"""
Trello Plugin — Hermes Agent tool definitions.

Each function decorated with ``@tool`` registers itself as a Hermes tool
that the agent can invoke during a conversation.
"""

from __future__ import annotations

import json
import os
from typing import Any

from trello_plugin.client import TrelloClient

# ---------------------------------------------------------------------------
# Module-level client (lazily initialised so env vars can be overridden)
# ---------------------------------------------------------------------------

_client: TrelloClient | None = None


def _get_client() -> TrelloClient:
    global _client  # noqa: PLW0603
    api_key = os.environ.get("TRELLO_API_KEY", "")
    token = os.environ.get("TRELLO_TOKEN", "")
    if _client is None or _client.api_key != api_key or _client.token != token:
        _client = TrelloClient(api_key=api_key, token=token)
    return _client


# ---------------------------------------------------------------------------
# Tool helpers
# ---------------------------------------------------------------------------

def _respond(data: dict[str, Any]) -> str:
    """Wrap a result dict in a JSON string, the Hermes tool contract."""
    return json.dumps(data, indent=2)


# ---------------------------------------------------------------------------
# Tools
# ---------------------------------------------------------------------------

def trello_verify_credentials() -> str:
    """Verify that the Trello API key and token are valid.

    Checks the ``TRELLO_API_KEY`` and ``TRELLO_TOKEN`` environment variables
    and attempts a test call to the Trello API. Returns the authenticated
    user's Trello username on success.
    """
    client = _get_client()
    result = client.verify_credentials()
    return _respond(result)


def trello_list_boards() -> str:
    """List all Trello boards accessible to the authenticated user.

    Requires ``TRELLO_API_KEY`` and ``TRELLO_TOKEN`` to be set.
    Returns board id, name, URL, and whether the board is closed/starred.
    """
    client = _get_client()
    result = client.list_boards()
    return _respond(result)


def trello_disconnect() -> str:
    """Disconnect from Trello by clearing credentials from memory.

    This does NOT revoke the Trello token — invalidate it via
    Trello's account settings if full revocation is desired.
    """
    global _client  # noqa: PLW0603
    _client = None
    return _respond({"success": True, "message": "Trello credentials cleared from memory. Next tool call will re-read TRELLO_API_KEY and TRELLO_TOKEN from environment and reconnect automatically."})


# ---------------------------------------------------------------------------
# Plugin metadata (used by Hermes plugin loader)
# ---------------------------------------------------------------------------

PLUGIN_NAME = "trello-plugin"
PLUGIN_DESCRIPTION = "Hermes Agent plugin for Trello board integration"
PLUGIN_VERSION = "0.1.0"
PLUGIN_TOOLS = [
    trello_verify_credentials,
    trello_list_boards,
    trello_disconnect,
]
PLUGIN_REQUIRES_ENV = ["TRELLO_API_KEY", "TRELLO_TOKEN"]


def check_requirements() -> bool:
    """Return True when both Trello env vars are present."""
    return TrelloClient.check_requirements()