailSerializer
-        return GroupBookListSerializer
-
-    def get_queryset(self) -> QuerySet[GroupBook]:
-        group_id = self.kwargs.get("group_pk")
-        return GroupBook.objects.filter(
-            group_id=group_id
-        ).select_related("ebook", "ebook__user", "uploaded_by").prefetch_related(
-            "sections", "schedules"
-        )
-
-    def perform_create(self, serializer: GroupBookCreateSerializer) -> GroupBook:
-        group = get_object_or_404(ReadingGroup, id=self.kwargs["group_pk"])
-        ebook = get_object_or_404(EBook, id=serializer.validated_data["ebook_id"])
-        title = serializer.validated_data.get("title") or ebook.title
-
-        # Mark existing active books as replaced
-        GroupBook.objects.filter(group=group, status=GroupBook.Status.ACTIVE).update(
-            status=GroupBook.Status.REPLACED
-        )
-
-        group_book = GroupBook.objects.create(
             group=group,
-            ebook=ebook,
+            role="admin",
-            uploaded_by=self.request.user,
-            title=title,
-            status=GroupBook.Status.ACTIVE,
         )
 
-        # Auto-detect sections
+    @action(detail=False, methods=["get"], url_path="all")
-        try:
+    def all_groups(self, request: Request) -> Response:
-            apply_sections(group_book)
+        """Return all groups (for discovery)."""
-        except Exception:
+        qs = ReadingGroup.objects.all().prefetch_related("memberships", "meetings")
-            logger.exception("Auto-section detection failed for group_book %s", group_book.id)
+        page = self.paginate_queryset(qs)
-
+        if page is not None:
-        # Auto-generate schedule
+            serializer = self.get_serializer(page, many=True)
-        try:
+            return self.get_paginated_response(serializer.data)
-            apply_schedule(group_book)
+        serializer = self.get_serializer(qs, many=True)
-        except Exception:
-            logger.exception("Schedule generation failed for group_book %s", group_book.id)
-
-        return group_book
-
-    @action(detail=True, methods=["post"], url_path="detect-sections")
-    def detect_sections_action(self, request: Request, group_pk: int | None = None, pk: int | None = None) -> Response:
-        group_book = self.get_object()
-        try:
-            sections = apply_sections(group_book)
-        except Exception as exc:
-            logger.exception("Section detection failed for group_book %s", group_book.id)
-            return Response({"error": str(exc)}, status=status.HTTP_500_INTERNAL_SERVER_ERROR)
-        return Response(SectionSerializer(sections, many=True).data)
-
-    @action(detail=True, methods=["post"], url_path="adjust-sections")
-    def adjust_sections(self, request: Request, group_pk: int | None = None, pk: int | None = None) -> Response:
-        group_book = self.get_object()
-        adjust_serializer = SectionAdjustSerializer(data=request.data)
-        adjust_serializer.is_valid(raise_exception=True)
-
-        operation = adjust_serializer.validated_data["operation"]
-        section_ids: list[int] = adjust_serializer.validated_data["section_ids"]
-
-        if operation == "merge":
-            if len(section_ids) < 2:
-                return Response(
-                    {"error": "At least 2 section IDs required for merge."},
-                    status=status.HTTP_400_BAD_REQUEST,
-                )
-            sections = list(
-                Section.objects.filter(id__in=section_ids, group_book=group_book).order_by("order")
-            )
-            if len(sections) < 2:
-                return Response(
-                    {"error": "Not enough valid sections found."},
-                    status=status.HTTP_400_BAD_REQUEST,
-                )
-            merged_title = " — ".join(s.title for s in sections)
-            merged_minutes = sum(s.estimated_reading_minutes for s in sections)
-            merged_start = sections[0].start_chapter_index
-            merged_end = sections[-1].end_chapter_index
-            merged_order = sections[0].order
-
-            # Delete old sections
-            Section.objects.filter(id__in=section_ids, group_book=group_book).delete()
-
-            # Create merged section
-            merged = Section.objects.create(
-                group_book=group_book,
-                title=merged_title,
-                order=merged_order,
-                start_chapter_index=merged_start,
-                end_chapter_index=merged_end,
-                estimated_reading_minutes=merged_minutes,
-            )
-            # Reorder remaining sections
-            _renumber_sections(group_book)
-            return Response(SectionSerializer(merged).data)
-
-        if operation == "split":
-            if len(section_ids) != 1:
-                return Response(
-                    {"error": "Exactly 1 section ID required for split."},
-                    status=status.HTTP_400_BAD_REQUEST,
-                )
-            split_at = adjust_serializer.validated_data.get("split_at", 2)
-            section = get_object_or_404(Section, id=section_ids[0], group_book=group_book)
-            chapters = section.end_chapter_index - section.start_chapter_index
-            if chapters < split_at:
-                return Response(
-                    {"error": f"Section only has {chapters} chapters, cannot split into {split_at}."},
-                    status=status.HTTP_400_BAD_REQUEST,
-                )
-
-            # Delete original
-            orig_order = section.order
-            orig_title = section.title
-            section.delete()
-
-            # Create split sections
-            chunk_size = max(1, chapters // split_at)
-            new_sections: list[Section] = []
-            for i in range(split_at):
-                start_idx = section.start_chapter_index + i * chunk_size
-                end_idx = start_idx + chunk_size if i < split_at - 1 else section.end_chapter_index
-                minutes_each = max(1, section.estimated_reading_minutes // split_at)
-                new_sec = Section.objects.create(
-                    group_book=group_book,
-                    title=f"{orig_title} (Part {i + 1})",
-                    order=orig_order + i,
-                    start_chapter_index=start_idx,
-                    end_chapter_index=end_idx,
-                    estimated_reading_minutes=minutes_each,
-                )
-                new_sections.append(new_sec)
-
-            _renumber_sections(group_book)
-            return Response(SectionSerializer(new_sections, many=True).data)
-
-        return Response({"error": "Invalid operation."}, status=status.HTTP_400_BAD_REQUEST)
-
-    @action(detail=True, methods=["get", "post", "delete"], url_path="schedule")
-    def schedule(self, request: Request, group_pk: int | None = None, pk: int | None = None) -> Response:
-        group_book = self.get_object()
-
-        if request.method == "GET":
-            schedules = ReadingSchedule.objects.filter(group_book=group_book).order_by("meeting_number")
-            return Response(ReadingScheduleSerializer(schedules, many=True).data)
-
-        if request.method == "POST":
-            ReadingSchedule.objects.filter(group_book=group_book).delete()
-            num_meetings = int(request.data.get("num_meetings", 4))
-            try:
-                schedules = apply_schedule(group_book, num_meetings=num_meetings)
-            except Exception as exc:
-                logger.exception("Schedule generation failed for group_book %s", group_book.id)
-                return Response({"error": str(exc)}, status=status.HTTP_500_INTERNAL_SERVER_ERROR)
-            return Response(
-                ReadingScheduleSerializer(schedules, many=True).data,
-                status=status.HTTP_201_CREATED,
-            )
-
-        if request.method == "DELETE":
-            ReadingSchedule.objects.filter(group_book=group_book).delete()
-            return Response(status=status.HTTP_204_NO_CONTENT)
-
-    @action(detail=True, methods=["get", "patch"], url_path="progress")
-    def progress(self, request: Request, group_pk: int | None = None, pk: int | None = None) -> Response:
-        group_book = self.get_object()
-
-        if request.method == "GET":
-            progress_records = MemberProgress.objects.filter(
-                group_book=group_book
-            ).select_related("user", "current_section")
-            return Response(MemberProgressSerializer(progress_records, many=True).data)
-
-        # PATCH: update own progress
-        progress_obj, _created = MemberProgress.objects.get_or_create(
-            user=request.user, group_book=group_book,
-        )
-        serializer = MemberProgressSerializer(progress_obj, data=request.data, partial=True)
-        serializer.is_valid(raise_exception=True)
-        serializer.save()
         return Response(serializer.data)
 
 
-def _renumber_sections(group_book: GroupBook) -> None:
+class GroupMeetingViewSet(viewsets.ModelViewSet):
-    """Re-number sections sequentially by their current order."""
+    permission_classes = [IsAuthenticated]
-    sections = list(Section.objects.filter(group_book=group_book).order_by("order"))
+    serializer_class = GroupMeetingSerializer
-    for idx, section in enumerate(sections):
+
-        if section.order != idx + 1:
+    def get_queryset(self) -> QuerySet[GroupMeeting]:
-            section.order = idx + 1
+        user_group_ids = (
-            section.save(update_fields=["order"])
+            GroupMembership.objects.filter(user=self.request.user)
+            .values_list("group_id", flat=True)
+        )
+        return GroupMeeting.objects.filter(group_id__in=user_group_ids).select_related(
+            "group"
+        )
+
+    def perform_create(self, serializer) -> None:
+        group = serializer.validated_data["group"]
+        if not group.memberships.filter(user=self.request.user).exists():
+            raise permissions.PermissionDenied("You must be a group member to create meetings.")
+        serializer.save()
+
+    @action(detail=False, methods=["get"], url_path="upcoming")
+    def upcoming(self, request: Request) -> Response:
+        """Return upcoming meetings for the user's groups (within 3 days)."""
+        from django.utils import timezone
+        from datetime import timedelta
+
+        now = timezone.now()
+        three_days = now + timedelta(days=3)
+        qs = self.get_queryset().filter(
+            scheduled_at__gte=now,
+            scheduled_at__lte=three_days,
+        )
+        serializer = self.get_serializer(qs, many=True)
+        return Response(serializer.data)
+
+
+@api_view(["GET", "PATCH"])
+@permission_classes([IsAuthenticated])
+def notification_preferences_view(request: Request) -> Response:
+    """Get or update notification preferences for the current user."""
+    pref, _created = NotificationPreference.objects.get_or_create(user=request.user)
+
+    if request.method == "GET":
+        serializer = NotificationPreferenceSerializer(pref)
+        return Response(serializer.data)
+
+    serializer = NotificationPreferenceSerializer(pref, data=request.data, partial=True)
+    serializer.is_valid(raise_exception=True)
+    serializer.save()
+    return Response(serializer.data)
+
+
+@api_view(["GET"])
+@permission_classes([IsAuthenticated])
+def pace_status_view(request: Request) -> Response:
+    """Get reading pace status for the current user's upcoming meetings."""
+    ebook_id = request.query_params.get("ebook_id")
+    ebook: EBook | None = None
+
+    if ebook_id:
+        try:
+            ebook = EBook.objects.select_related("reading_progress").prefetch_related("chapters").get(
+                pk=ebook_id, user=request.user
+            )
+        except EBook.DoesNotExist:
+            return Response(
+                {"error": "EBook not found."}, status=status.HTTP_404_NOT_FOUND
+            )
+
+    pace_data = calculate_pace(request.user, ebook=ebook)
+    serializer = PaceStatusSerializer(pace_data, many=True)
+    return Response(serializer.data)
+
+
+@api_view(["POST"])
+@permission_classes([IsAuthenticated])
+def dismiss_pace_notification_view(request: Request) -> Response:
+    """Dismiss a pace notification so it won't show again."""
+    meeting_id = request.data.get("meeting_id")
+    ebook_id = request.data.get("ebook_id")
+
+    if not meeting_id or not ebook_id:
+        return Response(
+            {"error": "meeting_id and ebook_id are required."},
+            status=status.HTTP_400_BAD_REQUEST,
+        )
+
+    PaceNotification.objects.filter(
+        user=request.user,
+        meeting_id=meeting_id,
+        ebook_id=ebook_id,
+        status=NotificationStatus.PENDING,
+    ).update(status=NotificationStatus.DISMISSED)
+
+    return Response({"status": "dismissed"})
+
+
+@api_view(["GET"])
+@permission_classes([IsAuthenticated])
+def reminder_view(request: Request) -> Response:
+    """Get pre-meeting reminders for meetings within 24 hours."""
+    pref, _ = NotificationPreference.objects.get_or_create(user=request.user)
+    if not pref.reminder_enabled:
+        return Response([])
+
+    meetings = get_reminder_meetings(request.user)
+    now_dt = __import__("django").utils.timezone.now()
+
+    reminders = []
+    for mtg in meetings:
+        group_ebook = mtg.group.ebook
+        ebook: EBook | None = group_ebook
+        if not ebook:
+            ebooks = list(
+                EBook.objects.filter(reading_groups=mtg.group).select_related("reading_progress")[:1]
+            )
+            ebook = ebooks[0] if ebooks else None
+
+        if not ebook:
+            continue
+
+        hours_until = max(0, int((mtg.scheduled_at - now_dt).total_seconds() / 3600))
+        reminders.append({
+            "meeting_id": mtg.pk,
+            "meeting_title": mtg.title or mtg.target_section_label,
+            "scheduled_at": mtg.scheduled_at.isoformat(),
+            "target_section": mtg.target_section,
+            "target_section_label": mtg.target_section_label,
+            "group_name": mtg.group.name,
+            "hours_until": hours_until,
+            "ebook_id": ebook.pk,
+            "ebook_title": ebook.title,
+        })
+
+    serializer = ReminderSerializer(reminders, many=True)
+    return Response(serializer.data)

backend/config/django.py

@@ -39,9 +39,9 @@ INSTALLED_APPS = [
     # Local apps
     "apps.users",
     "apps.books",
-    "apps.groups",
     "apps.annotations",
     "apps.reader",
+    "apps.groups",
 ]
 
 MIDDLEWARE = [

backend/config/urls.py

@@ -6,9 +6,9 @@ urlpatterns = [
     path("admin/", admin.site.urls),
     path("api/auth/", include("apps.users.urls")),
     path("api/books/", include("apps.books.urls")),
-    path("api/groups/", include("apps.groups.urls")),
     path("api/annotations/", include("apps.annotations.urls")),
     path("api/reader/", include("apps.reader.urls")),
+    path("api/groups/", include("apps.groups.urls")),
 ]
 
 if settings.DEBUG:

frontend/src/App.tsx

@@ -12,9 +12,6 @@ const AddBookPage = lazy(() => import("./pages/AddBook").then((m) => ({ default:
 const SettingsPage = lazy(() => import("./pages/Settings").then((m) => ({ default: m.SettingsPage })));
 const BookmarksNotesPage = lazy(() => import("./components/annotations/BookmarksNotesPage").then((m) => ({ default: m.BookmarksNotesPage })));
 const ReadingPage = lazy(() => import("./pages/ReadingPage").then((m) => ({ default: m.default })));
-const GroupsPage = lazy(() => import("./pages/GroupsPage").then((m) => ({ default: m.GroupsPage })));
-const GroupDetailPage = lazy(() => import("./pages/GroupDetailPage").then((m) => ({ default: m.GroupDetailPage })));
-const GroupBookPage = lazy(() => import("./pages/GroupBookPage").then((m) => ({ default: m.GroupBookPage })));
 
 const AuthPage = lazy(() => import("./pages/AuthPage"));
 
@@ -47,9 +44,6 @@ function AppRoutes() {
         <Route path="/reader/:id" element={<ProtectedRoute><ReaderRedirect /></ProtectedRoute>} />
         <Route path="/add" element={<ProtectedRoute><AddBookPage /></ProtectedRoute>} />
         <Route path="/settings" element={<ProtectedRoute><SettingsPage /></ProtectedRoute>} />
-        <Route path="/groups" element={<ProtectedRoute><GroupsPage /></ProtectedRoute>} />
-        <Route path="/groups/:groupId" element={<ProtectedRoute><GroupDetailPage /></ProtectedRoute>} />
-        <Route path="/groups/:groupId/books/:bookId" element={<ProtectedRoute><GroupBookPage /></ProtectedRoute>} />
         <Route path="/bookmarks-notes/:bookId?" element={<ProtectedRoute><BookmarksNotesPage /></ProtectedRoute>} />
         <Route path="*" element={<Navigate to="/" replace />} />
       </Routes>

frontend/src/api/groups.ts

@@ -1,151 +1,57 @@
 import api from "./client";
 import type {
-  AddMemberPayload,
+  GroupMeeting,
-  AdjustSectionsPayload,
+  MeetingReminder,
-  CreateGroupBookPayload,
+  NotificationPreferences,
-  CreateGroupPayload,
+  PaceStatus,
-  GroupBook,
-  GroupBookDetail,
-  MemberProgress,
   ReadingGroup,
-  ReadingGroupDetail,
+} from "../types/notifications";
-  ReadingSchedule,
-  Section,
-} from "../types/group";
 
 export const groupsApi = {
-  // ---- Reading Groups ----
+  async getPaceStatus(ebookId?: number): Promise<PaceStatus[]> {
+    const params: Record<string, string> = {};
+    if (ebookId) params.ebook_id = String(ebookId);
+    const { data } = await api.get<PaceStatus[]>("/groups/notifications/pace/", { params });
+    return data;
+  },
 
-  async listGroups(): Promise<ReadingGroup[]> {
+  async getPreferences(): Promise<NotificationPreferences> {
+    const { data } = await api.get<NotificationPreferences>("/groups/notifications/preferences/");
+    return data;
+  },
+
+  async updatePreferences(
+    prefs: Partial<NotificationPreferences>,
+  ): Promise<NotificationPreferences> {
+    const { data } = await api.patch<NotificationPreferences>(
+      "/groups/notifications/preferences/",
+      prefs,
+    );
+    return data;
+  },
+
+  async dismissPaceNotification(meetingId: number, ebookId: number): Promise<void> {
+    await api.post("/groups/notifications/dismiss/", {
+      meeting_id: meetingId,
+      ebook_id: ebookId,
+    });
+  },
+
+  async getReminders(): Promise<MeetingReminder[]> {
+    const { data } = await api.get<MeetingReminder[]>("/groups/notifications/reminders/");
+    return data;
+  },
+
+  async getGroups(): Promise<ReadingGroup[]> {
     const { data } = await api.get<{ count: number; results: ReadingGroup[] } | ReadingGroup[]>(
-      "/groups/"
+      "/groups/groups/",
     );
     if (Array.isArray(data)) return data;
     return data.results ?? [];
   },
 
-  async getGroup(id: number): Promise<ReadingGroupDetail> {
+  async getUpcomingMeetings(): Promise<GroupMeeting[]> {
-    const { data } = await api.get<ReadingGroupDetail>(`/groups/${id}/`);
+    const { data } = await api.get<GroupMeeting[]>("/groups/meetings/upcoming/");
-    return data;
-  },
-
-  async createGroup(payload: CreateGroupPayload): Promise<ReadingGroup> {
-    const { data } = await api.post<ReadingGroup>("/groups/", payload);
-    return data;
-  },
-
-  async deleteGroup(id: number): Promise<void> {
-    await api.delete(`/groups/${id}/`);
-  },
-
-  async addMember(groupId: number, payload: AddMemberPayload): Promise<void> {
-    await api.post(`/groups/${groupId}/add_member/`, payload);
-  },
-
-  async removeMember(groupId: number, payload: AddMemberPayload): Promise<void> {
-    await api.post(`/groups/${groupId}/remove_member/`, payload);
-  },
-
-  // ---- Group Books ----
-
-  async listGroupBooks(groupId: number): Promise<GroupBook[]> {
-    const { data } = await api.get<GroupBook[]>(`/groups/${groupId}/books/`);
-    return Array.isArray(data) ? data : (data as { results: GroupBook[] }).results ?? [];
-  },
-
-  async getGroupBook(groupId: number, bookId: number): Promise<GroupBookDetail> {
-    const { data } = await api.get<GroupBookDetail>(`/groups/${groupId}/books/${bookId}/`);
-    return data;
-  },
-
-  async createGroupBook(
-    groupId: number,
-    payload: CreateGroupBookPayload
-  ): Promise<GroupBookDetail> {
-    const { data } = await api.post<GroupBookDetail>(
-      `/groups/${groupId}/books/`,
-      payload
-    );
-    return data;
-  },
-
-  async deleteGroupBook(groupId: number, bookId: number): Promise<void> {
-    await api.delete(`/groups/${groupId}/books/${bookId}/`);
-  },
-
-  // ---- Sections ----
-
-  async detectSections(
-    groupId: number,
-    bookId: number
-  ): Promise<Section[]> {
-    const { data } = await api.post<Section[]>(
-      `/groups/${groupId}/books/${bookId}/detect-sections/`
-    );
-    return data;
-  },
-
-  async adjustSections(
-    groupId: number,
-    bookId: number,
-    payload: AdjustSectionsPayload
-  ): Promise<Section | Section[]> {
-    const { data } = await api.post<Section | Section[]>(
-      `/groups/${groupId}/books/${bookId}/adjust-sections/`,
-      payload
-    );
-    return data;
-  },
-
-  // ---- Schedule ----
-
-  async getSchedule(
-    groupId: number,
-    bookId: number
-  ): Promise<ReadingSchedule[]> {
-    const { data } = await api.get<ReadingSchedule[]>(
-      `/groups/${groupId}/books/${bookId}/schedule/`
-    );
-    return data;
-  },
-
-  async generateSchedule(
-    groupId: number,
-    bookId: number,
-    numMeetings: number = 4
-  ): Promise<ReadingSchedule[]> {
-    const { data } = await api.post<ReadingSchedule[]>(
-      `/groups/${groupId}/books/${bookId}/schedule/`,
-      { num_meetings: numMeetings }
-    );
-    return data;
-  },
-
-  async deleteSchedule(groupId: number, bookId: number): Promise<void> {
-    await api.delete(`/groups/${groupId}/books/${bookId}/schedule/`);
-  },
-
-  // ---- Progress ----
-
-  async getProgress(
-    groupId: number,
-    bookId: number
-  ): Promise<MemberProgress[]> {
-    const { data } = await api.get<MemberProgress[]>(
-      `/groups/${groupId}/books/${bookId}/progress/`
-    );
-    return data;
-  },
-
-  async updateProgress(
-    groupId: number,
-    bookId: number,
-    payload: { current_section?: number; completed_sections?: number[] }
-  ): Promise<MemberProgress> {
-    const { data } = await api.patch<MemberProgress>(
-      `/groups/${groupId}/books/${bookId}/progress/`,
-      payload
-    );
     return data;
   },
 };

frontend/src/components/notifications/PaceNotification.tsx

@@ -0,0 +1,119 @@
+import { useEffect, useState } from "react";
+import { useTranslation } from "react-i18n-lite";
+import { groupsApi } from "../api/groups";
+import type { PaceStatus } from "../types/notifications";
+
+interface PaceNotificationProps {
+  ebookId?: number;
+}
+
+export function PaceNotification({ ebookId }: PaceNotificationProps) {
+  const { t } = useTranslation();
+  const [paceItems, setPaceItems] = useState<PaceStatus[]>([]);
+  const [loading, setLoading] = useState(true);
+  const [dismissed, setDismissed] = useState<Set<string>>(new Set());
+
+  useEffect(() => {
+    const load = async () => {
+      try {
+        const data = await groupsApi.getPaceStatus(ebookId);
+        setPaceItems(data);
+      } catch {
+        // Silently fail — notifications are non-critical
+      } finally {
+        setLoading(false);
+      }
+    };
+    void load();
+  }, [ebookId]);
+
+  const handleDismiss = async (meetingId: number, itemEbookId: number) => {
+    const key = `${meetingId}-${itemEbookId}`;
+    setDismissed((prev) => new Set(prev).add(key));
+    try {
+      await groupsApi.dismissPaceNotification(meetingId, itemEbookId);
+    } catch {
+      // Best effort dismissal
+    }
+  };
+
+  if (loading || paceItems.length === 0) return null;
+
+  const visibleItems = paceItems.filter(
+    (p) => !dismissed.has(`${p.meeting_id}-${p.ebook_id}`),
+  );
+  if (visibleItems.length === 0) return null;
+
+  return (
+    <div style={{ display: "flex", flexDirection: "column", gap: 8, padding: "12px 0" }}>
+      {visibleItems.map((item) => {
+        const isBehind = item.status === "behind";
+        const isAhead = item.status === "ahead" || item.status === "completed";
+        const isOnTrack = item.status === "on_track";
+
+        const bgColor = isBehind ? "#fde8e8" : isAhead ? "#d4edda" : "#e8f4fd";
+        const borderColor = isBehind ? "#e74c3c" : isAhead ? "#27ae60" : "#3498db";
+        const textColor = isBehind ? "#a71d2a" : isAhead ? "#155724" : "#0c5460";
+
+        return (
+          <div
+            key={`${item.meeting_id}-${item.ebook_id}`}
+            style={{
+              background: bgColor,
+              border: `1px solid ${borderColor}`,
+              borderRadius: 8,
+              padding: "12px 16px",
+              display: "flex",
+              alignItems: "flex-start",
+              justifyContent: "space-between",
+              gap: 12,
+            }}
+          >
+            <div style={{ flex: 1 }}>
+              <div style={{ fontSize: 14, fontWeight: 600, color: textColor, marginBottom: 4 }}>
+                {isBehind
+                  ? `Behind schedule — catch up ${item.sections_to_catch_up} section${item.sections_to_catch_up !== 1 ? "s" : ""}`
+                  : isOnTrack
+                    ? "On track — keep going!"
+                    : item.status === "completed"
+                      ? "Meeting target completed!"
+                      : "Ahead of schedule — great job!"}
+              </div>
+              <div style={{ fontSize: 13, color: textColor, opacity: 0.85 }}>
+                {item.meeting_title || `Target: ${item.target_section_label || `Section ${item.target_section}`}`}
+                {" — "}
+                {item.ebook_title}
+              </div>
+              <div style={{ fontSize: 12, color: textColor, opacity: 0.7, marginTop: 2 }}>
+                {isBehind
+                  ? `Currently at section ${item.current_section}, need section ${item.target_section}`
+                  : `Section ${item.current_section} of ${item.target_section}`}
+                {item.days_until_meeting > 0 &&
+                  ` · ${item.days_until_meeting} day${item.days_until_meeting !== 1 ? "s" : ""} until meeting`}
+                {item.days_until_meeting === 0 && " · Meeting today"}
+              </div>
+            </div>
+            <button
+              type="button"
+              onClick={() => handleDismiss(item.meeting_id, item.ebook_id)}
+              style={{
+                background: "none",
+                border: "none",
+                color: textColor,
+                fontSize: 20,
+                cursor: "pointer",
+                padding: "0 4px",
+                lineHeight: 1,
+                opacity: 0.6,
+                flexShrink: 0,
+              }}
+              title="Dismiss"
+            >
+              ×
+            </button>
+          </div>
+        );
+      })}
+    </div>
+  );
+}

frontend/src/components/notifications/ReadingPaceBanner.tsx

@@ -0,0 +1,71 @@
+import { useEffect, useState } from "react";
+import { groupsApi } from "../../api/groups";
+import type { PaceStatus } from "../../types/notifications";
+
+interface ReadingPaceBannerProps {
+  ebookId: number;
+  currentSection: number;
+}
+
+export function ReadingPaceBanner({ ebookId, currentSection }: ReadingPaceBannerProps) {
+  const [paceItems, setPaceItems] = useState<PaceStatus[]>([]);
+
+  useEffect(() => {
+    const load = async () => {
+      try {
+        const data = await groupsApi.getPaceStatus(ebookId);
+        setPaceItems(data);
+      } catch {
+        // Silently fail
+      }
+    };
+    void load();
+  }, [ebookId, currentSection]);
+
+  if (paceItems.length === 0) return null;
+
+  // Only show if user is one section away from target
+  const relevantItems = paceItems.filter(
+    (p) => Math.abs(p.target_section - p.current_section) <= 1 && p.status !== "completed",
+  );
+
+  if (relevantItems.length === 0) return null;
+
+  return (
+    <div
+      style={{
+        background: "linear-gradient(135deg, #667eea 0%, #764ba2 100%)",
+        color: "#fff",
+        padding: "10px 16px",
+        fontSize: 13,
+        fontWeight: 500,
+        textAlign: "center",
+        display: "flex",
+        alignItems: "center",
+        justifyContent: "center",
+        gap: 8,
+        flexWrap: "wrap",
+        position: "sticky",
+        top: 0,
+        zIndex: 10,
+      }}
+    >
+      {relevantItems.map((item) => {
+        const isAlmostThere = item.sections_to_catch_up === 1;
+        const isAtTarget = item.sections_to_catch_up === 0;
+
+        return (
+          <span key={item.meeting_id}>
+            {isAtTarget
+              ? `You've reached the target for ${item.meeting_title || `Section ${item.target_section}`}!`
+              : isAlmostThere
+                ? `Almost there! Just 1 section to go for ${item.meeting_title || `Section ${item.target_section}`}.`
+                : `You should be on ${item.target_section_label || `Section ${item.target_section}`} by the upcoming meeting.`}
+            {item.days_until_meeting > 0 &&
+              ` (${item.days_until_meeting} day${item.days_until_meeting !== 1 ? "s" : ""} left)`}
+          </span>
+        );
+      })}
+    </div>
+  );
+}

frontend/src/components/reader/EpubReadingView.tsx

@@ -22,6 +22,7 @@ import { SelectionPopover } from "./SelectionPopover";
 import { BookMarkersPanel } from "./BookMarkersPanel";
 import { BookmarkReaderRail } from "./BookmarkReaderRail";
 import { ResumeReadingButton } from "./ResumeReadingButton";
+import { ReadingPaceBanner } from "../notifications/ReadingPaceBanner";
 import type { MarkerEntry } from "@/types";
 
 const ReaderToolbar = lazy(() => import("./ReaderToolbar"));
@@ -130,6 +131,10 @@ export function EpubReadingView({ book, bookId, initialEpubLocation }: EpubReadi
 
   return (
     <ReaderSuspenseShell theme={settings.theme}>
+        <ReadingPaceBanner
+          ebookId={bookId}
+          currentSection={tocItems.length > 0 ? Math.max(1, Math.ceil((progress / 100) * tocItems.length)) : 0}
+        />
         <ReaderToolbar
           bookTitle={book.title}
           chapterTitle={chapterTitle || t("reader.reading")}

frontend/src/components/reader/PdfReadingView.tsx

@@ -24,6 +24,7 @@ import { BookmarkReaderRail } from "./BookmarkReaderRail";
 import { ResumeReadingButton } from "./ResumeReadingButton";
 import { PdfLimitationsNotice } from "./PdfLimitationsNotice";
 import { PdfViewer } from "./PdfViewer";
+import { ReadingPaceBanner } from "../notifications/ReadingPaceBanner";
 import type { MarkerEntry } from "@/types";
 
 const ReaderToolbar = lazy(() => import("./ReaderToolbar"));
@@ -170,6 +171,10 @@ export function PdfReadingView({ book, bookId, initialAnchor }: PdfReadingViewPr
 
   return (
     <ReaderSuspenseShell theme={settings.theme}>
+        <ReadingPaceBanner
+          ebookId={bookId}
+          currentSection={currentPage}
+        />
         <ReaderToolbar
           bookTitle={book.title}
           chapterTitle={chapterTitle || t("reader.reading")}

frontend/src/locales/en-US.ts

@@ -245,54 +245,6 @@ const enUS = {
     home: "Home",
     bookmarksNotes: "Bookmarks & Notes",
   },
-  groups: {
-    title: "Reading Groups",
-    createGroup: "Create Group",
-    create: "Create",
-    cancel: "Cancel",
-    groupName: "Group Name",
-    groupNamePlaceholder: "Enter group name",
-    description: "Description",
-    descriptionPlaceholder: "What is this group about?",
-    optional: "Optional",
-    noGroups: "No groups yet",
-    noGroupsHint: "Create a reading group to start reading together!",
-    members: "Members",
-    admin: "Admin",
-    addMember: "Add Member",
-    memberIdPlaceholder: "Enter user ID",
-    add: "Add",
-    remove: "Remove",
-    books: "Group Books",
-    uploadEpub: "Upload EPUB",
-    selectEbook: "Select an EPUB to share with the group",
-    noEpubBooks: "No EPUB files uploaded yet",
-    uploadFirst: "Upload an EPUB first",
-    confirmUpload: "Confirm Upload",
-    noBooks: "No books in this group yet",
-    sections: "Sections",
-    schedule: "Schedule",
-    progress: "Progress",
-    detectSections: "Auto-Detect Sections",
-    mergeSections: "Merge Sections",
-    selectSectionsHint: "Click sections to select for merging",
-    merge: "Merge",
-    clear: "Clear",
-    split: "Split",
-    splitInto: "Split into",
-    parts: "parts",
-    splitBtn: "Split",
-    noSections: "No sections detected yet",
-    noSectionsHint: 'Click "Auto-Detect Sections" to parse the EPUB chapters into reading sections.',
-    readingSchedule: "Reading Schedule",
-    generateSchedule: "Generate Schedule",
-    noSchedule: "No schedule generated yet",
-    noScheduleHint: "Detect sections first, then generate a reading schedule for your group.",
-    meeting: "Meeting",
-    memberProgress: "Member Progress",
-    noProgress: "No progress data yet",
-    noProgressHint: "Members will show progress once they start reading.",
-  },
 } as const;
 
 export default enUS;

frontend/src/locales/es-ES.ts

@@ -247,54 +247,6 @@ const esES: Locale = {
     home: "Inicio",
     bookmarksNotes: "Marcadores y notas",
   },
-  groups: {
-    title: "Grupos de Lectura",
-    createGroup: "Crear Grupo",
-    create: "Crear",
-    cancel: "Cancelar",
-    groupName: "Nombre del Grupo",
-    groupNamePlaceholder: "Ingresa el nombre del grupo",
-    description: "Descripción",
-    descriptionPlaceholder: "¿De qué trata este grupo?",
-    optional: "Opcional",
-    noGroups: "Aún no hay grupos",
-    noGroupsHint: "¡Crea un grupo de lectura para leer juntos!",
-    members: "Miembros",
-    admin: "Admin",
-    addMember: "Agregar Miembro",
-    memberIdPlaceholder: "Ingresa ID de usuario",
-    add: "Agregar",
-    remove: "Eliminar",
-    books: "Libros del Grupo",
-    uploadEpub: "Subir EPUB",
-    selectEbook: "Selecciona un EPUB para compartir con el grupo",
-    noEpubBooks: "No hay archivos EPUB subidos aún",
-    uploadFirst: "Sube un EPUB primero",
-    confirmUpload: "Confirmar Subida",
-    noBooks: "No hay libros en este grupo aún",
-    sections: "Secciones",
-    schedule: "Calendario",
-    progress: "Progreso",
-    detectSections: "Auto-Detectar Secciones",
-    mergeSections: "Fusionar Secciones",
-    selectSectionsHint: "Haz clic en las secciones para seleccionar y fusionar",
-    merge: "Fusionar",
-    clear: "Limpiar",
-    split: "Dividir",
-    splitInto: "Dividir en",
-    parts: "partes",
-    splitBtn: "Dividir",
-    noSections: "No se detectaron secciones",
-    noSectionsHint: 'Haz clic en "Auto-Detectar Secciones" para analizar los capítulos del EPUB.',
-    readingSchedule: "Calendario de Lectura",
-    generateSchedule: "Generar Calendario",
-    noSchedule: "No hay calendario generado",
-    noScheduleHint: "Detecta secciones primero, luego genera un calendario de lectura para tu grupo.",
-    meeting: "Reunión",
-    memberProgress: "Progreso de Miembros",
-    noProgress: "Sin datos de progreso",
-    noProgressHint: "Los miembros mostrarán progreso cuando comiencen a leer.",
-  },
 };
 
 export default esES;

frontend/src/pages/GroupBookPage.tsx

@@ -1,426 +0,0 @@
-import React, { useCallback, useEffect, useState } from "react";
-import { useNavigate, useParams } from "react-router-dom";
-import { useTranslation } from "react-i18n-lite";
-import { groupsApi } from "../api/groups";
-import { getApiErrorMessage } from "../api/errors";
-import type {
-  GroupBookDetail,
-  ReadingSchedule,
-  Section,
-  MemberProgress,
-} from "../types/group";
-
-export function GroupBookPage() {
-  const { t } = useTranslation();
-  const navigate = useNavigate();
-  const { groupId, bookId } = useParams<{ groupId: string; bookId: string }>();
-
-  const [book, setBook] = useState<GroupBookDetail | null>(null);
-  const [sections, setSections] = useState<Section[]>([]);
-  const [schedules, setSchedules] = useState<ReadingSchedule[]>([]);
-  const [progress, setProgress] = useState<MemberProgress[]>([]);
-  const [loading, setLoading] = useState(true);
-  const [error, setError] = useState<string | null>(null);
-  const [tab, setTab] = useState<"sections" | "schedule" | "progress">("sections");
-
-  // Merge state
-  const [selectedForMerge, setSelectedForMerge] = useState<number[]>([]);
-  const [splitSectionId, setSplitSectionId] = useState<number | null>(null);
-  const [splitAt, setSplitAt] = useState(2);
-
-  const gId = Number(groupId);
-  const bId = Number(bookId);
-
-  const loadData = useCallback(async () => {
-    if (!gId || !bId) return;
-    setLoading(true);
-    try {
-      const [bookData, schedData, progData] = await Promise.all([
-        groupsApi.getGroupBook(gId, bId),
-        groupsApi.getSchedule(gId, bId).catch(() => [] as ReadingSchedule[]),
-        groupsApi.getProgress(gId, bId).catch(() => [] as MemberProgress[]),
-      ]);
-      setBook(bookData);
-      setSections(bookData.sections ?? []);
-      setSchedules(schedData);
-      setProgress(progData);
-    } catch (err) {
-      setError(getApiErrorMessage(err, "Failed to load book"));
-    } finally {
-      setLoading(false);
-    }
-  }, [gId, bId]);
-
-  useEffect(() => {
-    loadData();
-  }, [loadData]);
-
-  const handleDetectSections = async () => {
-    if (!gId || !bId) return;
-    try {
-      const newSections = await groupsApi.detectSections(gId, bId);
-      setSections(newSections);
-    } catch (err) {
-      setError(getApiErrorMessage(err, "Failed to detect sections"));
-    }
-  };
-
-  const handleMerge = async () => {
-    if (selectedForMerge.length < 2 || !gId || !bId) return;
-    try {
-      await groupsApi.adjustSections(gId, bId, {
-        operation: "merge",
-        section_ids: selectedForMerge,
-      });
-      setSelectedForMerge([]);
-      await loadData();
-    } catch (err) {
-      setError(getApiErrorMessage(err, "Failed to merge sections"));
-    }
-  };
-
-  const handleSplit = async () => {
-    if (!splitSectionId || !gId || !bId) return;
-    try {
-      await groupsApi.adjustSections(gId, bId, {
-        operation: "split",
-        section_ids: [splitSectionId],
-        split_at: splitAt,
-      });
-      setSplitSectionId(null);
-      await loadData();
-    } catch (err) {
-      setError(getApiErrorMessage(err, "Failed to split section"));
-    }
-  };
-
-  const handleGenerateSchedule = async () => {
-    if (!gId || !bId) return;
-    try {
-      const newSched = await groupsApi.generateSchedule(gId, bId, 4);
-      setSchedules(newSched);
-    } catch (err) {
-      setError(getApiErrorMessage(err, "Failed to generate schedule"));
-    }
-  };
-
-  const toggleMergeSelect = (id: number) => {
-    setSelectedForMerge((prev) =>
-      prev.includes(id) ? prev.filter((s) => s !== id) : [...prev, id]
-    );
-  };
-
-  const formatMinutes = (mins: number): string => {
-    if (mins < 60) return `${mins}m`;
-    const h = Math.floor(mins / 60);
-    const m = mins % 60;
-    return m > 0 ? `${h}h ${m}m` : `${h}h`;
-  };
-
-  if (loading) {
-    return (
-      <div style={{ maxWidth: 800, margin: "0 auto", padding: 16, minHeight: "100vh", background: "#f8f9fa" }}>
-        <p style={{ textAlign: "center", color: "#888", padding: 40 }}>{t("common.loading")}</p>
-      </div>
-    );
-  }
-
-  if (!book) {
-    return (
-      <div style={{ maxWidth: 800, margin: "0 auto", padding: 16, minHeight: "100vh", background: "#f8f9fa" }}>
-        <p style={{ textAlign: "center", color: "#e74c3c", padding: 40 }}>Book not found</p>
-        <button onClick={() => navigate(`/groups/${groupId}`)} style={{ display: "block", margin: "0 auto" }}>← Back</button>
-      </div>
-    );
-  }
-
-  return (
-    <div style={{ maxWidth: 800, margin: "0 auto", padding: 16, minHeight: "100vh", background: "#f8f9fa" }}>
-      {/* Header */}
-      <header style={{ display: "flex", justifyContent: "space-between", alignItems: "center", padding: "16px 0", borderBottom: "1px solid #eee", marginBottom: 20 }}>
-        <div>
-          <h1 style={{ fontSize: 24, fontWeight: 700, color: "#1a1a2e", margin: 0 }}>{book.title}</h1>
-          <p style={{ margin: 4, fontSize: 13, color: "#888" }}>
-            {book.ebook.author && `by ${book.ebook.author} · `}
-            {book.ebook.page_count} chapters · {book.ebook.format.toUpperCase()}
-          </p>
-        </div>
-        <button onClick={() => navigate(`/groups/${groupId}`)} style={{ padding: "8px 16px", borderRadius: 6, border: "1px solid #ddd", background: "#fff", cursor: "pointer", fontSize: 14 }}>
-          ← {t("common.back")}
-        </button>
-      </header>
-
-      {error && (
-        <div style={{ background: "#fde8e8", padding: 12, borderRadius: 6, color: "#e74c3c", fontSize: 14, marginBottom: 16 }}>
-          {error}
-          <button onClick={() => setError(null)} style={{ marginLeft: 12, background: "none", border: "none", cursor: "pointer", fontWeight: 600 }}>✕</button>
-        </div>
-      )}
-
-      {/* Tabs */}
-      <div style={{ display: "flex", gap: 4, marginBottom: 20, background: "#eee", borderRadius: 8, padding: 4 }}>
-        {(["sections", "schedule", "progress"] as const).map((t) => (
-          <button
-            key={t}
-            onClick={() => setTab(t)}
-            style={{
-              flex: 1, padding: "10px 16px", borderRadius: 6, border: "none",
-              fontSize: 14, fontWeight: 600, cursor: "pointer",
-              background: tab === t ? "#fff" : "transparent",
-              color: tab === t ? "#1a1a2e" : "#888",
-              boxShadow: tab === t ? "0 1px 4px rgba(0,0,0,0.1)" : "none",
-            }}
-          >
-            {t === "sections" ? t("groups.sections") : t === "schedule" ? t("groups.schedule") : t("groups.progress")}
-          </button>
-        ))}
-      </div>
-
-      {/* Sections Tab */}
-      {tab === "sections" && (
-        <section>
-          <div style={{ display: "flex", justifyContent: "space-between", alignItems: "center", marginBottom: 16 }}>
-            <h2 style={{ fontSize: 18, fontWeight: 600, color: "#1a1a2e", margin: 0 }}>
-              {sections.length} {t("groups.sections")}
-            </h2>
-            <div style={{ display: "flex", gap: 8 }}>
-              <button
-                onClick={handleDetectSections}
-                style={{ padding: "8px 16px", borderRadius: 6, border: "none", background: "#1a1a2e", color: "#fff", fontSize: 13, fontWeight: 600, cursor: "pointer" }}
-              >
-                {t("groups.detectSections")}
-              </button>
-            </div>
-          </div>
-
-          {/* Merge controls */}
-          <div style={{ background: "#fff", padding: 16, borderRadius: 10, marginBottom: 12, boxShadow: "0 1px 4px rgba(0,0,0,0.06)" }}>
-            <div style={{ display: "flex", alignItems: "center", gap: 10, flexWrap: "wrap" }}>
-              <span style={{ fontSize: 14, fontWeight: 600, color: "#555" }}>{t("groups.mergeSections")}:</span>
-              <span style={{ fontSize: 13, color: "#888" }}>
-                {selectedForMerge.length === 0
-                  ? t("groups.selectSectionsHint")
-                  : `${selectedForMerge.length} selected`}
-              </span>
-              {selectedForMerge.length >= 2 && (
-                <button
-                  onClick={handleMerge}
-                  style={{ padding: "6px 14px", borderRadius: 6, border: "none", background: "#27ae60", color: "#fff", fontSize: 13, fontWeight: 600, cursor: "pointer" }}
-                >
-                  {t("groups.merge")}
-                </button>
-              )}
-              {selectedForMerge.length > 0 && (
-                <button
-                  onClick={() => setSelectedForMerge([])}
-                  style={{ padding: "6px 12px", borderRadius: 6, border: "1px solid #ddd", background: "#fff", fontSize: 13, cursor: "pointer" }}
-                >
-                  {t("groups.clear")}
-                </button>
-              )}
-            </div>
-          </div>
-
-          {sections.length === 0 ? (
-            <div style={{ textAlign: "center", padding: 40, color: "#888" }}>
-              <p style={{ fontSize: 16 }}>{t("groups.noSections")}</p>
-              <p style={{ fontSize: 14 }}>{t("groups.noSectionsHint")}</p>
-            </div>
-          ) : (
-            <div style={{ display: "flex", flexDirection: "column", gap: 10 }}>
-              {sections.map((section) => (
-                <div
-                  key={section.id}
-                  style={{
-                    background: selectedForMerge.includes(section.id) ? "#e8f0fe" : "#fff",
-                    border: selectedForMerge.includes(section.id) ? "2px solid #1a1a2e" : "1px solid #eee",
-                    padding: 16, borderRadius: 10, cursor: "pointer",
-                    boxShadow: "0 1px 4px rgba(0,0,0,0.06)",
-                    transition: "all 0.15s",
-                  }}
-                  onClick={() => toggleMergeSelect(section.id)}
-                >
-                  <div style={{ display: "flex", justifyContent: "space-between", alignItems: "flex-start" }}>
-                    <div style={{ flex: 1 }}>
-                      <div style={{ display: "flex", alignItems: "center", gap: 8 }}>
-                        <span style={{
-                          background: "#1a1a2e", color: "#fff", borderRadius: 20,
-                          width: 26, height: 26, display: "flex", alignItems: "center", justifyContent: "center",
-                          fontSize: 13, fontWeight: 700, flexShrink: 0,
-                        }}>
-                          {section.order}
-                        </span>
-                        <h3 style={{ margin: 0, fontSize: 15, fontWeight: 600, color: "#1a1a2e" }}>{section.title}</h3>
-                      </div>
-                      <p style={{ margin: "6px 0 0 34px", fontSize: 13, color: "#888" }}>
-                        Ch. {section.start_chapter_index}–{section.end_chapter_index - 1} · ~{formatMinutes(section.estimated_reading_minutes)} reading time
-                      </p>
-                    </div>
-                    <button
-                      onClick={(e) => {
-                        e.stopPropagation();
-                        setSplitSectionId(splitSectionId === section.id ? null : section.id);
-                      }}
-                      style={{
-                        padding: "4px 10px", borderRadius: 4, border: "1px solid #ddd",
-                        background: splitSectionId === section.id ? "#1a1a2e" : "#fff",
-                        color: splitSectionId === section.id ? "#fff" : "#666",
-                        fontSize: 12, cursor: "pointer", flexShrink: 0,
-                      }}
-                    >
-                      {t("groups.split")}
-                    </button>
-                  </div>
-                  {splitSectionId === section.id && (
-                    <div
-                      style={{ marginTop: 10, padding: 10, background: "#f8f9fa", borderRadius: 6, display: "flex", alignItems: "center", gap: 8 }}
-                      onClick={(e) => e.stopPropagation()}
-                    >
-                      <span style={{ fontSize: 13 }}>{t("groups.splitInto")}</span>
-                      <input
-                        type="number"
-                        value={splitAt}
-                        min={2}
-                        max={10}
-                        onChange={(e) => setSplitAt(Number(e.target.value))}
-                        style={{ width: 50, padding: "4px 8px", borderRadius: 4, border: "1px solid #ddd", fontSize: 13, textAlign: "center" }}
-                      />
-                      <span style={{ fontSize: 13 }}>{t("groups.parts")}</span>
-                      <button
-                        onClick={handleSplit}
-                        style={{ padding: "4px 12px", borderRadius: 4, border: "none", background: "#1a1a2e", color: "#fff", fontSize: 12, cursor: "pointer" }}
-                      >
-                        {t("groups.splitBtn")}
-                      </button>
-                    </div>
-                  )}
-                </div>
-              ))}
-            </div>
-          )}
-        </section>
-      )}
-
-      {/* Schedule Tab */}
-      {tab === "schedule" && (
-        <section>
-          <div style={{ display: "flex", justifyContent: "space-between", alignItems: "center", marginBottom: 16 }}>
-            <h2 style={{ fontSize: 18, fontWeight: 600, color: "#1a1a2e", margin: 0 }}>
-              {t("groups.readingSchedule")}
-            </h2>
-            <button
-              onClick={handleGenerateSchedule}
-              style={{ padding: "8px 16px", borderRadius: 6, border: "none", background: "#1a1a2e", color: "#fff", fontSize: 13, fontWeight: 600, cursor: "pointer" }}
-            >
-              {t("groups.generateSchedule")}
-            </button>
-          </div>
-
-          {schedules.length === 0 ? (
-            <div style={{ textAlign: "center", padding: 40, color: "#888" }}>
-              <p style={{ fontSize: 16 }}>{t("groups.noSchedule")}</p>
-              <p style={{ fontSize: 14 }}>{t("groups.noScheduleHint")}</p>
-            </div>
-          ) : (
-            <div style={{ display: "flex", flexDirection: "column", gap: 16 }}>
-              {schedules.map((s) => (
-                <div
-                  key={s.id}
-                  style={{ background: "#fff", padding: 20, borderRadius: 12, boxShadow: "0 2px 8px rgba(0,0,0,0.06)" }}
-                >
-                  <div style={{ display: "flex", justifyContent: "space-between", alignItems: "center", marginBottom: 12 }}>
-                    <div>
-                      <h3 style={{ margin: 0, fontSize: 17, fontWeight: 700, color: "#1a1a2e" }}>
-                        {t("groups.meeting")} {s.meeting_number}
-                      </h3>
-                      <p style={{ margin: "4px 0 0", fontSize: 13, color: "#888" }}>
-                        Week of {new Date(s.week_date).toLocaleDateString("en-US", { month: "long", day: "numeric", year: "numeric" })}
-                      </p>
-                    </div>
-                    <span style={{
-                      background: "#f0f0f0", padding: "6px 12px", borderRadius: 20,
-                      fontSize: 13, fontWeight: 600, color: "#555",
-                    }}>
-                      {s.section_details.reduce((sum, sec) => sum + sec.estimated_reading_minutes, 0) > 0
-                        ? `~${formatMinutes(s.section_details.reduce((sum, sec) => sum + sec.estimated_reading_minutes, 0))}`
-                        : ""}
-                    </span>
-                  </div>
-                  <div style={{ display: "flex", flexDirection: "column", gap: 6 }}>
-                    {s.section_details.map((sec) => (
-                      <div
-                        key={sec.id}
-                        style={{
-                          display: "flex", alignItems: "center", gap: 10, padding: "8px 12px",
-                          background: "#f8f9fa", borderRadius: 6, fontSize: 14,
-                        }}
-                      >
-                        <span style={{
-                          background: "#1a1a2e", color: "#fff", borderRadius: 12,
-                          width: 22, height: 22, display: "flex", alignItems: "center", justifyContent: "center",
-                          fontSize: 11, fontWeight: 700, flexShrink: 0,
-                        }}>
-                          {sec.order}
-                        </span>
-                        <span style={{ flex: 1 }}>{sec.title}</span>
-                        <span style={{ fontSize: 12, color: "#999" }}>{formatMinutes(sec.estimated_reading_minutes)}</span>
-                      </div>
-                    ))}
-                  </div>
-                </div>
-              ))}
-            </div>
-          )}
-        </section>
-      )}
-
-      {/* Progress Tab */}
-      {tab === "progress" && (
-        <section>
-          <h2 style={{ fontSize: 18, fontWeight: 600, color: "#1a1a2e", margin: "0 0 16px" }}>
-            {t("groups.memberProgress")}
-          </h2>
-          {progress.length === 0 ? (
-            <div style={{ textAlign: "center", padding: 40, color: "#888" }}>
-              <p style={{ fontSize: 16 }}>{t("groups.noProgress")}</p>
-              <p style={{ fontSize: 14 }}>{t("groups.noProgressHint")}</p>
-            </div>
-          ) : (
-            <div style={{ display: "flex", flexDirection: "column", gap: 10 }}>
-              {progress.map((p) => {
-                const totalSections = sections.length;
-                const completed = p.completed_sections.length;
-                const pct = totalSections > 0 ? Math.round((completed / totalSections) * 100) : 0;
-                return (
-                  <div
-                    key={p.id}
-                    style={{ background: "#fff", padding: 16, borderRadius: 10, boxShadow: "0 1px 4px rgba(0,0,0,0.06)" }}
-                  >
-                    <div style={{ display: "flex", justifyContent: "space-between", alignItems: "center", marginBottom: 8 }}>
-                      <span style={{ fontSize: 15, fontWeight: 600 }}>{p.user_email}</span>
-                      <span style={{ fontSize: 13, color: "#888" }}>{completed}/{totalSections} · {pct}%</span>
-                    </div>
-                    <div style={{ height: 6, background: "#eee", borderRadius: 3, overflow: "hidden" }}>
-                      <div
-                        style={{
-                          height: "100%", borderRadius: 3,
-                          background: "linear-gradient(90deg, #27ae60, #2ecc71)",
-                          width: `${pct}%`, transition: "width 0.3s",
-                        }}
-                      />
-                    </div>
-                    {p.current_section_title && (
-                      <p style={{ margin: "8px 0 0", fontSize: 13, color: "#888" }}>
-                        Currently: {p.current_section_title}
-                      </p>
-                    )}
-                  </div>
-                );
-              })}
-            </div>
-          )}
-        </section>
-      )}
-    </div>
-  );
-}

frontend/src/pages/GroupDetailPage.tsx

@@ -1,300 +0,0 @@
-import React, { useCallback, useEffect, useState } from "react";
-import { useNavigate, useParams } from "react-router-dom";
-import { useTranslation } from "react-i18n-lite";
-import { groupsApi } from "../api/groups";
-import { booksApi } from "../api/books";
-import { getApiErrorMessage } from "../api/errors";
-import type { ReadingGroupDetail, GroupBook, GroupBookDetail } from "../types/group";
-import type { EBookListItem } from "../types/book";
-
-export function GroupDetailPage() {
-  const { t } = useTranslation();
-  const navigate = useNavigate();
-  const { groupId } = useParams<{ groupId: string }>();
-  const [group, setGroup] = useState<ReadingGroupDetail | null>(null);
-  const [books, setBooks] = useState<GroupBook[]>([]);
-  const [loading, setLoading] = useState(true);
-  const [error, setError] = useState<string | null>(null);
-
-  // Upload state
-  const [showUpload, setShowUpload] = useState(false);
-  const [ebooks, setEbooks] = useState<EBookListItem[]>([]);
-  const [selectedEbookId, setSelectedEbookId] = useState<number | null>(null);
-  const [uploading, setUploading] = useState(false);
-
-  // Add member state
-  const [showAddMember, setShowAddMember] = useState(false);
-  const [memberEmail, setMemberEmail] = useState("");
-  const [adding, setAdding] = useState(false);
-
-  const id = Number(groupId);
-
-  const loadData = useCallback(async () => {
-    if (!id) return;
-    setLoading(true);
-    try {
-      const [groupData, bookData] = await Promise.all([
-        groupsApi.getGroup(id),
-        groupsApi.listGroupBooks(id),
-      ]);
-      setGroup(groupData);
-      setBooks(bookData);
-    } catch (err) {
-      setError(getApiErrorMessage(err, "Failed to load group"));
-    } finally {
-      setLoading(false);
-    }
-  }, [id]);
-
-  useEffect(() => {
-    loadData();
-  }, [loadData]);
-
-  const handleUploadClick = async () => {
-    setShowUpload(true);
-    try {
-      const ebookList = await booksApi.getEBooks();
-      setEbooks(ebookList.filter((e) => e.format === "epub"));
-    } catch {
-      // Ebook list fetch failed silently
-    }
-  };
-
-  const handleUpload = async () => {
-    if (!selectedEbookId || !id) return;
-    setUploading(true);
-    try {
-      const created = await groupsApi.createGroupBook(id, { ebook_id: selectedEbookId });
-      setShowUpload(false);
-      setSelectedEbookId(null);
-      await loadData();
-    } catch (err) {
-      setError(getApiErrorMessage(err, "Failed to upload book to group"));
-    } finally {
-      setUploading(false);
-    }
-  };
-
-  const handleAddMember = async (e: React.FormEvent) => {
-    e.preventDefault();
-    if (!memberEmail.trim() || !id) return;
-    setAdding(true);
-    try {
-      // Note: In a real implementation, we'd look up user by email.
-      // For now this requires user_id. Email lookup would be an enhancement.
-      await groupsApi.addMember(id, { user_id: Number(memberEmail) });
-      setShowAddMember(false);
-      setMemberEmail("");
-      await loadData();
-    } catch (err) {
-      setError(getApiErrorMessage(err, "Failed to add member. Please use a valid user ID."));
-    } finally {
-      setAdding(false);
-    }
-  };
-
-  const handleRemoveMember = async (userId: number) => {
-    if (!id) return;
-    try {
-      await groupsApi.removeMember(id, { user_id: userId });
-      await loadData();
-    } catch (err) {
-      setError(getApiErrorMessage(err, "Failed to remove member"));
-    }
-  };
-
-  if (loading) {
-    return (
-      <div style={{ maxWidth: 700, margin: "0 auto", padding: 16, minHeight: "100vh", background: "#f8f9fa" }}>
-        <p style={{ textAlign: "center", color: "#888", padding: 40 }}>{t("common.loading")}</p>
-      </div>
-    );
-  }
-
-  if (!group) {
-    return (
-      <div style={{ maxWidth: 700, margin: "0 auto", padding: 16, minHeight: "100vh", background: "#f8f9fa" }}>
-        <p style={{ textAlign: "center", color: "#e74c3c", padding: 40 }}>Group not found</p>
-        <button onClick={() => navigate("/groups")} style={{ display: "block", margin: "0 auto" }}>← Back to Groups</button>
-      </div>
-    );
-  }
-
-  return (
-    <div style={{ maxWidth: 700, margin: "0 auto", padding: 16, minHeight: "100vh", background: "#f8f9fa" }}>
-      <header style={{ display: "flex", justifyContent: "space-between", alignItems: "center", padding: "16px 0", borderBottom: "1px solid #eee", marginBottom: 20 }}>
-        <div>
-          <h1 style={{ fontSize: 24, fontWeight: 700, color: "#1a1a2e", margin: 0 }}>{group.name}</h1>
-          {group.description && <p style={{ margin: "4px 0 0", fontSize: 14, color: "#666" }}>{group.description}</p>}
-        </div>
-        <button onClick={() => navigate("/groups")} style={{ padding: "8px 16px", borderRadius: 6, border: "1px solid #ddd", background: "#fff", cursor: "pointer", fontSize: 14 }}>
-          ← {t("common.back")}
-        </button>
-      </header>
-
-      {error && (
-        <div style={{ background: "#fde8e8", padding: 12, borderRadius: 6, color: "#e74c3c", fontSize: 14, marginBottom: 16 }}>
-          {error}
-          <button onClick={() => setError(null)} style={{ marginLeft: 12, background: "none", border: "none", cursor: "pointer", fontWeight: 600 }}>✕</button>
-        </div>
-      )}
-
-      {/* Members Section */}
-      <section style={{ background: "#fff", padding: 20, borderRadius: 12, marginBottom: 20, boxShadow: "0 2px 8px rgba(0,0,0,0.06)" }}>
-        <div style={{ display: "flex", justifyContent: "space-between", alignItems: "center", marginBottom: 12 }}>
-          <h2 style={{ fontSize: 18, fontWeight: 600, color: "#1a1a2e", margin: 0 }}>{t("groups.members")} ({group.members.length})</h2>
-          <button
-            onClick={() => setShowAddMember(!showAddMember)}
-            style={{ padding: "6px 14px", borderRadius: 6, border: "1px solid #ddd", background: "#fff", cursor: "pointer", fontSize: 13 }}
-          >
-            {showAddMember ? t("groups.cancel") : `+ ${t("groups.addMember")}`}
-          </button>
-        </div>
-        {showAddMember && (
-          <form onSubmit={handleAddMember} style={{ display: "flex", gap: 8, marginBottom: 12 }}>
-            <input
-              type="text"
-              value={memberEmail}
-              onChange={(e) => setMemberEmail(e.target.value)}
-              placeholder={t("groups.memberIdPlaceholder")}
-              style={{ flex: 1, padding: "8px 12px", borderRadius: 6, border: "1px solid #ddd", fontSize: 14, outline: "none" }}
-            />
-            <button
-              type="submit"
-              disabled={adding}
-              style={{ padding: "8px 16px", borderRadius: 6, border: "none", background: "#1a1a2e", color: "#fff", fontSize: 14, cursor: "pointer", opacity: adding ? 0.6 : 1 }}
-            >
-              {t("groups.add")}
-            </button>
-          </form>
-        )}
-        <div style={{ display: "flex", flexDirection: "column", gap: 8 }}>
-          {group.members.map((m) => (
-            <div key={m.id} style={{ display: "flex", justifyContent: "space-between", alignItems: "center", padding: "8px 0", borderBottom: "1px solid #f0f0f0" }}>
-              <div>
-                <span style={{ fontSize: 14, fontWeight: 500 }}>{m.user_email}</span>
-                <span style={{ marginLeft: 8, fontSize: 12, color: m.role === "admin" ? "#e67e22" : "#999", background: m.role === "admin" ? "#fef3e2" : "#f0f0f0", padding: "2px 8px", borderRadius: 4 }}>
-                  {m.role}
-                </span>
-              </div>
-              {m.role !== "admin" && (
-                <button
-                  onClick={() => handleRemoveMember(m.user)}
-                  style={{ background: "none", border: "none", color: "#e74c3c", cursor: "pointer", fontSize: 13 }}
-                >
-                  {t("groups.remove")}
-                </button>
-              )}
-            </div>
-          ))}
-        </div>
-      </section>
-
-      {/* Books Section */}
-      <section style={{ background: "#fff", padding: 20, borderRadius: 12, boxShadow: "0 2px 8px rgba(0,0,0,0.06)" }}>
-        <div style={{ display: "flex", justifyContent: "space-between", alignItems: "center", marginBottom: 12 }}>
-          <h2 style={{ fontSize: 18, fontWeight: 600, color: "#1a1a2e", margin: 0 }}>{t("groups.books")} ({books.length})</h2>
-          <button
-            onClick={handleUploadClick}
-            style={{ padding: "8px 18px", borderRadius: 8, border: "none", background: "#1a1a2e", color: "#fff", fontSize: 14, fontWeight: 600, cursor: "pointer" }}
-          >
-            {t("groups.uploadEpub")}
-          </button>
-        </div>
-
-        {showUpload && (
-          <div style={{ background: "#f8f9fa", padding: 16, borderRadius: 8, marginBottom: 16 }}>
-            <h3 style={{ fontSize: 15, fontWeight: 600, margin: "0 0 12px" }}>{t("groups.selectEbook")}</h3>
-            {ebooks.length === 0 ? (
-              <div style={{ textAlign: "center", padding: 20, color: "#888" }}>
-                <p>{t("groups.noEpubBooks")}</p>
-                <button onClick={() => navigate("/add")} style={{ marginTop: 8, padding: "8px 16px", borderRadius: 6, border: "1px solid #ddd", background: "#fff", cursor: "pointer", fontSize: 13 }}>
-                  {t("groups.uploadFirst")}
-                </button>
-              </div>
-            ) : (
-              <div>
-                <div style={{ display: "flex", flexDirection: "column", gap: 8, marginBottom: 12, maxHeight: 200, overflowY: "auto" }}>
-                  {ebooks.map((eb) => (
-                    <label
-                      key={eb.id}
-                      style={{
-                        display: "flex", alignItems: "center", gap: 10, padding: "10px 12px",
-                        borderRadius: 8, cursor: "pointer", fontSize: 14,
-                        background: selectedEbookId === eb.id ? "#e8f0fe" : "#fff",
-                        border: selectedEbookId === eb.id ? "2px solid #1a1a2e" : "1px solid #eee",
-                      }}
-                    >
-                      <input
-                        type="radio"
-                        name="ebook"
-                        value={eb.id}
-                        checked={selectedEbookId === eb.id}
-                        onChange={() => setSelectedEbookId(eb.id)}
-                        style={{ accentColor: "#1a1a2e" }}
-                      />
-                      <div>
-                        <strong>{eb.title}</strong>
-                        {eb.author && <span style={{ color: "#888", marginLeft: 8 }}>by {eb.author}</span>}
-                        <span style={{ marginLeft: 8, fontSize: 12, color: "#aaa" }}>({eb.filename})</span>
-                      </div>
-                    </label>
-                  ))}
-                </div>
-                <div style={{ display: "flex", gap: 8 }}>
-                  <button
-                    onClick={handleUpload}
-                    disabled={!selectedEbookId || uploading}
-                    style={{ padding: "10px 20px", borderRadius: 8, border: "none", background: "#1a1a2e", color: "#fff", fontSize: 14, fontWeight: 600, cursor: uploading ? "default" : "pointer", opacity: uploading ? 0.6 : 1 }}
-                  >
-                    {uploading ? t("common.loading") : t("groups.confirmUpload")}
-                  </button>
-                  <button
-                    onClick={() => setShowUpload(false)}
-                    style={{ padding: "10px 20px", borderRadius: 8, border: "1px solid #ddd", background: "#fff", cursor: "pointer", fontSize: 14 }}
-                  >
-                    {t("groups.cancel")}
-                  </button>
-                </div>
-              </div>
-            )}
-          </div>
-        )}
-
-        {books.length === 0 ? (
-          <p style={{ textAlign: "center", color: "#888", padding: 30 }}>{t("groups.noBooks")}</p>
-        ) : (
-          <div style={{ display: "flex", flexDirection: "column", gap: 10 }}>
-            {books.map((book) => (
-              <div
-                key={book.id}
-                onClick={() => navigate(`/groups/${groupId}/books/${book.id}`)}
-                style={{
-                  display: "flex", justifyContent: "space-between", alignItems: "center",
-                  padding: 16, borderRadius: 10, cursor: "pointer", transition: "background 0.2s",
-                  background: book.status === "active" ? "#f0faf0" : "#fafafa",
-                  border: book.status === "active" ? "2px solid #27ae60" : "1px solid #eee",
-                }}
-                onMouseEnter={(e) => (e.currentTarget.style.background = book.status === "active" ? "#e8f5e9" : "#f5f5f5")}
-                onMouseLeave={(e) => (e.currentTarget.style.background = book.status === "active" ? "#f0faf0" : "#fafafa")}
-              >
-                <div>
-                  <h3 style={{ margin: 0, fontSize: 16, fontWeight: 600, color: "#1a1a2e" }}>
-                    {book.title}
-                    {book.status === "active" && (
-                      <span style={{ marginLeft: 8, fontSize: 11, color: "#27ae60", background: "#e8f5e9", padding: "2px 8px", borderRadius: 4 }}>Active</span>
-                    )}
-                  </h3>
-                  <p style={{ margin: "4px 0 0", fontSize: 13, color: "#888" }}>
-                    {book.section_count} sections · {book.ebook.page_count} chapters · uploaded by {book.uploaded_by_email}
-                  </p>
-                </div>
-                <span style={{ fontSize: 20, color: "#ccc" }}>→</span>
-              </div>
-            ))}
-          </div>
-        )}
-      </section>
-    </div>
-  );
-}

frontend/src/pages/GroupsPage.tsx

@@ -1,162 +0,0 @@
-import React, { useCallback, useEffect, useState } from "react";
-import { useNavigate } from "react-router-dom";
-import { useTranslation } from "react-i18n-lite";
-import { groupsApi } from "../api/groups";
-import { getApiErrorMessage } from "../api/errors";
-import type { ReadingGroup } from "../types/group";
-
-export function GroupsPage() {
-  const { t } = useTranslation();
-  const navigate = useNavigate();
-  const [groups, setGroups] = useState<ReadingGroup[]>([]);
-  const [loading, setLoading] = useState(true);
-  const [error, setError] = useState<string | null>(null);
-  const [showCreate, setShowCreate] = useState(false);
-  const [newName, setNewName] = useState("");
-  const [newDesc, setNewDesc] = useState("");
-  const [creating, setCreating] = useState(false);
-
-  const loadGroups = useCallback(async () => {
-    setLoading(true);
-    try {
-      const data = await groupsApi.listGroups();
-      setGroups(data);
-    } catch (err) {
-      setError(getApiErrorMessage(err, "Failed to load groups"));
-    } finally {
-      setLoading(false);
-    }
-  }, []);
-
-  useEffect(() => {
-    loadGroups();
-  }, [loadGroups]);
-
-  const handleCreate = async (e: React.FormEvent) => {
-    e.preventDefault();
-    if (!newName.trim()) return;
-    setCreating(true);
-    try {
-      await groupsApi.createGroup({ name: newName.trim(), description: newDesc.trim() });
-      setShowCreate(false);
-      setNewName("");
-      setNewDesc("");
-      await loadGroups();
-    } catch (err) {
-      setError(getApiErrorMessage(err, "Failed to create group"));
-    } finally {
-      setCreating(false);
-    }
-  };
-
-  return (
-    <div style={{ maxWidth: 700, margin: "0 auto", padding: 16, minHeight: "100vh", background: "#f8f9fa" }}>
-      <header style={{ display: "flex", justifyContent: "space-between", alignItems: "center", padding: "16px 0", borderBottom: "1px solid #eee", marginBottom: 20 }}>
-        <h1 style={{ fontSize: 24, fontWeight: 700, color: "#1a1a2e", margin: 0 }}>{t("groups.title")}</h1>
-        <button
-          type="button"
-          onClick={() => navigate("/")}
-          style={{ padding: "8px 16px", borderRadius: 6, border: "1px solid #ddd", background: "#fff", cursor: "pointer", fontSize: 14 }}
-        >
-          ← {t("common.back")}
-        </button>
-      </header>
-
-      {error && (
-        <div style={{ background: "#fde8e8", padding: 12, borderRadius: 6, color: "#e74c3c", fontSize: 14, marginBottom: 16 }}>
-          {error}
-          <button onClick={() => setError(null)} style={{ marginLeft: 12, background: "none", border: "none", cursor: "pointer", fontWeight: 600 }}>✕</button>
-        </div>
-      )}
-
-      <div style={{ marginBottom: 20 }}>
-        <button
-          type="button"
-          onClick={() => setShowCreate(!showCreate)}
-          style={{
-            padding: "12px 24px", borderRadius: 8, border: "none",
-            background: "#1a1a2e", color: "#fff", fontSize: 15, fontWeight: 600, cursor: "pointer",
-          }}
-        >
-          {showCreate ? t("groups.cancel") : t("groups.createGroup")}
-        </button>
-      </div>
-
-      {showCreate && (
-        <form onSubmit={handleCreate} style={{
-          background: "#fff", padding: 20, borderRadius: 12, marginBottom: 24,
-          boxShadow: "0 2px 8px rgba(0,0,0,0.06)", display: "flex", flexDirection: "column", gap: 14,
-        }}>
-          <div style={{ display: "flex", flexDirection: "column", gap: 6 }}>
-            <label style={{ fontSize: 14, fontWeight: 600, color: "#555" }}>{t("groups.groupName")}</label>
-            <input
-              type="text"
-              value={newName}
-              onChange={(e) => setNewName(e.target.value)}
-              placeholder={t("groups.groupNamePlaceholder")}
-              style={{ padding: "10px 12px", borderRadius: 6, border: "1px solid #ddd", fontSize: 16, outline: "none" }}
-              required
-            />
-          </div>
-          <div style={{ display: "flex", flexDirection: "column", gap: 6 }}>
-            <label style={{ fontSize: 14, fontWeight: 600, color: "#555" }}>{t("groups.description")} ({t("common.optional")})</label>
-            <textarea
-              value={newDesc}
-              onChange={(e) => setNewDesc(e.target.value)}
-              placeholder={t("groups.descriptionPlaceholder")}
-              rows={3}
-              style={{ padding: "10px 12px", borderRadius: 6, border: "1px solid #ddd", fontSize: 15, outline: "none", resize: "vertical" }}
-            />
-          </div>
-          <button
-            type="submit"
-            disabled={creating || !newName.trim()}
-            style={{
-              padding: "10px 20px", borderRadius: 8, border: "none",
-              background: "#1a1a2e", color: "#fff", fontSize: 15, fontWeight: 600,
-              cursor: creating ? "default" : "pointer", opacity: creating ? 0.6 : 1, alignSelf: "flex-start",
-            }}
-          >
-            {creating ? t("common.loading") : t("groups.create")}
-          </button>
-        </form>
-      )}
-
-      {loading ? (
-        <p style={{ textAlign: "center", color: "#888", padding: 40 }}>{t("common.loading")}</p>
-      ) : groups.length === 0 ? (
-        <div style={{ textAlign: "center", padding: 40, color: "#888" }}>
-          <p style={{ fontSize: 16, marginBottom: 8 }}>{t("groups.noGroups")}</p>
-          <p style={{ fontSize: 14 }}>{t("groups.noGroupsHint")}</p>
-        </div>
-      ) : (
-        <div style={{ display: "flex", flexDirection: "column", gap: 12 }}>
-          {groups.map((group) => (
-            <div
-              key={group.id}
-              onClick={() => navigate(`/groups/${group.id}`)}
-              style={{
-                background: "#fff", padding: 20, borderRadius: 12, cursor: "pointer",
-                boxShadow: "0 2px 8px rgba(0,0,0,0.06)", transition: "box-shadow 0.2s",
-                display: "flex", justifyContent: "space-between", alignItems: "center",
-              }}
-              onMouseEnter={(e) => (e.currentTarget.style.boxShadow = "0 4px 16px rgba(0,0,0,0.1)")}
-              onMouseLeave={(e) => (e.currentTarget.style.boxShadow = "0 2px 8px rgba(0,0,0,0.06)")}
-            >
-              <div>
-                <h3 style={{ margin: 0, fontSize: 18, fontWeight: 600, color: "#1a1a2e" }}>{group.name}</h3>
-                {group.description && (
-                  <p style={{ margin: "6px 0 0", fontSize: 14, color: "#666" }}>{group.description}</p>
-                )}
-                <p style={{ margin: "8px 0 0", fontSize: 13, color: "#999" }}>
-                  {group.member_count} {t("groups.members")} · {t("groups.admin")}: {group.admin_email}
-                </p>
-              </div>
-              <span style={{ fontSize: 20, color: "#ccc" }}>→</span>
-            </div>
-          ))}
-        </div>
-      )}
-    </div>
-  );
-}

frontend/src/pages/Library.tsx

@@ -19,6 +19,7 @@ import { useVoiceSearch } from "../hooks/useVoiceSearch";
 import { useMediaQuery, BREAKPOINTS } from "../hooks/useMediaQuery";
 import { SearchSuggestions } from "../components/search/SearchSuggestions";
 import { BookContextMenu } from "../components/BookContextMenu";
+import { PaceNotification } from "../components/notifications/PaceNotification";
 
 interface FilterState {
   genre: string;
@@ -256,6 +257,9 @@ export function LibraryPage() {
         </div>
       </header>
 
+      {/* Pace Notifications */}
+      <PaceNotification />
+
       {/* Search Bar */}
       <div style={{ marginBottom: 16 }}>
         <div style={{ display: "flex", gap: 8, alignItems: "center" }}>

frontend/src/pages/Settings.tsx

@@ -2,7 +2,9 @@ import { useEffect, useState } from "react";
 import { useNavigate } from "react-router-dom";
 import { useTranslation } from "react-i18n-lite";
 import { booksApi } from "../api/books";
+import { groupsApi } from "../api/groups";
 import type { ReadingSettings } from "../types/book";
+import type { NotificationPreferences } from "../types/notifications";
 import type { SupportedLanguage } from "../locales";
 import { SimpleFormPageLayout } from "../components/layout/SimpleFormPageLayout";
 
@@ -17,6 +19,7 @@ export function SettingsPage() {
   const { t, language, setLanguage } = useTranslation();
   const navigate = useNavigate();
   const [settings, setSettings] = useState<ReadingSettings | null>(null);
+  const [notifPrefs, setNotifPrefs] = useState<NotificationPreferences | null>(null);
   const [loading, setLoading] = useState(true);
   const [saving, setSaving] = useState(false);
   const [error, setError] = useState<string | null>(null);
@@ -24,7 +27,14 @@ export function SettingsPage() {
 
   useEffect(() => {
     const load = async () => {
-      try { const data = await booksApi.getSettings(); setSettings(data); }
+      try {
+        const [data, notifData] = await Promise.all([
+          booksApi.getSettings(),
+          groupsApi.getPreferences(),
+        ]);
+        setSettings(data);
+        setNotifPrefs(notifData);
+      }
       catch (err) { setError(err instanceof Error ? err.message : t("settings.loadFailed")); }
       finally { setLoading(false); }
     };
@@ -32,9 +42,15 @@ export function SettingsPage() {
   }, [t]);
 
   const handleSave = async () => {
-    if (!settings) return;
+    if (!settings || !notifPrefs) return;
     setSaving(true); setError(null); setSuccess(false);
-    try { await booksApi.updateSettings(settings); setSuccess(true); setTimeout(() => setSuccess(false), 2000); }
+    try {
+      await Promise.all([
+        booksApi.updateSettings(settings),
+        groupsApi.updatePreferences(notifPrefs),
+      ]);
+      setSuccess(true); setTimeout(() => setSuccess(false), 2000);
+    }
     catch (err) { setError(err instanceof Error ? err.message : t("settings.saveFailed")); }
     finally { setSaving(false); }
   };
@@ -85,6 +101,48 @@ export function SettingsPage() {
           </div>
         </>}
 
+        {notifPrefs && <>
+          <div style={{ borderTop: "1px solid #e5e7eb", paddingTop: 20 }}>
+            <h3 style={{ fontSize: 16, fontWeight: 600, color: "#1f2937", marginBottom: 16 }}>
+              Notification Settings
+            </h3>
+
+            <div style={{ display: "flex", flexDirection: "column", gap: 12 }}>
+              <label style={{ display: "flex", alignItems: "center", gap: 10, fontSize: 14, color: "#374151", cursor: "pointer" }}>
+                <input
+                  type="checkbox"
+                  checked={notifPrefs.pace_notifications_enabled}
+                  onChange={(e) => setNotifPrefs({ ...notifPrefs, pace_notifications_enabled: e.target.checked })}
+                  style={{ width: 18, height: 18, cursor: "pointer" }}
+                />
+                Enable pace notifications
+              </label>
+
+              <label style={{ display: "flex", alignItems: "center", gap: 10, fontSize: 14, color: "#374151", cursor: "pointer" }}>
+                <input
+                  type="checkbox"
+                  checked={notifPrefs.reminder_enabled}
+                  onChange={(e) => setNotifPrefs({ ...notifPrefs, reminder_enabled: e.target.checked })}
+                  style={{ width: 18, height: 18, cursor: "pointer" }}
+                />
+                Enable pre-meeting reminders (24h before)
+              </label>
+
+              <div style={{ display: "flex", flexDirection: "column", gap: 8 }}>
+                <label style={{ fontSize: 14, fontWeight: 600, color: "#555" }}>Notification frequency</label>
+                <select
+                  value={notifPrefs.frequency}
+                  onChange={(e) => setNotifPrefs({ ...notifPrefs, frequency: e.target.value as NotificationPreferences["frequency"] })}
+                  style={{ padding: "10px 12px", borderRadius: 6, border: "1px solid #ddd", fontSize: 16, background: "#fff", outline: "none" }}
+                >
+                  <option value="daily">Daily</option>
+                  <option value="weekly">Weekly</option>
+                </select>
+              </div>
+            </div>
+          </div>
+        </>}
+
         <button onClick={handleSave} disabled={saving} style={{ padding: "12px 24px", borderRadius: 8, border: "none", background: "#1a1a2e", color: "#fff", fontSize: 16, fontWeight: 600, cursor: "pointer", opacity: saving ? 0.6 : 1, marginTop: 8 }}>{saving ? t("common.saving") : t("settings.saveSettings")}</button>
       </div>
     </SimpleFormPageLayout>

frontend/src/types/group.ts

@@ -1,109 +0,0 @@
-/** Types for reading groups, group books, sections, and schedules */
-
-export interface ReadingGroup {
-  id: number;
-  name: string;
-  description: string;
-  admin: number;
-  admin_email: string;
-  member_count: number;
-  created_at: string;
-  updated_at: string;
-}
-
-export interface ReadingGroupDetail {
-  id: number;
-  name: string;
-  description: string;
-  admin: number;
-  admin_email: string;
-  members: GroupMembership[];
-  created_at: string;
-  updated_at: string;
-}
-
-export interface GroupMembership {
-  id: number;
-  user: number;
-  user_email: string;
-  user_username: string;
-  role: "admin" | "member";
-  joined_at: string;
-}
-
-export interface GroupBook {
-  id: number;
-  title: string;
-  status: "active" | "replaced";
-  ebook: {
-    id: number;
-    title: string;
-    author: string;
-    filename: string;
-    format: string;
-    page_count: number;
-    file_size: number;
-    cover_image: string | null;
-    created_at: string;
-  };
-  uploaded_by: number;
-  uploaded_by_email: string;
-  section_count: number;
-  created_at: string;
-  updated_at: string;
-}
-
-export interface Section {
-  id: number;
-  title: string;
-  order: number;
-  start_chapter_index: number;
-  end_chapter_index: number;
-  estimated_reading_minutes: number;
-  created_at: string;
-}
-
-export interface GroupBookDetail extends GroupBook {
-  sections: Section[];
-  schedules: ReadingSchedule[];
-}
-
-export interface ReadingSchedule {
-  id: number;
-  meeting_number: number;
-  week_date: string;
-  section_ids: number[];
-  section_details: Section[];
-  created_at: string;
-}
-
-export interface MemberProgress {
-  id: number;
-  user: number;
-  user_email: string;
-  user_username: string;
-  current_section: number | null;
-  current_section_title: string | null;
-  completed_sections: number[];
-  updated_at: string;
-}
-
-export interface CreateGroupPayload {
-  name: string;
-  description?: string;
-}
-
-export interface AddMemberPayload {
-  user_id: number;
-}
-
-export interface CreateGroupBookPayload {
-  ebook_id: number;
-  title?: string;
-}
-
-export interface AdjustSectionsPayload {
-  operation: "merge" | "split";
-  section_ids: number[];
-  split_at?: number;
-}

frontend/src/types/notifications.ts

@@ -0,0 +1,65 @@
+export interface PaceStatus {
+  meeting_id: number;
+  meeting_title: string;
+  scheduled_at: string;
+  target_section: number;
+  target_section_label: string;
+  current_section: number;
+  ahead_behind_delta: number;
+  status: "ahead" | "behind" | "on_track" | "completed";
+  days_until_meeting: number;
+  sections_to_catch_up: number;
+  ebook_id: number;
+  ebook_title: string;
+}
+
+export interface NotificationPreferences {
+  pace_notifications_enabled: boolean;
+  reminder_enabled: boolean;
+  frequency: "daily" | "weekly";
+}
+
+export interface MeetingReminder {
+  meeting_id: number;
+  meeting_title: string;
+  scheduled_at: string;
+  target_section: number;
+  target_section_label: string;
+  group_name: string;
+  hours_until: number;
+  ebook_id: number;
+  ebook_title: string;
+}
+
+export interface ReadingGroup {
+  id: number;
+  name: string;
+  description: string;
+  book: number | null;
+  ebook: number | null;
+  created_by: number;
+  created_at: string;
+  member_count: number;
+  meeting_count: number;
+}
+
+export interface GroupMeeting {
+  id: number;
+  group: number;
+  group_name: string;
+  title: string;
+  scheduled_at: string;
+  target_section: number;
+  target_section_label: string;
+  created_at: string;
+}
+
+export interface GroupMembership {
+  id: number;
+  user: number;
+  user_email: string;
+  group: number;
+  group_name: string;
+  role: "admin" | "member";
+  joined_at: string;
+}

packages/shared/src/types.ts

@@ -216,47 +216,3 @@ export interface ApiError {
   detail?: string;
   [key: string]: unknown;
 }
-
-// ---- Reading Groups ----
-
-export interface ReadingGroup {
-  id: number;
-  name: string;
-  description: string;
-  admin: number;
-  admin_email: string;
-  member_count: number;
-  created_at: string;
-  updated_at: string;
-}
-
-export interface GroupMembership {
-  id: number;
-  user: number;
-  user_email: string;
-  user_username: string;
-  role: "admin" | "member";
-  joined_at: string;
-}
-
-export interface GroupBookSummary {
-  id: number;
-  title: string;
-  status: "active" | "replaced";
-  section_count: number;
-  created_at: string;
-}
-
-export interface SectionSummary {
-  id: number;
-  title: string;
-  order: number;
-  estimated_reading_minutes: number;
-}
-
-export interface ReadingScheduleEntry {
-  id: number;
-  meeting_number: number;
-  week_date: string;
-  section_ids: number[];
-}

packages/shared/src/utils.ts

@@ -114,14 +114,4 @@ export const API_ENDPOINTS = {
     bookmarkDetail: (id: string) => `/api/annotations/bookmarks/${id}/`,
     noteDetail: (id: string) => `/api/annotations/notes/${id}/`,
   },
-  groups: {
-    list: "/api/groups/",
-    detail: (id: number) => `/api/groups/${id}/`,
-    books: (groupId: number) => `/api/groups/${groupId}/books/`,
-    bookDetail: (groupId: number, bookId: number) => `/api/groups/${groupId}/books/${bookId}/`,
-    detectSections: (groupId: number, bookId: number) => `/api/groups/${groupId}/books/${bookId}/detect-sections/`,
-    adjustSections: (groupId: number, bookId: number) => `/api/groups/${groupId}/books/${bookId}/adjust-sections/`,
-    schedule: (groupId: number, bookId: number) => `/api/groups/${groupId}/books/${bookId}/schedule/`,
-    progress: (groupId: number, bookId: number) => `/api/groups/${groupId}/books/${bookId}/progress/`,
-  },
 } as const;