from flask import request
from models import db, User, Transaction, ApiCall
from sqlalchemy import desc

class UserService:
    @staticmethod
    def get_profile(user_id):
        user = User.query.get(user_id)
        if not user:
            return {'error': '用户不存在'}, 404
        return user.to_dict(), 200

    @staticmethod
    def update_profile(user_id, data):
        user = User.query.get(user_id)
        if not user:
            return {'error': '用户不存在'}, 404
        
        if 'username' in data:
            user.username = data['username'].strip()
        
        try:
            db.session.commit()
            return {
                'message': '资料更新成功',
                'user': user.to_dict()
            }, 200
        except Exception as e:
            db.session.rollback()
            return {'error': '资料更新失败'}, 500

    @staticmethod
    def get_balance(user_id):
        user = User.query.get(user_id)
        if not user:
            return {'error': '用户不存在'}, 404
        
        return {
            'balance': user.balance,
            'user_id': user.id
        }, 200

    @staticmethod
    def get_transactions(user_id, page, per_page):
        pagination = Transaction.query.filter_by(user_id=user_id)\
            .order_by(desc(Transaction.created_at))\
            .paginate(page=page, per_page=per_page, error_out=False)
        
        return {
            'transactions': [t.to_dict() for t in pagination.items],
            'total': pagination.total,
            'page': page,
            'per_page': per_page,
            'pages': pagination.pages
        }, 200

    @staticmethod
    def get_api_calls(user_id, page, per_page):
        pagination = ApiCall.query.filter_by(user_id=user_id)\
            .order_by(desc(ApiCall.created_at))\
            .paginate(page=page, per_page=per_page, error_out=False)
        
        return {
            'api_calls': [call.to_dict() for call in pagination.items],
            'total': pagination.total,
            'page': page,
            'per_page': per_page,
            'pages': pagination.pages
        }, 200

    @staticmethod
    def get_stats(user_id):
        total_calls = ApiCall.query.filter_by(user_id=user_id).count()
        success_calls = ApiCall.query.filter_by(user_id=user_id, status='success').count()
        failed_calls = ApiCall.query.filter_by(user_id=user_id, status='failed').count()
        
        total_cost = db.session.query(db.func.sum(Transaction.amount))\
            .filter_by(user_id=user_id, type='consume').scalar() or 0
        
        total_recharge = db.session.query(db.func.sum(Transaction.amount))\
            .filter_by(user_id=user_id, type='recharge').scalar() or 0
        
        return {
            'total_calls': total_calls,
            'success_calls': success_calls,
            'failed_calls': failed_calls,
            'total_cost': abs(total_cost),
            'total_recharge': total_recharge
        }, 200