"""User self-service usage endpoints."""
import logging
from datetime import datetime, timezone
from quart import Blueprint, jsonify, request
from app.auth.quart_jwt import jwt_required, get_jwt_identity
from app.utils import active_required
from app.models.usage_event import UsageEvent
from app.db import get_db

logger = logging.getLogger(__name__)
usage_bp = Blueprint('usage', __name__)


def _month_start() -> datetime:
    now = datetime.now(timezone.utc)
    return now.replace(day=1, hour=0, minute=0, second=0, microsecond=0)


@usage_bp.route('/me', methods=['GET'])
@jwt_required()
async def my_usage():
    """GET /api/usage/me — current user's own MTD cost summary."""
    user_id = get_jwt_identity()
    try:
        period_start = _month_start()
        db = await get_db()
        pipeline = [
            {'$match': {'user_id': user_id, 'ts': {'$gte': period_start}}},
            {'$group': {
                '_id': None,
                'total_cost': {'$sum': '$cost_usd.total'},
                'prompt_tokens': {'$sum': '$prompt_tokens'},
                'completion_tokens': {'$sum': '$completion_tokens'},
                'calls': {'$sum': 1},
            }},
        ]
        agg = await db.usage_events.aggregate(pipeline).to_list(1)
        totals = agg[0] if agg else {'total_cost': 0, 'prompt_tokens': 0, 'completion_tokens': 0, 'calls': 0}
        totals.pop('_id', None)

        # By feature
        feat_pipeline = [
            {'$match': {'user_id': user_id, 'ts': {'$gte': period_start}}},
            {'$group': {
                '_id': '$feature',
                'total_cost': {'$sum': '$cost_usd.total'},
                'calls': {'$sum': 1},
            }},
            {'$sort': {'total_cost': -1}},
        ]
        by_feature = await db.usage_events.aggregate(feat_pipeline).to_list(20)

        from app.utils import make_serializable
        return jsonify({
            'totals': make_serializable(totals),
            'by_feature': make_serializable(by_feature),
            'period_start': period_start.isoformat(),
        }), 200
    except Exception as e:
        logger.error(f"my_usage error: {e}", exc_info=True)
        return jsonify({'error': str(e)}), 500


@usage_bp.route('/focus-groups/<fg_id>', methods=['GET'])
@jwt_required()
async def focus_group_usage(fg_id: str):
    """GET /api/usage/focus-groups/<id> — usage for a specific focus group (owner or admin)."""
    user_id = get_jwt_identity()
    try:
        # Auth check — owner or admin
        db = await get_db()
        from bson import ObjectId
        try:
            fg = await db.focus_groups.find_one({'_id': ObjectId(fg_id)})
        except Exception:
            return jsonify({'error': 'Invalid id'}), 400
        if not fg:
            return jsonify({'error': 'Not found'}), 404

        from app.models.user import User
        user = await User.find_by_id(user_id)
        is_admin = user and user.get('role') == 'admin'
        is_owner = fg.get('created_by') == user_id or str(fg.get('user_id', '')) == user_id
        if not is_admin and not is_owner:
            return jsonify({'error': 'Forbidden'}), 403

        pipeline = [
            {'$match': {'focus_group_id': fg_id}},
            {'$group': {
                '_id': None,
                'total_cost': {'$sum': '$cost_usd.total'},
                'prompt_tokens': {'$sum': '$prompt_tokens'},
                'completion_tokens': {'$sum': '$completion_tokens'},
                'calls': {'$sum': 1},
            }},
        ]
        agg = await db.usage_events.aggregate(pipeline).to_list(1)
        totals = agg[0] if agg else {'total_cost': 0, 'prompt_tokens': 0, 'completion_tokens': 0, 'calls': 0}
        totals.pop('_id', None)

        from app.utils import make_serializable
        return jsonify({'totals': make_serializable(totals), 'focus_group_id': fg_id}), 200
    except Exception as e:
        logger.error(f"focus_group_usage error: {e}", exc_info=True)
        return jsonify({'error': str(e)}), 500