from .common import (
    MAX_FEED_MESSAGES,
    current_user,
    jsonify,
    request,
    get_db,
    build_feed_payload,
    room_by_id,
    can_access_room,
    get_channel_by_id,
    can_access_channel,
    validate_dm_access,
)


def register_feed_routes(app):
    @app.route("/api/feed")
    def get_feed():
        user = current_user()
        after_raw = request.args.get("after_id", "").strip()
        after_id = 0

        if after_raw:
            try:
                after_id = max(0, int(after_raw))
            except ValueError:
                return jsonify({"error": "after_id must be a non-negative integer."}), 400

        base_select = f"""
            SELECT
                m.id,
                m.room_id,
                m.channel_id,
                m.direct_conversation_id,
                m.user_id,
                m.username,
                m.text,
                m.created_at,
                m.attachment_id,
                m.parent_message_id,
                (
                    SELECT COUNT(*)
                    FROM messages AS thread_reply
                    WHERE thread_reply.parent_message_id = m.id
                ) AS thread_reply_count,
                r.slug AS room_slug,
                r.name AS room_name,
                r.visibility AS room_visibility,
                c.slug AS channel_slug,
                c.name AS channel_name,
                t.slug AS team_slug,
                t.name AS team_name,
                a.original_name AS attachment_original_name,
                a.mime_type AS attachment_mime_type,
                a.size_bytes AS attachment_size_bytes,
                u.role AS user_role,
                us.name_color AS user_name_color
            FROM messages AS m
            JOIN users AS u
                ON u.id = m.user_id
            LEFT JOIN user_settings AS us
                ON us.user_id = u.id
            LEFT JOIN rooms AS r
                ON r.id = m.room_id
            LEFT JOIN channels AS c
                ON c.id = m.channel_id
               AND c.is_active = 1
            LEFT JOIN teams AS t
                ON t.id = c.team_id
               AND t.is_active = 1
            LEFT JOIN attachments AS a
                ON a.id = m.attachment_id
        """

        params = []
        if user and user["role"] in {"moderator", "admin"}:
            access_clause = """
                (
                    (m.direct_conversation_id IS NULL AND r.id IS NOT NULL AND r.is_active = 1)
                    OR
                    (m.direct_conversation_id IS NULL AND c.id IS NOT NULL AND c.is_active = 1 AND t.is_active = 1)
                    OR
                    (
                        m.direct_conversation_id IS NOT NULL
                        AND EXISTS (
                            SELECT 1
                            FROM direct_conversation_members AS dcm
                            WHERE dcm.direct_conversation_id = m.direct_conversation_id
                              AND dcm.user_id = ?
                        )
                    )
                )
            """
            params.append(user["id"])
        elif user:
            access_clause = """
                (
                    (
                        m.direct_conversation_id IS NULL
                        AND r.id IS NOT NULL
                        AND r.is_active = 1
                        AND (
                            r.visibility = 'public'
                            OR EXISTS (
                                SELECT 1
                                FROM room_members AS rm
                                WHERE rm.room_id = r.id
                                  AND rm.user_id = ?
                            )
                        )
                    )
                    OR
                    (
                        m.direct_conversation_id IS NULL
                        AND c.id IS NOT NULL
                        AND c.is_active = 1
                        AND t.is_active = 1
                        AND c.legacy_room_id IS NULL
                        AND EXISTS (
                            SELECT 1
                            FROM team_members AS tm
                            WHERE tm.team_id = c.team_id
                              AND tm.user_id = ?
                        )
                    )
                    OR
                    (
                        m.direct_conversation_id IS NOT NULL
                        AND EXISTS (
                            SELECT 1
                            FROM direct_conversation_members AS dcm
                            WHERE dcm.direct_conversation_id = m.direct_conversation_id
                              AND dcm.user_id = ?
                        )
                    )
                )
            """
            params.extend([user["id"], user["id"], user["id"]])
        else:
            access_clause = """
                m.direct_conversation_id IS NULL
                AND r.id IS NOT NULL
                AND r.is_active = 1
                AND r.visibility = 'public'
            """

        if after_raw:
            query = f"""
                {base_select}
                WHERE m.parent_message_id IS NULL
                  AND {access_clause}
                  AND m.id > ?
                ORDER BY m.id ASC
                LIMIT ?
            """
            query_params = [*params, after_id, MAX_FEED_MESSAGES]

            with get_db() as db:
                rows = db.execute(query, tuple(query_params)).fetchall()

            entries = [build_feed_payload(row, user) for row in rows]
            latest_id = entries[-1]["id"] if entries else after_id
            return jsonify(
                {
                    "entries": entries,
                    "latest_id": latest_id,
                    "has_more": len(entries) == MAX_FEED_MESSAGES,
                }
            )

        query = f"""
            SELECT *
            FROM (
                {base_select}
                WHERE m.parent_message_id IS NULL
                  AND {access_clause}
                ORDER BY m.id DESC
                LIMIT ?
            )
            ORDER BY id ASC
        """
        query_params = [*params, MAX_FEED_MESSAGES]

        with get_db() as db:
            rows = db.execute(query, tuple(query_params)).fetchall()

        entries = [build_feed_payload(row, user) for row in rows]
        latest_id = entries[-1]["id"] if entries else 0
        return jsonify({"entries": entries, "latest_id": latest_id, "has_more": False})