"""SQLite数据库操作模块 - 使用标准库sqlite3"""
import sqlite3
import json
import time
import logging
from typing import Optional, Dict, Any, List
from pathlib import Path
from config import DATABASE_PATH

logger = logging.getLogger(__name__)


class Database:
    """数据库管理类"""
    
    def __init__(self, db_path: str = DATABASE_PATH):
        """初始化数据库连接
        
        Args:
            db_path: 数据库文件路径
        """
        self.db_path = db_path
        self._conn: Optional[sqlite3.Connection] = None
        self._ensure_db_exists()
        self.init_tables()
    
    def _ensure_db_exists(self):
        """确保数据库目录存在"""
        db_dir = Path(self.db_path).parent
        db_dir.mkdir(parents=True, exist_ok=True)
    
    @property
    def conn(self) -> sqlite3.Connection:
        """获取数据库连接（懒加载）"""
        if self._conn is None:
            try:
                self._conn = sqlite3.connect(
                    self.db_path,
                    check_same_thread=False,  # 允许多线程访问
                    isolation_level=None,  # 自动提交
                    timeout=30.0  # 增加超时时间
                )
                self._conn.row_factory = sqlite3.Row  # 支持字典式访问
                
                # 启用WAL模式以提高并发性能
                self._conn.execute("PRAGMA journal_mode=WAL")
                self._conn.execute("PRAGMA synchronous=NORMAL")
                self._conn.execute("PRAGMA cache_size=1000")
                self._conn.execute("PRAGMA temp_store=MEMORY")
                
                logger.info(f"数据库连接成功: {self.db_path}")
            except Exception as e:
                logger.error(f"数据库连接失败: {e}", exc_info=True)
                raise
        return self._conn
    
    def init_tables(self):
        """初始化数据库表"""
        cursor = self.conn.cursor()
        
        # 用户表
        cursor.execute("""
            CREATE TABLE IF NOT EXISTS users (
                user_id INTEGER PRIMARY KEY,
                username TEXT,
                created_at INTEGER NOT NULL,
                last_active INTEGER NOT NULL
            )
        """)
        
        # 游戏状态表
        cursor.execute("""
            CREATE TABLE IF NOT EXISTS game_states (
                id INTEGER PRIMARY KEY AUTOINCREMENT,
                chat_id INTEGER NOT NULL,
                user_id INTEGER NOT NULL,
                game_type TEXT NOT NULL,
                state_data TEXT,
                created_at INTEGER NOT NULL,
                updated_at INTEGER NOT NULL,
                UNIQUE(chat_id, user_id, game_type)
            )
        """)
        
        # 创建索引
        cursor.execute("""
            CREATE INDEX IF NOT EXISTS idx_chat_user 
            ON game_states(chat_id, user_id)
        """)
        
        # 游戏统计表
        cursor.execute("""
            CREATE TABLE IF NOT EXISTS game_stats (
                id INTEGER PRIMARY KEY AUTOINCREMENT,
                user_id INTEGER NOT NULL,
                game_type TEXT NOT NULL,
                wins INTEGER DEFAULT 0,
                losses INTEGER DEFAULT 0,
                draws INTEGER DEFAULT 0,
                total_plays INTEGER DEFAULT 0,
                UNIQUE(user_id, game_type)
            )
        """)
        
        # 用户积分表 - 简化版本，只保留必要字段
        cursor.execute("""
            CREATE TABLE IF NOT EXISTS user_points (
                user_id INTEGER PRIMARY KEY,
                points INTEGER DEFAULT 0,
                last_checkin_date TEXT,
                created_at INTEGER NOT NULL,
                updated_at INTEGER NOT NULL,
                FOREIGN KEY (user_id) REFERENCES users (user_id)
            )
        """)
        
        logger.info("数据库表初始化完成")
    
    # ===== 用户相关操作 =====
    
    def get_or_create_user(self, user_id: int, username: str = None) -> Dict:
        """获取或创建用户
        
        Args:
            user_id: 用户ID
            username: 用户名
            
        Returns:
            用户信息字典
        """
        cursor = self.conn.cursor()
        current_time = int(time.time())
        
        # 尝试获取用户
        cursor.execute(
            "SELECT * FROM users WHERE user_id = ?",
            (user_id,)
        )
        user = cursor.fetchone()
        
        if user:
            # 更新最后活跃时间
            cursor.execute(
                "UPDATE users SET last_active = ? WHERE user_id = ?",
                (current_time, user_id)
            )
            return dict(user)
        else:
            # 创建新用户
            cursor.execute(
                "INSERT INTO users (user_id, username, created_at, last_active) VALUES (?, ?, ?, ?)",
                (user_id, username, current_time, current_time)
            )
            return {
                'user_id': user_id,
                'username': username,
                'created_at': current_time,
                'last_active': current_time
            }
    
    # ===== 游戏状态相关操作 =====
    
    def get_game_state(self, chat_id: int, user_id: int, game_type: str) -> Optional[Dict]:
        """获取游戏状态
        
        Args:
            chat_id: 会话ID
            user_id: 用户ID
            game_type: 游戏类型
            
        Returns:
            游戏状态字典，如果不存在返回None
        """
        cursor = self.conn.cursor()
        cursor.execute(
            "SELECT * FROM game_states WHERE chat_id = ? AND user_id = ? AND game_type = ?",
            (chat_id, user_id, game_type)
        )
        row = cursor.fetchone()
        
        if row:
            state = dict(row)
            # 解析JSON数据
            if state.get('state_data'):
                state['state_data'] = json.loads(state['state_data'])
            return state
        return None
    
    def save_game_state(self, chat_id: int, user_id: int, game_type: str, state_data: Dict):
        """保存游戏状态
        
        Args:
            chat_id: 会话ID
            user_id: 用户ID
            game_type: 游戏类型
            state_data: 状态数据字典
        """
        cursor = self.conn.cursor()
        current_time = int(time.time())
        state_json = json.dumps(state_data, ensure_ascii=False)
        
        cursor.execute("""
            INSERT INTO game_states (chat_id, user_id, game_type, state_data, created_at, updated_at)
            VALUES (?, ?, ?, ?, ?, ?)
            ON CONFLICT(chat_id, user_id, game_type) 
            DO UPDATE SET state_data = ?, updated_at = ?
        """, (chat_id, user_id, game_type, state_json, current_time, current_time, 
              state_json, current_time))
        
        logger.debug(f"保存游戏状态: chat_id={chat_id}, user_id={user_id}, game_type={game_type}")
    
    def delete_game_state(self, chat_id: int, user_id: int, game_type: str):
        """删除游戏状态
        
        Args:
            chat_id: 会话ID
            user_id: 用户ID
            game_type: 游戏类型
        """
        cursor = self.conn.cursor()
        cursor.execute(
            "DELETE FROM game_states WHERE chat_id = ? AND user_id = ? AND game_type = ?",
            (chat_id, user_id, game_type)
        )
        logger.debug(f"删除游戏状态: chat_id={chat_id}, user_id={user_id}, game_type={game_type}")
    
    def cleanup_old_sessions(self, timeout: int = 1800):
        """清理过期的游戏会话
        
        Args:
            timeout: 超时时间（秒）
        """
        cursor = self.conn.cursor()
        cutoff_time = int(time.time()) - timeout
        
        cursor.execute(
            "DELETE FROM game_states WHERE updated_at < ?",
            (cutoff_time,)
        )
        deleted = cursor.rowcount
        
        if deleted > 0:
            logger.info(f"清理了 {deleted} 个过期游戏会话")
    
    # ===== 游戏统计相关操作 =====
    
    def get_game_stats(self, user_id: int, game_type: str) -> Dict:
        """获取游戏统计
        
        Args:
            user_id: 用户ID
            game_type: 游戏类型
            
        Returns:
            统计数据字典
        """
        cursor = self.conn.cursor()
        cursor.execute(
            "SELECT * FROM game_stats WHERE user_id = ? AND game_type = ?",
            (user_id, game_type)
        )
        row = cursor.fetchone()
        
        if row:
            return dict(row)
        else:
            # 返回默认值
            return {
                'user_id': user_id,
                'game_type': game_type,
                'wins': 0,
                'losses': 0,
                'draws': 0,
                'total_plays': 0
            }
    
    def update_game_stats(self, user_id: int, game_type: str, 
                         win: bool = False, loss: bool = False, draw: bool = False):
        """更新游戏统计
        
        Args:
            user_id: 用户ID
            game_type: 游戏类型
            win: 是否获胜
            loss: 是否失败
            draw: 是否平局
        """
        cursor = self.conn.cursor()
        
        # 使用UPSERT语法
        cursor.execute("""
            INSERT INTO game_stats (user_id, game_type, wins, losses, draws, total_plays)
            VALUES (?, ?, ?, ?, ?, 1)
            ON CONFLICT(user_id, game_type)
            DO UPDATE SET 
                wins = wins + ?,
                losses = losses + ?,
                draws = draws + ?,
                total_plays = total_plays + 1
        """, (user_id, game_type, int(win), int(loss), int(draw),
              int(win), int(loss), int(draw)))
        
        logger.debug(f"更新游戏统计: user_id={user_id}, game_type={game_type}")
    
    # ===== 积分相关操作 =====
    
    def get_user_points(self, user_id: int) -> Dict:
        """获取用户积分信息
        
        Args:
            user_id: 用户ID
            
        Returns:
            积分信息字典
        """
        cursor = self.conn.cursor()
        cursor.execute(
            "SELECT * FROM user_points WHERE user_id = ?",
            (user_id,)
        )
        row = cursor.fetchone()
        
        if row:
            return dict(row)
        else:
            # 创建新用户积分记录
            current_time = int(time.time())
            cursor.execute(
                "INSERT INTO user_points (user_id, points, created_at, updated_at) VALUES (?, 0, ?, ?)",
                (user_id, current_time, current_time)
            )
            return {
                'user_id': user_id,
                'points': 0,
                'last_checkin_date': None,
                'created_at': current_time,
                'updated_at': current_time
            }
    
    def add_points(self, user_id: int, points: int, source: str, description: str = None) -> bool:
        """添加积分
        
        Args:
            user_id: 用户ID
            points: 积分数量
            source: 积分来源
            description: 描述
            
        Returns:
            是否成功
        """
        if points <= 0:
            logger.warning(f"积分数量无效: {points}")
            return False
            
        cursor = self.conn.cursor()
        current_time = int(time.time())
        
        try:
            # 确保用户存在
            self.get_or_create_user(user_id)
            
            # 更新用户积分
            cursor.execute("""
                INSERT OR REPLACE INTO user_points (user_id, points, created_at, updated_at)
                VALUES (?, COALESCE((SELECT points FROM user_points WHERE user_id = ?), 0) + ?, ?, ?)
            """, (user_id, user_id, points, current_time, current_time))
            
            logger.info(f"用户 {user_id} 成功获得 {points} 积分，来源：{source}")
            return True
            
        except Exception as e:
            logger.error(f"添加积分失败: user_id={user_id}, points={points}, error={e}", exc_info=True)
            return False
    
    def consume_points(self, user_id: int, points: int, source: str, description: str = None) -> bool:
        """消费积分
        
        Args:
            user_id: 用户ID
            points: 积分数量
            source: 消费来源
            description: 描述
            
        Returns:
            是否成功
        """
        if points <= 0:
            return False
            
        cursor = self.conn.cursor()
        current_time = int(time.time())
        
        try:
            # 检查积分是否足够
            cursor.execute(
                "SELECT points FROM user_points WHERE user_id = ?",
                (user_id,)
            )
            row = cursor.fetchone()
            
            if not row or row[0] < points:
                logger.warning(f"用户 {user_id} 积分不足，需要 {points}，当前可用 {row[0] if row else 0}")
                return False
            
            # 消费积分
            cursor.execute(
                "UPDATE user_points SET points = points - ?, updated_at = ? WHERE user_id = ?",
                (points, current_time, user_id)
            )
            
            logger.debug(f"用户 {user_id} 消费 {points} 积分，来源：{source}")
            return True
            
        except Exception as e:
            logger.error(f"消费积分失败: {e}")
            return False
    
    def check_daily_checkin(self, user_id: int, date: str) -> bool:
        """检查用户是否已签到
        
        Args:
            user_id: 用户ID
            date: 日期字符串 (YYYY-MM-DD)
            
        Returns:
            是否已签到
        """
        cursor = self.conn.cursor()
        cursor.execute(
            "SELECT last_checkin_date FROM user_points WHERE user_id = ?",
            (user_id,)
        )
        row = cursor.fetchone()
        return row and row[0] == date
    
    def daily_checkin(self, user_id: int, points: int) -> bool:
        """每日签到
        
        Args:
            user_id: 用户ID
            points: 签到积分
            
        Returns:
            是否成功
        """
        from datetime import datetime
        today = datetime.now().strftime('%Y-%m-%d')
        
        if self.check_daily_checkin(user_id, today):
            logger.warning(f"用户 {user_id} 今日已签到")
            return False
        
        cursor = self.conn.cursor()
        current_time = int(time.time())
        
        try:
            # 确保用户存在
            self.get_or_create_user(user_id)
            
            # 获取签到前积分
            points_before = self.get_user_points(user_id)
            logger.info(f"用户 {user_id} 签到前积分: {points_before['points']}")
            
            # 更新积分和签到日期
            cursor.execute("""
                INSERT OR REPLACE INTO user_points (user_id, points, last_checkin_date, created_at, updated_at)
                VALUES (?, COALESCE((SELECT points FROM user_points WHERE user_id = ?), 0) + ?, ?, ?, ?)
            """, (user_id, user_id, points, today, current_time, current_time))
            
            # 验证积分是否真的增加了
            points_after = self.get_user_points(user_id)
            logger.info(f"用户 {user_id} 签到后积分: {points_after['points']}")
            
            if points_after['points'] > points_before['points']:
                logger.info(f"用户 {user_id} 签到成功，积分增加: {points_after['points'] - points_before['points']}")
                return True
            else:
                logger.error(f"用户 {user_id} 签到失败，积分未增加")
                return False
            
        except Exception as e:
            logger.error(f"每日签到失败: {e}", exc_info=True)
            return False
    
    def get_points_leaderboard(self, limit: int = 10) -> List[Dict]:
        """获取积分排行榜
        
        Args:
            limit: 限制数量
            
        Returns:
            排行榜列表
        """
        cursor = self.conn.cursor()
        cursor.execute("""
            SELECT u.user_id, u.username, up.points
            FROM users u
            LEFT JOIN user_points up ON u.user_id = up.user_id
            ORDER BY COALESCE(up.points, 0) DESC
            LIMIT ?
        """, (limit,))
        rows = cursor.fetchall()
        return [dict(row) for row in rows]
    
    def close(self):
        """关闭数据库连接"""
        if self._conn:
            self._conn.close()
            self._conn = None
            logger.info("数据库连接已关闭")


# 全局数据库实例
_db_instance: Optional[Database] = None


def get_db() -> Database:
    """获取全局数据库实例（单例模式）"""
    global _db_instance
    if _db_instance is None:
        _db_instance = Database()
    return _db_instance