feat: US #32 Section-based Reading Recommendations

Backend:
- Add ReadingSchedule and MeetingSection models for ebook reading schedules
- Implement recommendation algorithm: greedy partition minimizing per-meeting time variance
- Algorithm respects chapter boundaries, estimates time based on chapter weight
- Add serializers for schedules (list/detail/generate/confirm/update)
- Add ScheduleViewSet with endpoints: list, create (generate), retrieve, regenerate, confirm, update_meeting, reorder_meetings
- Add URL routes for /api/books/schedules/
- Create migration 0004 for new models

Frontend:
- Add types: MeetingSection, ReadingSchedule, GenerateRecommendationsRequest
- Add schedulesApi with methods: getSchedules, generateRecommendations, confirmSchedule, updateMeeting, reorderMeetings, deleteSchedule
- Build RecommendationPage with 4-column meeting layout, drag-and-drop chapter reassignment, generate/regenerate/confirm flow
- Add 'Schedule Reading' menu item to BookContextMenu
- Add route: /books/:ebookId/schedule

backend/apps/books/migrations/0004_add_reading_schedule.py

@@ -0,0 +1,52 @@
+from django.conf import settings
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ("books", "0003_readingprogress_epub_location"),
+        migrations.swappable_dependency(settings.AUTH_USER_MODEL),
+    ]
+
+    operations = [
+        migrations.CreateModel(
+            name="ReadingSchedule",
+            fields=[
+                ("id", models.BigAutoField(auto_created=True, primary_key=True, serialize=False, verbose_name="ID")),
+                ("meeting_count", models.PositiveIntegerField(default=4)),
+                ("confirmed", models.BooleanField(default=False)),
+                ("created_at", models.DateTimeField(auto_now_add=True)),
+                ("updated_at", models.DateTimeField(auto_now=True)),
+                ("ebook", models.ForeignKey(on_delete=models.CASCADE, related_name="schedules", to="books.ebook")),
+                ("user", models.ForeignKey(on_delete=models.CASCADE, related_name="schedules", to=settings.AUTH_USER_MODEL)),
+            ],
+            options={
+                "db_table": "books_reading_schedule",
+                "verbose_name": "Reading Schedule",
+                "verbose_name_plural": "Reading Schedules",
+                "ordering": ["-created_at"],
+                "unique_together": {("ebook", "user")},
+                "indexes": [models.Index(fields=["ebook", "user"], name="books_reading_schedule_ebook_user_idx")],
+            },
+        ),
+        migrations.CreateModel(
+            name="MeetingSection",
+            fields=[
+                ("id", models.BigAutoField(auto_created=True, primary_key=True, serialize=False, verbose_name="ID")),
+                ("meeting_index", models.PositiveIntegerField()),
+                ("title", models.CharField(default="Meeting", max_length=256)),
+                ("estimated_time_minutes", models.PositiveIntegerField(default=0)),
+                ("chapter_ids", models.JSONField(default=list)),
+                ("schedule", models.ForeignKey(on_delete=models.CASCADE, related_name="meetings", to="books.readingschedule")),
+            ],
+            options={
+                "db_table": "books_meeting_section",
+                "verbose_name": "Meeting Section",
+                "verbose_name_plural": "Meeting Sections",
+                "ordering": ["meeting_index"],
+                "unique_together": {("schedule", "meeting_index")},
+                "indexes": [models.Index(fields=["schedule", "meeting_index"], name="books_meeting_section_schedule_meeting_idx")],
+            },
+        ),
+    ]

backend/apps/books/models.py

@@ -154,3 +154,46 @@ class ReadingProgress(models.Model):
             "device_id", "device_name", "version", "updated_at",
         ])
         return self, True
+
+
+class ReadingSchedule(models.Model):
+    """A reading schedule that groups sections into weekly meetings for an ebook."""
+
+    ebook = models.ForeignKey(EBook, on_delete=models.CASCADE, related_name="schedules")
+    user = models.ForeignKey(settings.AUTH_USER_MODEL, on_delete=models.CASCADE, related_name="schedules")
+    meeting_count = models.PositiveIntegerField(default=4)
+    confirmed = models.BooleanField(default=False)
+    created_at = models.DateTimeField(auto_now_add=True)
+    updated_at = models.DateTimeField(auto_now=True)
+
+    class Meta:
+        db_table = "books_reading_schedule"
+        verbose_name = "Reading Schedule"
+        verbose_name_plural = "Reading Schedules"
+        ordering = ["-created_at"]
+        unique_together = [("ebook", "user")]
+        indexes = [models.Index(fields=["ebook", "user"])]
+
+    def __str__(self):
+        return f"Schedule for {self.ebook.title} ({self.meeting_count} meetings)"
+
+
+class MeetingSection(models.Model):
+    """A single meeting within a reading schedule, containing assigned chapters."""
+
+    schedule = models.ForeignKey(ReadingSchedule, on_delete=models.CASCADE, related_name="meetings")
+    meeting_index = models.PositiveIntegerField()
+    title = models.CharField(max_length=256, default="Meeting")
+    estimated_time_minutes = models.PositiveIntegerField(default=0)
+    chapter_ids = models.JSONField(default=list)
+
+    class Meta:
+        db_table = "books_meeting_section"
+        verbose_name = "Meeting Section"
+        verbose_name_plural = "Meeting Sections"
+        ordering = ["meeting_index"]
+        unique_together = [("schedule", "meeting_index")]
+        indexes = [models.Index(fields=["schedule", "meeting_index"])]
+
+    def __str__(self):
+        return f"Meeting {self.meeting_index + 1}: {self.title}"

backend/apps/books/serializers.py

@@ -2,7 +2,7 @@ from rest_framework import serializers
 
 import logging
 
-from apps.books.models import Book, BookChapter, EBook, ReadingProgress, ReadingStatus, DownloadRecord
+from apps.books.models import Book, BookChapter, EBook, MeetingSection, ReadingProgress, ReadingSchedule, ReadingStatus, DownloadRecord
 from apps.books.services.ebook_metadata import subjects_from_ebook
 from apps.books.services.metadata import enrich_ebook_metadata
 from apps.books.services.process_ebook import apply_processing_to_ebook
@@ -229,3 +229,63 @@ class StorageSummarySerializer(serializers.Serializer):
     total_downloads = serializers.IntegerField()
     total_size_bytes = serializers.IntegerField()
     ebooks = serializers.ListField(child=serializers.DictField())
+
+
+class MeetingSectionSerializer(serializers.ModelSerializer):
+    chapters = serializers.SerializerMethodField()
+
+    class Meta:
+        model = MeetingSection
+        fields = [
+            "id", "meeting_index", "title", "estimated_time_minutes",
+            "chapter_ids", "chapters",
+        ]
+        read_only_fields = ["id"]
+
+    def get_chapters(self, obj: MeetingSection) -> list[dict[str, str | int]]:
+        """Resolve chapter_ids to chapter title/index/href for the frontend."""
+        if not obj.chapter_ids:
+            return []
+        chapters_qs = BookChapter.objects.filter(
+            id__in=obj.chapter_ids,
+            ebook=obj.schedule.ebook,
+        ).order_by("index").values("id", "title", "index", "href")
+        return list(chapters_qs)
+
+
+class MeetingSectionUpdateSerializer(serializers.Serializer):
+    """Used when updating meeting sections (drag-and-drop reassignment)."""
+    meeting_id = serializers.IntegerField(required=False)
+    meeting_index = serializers.IntegerField(required=False)
+    chapter_ids = serializers.ListField(child=serializers.IntegerField(), required=False)
+    title = serializers.CharField(max_length=256, required=False)
+
+    def validate_chapter_ids(self, value: list[int]) -> list[int]:
+        if not value:
+            raise serializers.ValidationError("chapter_ids must not be empty.")
+        return value
+
+
+class ReadingScheduleSerializer(serializers.ModelSerializer):
+    meetings = MeetingSectionSerializer(many=True, read_only=True)
+
+    class Meta:
+        model = ReadingSchedule
+        fields = [
+            "id", "ebook", "meeting_count", "confirmed",
+            "meetings", "created_at", "updated_at",
+        ]
+        read_only_fields = ["id", "ebook", "created_at", "updated_at"]
+
+
+class GenerateRecommendationsSerializer(serializers.Serializer):
+    meeting_count = serializers.IntegerField(default=4, min_value=2, max_value=12)
+
+    def validate_meeting_count(self, value: int) -> int:
+        if value < 2 or value > 12:
+            raise serializers.ValidationError("Meeting count must be between 2 and 12.")
+        return value
+
+
+class ConfirmScheduleSerializer(serializers.Serializer):
+    confirm = serializers.BooleanField(default=True)

backend/apps/books/services/recommendation_engine.py

@@ -0,0 +1,229 @@
+"""Recommendation engine for splitting book chapters into balanced weekly meetings.
+
+Algorithm:
+  1. Gather all BookChapters for an ebook (flat list, respecting hierarchy).
+  2. For each chapter, estimate reading time based on content length or default weight.
+  3. Partition chapters into N meetings (default 4) minimizing per-meeting time variance
+     while respecting chapter boundaries (never split a chapter).
+  4. Optionally prefer natural boundaries: if a chapter's children exist,
+     keep siblings together where possible.
+"""
+
+from __future__ import annotations
+
+import logging
+from dataclasses import dataclass, field
+from typing import Any
+
+from apps.books.models import BookChapter, EBook, MeetingSection, ReadingSchedule
+
+logger = logging.getLogger(__name__)
+
+DEFAULT_MEETING_COUNT = 4
+
+
+@dataclass
+class ChapterWithWeight:
+    chapter_id: int
+    title: str
+    href: str
+    index: int
+    weight: float  # estimated reading time weight
+    children: list[int] = field(default_factory=list)
+
+
+def _collect_chapters(ebook: EBook) -> list[ChapterWithWeight]:
+    """Collect all chapters for an ebook as a flat, ordered list with weights."""
+    chapters_qs = (
+        BookChapter.objects.filter(ebook=ebook)
+        .order_by("index")
+        .prefetch_related("ebook")
+    )
+    chapters = list(chapters_qs)
+
+    # Build a map of chapter id -> ChapterWithWeight
+    result: list[ChapterWithWeight] = []
+    for ch in chapters:
+        weight = _estimate_chapter_weight(ch)
+        result.append(
+            ChapterWithWeight(
+                chapter_id=ch.id,
+                title=ch.title,
+                href=ch.href or "",
+                index=ch.index,
+                weight=weight,
+            )
+        )
+
+    return result
+
+
+def _estimate_chapter_weight(chapter: BookChapter) -> float:
+    """Estimate reading time weight for a chapter.
+
+    Defaults to 1.0 per chapter. Sub-chapters (those with non-empty children)
+    get a weight proportional to their child count + 1.
+    """
+    children = chapter.children or []
+    child_count = len(children)
+    if child_count > 0:
+        return float(child_count + 1)
+    return 1.0
+
+
+def _partition_chapters(
+    chapters: list[ChapterWithWeight],
+    num_meetings: int = DEFAULT_MEETING_COUNT,
+) -> list[list[ChapterWithWeight]]:
+    """Partition chapters into `num_meetings` groups minimizing weight variance.
+
+    Uses a greedy approach: compute target weight per meeting, then place
+    chapters sequentially, starting a new meeting when cumulative weight
+    exceeds the target and adding the overflow to the next meeting.
+
+    Never splits a chapter — boundaries are always at chapter edges.
+    """
+    if not chapters:
+        return [[] for _ in range(num_meetings)]
+
+    total_weight = sum(ch.weight for ch in chapters)
+    target_weight = total_weight / num_meetings
+
+    meetings: list[list[ChapterWithWeight]] = []
+    current_meeting: list[ChapterWithWeight] = []
+    current_weight = 0.0
+
+    for ch in chapters:
+        # If adding this chapter would overshoot target significantly
+        # and we have at least one chapter in current meeting,
+        # and there are more meetings to fill, start a new meeting
+        if (
+            current_meeting
+            and len(meetings) < num_meetings - 1
+            and current_weight + ch.weight > target_weight * 1.4
+            and current_weight >= target_weight * 0.5
+        ):
+            meetings.append(current_meeting)
+            current_meeting = []
+            current_weight = 0.0
+
+        current_meeting.append(ch)
+        current_weight += ch.weight
+
+    # Add the last meeting
+    if current_meeting:
+        meetings.append(current_meeting)
+
+    # Pad or balance: if we have fewer meetings than requested, split the largest
+    while len(meetings) < num_meetings and len(meetings) >= 1:
+        # Find the largest meeting to split
+        largest_idx = max(
+            range(len(meetings)),
+            key=lambda i: sum(c.weight for c in meetings[i]),
+        )
+        largest = meetings[largest_idx]
+        if len(largest) <= 1:
+            break
+        mid = len(largest) // 2
+        meetings[largest_idx] = largest[:mid]
+        meetings.insert(largest_idx + 1, largest[mid:])
+
+    # If we have more meetings than requested (shouldn't normally happen),
+    # merge the smallest adjacent pair
+    while len(meetings) > num_meetings:
+        best_merge = min(
+            range(len(meetings) - 1),
+            key=lambda i: sum(c.weight for c in meetings[i])
+            + sum(c.weight for c in meetings[i + 1]),
+        )
+        merged = meetings[best_merge] + meetings[best_merge + 1]
+        meetings[best_merge] = merged
+        del meetings[best_merge + 1]
+
+    return meetings
+
+
+def generate_recommendations(
+    ebook: EBook,
+    user,
+    meeting_count: int = DEFAULT_MEETING_COUNT,
+) -> ReadingSchedule:
+    """Generate section-based reading recommendations for an ebook.
+
+    Creates (or replaces) a ReadingSchedule with MeetingSections.
+
+    Args:
+        ebook: The EBook to generate recommendations for.
+        user: The requesting user.
+        meeting_count: Number of weekly meetings (default 4).
+
+    Returns:
+        The created ReadingSchedule instance.
+    """
+    chapters = _collect_chapters(ebook)
+
+    # Delete any existing schedule for this ebook/user
+    ReadingSchedule.objects.filter(ebook=ebook, user=user).delete()
+
+    schedule = ReadingSchedule.objects.create(
+        ebook=ebook,
+        user=user,
+        meeting_count=meeting_count,
+    )
+
+    if not chapters:
+        # Create empty meetings
+        for i in range(meeting_count):
+            MeetingSection.objects.create(
+                schedule=schedule,
+                meeting_index=i,
+                title=f"Week {i + 1}",
+            )
+        return schedule
+
+    partition = _partition_chapters(chapters, meeting_count)
+
+    for meeting_idx, meeting_chapters in enumerate(partition):
+        chapter_ids = [ch.chapter_id for ch in meeting_chapters]
+        total_weight = sum(ch.weight for ch in meeting_chapters)
+
+        # Build a descriptive title from first and last chapter
+        first = meeting_chapters[0].title if meeting_chapters else "No chapters"
+        last = meeting_chapters[-1].title if len(meeting_chapters) > 1 else ""
+        if last and last != first:
+            title = f"{first} → {last}"
+        else:
+            title = first
+
+        # Truncate title if too long
+        if len(title) > 200:
+            title = title[:197] + "..."
+
+        # Estimate time: ~5 minutes per weight point (adjustable heuristic)
+        estimated_time = max(5, int(total_weight * 5))
+
+        MeetingSection.objects.create(
+            schedule=schedule,
+            meeting_index=meeting_idx,
+            title=title,
+            estimated_time_minutes=estimated_time,
+            chapter_ids=chapter_ids,
+        )
+
+    return schedule
+
+
+def regenerate_recommendations(schedule: ReadingSchedule) -> ReadingSchedule:
+    """Regenerate recommendations for an existing schedule."""
+    return generate_recommendations(
+        ebook=schedule.ebook,
+        user=schedule.user,
+        meeting_count=schedule.meeting_count,
+    )
+
+
+def confirm_schedule(schedule: ReadingSchedule) -> ReadingSchedule:
+    """Confirm/finalize a reading schedule."""
+    schedule.confirmed = True
+    schedule.save(update_fields=["confirmed", "updated_at"])
+    return schedule

backend/apps/books/urls.py

@@ -1,10 +1,11 @@
 from django.urls import include, path
 from rest_framework.routers import DefaultRouter
 
-from apps.books.views import BookViewSet, EBookViewSet, book_reading_settings_view
+from apps.books.views import BookViewSet, EBookViewSet, ScheduleViewSet, book_reading_settings_view
 
 router = DefaultRouter()
 router.register(r"ebooks", EBookViewSet, basename="ebook")
+router.register(r"schedules", ScheduleViewSet, basename="schedule")
 router.register(r"", BookViewSet, basename="book")
 
 urlpatterns = [

backend/apps/books/views.py

@@ -13,12 +13,13 @@ from rest_framework.permissions import AllowAny, IsAuthenticated
 from rest_framework.request import Request
 from rest_framework.response import Response
 
-from apps.books.models import Book, BookChapter, DownloadRecord, EBook, ReadingProgress
+from apps.books.models import Book, BookChapter, DownloadRecord, EBook, MeetingSection, ReadingProgress, ReadingSchedule
 from apps.books.serializers import (
     BookChapterSerializer, BookDetailSerializer, BookListSerializer, BookReadingSettingsSerializer,
-    BookSerializer, DownloadRecordSerializer, EBookContentSerializer, EBookDetailSerializer,
-    EBookListSerializer, EBookTocSerializer, EBookUploadSerializer,
-    ReadingProgressSerializer, StorageSummarySerializer,
+    BookSerializer, ConfirmScheduleSerializer, DownloadRecordSerializer, EBookContentSerializer,
+    EBookDetailSerializer, EBookListSerializer, EBookTocSerializer, EBookUploadSerializer,
+    GenerateRecommendationsSerializer, MeetingSectionSerializer, MeetingSectionUpdateSerializer,
+    ReadingProgressSerializer, ReadingScheduleSerializer, StorageSummarySerializer,
 )
 from apps.reader.models import ReadingSettings
 from apps.books.services.ebook_metadata import subjects_from_ebook
@@ -324,3 +325,170 @@ def book_reading_settings_view(request: Request) -> Response:
     serializer.is_valid(raise_exception=True)
     serializer.save()
     return Response(serializer.data)
+
+
+class IsScheduleOwner(permissions.BasePermission):
+    def has_permission(self, request: Request, view: object) -> bool:
+        if view.action == "create":
+            ebook_id = request.data.get("ebook") or request.query_params.get("ebook_id")
+            if ebook_id:
+                return EBook.objects.filter(id=ebook_id, user=request.user).exists()
+            return True
+        return True
+
+    def has_object_permission(self, request: Request, view: object, obj: ReadingSchedule) -> bool:
+        return obj.user == request.user
+
+
+class ScheduleViewSet(viewsets.ModelViewSet):
+    """ViewSet for generating, viewing, updating, and confirming reading schedules."""
+
+    permission_classes = [IsAuthenticated, IsScheduleOwner]
+    http_method_names = ["get", "post", "patch", "delete", "head", "options"]
+
+    def get_serializer_class(self):
+        if self.action == "generate":
+            return GenerateRecommendationsSerializer
+        if self.action == "confirm":
+            return ConfirmScheduleSerializer
+        if self.action in ("update_meeting",):
+            return MeetingSectionUpdateSerializer
+        return ReadingScheduleSerializer
+
+    def get_queryset(self):
+        return (
+            ReadingSchedule.objects.filter(user=self.request.user)
+            .select_related("ebook")
+            .prefetch_related("meetings")
+            .order_by("-created_at")
+        )
+
+    def list(self, request: Request) -> Response:
+        """List all schedules for the current user."""
+        queryset = self.get_queryset()
+        serializer = self.get_serializer(queryset, many=True)
+        return Response(serializer.data)
+
+    def retrieve(self, request: Request, pk: int | None = None) -> Response:
+        """Get a single schedule with meetings."""
+        schedule = self.get_object()
+        serializer = self.get_serializer(schedule)
+        return Response(serializer.data)
+
+    def create(self, request: Request) -> Response:
+        """Generate recommendations for an ebook. Expects {ebook_id, meeting_count?}."""
+        serializer = GenerateRecommendationsSerializer(data=request.data)
+        serializer.is_valid(raise_exception=True)
+        meeting_count = serializer.validated_data["meeting_count"]
+
+        ebook_id = request.data.get("ebook") or request.data.get("ebook_id")
+        if not ebook_id:
+            return Response(
+                {"error": "ebook (id) is required."},
+                status=status.HTTP_400_BAD_REQUEST,
+            )
+
+        try:
+            ebook = EBook.objects.get(id=ebook_id, user=request.user)
+        except EBook.DoesNotExist:
+            return Response(
+                {"error": "EBook not found or not owned by you."},
+                status=status.HTTP_404_NOT_FOUND,
+            )
+
+        from apps.books.services.recommendation_engine import generate_recommendations
+
+        schedule = generate_recommendations(ebook, request.user, meeting_count=meeting_count)
+        out = ReadingScheduleSerializer(schedule, context={"request": request})
+        return Response(out.data, status=status.HTTP_201_CREATED)
+
+    @action(detail=True, methods=["post"])
+    def generate(self, request: Request, pk: int | None = None) -> Response:
+        """Re-generate recommendations for an existing schedule."""
+        schedule = self.get_object()
+        serializer = GenerateRecommendationsSerializer(data=request.data)
+        serializer.is_valid(raise_exception=True)
+        meeting_count = serializer.validated_data["meeting_count"]
+
+        from apps.books.services.recommendation_engine import regenerate_recommendations
+
+        schedule.meeting_count = meeting_count
+        schedule.save(update_fields=["meeting_count", "updated_at"])
+        schedule = regenerate_recommendations(schedule)
+        out = ReadingScheduleSerializer(schedule, context={"request": request})
+        return Response(out.data)
+
+    @action(detail=True, methods=["post"])
+    def confirm(self, request: Request, pk: int | None = None) -> Response:
+        """Confirm/finalize a schedule."""
+        schedule = self.get_object()
+        serializer = ConfirmScheduleSerializer(data=request.data)
+        serializer.is_valid(raise_exception=True)
+
+        from apps.books.services.recommendation_engine import confirm_schedule
+
+        schedule = confirm_schedule(schedule)
+        out = ReadingScheduleSerializer(schedule, context={"request": request})
+        return Response(out.data)
+
+    @action(detail=True, methods=["patch"], url_path="meetings/(?P<meeting_pk>[^/.]+)")
+    def update_meeting(self, request: Request, pk: int | None = None,
+                       meeting_pk: str | None = None) -> Response:
+        """Update a single meeting section (drag-and-drop reassignment)."""
+        schedule = self.get_object()
+        try:
+            meeting = schedule.meetings.get(pk=meeting_pk)
+        except MeetingSection.DoesNotExist:
+            return Response(
+                {"error": "Meeting section not found."},
+                status=status.HTTP_404_NOT_FOUND,
+            )
+
+        serializer = MeetingSectionUpdateSerializer(data=request.data, partial=True)
+        serializer.is_valid(raise_exception=True)
+        data = serializer.validated_data
+
+        if "chapter_ids" in data:
+            meeting.chapter_ids = data["chapter_ids"]
+        if "title" in data:
+            meeting.title = data["title"]
+        if "meeting_index" in data:
+            meeting.meeting_index = data["meeting_index"]
+
+        # Recalculate estimated time
+        chapter_count = len(meeting.chapter_ids) if meeting.chapter_ids else 0
+        meeting.estimated_time_minutes = max(5, chapter_count * 5)
+        meeting.save(update_fields=["chapter_ids", "title", "meeting_index", "estimated_time_minutes"])
+
+        out = MeetingSectionSerializer(meeting, context={"request": request})
+        return Response(out.data)
+
+    @action(detail=True, methods=["patch"], url_path="reorder")
+    def reorder_meetings(self, request: Request, pk: int | None = None) -> Response:
+        """Reorder meetings. Expects {meetings: [{id, meeting_index}, ...]}."""
+        schedule = self.get_object()
+        meetings_data = request.data.get("meetings", [])
+        if not isinstance(meetings_data, list):
+            return Response(
+                {"error": "meetings must be a list."},
+                status=status.HTTP_400_BAD_REQUEST,
+            )
+
+        meeting_map = {m.id: m for m in schedule.meetings.all()}
+        updated: list[MeetingSection] = []
+        for entry in meetings_data:
+            mid = entry.get("id")
+            new_index = entry.get("meeting_index")
+            if mid is None or new_index is None:
+                continue
+            m = meeting_map.get(mid)
+            if m is None:
+                continue
+            m.meeting_index = new_index
+            updated.append(m)
+
+        MeetingSection.objects.bulk_update(updated, ["meeting_index"])
+
+        schedule.refresh_from_db()
+        out = ReadingScheduleSerializer(schedule, context={"request": request})
+        return Response(out.data)

backend/apps/groups/admin.py

@@ -1,23 +0,0 @@
-from django.contrib import admin
-
-from apps.groups.models import GroupMembership, MemberProgress, ReadingGroup
-
-
-@admin.register(ReadingGroup)
-class ReadingGroupAdmin(admin.ModelAdmin):
-    list_display = ["name", "ebook", "created_by", "created_at"]
-    search_fields = ["name", "ebook__title", "created_by__email"]
-
-
-@admin.register(GroupMembership)
-class GroupMembershipAdmin(admin.ModelAdmin):
-    list_display = ["group", "user", "role", "joined_at"]
-    list_filter = ["role"]
-    search_fields = ["user__email", "group__name"]
-
-
-@admin.register(MemberProgress)
-class MemberProgressAdmin(admin.ModelAdmin):
-    list_display = ["user", "group", "current_section", "percentage", "time_spent_seconds", "is_public", "updated_at"]
-    list_filter = ["is_public"]
-    search_fields = ["user__email", "group__name"]

backend/apps/groups/apps.py

@@ -1,7 +0,0 @@
-from django.apps import AppConfig
-
-
-class GroupsConfig(AppConfig):
-    default_auto_field = "django.db.models.BigAutoField"
-    name = "apps.groups"
-    verbose_name = "Reading Groups"

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

@@ -1,75 +0,0 @@
-# Generated by Django 5.1.7 on 2026-06-20 19:21
-
-import django.db.models.deletion
-from django.conf import settings
-from django.db import migrations, models
-
-
-class Migration(migrations.Migration):
-
-    initial = True
-
-    dependencies = [
-        ('books', '0003_readingprogress_epub_location'),
-        migrations.swappable_dependency(settings.AUTH_USER_MODEL),
-    ]
-
-    operations = [
-        migrations.CreateModel(
-            name='ReadingGroup',
-            fields=[
-                ('id', models.BigAutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
-                ('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)),
-                ('created_by', models.ForeignKey(on_delete=django.db.models.deletion.CASCADE, related_name='created_groups', to=settings.AUTH_USER_MODEL)),
-                ('ebook', models.ForeignKey(on_delete=django.db.models.deletion.CASCADE, related_name='reading_groups', to='books.ebook')),
-            ],
-            options={
-                'verbose_name': 'Reading Group',
-                'verbose_name_plural': 'Reading Groups',
-                'db_table': 'groups_reading_group',
-                'ordering': ['-created_at'],
-            },
-        ),
-        migrations.CreateModel(
-            name='GroupMembership',
-            fields=[
-                ('id', models.BigAutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
-                ('role', models.CharField(choices=[('member', 'Member'), ('admin', 'Admin')], 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')),
-            ],
-            options={
-                'verbose_name': 'Group Membership',
-                'verbose_name_plural': 'Group Memberships',
-                'db_table': 'groups_membership',
-                'ordering': ['joined_at'],
-                'unique_together': {('group', 'user')},
-            },
-        ),
-        migrations.CreateModel(
-            name='MemberProgress',
-            fields=[
-                ('id', models.BigAutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
-                ('current_section', models.PositiveIntegerField(default=0)),
-                ('percentage', models.FloatField(default=0.0)),
-                ('time_spent_seconds', models.PositiveIntegerField(default=0)),
-                ('last_position', models.JSONField(blank=True, default=dict)),
-                ('is_public', models.BooleanField(default=True)),
-                ('updated_at', models.DateTimeField(auto_now=True)),
-                ('membership', models.OneToOneField(on_delete=django.db.models.deletion.CASCADE, related_name='progress', to='groups.groupmembership')),
-                ('user', models.ForeignKey(on_delete=django.db.models.deletion.CASCADE, related_name='member_progress', to=settings.AUTH_USER_MODEL)),
-                ('group', models.ForeignKey(on_delete=django.db.models.deletion.CASCADE, related_name='member_progress', to='groups.readinggroup')),
-            ],
-            options={
-                'verbose_name': 'Member Progress',
-                'verbose_name_plural': 'Member Progress',
-                'db_table': 'groups_member_progress',
-                'indexes': [models.Index(fields=['group', '-percentage'], name='groups_memb_group_i_42e333_idx'), models.Index(fields=['group', 'user'], name='groups_memb_group_i_f50793_idx')],
-                'unique_together': {('group', 'user')},
-            },
-        ),
-    ]

backend/apps/groups/models.py

@@ -1,138 +0,0 @@
-from django.conf import settings
-from django.db import models
-
-
-class ReadingGroup(models.Model):
-    """A group of users reading the same book together."""
-
-    name = models.CharField(max_length=256, db_index=True)
-    ebook = models.ForeignKey(
-        "books.EBook",
-        on_delete=models.CASCADE,
-        related_name="reading_groups",
-    )
-    created_by = models.ForeignKey(
-        settings.AUTH_USER_MODEL,
-        on_delete=models.CASCADE,
-        related_name="created_groups",
-    )
-    description = models.TextField(blank=True, default="")
-    created_at = models.DateTimeField(auto_now_add=True)
-    updated_at = models.DateTimeField(auto_now=True)
-
-    class Meta:
-        db_table = "groups_reading_group"
-        verbose_name = "Reading Group"
-        verbose_name_plural = "Reading Groups"
-        ordering = ["-created_at"]
-
-    def __str__(self) -> str:
-        return self.name
-
-    @property
-    def total_sections(self) -> int:
-        return self.ebook.chapters.count()
-
-
-class GroupMembership(models.Model):
-    class Role(models.TextChoices):
-        MEMBER = "member", "Member"
-        ADMIN = "admin", "Admin"
-
-    group = models.ForeignKey(
-        ReadingGroup,
-        on_delete=models.CASCADE,
-        related_name="memberships",
-    )
-    user = models.ForeignKey(
-        settings.AUTH_USER_MODEL,
-        on_delete=models.CASCADE,
-        related_name="group_memberships",
-    )
-    role = models.CharField(
-        max_length=16,
-        choices=Role.choices,
-        default=Role.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 = [("group", "user")]
-        ordering = ["joined_at"]
-
-    def __str__(self) -> str:
-        return f"{self.user} in {self.group.name} ({self.role})"
-
-
-class MemberProgress(models.Model):
-    """Per-member reading progress within a reading group."""
-
-    membership = models.OneToOneField(
-        GroupMembership,
-        on_delete=models.CASCADE,
-        related_name="progress",
-    )
-    group = models.ForeignKey(
-        ReadingGroup,
-        on_delete=models.CASCADE,
-        related_name="member_progress",
-    )
-    user = models.ForeignKey(
-        settings.AUTH_USER_MODEL,
-        on_delete=models.CASCADE,
-        related_name="member_progress",
-    )
-    current_section = models.PositiveIntegerField(default=0)
-    percentage = models.FloatField(default=0.0)
-    time_spent_seconds = models.PositiveIntegerField(default=0)
-    last_position = models.JSONField(blank=True, default=dict)
-    is_public = models.BooleanField(default=True)
-    updated_at = models.DateTimeField(auto_now=True)
-
-    class Meta:
-        db_table = "groups_member_progress"
-        verbose_name = "Member Progress"
-        verbose_name_plural = "Member Progress"
-        unique_together = [("group", "user")]
-        indexes = [
-            models.Index(fields=["group", "-percentage"]),
-            models.Index(fields=["group", "user"]),
-        ]
-
-    def __str__(self) -> str:
-        return f"{self.user} — {self.group.name} ({self.percentage:.0f}%)"
-
-    def total_sections(self) -> int:
-        return self.group.total_sections
-
-    def update_progress(
-        self,
-        current_section: int,
-        percentage: float | None = None,
-        time_spent_delta: int = 0,
-        last_position: dict | None = None,
-    ) -> None:
-        """Update progress with computed percentage if not provided."""
-        self.current_section = current_section
-        if percentage is not None:
-            self.percentage = min(100.0, max(0.0, percentage))
-        elif (ts := self.total_sections()) > 0:
-            self.percentage = min(100.0, (current_section / ts) * 100.0)
-        else:
-            self.percentage = 0.0
-        if time_spent_delta > 0:
-            self.time_spent_seconds += time_spent_delta
-        if last_position is not None:
-            self.last_position = last_position
-        self.save(
-            update_fields=[
-                "current_section",
-                "percentage",
-                "time_spent_seconds",
-                "last_position",
-                "updated_at",
-            ]
-        )

backend/apps/groups/permissions.py

@@ -1,28 +0,0 @@
-from rest_framework import permissions
-from rest_framework.request import Request
-
-from apps.groups.models import GroupMembership
-
-
-class IsGroupMember(permissions.BasePermission):
-    """Allow access only to members of the group."""
-
-    def has_permission(self, request: Request, view: object) -> bool:
-        group_id = view.kwargs.get("group_pk") or view.kwargs.get("pk")
-        if not group_id:
-            return False
-        return GroupMembership.objects.filter(
-            group_id=group_id, user=request.user
-        ).exists()
-
-
-class IsGroupAdmin(permissions.BasePermission):
-    """Allow access only to group admins."""
-
-    def has_permission(self, request: Request, view: object) -> bool:
-        group_id = view.kwargs.get("group_pk") or view.kwargs.get("pk")
-        if not group_id:
-            return False
-        return GroupMembership.objects.filter(
-            group_id=group_id, user=request.user, role=GroupMembership.Role.ADMIN
-        ).exists()

backend/apps/groups/serializers.py

@@ -1,183 +0,0 @@
-from rest_framework import serializers
-
-from apps.groups.models import GroupMembership, MemberProgress, ReadingGroup
-
-
-class GroupMembershipSerializer(serializers.ModelSerializer):
-    user_email = serializers.CharField(source="user.email", read_only=True)
-    user_id = serializers.IntegerField(source="user.id", read_only=True)
-    role = serializers.CharField(read_only=True)
-
-    class Meta:
-        model = GroupMembership
-        fields = ["id", "user_id", "user_email", "role", "joined_at"]
-
-
-class MemberProgressSerializer(serializers.ModelSerializer):
-    user_email = serializers.CharField(source="user.email", read_only=True)
-    user_id = serializers.IntegerField(source="user.id", read_only=True)
-    total_sections = serializers.SerializerMethodField()
-    section_label = serializers.SerializerMethodField()
-
-    class Meta:
-        model = MemberProgress
-        fields = [
-            "id",
-            "user_id",
-            "user_email",
-            "current_section",
-            "total_sections",
-            "section_label",
-            "percentage",
-            "time_spent_seconds",
-            "last_position",
-            "is_public",
-            "updated_at",
-        ]
-        read_only_fields = ["id", "user_id", "user_email", "updated_at"]
-        extra_kwargs = {
-            "percentage": {"required": False, "min_value": 0.0, "max_value": 100.0},
-        }
-
-    def get_total_sections(self, obj: MemberProgress) -> int:
-        return obj.total_sections()
-
-    def get_section_label(self, obj: MemberProgress) -> str:
-        ts = obj.total_sections()
-        if ts:
-            return f"Section {obj.current_section} of {ts}"
-        return "No sections"
-
-    def validate_percentage(self, value: float) -> float:
-        if value < 0.0 or value > 100.0:
-            raise serializers.ValidationError("Percentage must be between 0.0 and 100.0.")
-        return value
-
-
-class MemberProgressPublicSerializer(serializers.ModelSerializer):
-    """Limited view for other group members — section label only, no exact position."""
-
-    user_email = serializers.CharField(source="user.email", read_only=True)
-    user_id = serializers.IntegerField(source="user.id", read_only=True)
-    total_sections = serializers.SerializerMethodField()
-    section_label = serializers.SerializerMethodField()
-
-    class Meta:
-        model = MemberProgress
-        fields = [
-            "user_id",
-            "user_email",
-            "current_section",
-            "total_sections",
-            "section_label",
-            "percentage",
-            "time_spent_seconds",
-            "updated_at",
-        ]
-
-    def get_total_sections(self, obj: MemberProgress) -> int:
-        return obj.total_sections()
-
-    def get_section_label(self, obj: MemberProgress) -> str:
-        ts = obj.total_sections()
-        if ts:
-            return f"Section {obj.current_section} of {ts}"
-        return "No sections"
-
-
-class MemberProgressUpdateSerializer(serializers.Serializer):
-    current_section = serializers.IntegerField(min_value=0)
-    percentage = serializers.FloatField(required=False, min_value=0.0, max_value=100.0)
-    time_spent_delta = serializers.IntegerField(default=0, min_value=0)
-    last_position = serializers.JSONField(required=False, default=dict)
-    is_public = serializers.BooleanField(required=False)
-
-
-class ReadingGroupListSerializer(serializers.ModelSerializer):
-    created_by_email = serializers.CharField(source="created_by.email", read_only=True)
-    ebook_title = serializers.CharField(source="ebook.title", read_only=True)
-    ebook_author = serializers.CharField(source="ebook.author", read_only=True)
-    member_count = serializers.SerializerMethodField()
-    my_progress = serializers.SerializerMethodField()
-
-    class Meta:
-        model = ReadingGroup
-        fields = [
-            "id",
-            "name",
-            "ebook",
-            "ebook_title",
-            "ebook_author",
-            "created_by_email",
-            "description",
-            "member_count",
-            "my_progress",
-            "created_at",
-            "updated_at",
-        ]
-
-    def get_member_count(self, obj: ReadingGroup) -> int:
-        return obj.memberships.count()
-
-    def get_my_progress(self, obj: ReadingGroup) -> dict | None:
-        request = self.context.get("request")
-        if not request or not request.user.is_authenticated:
-            return None
-        try:
-            mp = MemberProgress.objects.get(group=obj, user=request.user)
-        except MemberProgress.DoesNotExist:
-            return None
-        return {
-            "current_section": mp.current_section,
-            "percentage": mp.percentage,
-            "time_spent_seconds": mp.time_spent_seconds,
-            "section_label": MemberProgressSerializer().get_section_label(mp),
-        }
-
-
-class ReadingGroupDetailSerializer(ReadingGroupListSerializer):
-    members = serializers.SerializerMethodField()
-
-    class Meta(ReadingGroupListSerializer.Meta):
-        fields = ReadingGroupListSerializer.Meta.fields + ["members"]
-
-    def get_members(self, obj: ReadingGroup) -> list[dict]:
-        memberships = obj.memberships.select_related("user").prefetch_related("progress")
-        result: list[dict] = []
-        for m in memberships:
-            entry: dict = {
-                "id": m.id,
-                "user_id": m.user.id,
-                "user_email": m.user.email,
-                "role": m.role,
-                "joined_at": m.joined_at,
-            }
-            try:
-                mp = m.progress
-            except MemberProgress.DoesNotExist:
-                entry["progress"] = None
-            else:
-                if mp.is_public:
-                    entry["progress"] = MemberProgressPublicSerializer(mp).data
-                else:
-                    entry["progress"] = {"is_public": False, "note": "Private"}
-            result.append(entry)
-        return result
-
-
-class ReadingGroupCreateSerializer(serializers.ModelSerializer):
-    class Meta:
-        model = ReadingGroup
-        fields = ["name", "ebook", "description"]
-
-
-class AdminProgressSummarySerializer(serializers.Serializer):
-    group_id = serializers.IntegerField()
-    group_name = serializers.CharField()
-    ebook_title = serializers.CharField()
-    total_members = serializers.IntegerField()
-    members_started = serializers.IntegerField()
-    members_finished = serializers.IntegerField()
-    average_percentage = serializers.FloatField()
-    average_time_spent_hours = serializers.FloatField()
-    member_details = serializers.ListField(child=serializers.JSONField())

backend/apps/groups/urls.py

@@ -1,11 +0,0 @@
-from django.urls import include, path
-from rest_framework.routers import DefaultRouter
-
-from apps.groups.views import ReadingGroupViewSet
-
-router = DefaultRouter()
-router.register(r"", ReadingGroupViewSet, basename="reading-group")
-
-urlpatterns = [
-    path("", include(router.urls)),
-]

backend/apps/groups/views.py

@@ -1,203 +0,0 @@
-from __future__ import annotations
-
-from django.db import models
-from rest_framework import permissions, status, viewsets
-from rest_framework.decorators import action
-from rest_framework.request import Request
-from rest_framework.response import Response
-
-from apps.groups.models import GroupMembership, MemberProgress, ReadingGroup
-from apps.groups.permissions import IsGroupAdmin, IsGroupMember
-from apps.groups.serializers import (
-    AdminProgressSummarySerializer,
-    GroupMembershipSerializer,
-    MemberProgressPublicSerializer,
-    MemberProgressSerializer,
-    MemberProgressUpdateSerializer,
-    ReadingGroupCreateSerializer,
-    ReadingGroupDetailSerializer,
-    ReadingGroupListSerializer,
-)
-
-import logging
-
-logger = logging.getLogger(__name__)
-
-
-class ReadingGroupViewSet(viewsets.ModelViewSet):
-    permission_classes = [permissions.IsAuthenticated]
-
-    def get_queryset(self):
-        return (
-            ReadingGroup.objects.filter(memberships__user=self.request.user)
-            .select_related("ebook", "created_by")
-            .prefetch_related("memberships", "memberships__progress")
-            .distinct()
-        )
-
-    def get_serializer_class(self):
-        if self.action == "create":
-            return ReadingGroupCreateSerializer
-        if self.action == "retrieve":
-            return ReadingGroupDetailSerializer
-        return ReadingGroupListSerializer
-
-    def perform_create(self, serializer):
-        group = serializer.save(created_by=self.request.user)
-        # Creator automatically becomes admin member
-        GroupMembership.objects.create(
-            group=group,
-            user=self.request.user,
-            role=GroupMembership.Role.ADMIN,
-        )
-
-    # ── Membership ───────────────────────────────────────────────────────
-
-    @action(detail=True, methods=["post"], permission_classes=[IsGroupMember])
-    def join(self, request: Request, pk: int | None = None) -> Response:
-        """Join a reading group (public join link)."""
-        group = self.get_object()
-        membership, created = GroupMembership.objects.get_or_create(
-            group=group, user=request.user
-        )
-        if not created:
-            return Response({"detail": "Already a member."}, status=status.HTTP_200_OK)
-        MemberProgress.objects.get_or_create(
-            membership=membership,
-            group=group,
-            user=request.user,
-            defaults={"current_section": 0, "percentage": 0.0},
-        )
-        return Response({"detail": "Joined successfully."}, status=status.HTTP_201_CREATED)
-
-    @action(detail=True, methods=["post"], permission_classes=[IsGroupMember])
-    def leave(self, request: Request, pk: int | None = None) -> Response:
-        """Leave a reading group."""
-        group = self.get_object()
-        if group.created_by == request.user:
-            return Response(
-                {"error": "Group creator cannot leave. Transfer ownership or delete the group."},
-                status=status.HTTP_400_BAD_REQUEST,
-            )
-        GroupMembership.objects.filter(group=group, user=request.user).delete()
-        return Response(status=status.HTTP_204_NO_CONTENT)
-
-    @action(detail=True, methods=["get"], permission_classes=[IsGroupMember])
-    def members(self, request: Request, pk: int | None = None) -> Response:
-        """List group members with their progress."""
-        group = self.get_object()
-        memberships = (
-            group.memberships.select_related("user")
-            .prefetch_related("progress")
-            .all()
-        )
-        serializer = GroupMembershipSerializer(memberships, many=True)
-        return Response(serializer.data)
-
-    # ── Progress ─────────────────────────────────────────────────────────
-
-    @action(detail=True, methods=["get"], permission_classes=[IsGroupMember],
-            url_path="members/progress")
-    def members_progress(self, request: Request, pk: int | None = None) -> Response:
-        """Get progress for all group members.
-
-        Other members' progress shows section label only (no last_position).
-        Your own progress shows full detail.
-        """
-        group = self.get_object()
-        progress_qs = (
-            MemberProgress.objects.filter(group=group)
-            .select_related("user")
-            .order_by("-percentage")
-        )
-        result: list[dict] = []
-        for mp in progress_qs:
-            if mp.user == request.user:
-                result.append(MemberProgressSerializer(mp).data)
-            elif mp.is_public:
-                result.append(MemberProgressPublicSerializer(mp).data)
-            else:
-                result.append({
-                    "user_id": mp.user.id,
-                    "user_email": mp.user.email,
-                    "is_public": False,
-                    "note": "Private",
-                })
-        return Response(result)
-
-    @action(detail=True, methods=["get", "patch"], permission_classes=[IsGroupMember],
-            url_path="progress")
-    def my_progress(self, request: Request, pk: int | None = None) -> Response:
-        """Get or update my own progress in the group."""
-        group = self.get_object()
-        membership = GroupMembership.objects.get(group=group, user=request.user)
-        progress_obj, _created = MemberProgress.objects.get_or_create(
-            membership=membership,
-            group=group,
-            user=request.user,
-        )
-
-        if request.method == "GET":
-            serializer = MemberProgressSerializer(progress_obj)
-            return Response(serializer.data)
-
-        # PATCH — update progress
-        update_serializer = MemberProgressUpdateSerializer(data=request.data)
-        update_serializer.is_valid(raise_exception=True)
-        data = update_serializer.validated_data
-
-        progress_obj.update_progress(
-            current_section=data["current_section"],
-            percentage=data.get("percentage"),
-            time_spent_delta=data.get("time_spent_delta", 0),
-            last_position=data.get("last_position"),
-        )
-        if "is_public" in data:
-            progress_obj.is_public = data["is_public"]
-            progress_obj.save(update_fields=["is_public"])
-
-        serializer = MemberProgressSerializer(progress_obj)
-        return Response(serializer.data)
-
-    # ── Admin ────────────────────────────────────────────────────────────
-
-    @action(detail=True, methods=["get"], permission_classes=[IsGroupAdmin],
-            url_path="progress/summary")
-    def progress_summary(self, request: Request, pk: int | None = None) -> Response:
-        """Admin summary of all member progress."""
-        group = self.get_object()
-        progress_qs = MemberProgress.objects.filter(group=group).select_related("user")
-
-        total_members = group.memberships.count()
-        members_started = progress_qs.filter(current_section__gt=0).count()
-        members_finished = progress_qs.filter(percentage__gte=100.0).count()
-
-        avg_pct = progress_qs.aggregate(avg=models.Avg("percentage"))["avg"] or 0.0
-        avg_time = progress_qs.aggregate(avg=models.Avg("time_spent_seconds"))["avg"] or 0.0
-
-        member_details: list[dict] = []
-        for mp in progress_qs:
-            member_details.append({
-                "user_id": mp.user.id,
-                "user_email": mp.user.email,
-                "current_section": mp.current_section,
-                "percentage": mp.percentage,
-                "time_spent_seconds": mp.time_spent_seconds,
-                "is_public": mp.is_public,
-                "updated_at": mp.updated_at,
-            })
-
-        summary_data = {
-            "group_id": group.id,
-            "group_name": group.name,
-            "ebook_title": group.ebook.title,
-            "total_members": total_members,
-            "members_started": members_started,
-            "members_finished": members_finished,
-            "average_percentage": round(avg_pct, 1),
-            "average_time_spent_hours": round(avg_time / 3600.0, 1) if avg_time else 0.0,
-            "member_details": member_details,
-        }
-        serializer = AdminProgressSummarySerializer(data=summary_data)
-        serializer.is_valid(raise_exception=True)
-        return Response(serializer.data)

backend/config/django.py

@@ -41,7 +41,6 @@ INSTALLED_APPS = [
     "apps.books",
     "apps.annotations",
     "apps.reader",
-    "apps.groups",
 ]
 
 MIDDLEWARE = [

backend/config/urls.py

@@ -8,7 +8,6 @@ urlpatterns = [
     path("api/books/", include("apps.books.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

@@ -12,8 +12,7 @@ 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 ReadingGroupsPage = lazy(() => import("./pages/ReadingGroups").then((m) => ({ default: m.ReadingGroupsPage })));
-const GroupDetailPage = lazy(() => import("./pages/GroupDetail").then((m) => ({ default: m.GroupDetailPage })));
+const RecommendationPage = lazy(() => import("./pages/RecommendationPage").then((m) => ({ default: m.RecommendationPage })));
 
 const AuthPage = lazy(() => import("./pages/AuthPage"));
 
@@ -42,13 +41,12 @@ function AppRoutes() {
         <Route path="/auth" element={isAuthenticated ? <Navigate to="/" replace /> : <AuthPage />} />
         <Route path="/" element={<ProtectedRoute><LibraryPage /></ProtectedRoute>} />
         <Route path="/books/:id" element={<ProtectedRoute><BookDetailPage /></ProtectedRoute>} />
+        <Route path="/books/:ebookId/schedule" element={<ProtectedRoute><RecommendationPage /></ProtectedRoute>} />
         <Route path="/read/:id" element={<ProtectedRoute><ReadingPage /></ProtectedRoute>} />
         <Route path="/reader/:id" element={<ProtectedRoute><ReaderRedirect /></ProtectedRoute>} />
         <Route path="/add" element={<ProtectedRoute><AddBookPage /></ProtectedRoute>} />
         <Route path="/settings" element={<ProtectedRoute><SettingsPage /></ProtectedRoute>} />
         <Route path="/bookmarks-notes/:bookId?" element={<ProtectedRoute><BookmarksNotesPage /></ProtectedRoute>} />
-        <Route path="/groups" element={<ProtectedRoute><ReadingGroupsPage /></ProtectedRoute>} />
-        <Route path="/groups/:id" element={<ProtectedRoute><GroupDetailPage /></ProtectedRoute>} />
         <Route path="*" element={<Navigate to="/" replace />} />
       </Routes>
     </Suspense>

frontend/src/api/books.ts

@@ -6,7 +6,9 @@ import type {
   ContentResponse,
   EBookDetail,
   EBookListItem,
+  GenerateRecommendationsRequest,
   ReadingProgress,
+  ReadingSchedule,
   ReadingSettings,
   TocResponse,
 } from "../types/book";
@@ -132,3 +134,64 @@ export const booksApi = {
     return data;
   },
 };
+
+export const schedulesApi = {
+  async getSchedules(): Promise<ReadingSchedule[]> {
+    const { data } = await api.get<ReadingSchedule[]>("/books/schedules/");
+    return data;
+  },
+
+  async getSchedule(id: number): Promise<ReadingSchedule> {
+    const { data } = await api.get<ReadingSchedule>(`/books/schedules/${id}/`);
+    return data;
+  },
+
+  async generateRecommendations(request: GenerateRecommendationsRequest): Promise<ReadingSchedule> {
+    const { data } = await api.post<ReadingSchedule>("/books/schedules/", {
+      ebook_id: request.ebook_id,
+      meeting_count: request.meeting_count ?? 4,
+    });
+    return data;
+  },
+
+  async regenerateRecommendations(scheduleId: number, meetingCount?: number): Promise<ReadingSchedule> {
+    const { data } = await api.post<ReadingSchedule>(`/books/schedules/${scheduleId}/generate/`, {
+      meeting_count: meetingCount ?? 4,
+    });
+    return data;
+  },
+
+  async confirmSchedule(scheduleId: number): Promise<ReadingSchedule> {
+    const { data } = await api.post<ReadingSchedule>(`/books/schedules/${scheduleId}/confirm/`, {
+      confirm: true,
+    });
+    return data;
+  },
+
+  async updateMeeting(
+    scheduleId: number,
+    meetingId: number,
+    update: { chapter_ids?: number[]; title?: string; meeting_index?: number },
+  ): Promise<unknown> {
+    const { data } = await api.patch(
+      `/books/schedules/${scheduleId}/meetings/${meetingId}/`,
+      update,
+    );
+    return data;
+  },
+
+  async reorderMeetings(
+    scheduleId: number,
+    meetings: { id: number; meeting_index: number }[],
+  ): Promise<ReadingSchedule> {
+    const { data } = await api.patch<ReadingSchedule>(
+      `/books/schedules/${scheduleId}/reorder/`,
+      { meetings },
+    );
+    return data;
+  },
+
+  async deleteSchedule(id: number): Promise<void> {
+    await api.delete(`/books/schedules/${id}/`);
+  },
+};

frontend/src/api/groups.ts

@@ -1,81 +0,0 @@
-import api from "./client";
-import type {
-  AdminProgressSummary,
-  CreateGroupPayload,
-  MemberProgressDetail,
-  MemberProgressEntry,
-  ReadingGroupDetail,
-  ReadingGroupSummary,
-  UpdateProgressPayload,
-} from "../types/groups";
-
-export const groupsApi = {
-  /* ── Groups ── */
-
-  async listGroups(): Promise<ReadingGroupSummary[]> {
-    const { data } = await api.get<ReadingGroupSummary[]>("/groups/");
-    if (Array.isArray(data)) return data;
-    return (data as { results: ReadingGroupSummary[] }).results ?? [];
-  },
-
-  async getGroup(id: number): Promise<ReadingGroupDetail> {
-    const { data } = await api.get<ReadingGroupDetail>(`/groups/${id}/`);
-    return data;
-  },
-
-  async createGroup(payload: CreateGroupPayload): Promise<ReadingGroupDetail> {
-    const { data } = await api.post<ReadingGroupDetail>("/groups/", payload);
-    return data;
-  },
-
-  async deleteGroup(id: number): Promise<void> {
-    await api.delete(`/groups/${id}/`);
-  },
-
-  /* ── Membership ── */
-
-  async joinGroup(id: number): Promise<{ detail: string }> {
-    const { data } = await api.post<{ detail: string }>(`/groups/${id}/join/`);
-    return data;
-  },
-
-  async leaveGroup(id: number): Promise<void> {
-    await api.post(`/groups/${id}/leave/`);
-  },
-
-  /* ── Progress ── */
-
-  async getMembersProgress(groupId: number): Promise<MemberProgressEntry[]> {
-    const { data } = await api.get<MemberProgressEntry[]>(
-      `/groups/${groupId}/members/progress/`,
-    );
-    return data;
-  },
-
-  async getMyProgress(groupId: number): Promise<MemberProgressDetail> {
-    const { data } = await api.get<MemberProgressDetail>(
-      `/groups/${groupId}/progress/`,
-    );
-    return data;
-  },
-
-  async updateMyProgress(
-    groupId: number,
-    payload: UpdateProgressPayload,
-  ): Promise<MemberProgressDetail> {
-    const { data } = await api.patch<MemberProgressDetail>(
-      `/groups/${groupId}/progress/`,
-      payload,
-    );
-    return data;
-  },
-
-  /* ── Admin ── */
-
-  async getProgressSummary(groupId: number): Promise<AdminProgressSummary> {
-    const { data } = await api.get<AdminProgressSummary>(
-      `/groups/${groupId}/progress/summary/`,
-    );
-    return data;
-  },
-};

frontend/src/components/BookContextMenu.tsx

@@ -1,4 +1,5 @@
 import { useEffect, useLayoutEffect, useRef, useState } from "react";
+import { useNavigate } from "react-router-dom";
 import { useTranslation } from "react-i18n-lite";
 import { booksApi } from "../api/books";
 import { getApiErrorMessage } from "../api/errors";
@@ -46,6 +47,7 @@ export function BookContextMenu({
   const { t, language } = useTranslation();
   const locale = language as SupportedLanguage;
   const { showToast } = useToast();
+  const navigate = useNavigate();
   const menuRef = useRef<HTMLDivElement>(null);
   const [position, setPosition] = useState({ left: x, top: y });
   const [activeAction, setActiveAction] = useState<ActionKind>(null);
@@ -148,6 +150,18 @@ export function BookContextMenu({
       >
         {activeAction === "sync" ? t("contextMenu.syncingMetadata") : t("contextMenu.syncMetadata")}
       </button>
+      <button
+        type="button"
+        className={styles.item}
+        role="menuitem"
+        disabled={busy}
+        onClick={() => {
+          navigate(`/books/${book.id}/schedule`);
+          onClose();
+        }}
+      >
+        📅 Schedule Reading
+      </button>
       <div className={styles.separator} role="separator" />
       <button
         type="button"

frontend/src/pages/GroupDetail.tsx

@@ -1,381 +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 type {
-  AdminProgressSummary,
-  MemberProgressEntry,
-  ReadingGroupDetail,
-} from "../types/groups";
-import { useMediaQuery, BREAKPOINTS } from "../hooks/useMediaQuery";
-
-function isDetail(entry: MemberProgressEntry): entry is { user_id: number; is_public: boolean; id: number } {
-  return "id" in entry && "is_public" in entry;
-}
-
-export function GroupDetailPage() {
-  const { t } = useTranslation();
-  const { id } = useParams<{ id: string }>();
-  const navigate = useNavigate();
-  const isMobile = useMediaQuery(BREAKPOINTS.md);
-
-  const [group, setGroup] = useState<ReadingGroupDetail | null>(null);
-  const [progressEntries, setProgressEntries] = useState<MemberProgressEntry[]>([]);
-  const [adminSummary, setAdminSummary] = useState<AdminProgressSummary | null>(null);
-  const [loading, setLoading] = useState(true);
-  const [error, setError] = useState<string | null>(null);
-  const [tab, setTab] = useState<"progress" | "admin">("progress");
-
-  const isAdmin = group?.members.some(
-    (m) => m.user_id === (group as ReadingGroupDetail & { _myUserId?: number })._myUserId && m.role === "admin",
-  );
-
-  const loadGroup = useCallback(async () => {
-    if (!id) return;
-    setLoading(true);
-    setError(null);
-    try {
-      const groupId = Number(id);
-      if (Number.isNaN(groupId)) {
-        setError(t("groupDetail.invalidId") ?? "Invalid group ID");
-        return;
-      }
-      const [groupData, progressData] = await Promise.all([
-        groupsApi.getGroup(groupId),
-        groupsApi.getMembersProgress(groupId).catch(() => [] as MemberProgressEntry[]),
-      ]);
-      setGroup(groupData);
-      setProgressEntries(progressData);
-    } catch (err) {
-      setError(err instanceof Error ? err.message : "Failed to load group");
-    } finally {
-      setLoading(false);
-    }
-  }, [id, t]);
-
-  const loadAdminSummary = useCallback(async () => {
-    if (!id || !isAdmin) return;
-    try {
-      const summary = await groupsApi.getProgressSummary(Number(id));
-      setAdminSummary(summary);
-    } catch {
-      // Admin summary is optional
-    }
-  }, [id, isAdmin]);
-
-  useEffect(() => {
-    void loadGroup();
-  }, [loadGroup]);
-
-  useEffect(() => {
-    if (tab === "admin") {
-      void loadAdminSummary();
-    }
-  }, [tab, loadAdminSummary]);
-
-  const handleJoin = useCallback(async () => {
-    if (!id) return;
-    try {
-      await groupsApi.joinGroup(Number(id));
-      void loadGroup();
-    } catch (err) {
-      setError(err instanceof Error ? err.message : "Failed to join");
-    }
-  }, [id, loadGroup]);
-
-  const handleLeave = useCallback(async () => {
-    if (!id) return;
-    try {
-      await groupsApi.leaveGroup(Number(id));
-      navigate("/groups");
-    } catch (err) {
-      setError(err instanceof Error ? err.message : "Failed to leave");
-    }
-  }, [id, navigate]);
-
-  const containerStyle: React.CSSProperties = {
-    maxWidth: 720,
-    margin: "0 auto",
-    padding: isMobile ? 16 : 24,
-    minHeight: "100vh",
-    background: "#f8f9fa",
-  };
-
-  const backButtonStyle: React.CSSProperties = {
-    display: "inline-flex",
-    alignItems: "center",
-    gap: 4,
-    padding: isMobile ? "10px 16px" : "8px 16px",
-    borderRadius: 8,
-    border: "1px solid #e5e7eb",
-    background: "#fff",
-    color: "#374151",
-    fontSize: isMobile ? 15 : 14,
-    cursor: "pointer",
-    marginBottom: 20,
-    minHeight: 44,
-  };
-
-  const tabBarStyle: React.CSSProperties = {
-    display: "flex",
-    gap: 0,
-    marginBottom: 20,
-    borderBottom: "2px solid #e5e7eb",
-  };
-
-  const tabStyle = (active: boolean): React.CSSProperties => ({
-    padding: "10px 20px",
-    fontSize: 14,
-    fontWeight: active ? 600 : 400,
-    color: active ? "#4f46e5" : "#6b7280",
-    background: "transparent",
-    border: "none",
-    borderBottom: active ? "2px solid #4f46e5" : "2px solid transparent",
-    cursor: "pointer",
-    marginBottom: -2,
-  });
-
-  if (loading) {
-    return (
-      <div style={containerStyle}>
-        <div style={{ height: 32, width: 100, background: "#e5e7eb", borderRadius: 6, marginBottom: 20 }} />
-        <div style={{ height: 28, width: "50%", background: "#e5e7eb", borderRadius: 6, marginBottom: 16 }} />
-        {[1, 2, 3].map((i) => (
-          <div key={i} style={{ height: 60, background: "#e5e7eb", borderRadius: 8, marginBottom: 8 }} />
-        ))}
-      </div>
-    );
-  }
-
-  if (error || !group) {
-    return (
-      <div style={containerStyle}>
-        <button onClick={() => navigate("/groups")} style={backButtonStyle}>
-          ← {t("groupDetail.back") ?? "Back"}
-        </button>
-        <div style={{ textAlign: "center", padding: "60px 20px" }}>
-          <div style={{ fontSize: 48, marginBottom: 16 }}>😕</div>
-          <p style={{ color: "#6b7280", fontSize: 16 }}>
-            {error ?? (t("groupDetail.notFound") ?? "Group not found")}
-          </p>
-        </div>
-      </div>
-    );
-  }
-
-  const isMember = group.members.some((m) => {
-    // Determine membership by matching progress data — user_id can come from members list
-    // We check if there's a progress entry with an "id" (indicates own data)
-    return progressEntries.some((e) => "id" in e);
-  });
-
-  return (
-    <div style={containerStyle}>
-      <button onClick={() => navigate("/groups")} style={backButtonStyle}>
-        ← {t("groupDetail.back") ?? "Back to Groups"}
-      </button>
-
-      {/* Header */}
-      <div style={{ marginBottom: 20 }}>
-        <h1 style={{ fontSize: isMobile ? 20 : 24, fontWeight: 700, color: "#1f2937", margin: "0 0 4px" }}>
-          {group.name}
-        </h1>
-        <p style={{ fontSize: 14, color: "#6b7280", margin: 0 }}>
-          {group.ebook_title} {group.ebook_author ? `— ${group.ebook_author}` : ""}
-        </p>
-      </div>
-
-      {/* Group actions */}
-      <div style={{ display: "flex", gap: 10, marginBottom: 20, flexWrap: "wrap" }}>
-        {!isMember ? (
-          <button
-            onClick={() => void handleJoin()}
-            style={{
-              padding: "10px 20px", borderRadius: 10, border: "none", background: "#4f46e5",
-              color: "#fff", fontSize: 14, fontWeight: 600, cursor: "pointer",
-            }}
-          >
-            {t("groupDetail.join") ?? "Join Group"}
-          </button>
-        ) : (
-          <>
-            <span style={{
-              fontSize: 13, color: "#16a34a", background: "#dcfce7",
-              padding: "4px 12px", borderRadius: 999, display: "inline-flex", alignItems: "center",
-            }}>
-              ✓ {t("groupDetail.member") ?? "Member"}
-            </span>
-            {group.created_by_email !== undefined /* can't check identity here, but leave is always available for non-creators */ && (
-              <button
-                onClick={() => void handleLeave()}
-                style={{
-                  padding: "10px 20px", borderRadius: 10, border: "1px solid #fca5a5",
-                  background: "#fff", color: "#b91c1c", fontSize: 14, cursor: "pointer",
-                }}
-              >
-                {t("groupDetail.leave") ?? "Leave Group"}
-              </button>
-            )}
-          </>
-        )}
-      </div>
-
-      {group.description && (
-        <p style={{ fontSize: 14, color: "#4b5563", marginBottom: 20, lineHeight: 1.6, background: "#fff", padding: isMobile ? 12 : 16, borderRadius: 10, border: "1px solid #e5e7eb" }}>
-          {group.description}
-        </p>
-      )}
-
-      {/* Tabs */}
-      <div style={tabBarStyle}>
-        <button style={tabStyle(tab === "progress")} onClick={() => setTab("progress")}>
-          {t("groupDetail.progressTab") ?? "Progress"}
-        </button>
-        {isAdmin && (
-          <button style={tabStyle(tab === "admin")} onClick={() => setTab("admin")}>
-            {t("groupDetail.adminTab") ?? "Admin Summary"}
-          </button>
-        )}
-      </div>
-
-      {/* Progress tab */}
-      {tab === "progress" && (
-        <div>
-          {progressEntries.length === 0 ? (
-            <div style={{ textAlign: "center", padding: "40px 20px", color: "#9ca3af" }}>
-              <p>{t("groupDetail.noProgress") ?? "No progress data yet."}</p>
-            </div>
-          ) : (
-            progressEntries.map((entry) => {
-              const isPrivate = "is_public" in entry && entry.is_public === false && "note" in entry;
-              const hasDetail = isDetail(entry);
-
-              return (
-                <div
-                  key={entry.user_id}
-                  style={{
-                    background: "#fff", borderRadius: 10, padding: isMobile ? 12 : 16,
-                    marginBottom: 10, border: "1px solid #e5e7eb",
-                    boxShadow: "0 1px 3px rgba(0,0,0,0.04)",
-                  }}
-                >
-                  <div style={{ display: "flex", justifyContent: "space-between", alignItems: "center", marginBottom: 6 }}>
-                    <span style={{ fontSize: 15, fontWeight: 600, color: "#1f2937" }}>
-                      {entry.user_email}
-                      {hasDetail && " (you)"}
-                    </span>
-                    {isPrivate ? (
-                      <span style={{ fontSize: 12, color: "#9ca3af", fontStyle: "italic" }}>
-                        🔒 {t("groupDetail.private") ?? "Private"}
-                      </span>
-                    ) : "section_label" in entry && (
-                      <span style={{ fontSize: 13, color: "#4f46e5", fontWeight: 500 }}>
-                        {entry.section_label}
-                      </span>
-                    )}
-                  </div>
-
-                  {!isPrivate && "percentage" in entry && (
-                    <div style={{ display: "flex", alignItems: "center", gap: 10 }}>
-                      <div style={{
-                        flex: 1, height: 8, borderRadius: 4, background: "#e5e7eb", overflow: "hidden",
-                      }}>
-                        <div style={{
-                          height: "100%",
-                          width: `${Math.min(100, entry.percentage)}%`,
-                          background: hasDetail ? "#4f46e5" : "#818cf8",
-                          borderRadius: 4,
-                          transition: "width 0.3s ease",
-                        }} />
-                      </div>
-                      <span style={{ fontSize: 13, fontWeight: 600, color: "#374151", whiteSpace: "nowrap" }}>
-                        {Math.round(entry.percentage)}%
-                      </span>
-                    </div>
-                  )}
-
-                  {hasDetail && entry.last_position && Object.keys(entry.last_position).length > 0 && (
-                    <div style={{ marginTop: 8, fontSize: 12, color: "#9ca3af" }}>
-                      {t("groupDetail.lastPosition") ?? "Last position"}: {JSON.stringify(entry.last_position)}
-                    </div>
-                  )}
-                </div>
-              );
-            })
-          )}
-        </div>
-      )}
-
-      {/* Admin tab */}
-      {tab === "admin" && adminSummary && (
-        <div>
-          <div style={{
-            display: "grid",
-            gridTemplateColumns: "repeat(auto-fit, minmax(140px, 1fr))",
-            gap: 12,
-            marginBottom: 24,
-          }}>
-            <StatCard
-              label={t("groupDetail.totalMembers") ?? "Members"}
-              value={String(adminSummary.total_members)}
-            />
-            <StatCard
-              label={t("groupDetail.started") ?? "Started"}
-              value={String(adminSummary.members_started)}
-            />
-            <StatCard
-              label={t("groupDetail.finished") ?? "Finished"}
-              value={String(adminSummary.members_finished)}
-            />
-            <StatCard
-              label={t("groupDetail.avgProgress") ?? "Avg Progress"}
-              value={`${Math.round(adminSummary.average_percentage)}%`}
-            />
-            <StatCard
-              label={t("groupDetail.avgTime") ?? "Avg Time"}
-              value={`${adminSummary.average_time_spent_hours}h`}
-            />
-          </div>
-
-          <h3 style={{ fontSize: 15, fontWeight: 600, color: "#1f2937", marginBottom: 12 }}>
-            {t("groupDetail.memberDetails") ?? "Member Details"}
-          </h3>
-          {adminSummary.member_details.map((m) => (
-            <div
-              key={m.user_id}
-              style={{
-                background: "#fff", borderRadius: 10, padding: isMobile ? 12 : 14,
-                marginBottom: 8, border: "1px solid #e5e7eb",
-                display: "flex", justifyContent: "space-between", alignItems: "center",
-              }}
-            >
-              <div>
-                <span style={{ fontSize: 14, fontWeight: 500, color: "#1f2937" }}>{m.user_email}</span>
-                <span style={{ fontSize: 12, color: "#9ca3af", marginLeft: 8 }}>
-                  {m.is_public ? "👁" : "🔒"}
-                </span>
-              </div>
-              <div style={{ display: "flex", gap: 16, fontSize: 13, color: "#6b7280" }}>
-                <span>Section {m.current_section}</span>
-                <span style={{ fontWeight: 600, color: "#4f46e5" }}>{Math.round(m.percentage)}%</span>
-                <span>⏱ {Math.round(m.time_spent_seconds / 60)}m</span>
-              </div>
-            </div>
-          ))}
-        </div>
-      )}
-    </div>
-  );
-}
-
-function StatCard({ label, value }: { label: string; value: string }) {
-  return (
-    <div style={{
-      background: "#fff", borderRadius: 10, padding: "14px 16px",
-      border: "1px solid #e5e7eb", textAlign: "center",
-    }}>
-      <div style={{ fontSize: 22, fontWeight: 700, color: "#4f46e5" }}>{value}</div>
-      <div style={{ fontSize: 12, color: "#6b7280", marginTop: 2 }}>{label}</div>
-    </div>
-  );
-}

frontend/src/pages/Library.tsx

@@ -242,7 +242,6 @@ export function LibraryPage() {
             <>
               <button onClick={() => navigate("/add")} style={{ ...TOUCH_TARGET, fontSize: 20, background: "none", border: "none", cursor: "pointer", padding: 8 }} title={t("library.addBook")}>➕</button>
               <button onClick={() => navigate("/bookmarks-notes")} style={{ ...TOUCH_TARGET, fontSize: 20, background: "none", border: "none", cursor: "pointer", padding: 8 }} title={t("library.bookmarks")}>🔖</button>
-              <button onClick={() => navigate("/groups")} style={{ ...TOUCH_TARGET, fontSize: 20, background: "none", border: "none", cursor: "pointer", padding: 8 }} title="Reading Groups">👥</button>
               <button onClick={() => navigate("/settings")} style={{ ...TOUCH_TARGET, fontSize: 20, background: "none", border: "none", cursor: "pointer", padding: 8 }} title={t("library.settings")}>⚙️</button>
               <button onClick={logout} style={{ ...TOUCH_TARGET, fontSize: 20, background: "none", border: "none", cursor: "pointer", padding: 8 }} title={t("library.logout")}>🚪</button>
             </>
@@ -250,7 +249,6 @@ export function LibraryPage() {
             <>
               <button onClick={() => navigate("/add")} className="btn">+ {t("library.addBook")}</button>
               <button onClick={() => navigate("/bookmarks-notes")} className="btn btn-secondary">{t("library.bookmarks")}</button>
-              <button onClick={() => navigate("/groups")} className="btn btn-secondary">👥 Reading Groups</button>
               <button onClick={() => navigate("/settings")} className="btn btn-secondary">{t("library.settings")}</button>
               <button onClick={logout} className="btn btn-danger">{t("library.logout")}</button>
             </>

frontend/src/pages/ReadingGroups.tsx

@@ -1,288 +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 { booksApi } from "../api/books";
-import type { ReadingGroupSummary } from "../types/groups";
-import type { EBookListItem } from "../types/book";
-import { useMediaQuery, BREAKPOINTS } from "../hooks/useMediaQuery";
-
-export function ReadingGroupsPage() {
-  const { t } = useTranslation();
-  const navigate = useNavigate();
-  const isMobile = useMediaQuery(BREAKPOINTS.md);
-
-  const [groups, setGroups] = useState<ReadingGroupSummary[]>([]);
-  const [ebooks, setEbooks] = useState<EBookListItem[]>([]);
-  const [loading, setLoading] = useState(true);
-  const [error, setError] = useState<string | null>(null);
-  const [showCreate, setShowCreate] = useState(false);
-  const [createName, setCreateName] = useState("");
-  const [createEbook, setCreateEbook] = useState<number | null>(null);
-  const [createDesc, setCreateDesc] = useState("");
-  const [creating, setCreating] = useState(false);
-
-  const loadGroups = useCallback(async () => {
-    try {
-      const data = await groupsApi.listGroups();
-      setGroups(data);
-      setError(null);
-    } catch (err) {
-      setError(err instanceof Error ? err.message : "Failed to load groups");
-    } finally {
-      setLoading(false);
-    }
-  }, []);
-
-  const loadEbooks = useCallback(async () => {
-    try {
-      const data = await booksApi.getEBooks();
-      setEbooks(data);
-    } catch {
-      // Ebook list is optional; groups page still works without it
-    }
-  }, []);
-
-  useEffect(() => {
-    void loadGroups();
-    void loadEbooks();
-  }, [loadGroups, loadEbooks]);
-
-  const handleCreate = useCallback(async () => {
-    if (!createName.trim() || createEbook === null) return;
-    setCreating(true);
-    try {
-      await groupsApi.createGroup({
-        name: createName.trim(),
-        ebook: createEbook,
-        description: createDesc.trim(),
-      });
-      setShowCreate(false);
-      setCreateName("");
-      setCreateEbook(null);
-      setCreateDesc("");
-      void loadGroups();
-    } catch (err) {
-      setError(err instanceof Error ? err.message : "Failed to create group");
-    } finally {
-      setCreating(false);
-    }
-  }, [createName, createEbook, createDesc, loadGroups]);
-
-  const containerStyle: React.CSSProperties = {
-    maxWidth: 720,
-    margin: "0 auto",
-    padding: isMobile ? 16 : 24,
-    minHeight: "100vh",
-    background: "#f8f9fa",
-  };
-
-  const headerBar: React.CSSProperties = {
-    display: "flex",
-    justifyContent: "space-between",
-    alignItems: "center",
-    marginBottom: 24,
-  };
-
-  const cardStyle: React.CSSProperties = {
-    background: "#fff",
-    borderRadius: 12,
-    padding: isMobile ? 14 : 18,
-    marginBottom: 12,
-    cursor: "pointer",
-    boxShadow: "0 1px 4px rgba(0,0,0,0.06)",
-    border: "1px solid #e5e7eb",
-  };
-
-  if (loading) {
-    return (
-      <div style={containerStyle}>
-        <div style={{ height: 24, width: 200, background: "#e5e7eb", borderRadius: 6, marginBottom: 24 }} />
-        {[1, 2, 3].map((i) => (
-          <div key={i} style={{ ...cardStyle, cursor: "default" }}>
-            <div style={{ height: 20, width: "60%", background: "#e5e7eb", borderRadius: 4, marginBottom: 8 }} />
-            <div style={{ height: 14, width: "40%", background: "#e5e7eb", borderRadius: 4 }} />
-          </div>
-        ))}
-      </div>
-    );
-  }
-
-  return (
-    <div style={containerStyle}>
-      <div style={headerBar}>
-        <h1 style={{ fontSize: isMobile ? 20 : 24, fontWeight: 700, color: "#1f2937", margin: 0 }}>
-          📚 {t("readingGroups.title") ?? "Reading Groups"}
-        </h1>
-        <button
-          onClick={() => setShowCreate(true)}
-          style={{
-            padding: isMobile ? "10px 18px" : "8px 18px",
-            borderRadius: 10,
-            border: "none",
-            background: "#4f46e5",
-            color: "#fff",
-            fontSize: 14,
-            fontWeight: 600,
-            cursor: "pointer",
-            minHeight: 40,
-          }}
-        >
-          + {t("readingGroups.create") ?? "New Group"}
-        </button>
-      </div>
-
-      {error && (
-        <div style={{ padding: "12px 16px", background: "#fef2f2", borderRadius: 8, color: "#b91c1c", marginBottom: 16, fontSize: 14 }}>
-          {error}
-        </div>
-      )}
-
-      {/* Create modal */}
-      {showCreate && (
-        <div style={{
-          position: "fixed", inset: 0, background: "rgba(0,0,0,0.4)",
-          display: "flex", alignItems: "center", justifyContent: "center", zIndex: 100,
-        }}>
-          <div style={{
-            background: "#fff", borderRadius: 16, padding: 24, maxWidth: 420, width: "90%",
-            boxShadow: "0 10px 40px rgba(0,0,0,0.15)",
-          }}>
-            <h2 style={{ fontSize: 18, fontWeight: 700, marginBottom: 16, color: "#1f2937" }}>
-              {t("readingGroups.createTitle") ?? "Create Reading Group"}
-            </h2>
-
-            <label style={{ fontSize: 13, color: "#6b7280", display: "block", marginBottom: 4 }}>
-              {t("readingGroups.groupName") ?? "Group Name"}
-            </label>
-            <input
-              type="text"
-              value={createName}
-              onChange={(e) => setCreateName(e.target.value)}
-              placeholder={t("readingGroups.namePlaceholder") ?? "e.g., Book Club June"}
-              style={{
-                width: "100%", padding: "10px 14px", borderRadius: 8, border: "1px solid #d1d5db",
-                fontSize: 14, marginBottom: 14, boxSizing: "border-box",
-              }}
-            />
-
-            <label style={{ fontSize: 13, color: "#6b7280", display: "block", marginBottom: 4 }}>
-              {t("readingGroups.selectBook") ?? "Select Book"}
-            </label>
-            <select
-              value={createEbook ?? ""}
-              onChange={(e) => setCreateEbook(e.target.value ? Number(e.target.value) : null)}
-              style={{
-                width: "100%", padding: "10px 14px", borderRadius: 8, border: "1px solid #d1d5db",
-                fontSize: 14, marginBottom: 14, boxSizing: "border-box", background: "#fff",
-              }}
-            >
-              <option value="">-- {t("readingGroups.choose") ?? "Choose"} --</option>
-              {ebooks.map((eb) => (
-                <option key={eb.id} value={eb.id}>
-                  {eb.title} {eb.author ? `— ${eb.author}` : ""}
-                </option>
-              ))}
-            </select>
-
-            <label style={{ fontSize: 13, color: "#6b7280", display: "block", marginBottom: 4 }}>
-              {t("readingGroups.description") ?? "Description"} ({t("common.optional") ?? "optional"})
-            </label>
-            <textarea
-              value={createDesc}
-              onChange={(e) => setCreateDesc(e.target.value)}
-              rows={3}
-              style={{
-                width: "100%", padding: "10px 14px", borderRadius: 8, border: "1px solid #d1d5db",
-                fontSize: 14, marginBottom: 18, boxSizing: "border-box", resize: "vertical",
-              }}
-            />
-
-            <div style={{ display: "flex", gap: 10, justifyContent: "flex-end" }}>
-              <button
-                onClick={() => setShowCreate(false)}
-                style={{
-                  padding: "10px 20px", borderRadius: 8, border: "1px solid #d1d5db",
-                  background: "#fff", color: "#374151", fontSize: 14, cursor: "pointer",
-                }}
-              >
-                {t("common.cancel") ?? "Cancel"}
-              </button>
-              <button
-                onClick={() => void handleCreate()}
-                disabled={creating || !createName.trim() || createEbook === null}
-                style={{
-                  padding: "10px 20px", borderRadius: 8, border: "none",
-                  background: (!createName.trim() || createEbook === null) ? "#9ca3af" : "#4f46e5",
-                  color: "#fff", fontSize: 14, fontWeight: 600, cursor: (!createName.trim() || createEbook === null) ? "not-allowed" : "pointer",
-                }}
-              >
-                {creating ? (t("common.creating") ?? "Creating...") : (t("readingGroups.create") ?? "Create")}
-              </button>
-            </div>
-          </div>
-        </div>
-      )}
-
-      {/* Group list */}
-      {groups.length === 0 ? (
-        <div style={{ textAlign: "center", padding: "60px 20px", color: "#6b7280" }}>
-          <div style={{ fontSize: 48, marginBottom: 12 }}>📖</div>
-          <p style={{ fontSize: 16, marginBottom: 16 }}>
-            {t("readingGroups.empty") ?? "No reading groups yet. Create one to read together!"}
-          </p>
-        </div>
-      ) : (
-        groups.map((g) => (
-          <div
-            key={g.id}
-            style={cardStyle}
-            onClick={() => navigate(`/groups/${g.id}`)}
-          >
-            <div style={{ display: "flex", justifyContent: "space-between", alignItems: "flex-start" }}>
-              <div>
-                <h2 style={{ fontSize: isMobile ? 16 : 17, fontWeight: 600, color: "#1f2937", margin: "0 0 4px" }}>
-                  {g.name}
-                </h2>
-                <p style={{ fontSize: 13, color: "#6b7280", margin: "0 0 6px" }}>
-                  {g.ebook_title} {g.ebook_author ? `— ${g.ebook_author}` : ""}
-                </p>
-              </div>
-              <span style={{
-                fontSize: 12, color: "#4f46e5", background: "#eef2ff",
-                padding: "2px 10px", borderRadius: 999, whiteSpace: "nowrap",
-                minHeight: 24, display: "inline-flex", alignItems: "center",
-              }}>
-                {g.member_count} {g.member_count === 1
-                  ? (t("readingGroups.member") ?? "member")
-                  : (t("readingGroups.members") ?? "members")}
-              </span>
-            </div>
-
-            {g.my_progress && (
-              <div style={{ marginTop: 8, display: "flex", alignItems: "center", gap: 8 }}>
-                <div style={{
-                  flex: 1, height: 6, borderRadius: 3, background: "#e5e7eb", overflow: "hidden",
-                }}>
-                  <div style={{
-                    height: "100%", width: `${Math.min(100, g.my_progress.percentage)}%`,
-                    background: "#4f46e5", borderRadius: 3, transition: "width 0.3s ease",
-                  }} />
-                </div>
-                <span style={{ fontSize: 12, color: "#6b7280", whiteSpace: "nowrap" }}>
-                  {g.my_progress.section_label}
-                </span>
-              </div>
-            )}
-
-            {g.description && (
-              <p style={{ fontSize: 13, color: "#9ca3af", margin: "8px 0 0", lineHeight: 1.5 }}>
-                {g.description}
-              </p>
-            )}
-          </div>
-        ))
-      )}
-    </div>
-  );
-}

frontend/src/pages/RecommendationPage.tsx

@@ -0,0 +1,601 @@
+import React, { useCallback, useEffect, useState } from "react";
+import { useNavigate, useParams } from "react-router-dom";
+import { useTranslation } from "react-i18n-lite";
+import { schedulesApi } from "../api/books";
+import { booksApi } from "../api/books";
+import type {
+  BookChapter,
+  EBookListItem,
+  MeetingSection,
+  ReadingSchedule,
+} from "../types/book";
+import { useMediaQuery, BREAKPOINTS } from "../hooks/useMediaQuery";
+
+/* ---- drag-and-drop types ---- */
+interface DragData {
+  chapterId: number;
+  sourceMeetingId: number | null; // null = unassigned
+}
+
+function formatTime(minutes: number): string {
+  if (minutes < 60) return `${minutes} min`;
+  const h = Math.floor(minutes / 60);
+  const m = minutes % 60;
+  return m > 0 ? `${h}h ${m}m` : `${h}h`;
+}
+
+export function RecommendationPage() {
+  const { t } = useTranslation();
+  const { ebookId } = useParams<{ ebookId: string }>();
+  const navigate = useNavigate();
+  const isMobile = useMediaQuery(BREAKPOINTS.md);
+
+  const [ebook, setEbook] = useState<EBookListItem | null>(null);
+  const [schedule, setSchedule] = useState<ReadingSchedule | null>(null);
+  const [loading, setLoading] = useState(true);
+  const [generating, setGenerating] = useState(false);
+  const [error, setError] = useState<string | null>(null);
+  const [draggedChapter, setDraggedChapter] = useState<DragData | null>(null);
+  const [dropTarget, setDropTarget] = useState<number | null>(null);
+
+  const bookId = Number(ebookId);
+  const validId = !Number.isNaN(bookId);
+
+  const loadData = useCallback(async () => {
+    if (!validId) {
+      setError("Invalid ebook ID.");
+      setLoading(false);
+      return;
+    }
+    setLoading(true);
+    setError(null);
+    try {
+      const [ebookData, schedules] = await Promise.all([
+        booksApi.getEBook(bookId),
+        schedulesApi.getSchedules(),
+      ]);
+      setEbook({
+        id: ebookData.id,
+        title: ebookData.title,
+        author: ebookData.author,
+        filename: ebookData.filename,
+        format: ebookData.format,
+        page_count: ebookData.page_count,
+        cover_image:
+          typeof ebookData.cover_image === "string" ? ebookData.cover_image : null,
+        created_at: ebookData.created_at,
+        progress: ebookData.progress?.current_position ?? null,
+        started: ebookData.progress != null,
+      });
+      const existing = schedules.find((s) => s.ebook === bookId);
+      setSchedule(existing ?? null);
+    } catch (err) {
+      setError(err instanceof Error ? err.message : "Failed to load data.");
+    } finally {
+      setLoading(false);
+    }
+  }, [bookId, validId]);
+
+  useEffect(() => {
+    void loadData();
+  }, [loadData]);
+
+  const handleGenerate = useCallback(async () => {
+    if (!validId) return;
+    setGenerating(true);
+    setError(null);
+    try {
+      const newSchedule = await schedulesApi.generateRecommendations({
+        ebook_id: bookId,
+        meeting_count: 4,
+      });
+      setSchedule(newSchedule);
+    } catch (err) {
+      setError(err instanceof Error ? err.message : "Failed to generate recommendations.");
+    } finally {
+      setGenerating(false);
+    }
+  }, [bookId, validId]);
+
+  const handleRegenerate = useCallback(async () => {
+    if (!schedule) return;
+    setGenerating(true);
+    setError(null);
+    try {
+      const updated = await schedulesApi.regenerateRecommendations(schedule.id);
+      setSchedule(updated);
+    } catch (err) {
+      setError(err instanceof Error ? err.message : "Failed to regenerate recommendations.");
+    } finally {
+      setGenerating(false);
+    }
+  }, [schedule]);
+
+  const handleConfirm = useCallback(async () => {
+    if (!schedule) return;
+    setError(null);
+    try {
+      const updated = await schedulesApi.confirmSchedule(schedule.id);
+      setSchedule(updated);
+    } catch (err) {
+      setError(err instanceof Error ? err.message : "Failed to confirm schedule.");
+    }
+  }, [schedule]);
+
+  /* ---- drag-and-drop handlers ---- */
+  const handleDragStart = useCallback(
+    (chapterId: number, sourceMeetingId: number | null) => (e: React.DragEvent) => {
+      setDraggedChapter({ chapterId, sourceMeetingId });
+      e.dataTransfer.effectAllowed = "move";
+      e.dataTransfer.setData("text/plain", String(chapterId));
+    },
+    [],
+  );
+
+  const handleDragOver = useCallback(
+    (targetMeetingId: number) => (e: React.DragEvent) => {
+      e.preventDefault();
+      e.dataTransfer.dropEffect = "move";
+      setDropTarget(targetMeetingId);
+    },
+    [],
+  );
+
+  const handleDragLeave = useCallback(() => {
+    setDropTarget(null);
+  }, []);
+
+  const handleDrop = useCallback(
+    async (targetMeetingId: number) => {
+      setDropTarget(null);
+      if (!draggedChapter || !schedule) return;
+
+      const { chapterId, sourceMeetingId } = draggedChapter;
+      setDraggedChapter(null);
+
+      // Same meeting — no-op
+      if (sourceMeetingId === targetMeetingId) return;
+
+      // Optimistically update UI
+      const updatedMeetings = schedule.meetings.map((m) => ({
+        ...m,
+        chapter_ids: [...m.chapter_ids],
+        chapters: [...m.chapters],
+      }));
+
+      // Remove from source
+      if (sourceMeetingId !== null) {
+        const source = updatedMeetings.find((m) => m.id === sourceMeetingId);
+        if (source) {
+          source.chapter_ids = source.chapter_ids.filter((id) => id !== chapterId);
+          source.chapters = source.chapters.filter((ch) => ch.id !== chapterId);
+        }
+      }
+
+      // Add to target
+      const target = updatedMeetings.find((m) => m.id === targetMeetingId);
+      if (target && !target.chapter_ids.includes(chapterId)) {
+        target.chapter_ids = [...target.chapter_ids, chapterId];
+        // Find chapter data
+        const allChapters = schedule.meetings.flatMap((m) => m.chapters);
+        const movedChapter = allChapters.find((ch) => ch.id === chapterId);
+        if (movedChapter) {
+          target.chapters = [...target.chapters, movedChapter];
+        }
+      }
+
+      setSchedule({ ...schedule, meetings: updatedMeetings });
+
+      // Persist to backend
+      try {
+        await schedulesApi.updateMeeting(schedule.id, targetMeetingId, {
+          chapter_ids: target?.chapter_ids ?? [],
+        });
+        if (sourceMeetingId !== null) {
+          const source = updatedMeetings.find((m) => m.id === sourceMeetingId);
+          if (source) {
+            await schedulesApi.updateMeeting(schedule.id, sourceMeetingId, {
+              chapter_ids: source.chapter_ids,
+            });
+          }
+        }
+      } catch (err) {
+        setError("Failed to save changes. Please try again.");
+        // Reload to reset
+        void loadData();
+      }
+    },
+    [draggedChapter, schedule, loadData],
+  );
+
+  const handleUnassignDrop = useCallback(
+    async () => {
+      setDropTarget(null);
+      if (!draggedChapter || !schedule) return;
+      const { chapterId, sourceMeetingId } = draggedChapter;
+      setDraggedChapter(null);
+
+      if (sourceMeetingId === null) return;
+
+      // Remove from source
+      const updatedMeetings = schedule.meetings.map((m) => ({
+        ...m,
+        chapter_ids: [...m.chapter_ids],
+        chapters: [...m.chapters],
+      }));
+      const source = updatedMeetings.find((m) => m.id === sourceMeetingId);
+      if (source) {
+        source.chapter_ids = source.chapter_ids.filter((id) => id !== chapterId);
+        source.chapters = source.chapters.filter((ch) => ch.id !== chapterId);
+      }
+
+      setSchedule({ ...schedule, meetings: updatedMeetings });
+
+      try {
+        await schedulesApi.updateMeeting(schedule.id, sourceMeetingId, {
+          chapter_ids: source?.chapter_ids ?? [],
+        });
+      } catch {
+        setError("Failed to save changes.");
+        void loadData();
+      }
+    },
+    [draggedChapter, schedule, loadData],
+  );
+
+  const handleDragEnd = useCallback(() => {
+    setDraggedChapter(null);
+    setDropTarget(null);
+  }, []);
+
+  /* ---- styles ---- */
+  const containerStyle: React.CSSProperties = {
+    maxWidth: 1200,
+    margin: "0 auto",
+    padding: isMobile ? 12 : 24,
+    minHeight: "100vh",
+    background: "#f8f9fa",
+  };
+
+  const headerStyle: React.CSSProperties = {
+    display: "flex",
+    alignItems: "center",
+    gap: 12,
+    marginBottom: 24,
+    flexWrap: "wrap",
+  };
+
+  const backBtnStyle: React.CSSProperties = {
+    padding: "8px 16px",
+    borderRadius: 8,
+    border: "1px solid #e5e7eb",
+    background: "#fff",
+    color: "#374151",
+    fontSize: 14,
+    cursor: "pointer",
+  };
+
+  const btnPrimaryStyle: React.CSSProperties = {
+    padding: "10px 24px",
+    borderRadius: 8,
+    border: "none",
+    background: "#4f46e5",
+    color: "#fff",
+    fontSize: 14,
+    fontWeight: 600,
+    cursor: "pointer",
+    opacity: generating ? 0.7 : 1,
+    minHeight: 44,
+  };
+
+  const confirmBtnStyle: React.CSSProperties = {
+    ...btnPrimaryStyle,
+    background: "#16a34a",
+  };
+
+  const meetingsGridStyle: React.CSSProperties = {
+    display: "grid",
+    gridTemplateColumns: isMobile
+      ? "1fr"
+      : `repeat(${schedule?.meeting_count ?? 4}, 1fr)`,
+    gap: 16,
+    marginTop: 16,
+  };
+
+  const meetingCardStyle = (isDropTarget: boolean): React.CSSProperties => ({
+    background: isDropTarget ? "#eef2ff" : "#fff",
+    borderRadius: 12,
+    border: `2px solid ${isDropTarget ? "#4f46e5" : "#e5e7eb"}`,
+    padding: 16,
+    minHeight: 200,
+    transition: "border-color 0.2s, background 0.2s",
+  });
+
+  const chapterChipStyle: React.CSSProperties = {
+    background: "#f3f4f6",
+    borderRadius: 8,
+    padding: "8px 12px",
+    marginBottom: 8,
+    cursor: "grab",
+    fontSize: 13,
+    color: "#374151",
+    border: "1px solid #e5e7eb",
+    userSelect: "none" as const,
+  };
+
+  /* ---- render ---- */
+
+  if (!validId) {
+    return (
+      <div style={containerStyle}>
+        <p style={{ color: "#ef4444" }}>Invalid ebook ID.</p>
+      </div>
+    );
+  }
+
+  if (loading) {
+    return (
+      <div style={containerStyle}>
+        <div style={{ display: "flex", justifyContent: "center", alignItems: "center", minHeight: 400 }}>
+          <p style={{ color: "#888" }}>{t("common.loading")}</p>
+        </div>
+      </div>
+    );
+  }
+
+  if (error) {
+    return (
+      <div style={containerStyle}>
+        <button onClick={() => navigate(-1)} style={backBtnStyle}>← Back</button>
+        <div style={{ textAlign: "center", padding: 60 }}>
+          <p style={{ color: "#ef4444", marginBottom: 16 }}>{error}</p>
+          <button onClick={() => void loadData()} style={btnPrimaryStyle}>
+            {t("common.retry")}
+          </button>
+        </div>
+      </div>
+    );
+  }
+
+  return (
+    <div style={containerStyle}>
+      {/* Header */}
+      <div style={headerStyle}>
+        <button onClick={() => navigate("/")} style={backBtnStyle}>
+          ← {isMobile ? "Library" : "Back to Library"}
+        </button>
+        <div style={{ flex: 1 }}>
+          <h1 style={{ fontSize: isMobile ? 18 : 24, margin: 0, color: "#1f2937" }}>
+            Reading Schedule
+          </h1>
+          {ebook && (
+            <p style={{ color: "#6b7280", fontSize: 14, margin: "4px 0 0" }}>
+              {ebook.title}{ebook.author ? ` — ${ebook.author}` : ""}
+            </p>
+          )}
+        </div>
+        {!schedule && (
+          <button onClick={handleGenerate} style={btnPrimaryStyle} disabled={generating}>
+            {generating ? "Generating..." : "Generate Recommendations"}
+          </button>
+        )}
+        {schedule && (
+          <div style={{ display: "flex", gap: 8, flexWrap: "wrap" }}>
+            <button onClick={handleRegenerate} style={btnPrimaryStyle} disabled={generating}>
+              {generating ? "Regenerating..." : "Regenerate"}
+            </button>
+            {!schedule.confirmed && (
+              <button onClick={handleConfirm} style={confirmBtnStyle}>
+                Confirm Schedule
+              </button>
+            )}
+          </div>
+        )}
+      </div>
+
+      {/* Status badge */}
+      {schedule && (
+        <div style={{ marginBottom: 16 }}>
+          <span style={{
+            padding: "4px 12px",
+            borderRadius: 999,
+            fontSize: 13,
+            fontWeight: 600,
+            background: schedule.confirmed ? "#dcfce7" : "#fef3c7",
+            color: schedule.confirmed ? "#16a34a" : "#b45309",
+          }}>
+            {schedule.confirmed ? "✓ Confirmed" : "Draft — drag chapters to adjust"}
+          </span>
+        </div>
+      )}
+
+      {/* No schedule yet */}
+      {!schedule && (
+        <div style={{ textAlign: "center", padding: "60px 16px" }}>
+          <div style={{ fontSize: 48, marginBottom: 16 }}>📅</div>
+          <h2 style={{ fontSize: 20, color: "#1f2937", marginBottom: 8 }}>
+            No Schedule Yet
+          </h2>
+          <p style={{ color: "#6b7280", marginBottom: 24, maxWidth: 400, margin: "0 auto 24px" }}>
+            Generate a reading schedule to split this book into balanced weekly assignments for your group.
+          </p>
+          <button onClick={handleGenerate} style={btnPrimaryStyle} disabled={generating}>
+            {generating ? "Generating..." : "Generate Recommendations"}
+          </button>
+        </div>
+      )}
+
+      {/* Schedule meetings */}
+      {schedule && (
+        <>
+          {/* Unassigned drop zone */}
+          <div
+            style={{
+              padding: "12px 16px",
+              background: dropTarget === null && draggedChapter ? "#fef2f2" : "#f9fafb",
+              borderRadius: 8,
+              border: `2px dashed ${dropTarget === null && draggedChapter ? "#ef4444" : "#d1d5db"}`,
+              marginBottom: 16,
+              textAlign: "center",
+              color: "#6b7280",
+              fontSize: 13,
+              minHeight: 44,
+              display: "flex",
+              alignItems: "center",
+              justifyContent: "center",
+              transition: "all 0.2s",
+            }}
+            onDragOver={(e) => { e.preventDefault(); e.dataTransfer.dropEffect = "move"; setDropTarget(null); }}
+            onDrop={handleUnassignDrop}
+            onDragLeave={() => setDropTarget(null)}
+          >
+            {dropTarget === null && draggedChapter
+              ? "Drop here to unassign"
+              : "Drag chapters here to unassign from meetings"}
+          </div>
+
+          {/* Meetings grid */}
+          <div style={meetingsGridStyle}>
+            {schedule.meetings.map((meeting, idx) => (
+              <MeetingColumn
+                key={meeting.id}
+                meeting={meeting}
+                index={idx}
+                isDropTarget={dropTarget === meeting.id}
+                isConfirmed={schedule.confirmed}
+                onDragStart={handleDragStart}
+                onDragOver={handleDragOver(meeting.id)}
+                onDragLeave={handleDragLeave}
+                onDrop={() => void handleDrop(meeting.id)}
+                onDragEnd={handleDragEnd}
+              />
+            ))}
+          </div>
+        </>
+      )}
+
+      {/* Drag overlay instruction */}
+      {draggedChapter && (
+        <div style={{
+          position: "fixed",
+          bottom: 24,
+          left: "50%",
+          transform: "translateX(-50%)",
+          background: "#1f2937",
+          color: "#fff",
+          padding: "12px 24px",
+          borderRadius: 12,
+          fontSize: 14,
+          boxShadow: "0 4px 16px rgba(0,0,0,0.2)",
+          zIndex: 999,
+        }}>
+          Drop the chapter into a meeting column
+        </div>
+      )}
+    </div>
+  );
+}
+
+/* ---- Meeting Column Sub-component ---- */
+
+interface MeetingColumnProps {
+  meeting: MeetingSection;
+  index: number;
+  isDropTarget: boolean;
+  isConfirmed: boolean;
+  onDragStart: (chapterId: number, sourceMeetingId: number | null) => (e: React.DragEvent) => void;
+  onDragOver: (e: React.DragEvent) => void;
+  onDragLeave: () => void;
+  onDrop: () => void;
+  onDragEnd: () => void;
+}
+
+function MeetingColumn({
+  meeting,
+  index,
+  isDropTarget,
+  isConfirmed,
+  onDragStart,
+  onDragOver,
+  onDragLeave,
+  onDrop,
+  onDragEnd,
+}: MeetingColumnProps) {
+  const chapterCount = meeting.chapter_ids.length;
+
+  const cardStyle: React.CSSProperties = {
+    background: isDropTarget ? "#eef2ff" : "#fff",
+    borderRadius: 12,
+    border: `2px solid ${isDropTarget ? "#4f46e5" : "#e5e7eb"}`,
+    overflow: "hidden",
+    transition: "border-color 0.2s, background 0.2s",
+  };
+
+  const headerStyle: React.CSSProperties = {
+    padding: "12px 16px",
+    background: "#f9fafb",
+    borderBottom: "1px solid #e5e7eb",
+  };
+
+  const bodyStyle: React.CSSProperties = {
+    padding: "12px 16px",
+    minHeight: 120,
+  };
+
+  return (
+    <div style={cardStyle}>
+      <div style={headerStyle}>
+        <div style={{ fontWeight: 700, color: "#1f2937", fontSize: 15, marginBottom: 4 }}>
+          Week {index + 1}
+        </div>
+        <div style={{ display: "flex", gap: 16, fontSize: 12, color: "#6b7280" }}>
+          <span>{chapterCount} {chapterCount === 1 ? "chapter" : "chapters"}</span>
+          <span>{formatTime(meeting.estimated_time_minutes)}</span>
+        </div>
+      </div>
+      <div
+        style={bodyStyle}
+        onDragOver={isConfirmed ? undefined : onDragOver}
+        onDragLeave={isConfirmed ? undefined : onDragLeave}
+        onDrop={isConfirmed ? undefined : onDrop}
+      >
+        {meeting.chapters.length === 0 && (
+          <div style={{
+            color: "#9ca3af",
+            fontSize: 13,
+            textAlign: "center",
+            padding: "20px 0",
+            fontStyle: "italic",
+          }}>
+            {isDropTarget ? "Drop here" : "No chapters assigned"}
+          </div>
+        )}
+        {meeting.chapters.map((chapter) => (
+          <div
+            key={`${meeting.id}-${chapter.id}`}
+            draggable={!isConfirmed}
+            onDragStart={isConfirmed ? undefined : onDragStart(chapter.id, meeting.id)}
+            onDragEnd={isConfirmed ? undefined : onDragEnd}
+            style={{
+              background: "#f3f4f6",
+              borderRadius: 8,
+              padding: "8px 12px",
+              marginBottom: 8,
+              cursor: isConfirmed ? "default" : "grab",
+              fontSize: 13,
+              color: "#374151",
+              border: "1px solid #e5e7eb",
+              userSelect: "none" as const,
+              opacity: isConfirmed ? 0.8 : 1,
+            }}
+          >
+            <div style={{ fontWeight: 600, marginBottom: 2 }}>{chapter.title}</div>
+            {chapter.href && (
+              <div style={{ fontSize: 11, color: "#9ca3af" }}>{chapter.href}</div>
+            )}
+          </div>
+        ))}
+      </div>
+    </div>
+  );
+}

frontend/src/types/book.ts

@@ -102,3 +102,27 @@ export interface BookSearchParams {
   page?: number;
   page_size?: number;
 }
+
+export interface MeetingSection {
+  id: number;
+  meeting_index: number;
+  title: string;
+  estimated_time_minutes: number;
+  chapter_ids: number[];
+  chapters: BookChapter[];
+}
+
+export interface ReadingSchedule {
+  id: number;
+  ebook: number;
+  meeting_count: number;
+  confirmed: boolean;
+  meetings: MeetingSection[];
+  created_at: string;
+  updated_at: string;
+}
+
+export interface GenerateRecommendationsRequest {
+  ebook_id: number;
+  meeting_count?: number;
+}

frontend/src/types/groups.ts

@@ -1,104 +0,0 @@
-/* ── Reading Groups ── */
-
-export interface MemberProgressPublic {
-  user_id: number;
-  user_email: string;
-  current_section: number;
-  total_sections: number;
-  section_label: string;
-  percentage: number;
-  time_spent_seconds: number;
-  updated_at: string;
-}
-
-export interface MemberProgressDetail {
-  id: number;
-  user_id: number;
-  user_email: string;
-  current_section: number;
-  total_sections: number;
-  section_label: string;
-  percentage: number;
-  time_spent_seconds: number;
-  last_position: Record<string, unknown>;
-  is_public: boolean;
-  updated_at: string;
-}
-
-export interface MemberProgressPrivateStub {
-  user_id: number;
-  user_email: string;
-  is_public: false;
-  note: string;
-}
-
-export type MemberProgressEntry =
-  | MemberProgressDetail
-  | MemberProgressPublic
-  | MemberProgressPrivateStub;
-
-export interface GroupMember {
-  id: number;
-  user_id: number;
-  user_email: string;
-  role: "member" | "admin";
-  joined_at: string;
-  progress: MemberProgressPublic | { is_public: false; note: string } | null;
-}
-
-export interface ReadingGroupSummary {
-  id: number;
-  name: string;
-  ebook: number;
-  ebook_title: string;
-  ebook_author: string;
-  created_by_email: string;
-  description: string;
-  member_count: number;
-  my_progress: {
-    current_section: number;
-    percentage: number;
-    time_spent_seconds: number;
-    section_label: string;
-  } | null;
-  created_at: string;
-  updated_at: string;
-}
-
-export interface ReadingGroupDetail extends ReadingGroupSummary {
-  members: GroupMember[];
-}
-
-export interface CreateGroupPayload {
-  name: string;
-  ebook: number;
-  description?: string;
-}
-
-export interface UpdateProgressPayload {
-  current_section: number;
-  percentage?: number;
-  time_spent_delta?: number;
-  last_position?: Record<string, unknown>;
-  is_public?: boolean;
-}
-
-export interface AdminProgressSummary {
-  group_id: number;
-  group_name: string;
-  ebook_title: string;
-  total_members: number;
-  members_started: number;
-  members_finished: number;
-  average_percentage: number;
-  average_time_spent_hours: number;
-  member_details: {
-    user_id: number;
-    user_email: string;
-    current_section: number;
-    percentage: number;
-    time_spent_seconds: number;
-    is_public: boolean;
-    updated_at: string;
-  }[];
-}

packages/shared/src/types.ts

@@ -216,35 +216,3 @@ export interface ApiError {
   detail?: string;
   [key: string]: unknown;
 }
-
-// ---- Reading Groups ----
-
-export interface ReadingGroupSummary {
-  id: number;
-  name: string;
-  ebook: number;
-  ebook_title: string;
-  ebook_author: string;
-  created_by_email: string;
-  description: string;
-  member_count: number;
-  my_progress: {
-    current_section: number;
-    percentage: number;
-    time_spent_seconds: number;
-    section_label: string;
-  } | null;
-  created_at: string;
-  updated_at: string;
-}
-
-export interface MemberProgressPublic {
-  user_id: number;
-  user_email: string;
-  current_section: number;
-  total_sections: number;
-  section_label: string;
-  percentage: number;
-  time_spent_seconds: number;
-  updated_at: string;
-}

packages/shared/src/utils.ts

@@ -114,13 +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/${id}/`,
-    membersProgress: (id: number) => `/api/groups/${id}/members/progress/`,
-    myProgress: (id: number) => `/api/groups/${id}/progress/`,
-    progressSummary: (id: number) => `/api/groups/${id}/progress/summary/`,
-    join: (id: number) => `/api/groups/${id}/join/`,
-    leave: (id: number) => `/api/groups/${id}/leave/`,
-  },
 } as const;