"""SQLite数据库操作模块 - 使用标准库sqlite3"""
import sqlite3
import json
import time
from typing import *
from Convention.Runtime.GlobalConfig import ProjectConfig, ConsoleFrontColor
from Convention.Runtime.Architecture import Architecture
from Convention.Runtime.File import ToolFile

config = ProjectConfig()
DATABASE_PATH = config.GetFile(config.FindItem("database_path", "db.db"), False).GetFullPath()

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()
        Architecture.Register(Database, self, lambda: None)
    
    def _ensure_db_exists(self):
        """确保数据库目录存在"""
        db_dir = ToolFile(self.db_path).BackToParentDir()
        db_dir.MustExistsPath()
    
    @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")
                
                config.Log("Info", f"{ConsoleFrontColor.GREEN}数据库连接成功: {self.db_path}{ConsoleFrontColor.RESET}")
            except Exception as e:
                config.Log("Error", f"{ConsoleFrontColor.RED}数据库连接失败: {e}{ConsoleFrontColor.RESET}", exc_info=True)
                raise
        return self._conn
    
    def _table_exists(self, table_name: str) -> bool:
        """检查表是否存在
        
        Args:
            table_name: 表名
            
        Returns:
            是否存在
        """
        cursor = self.conn.cursor()
        cursor.execute("SELECT name FROM sqlite_master WHERE type='table' AND name=?", (table_name,))
        return cursor.fetchone() is not None

    def define_table(self, table_name: str):
        """定义表
        
        Args:
            table_name: 表名
        """
        if not self._table_exists(table_name):
            cursor = self.conn.cursor()
            cursor.execute(f"CREATE TABLE IF NOT EXISTS {table_name} (id INTEGER PRIMARY KEY AUTOINCREMENT)")
            config.Log("Info", f"{ConsoleFrontColor.GREEN}为表 {table_name} 创建{ConsoleFrontColor.RESET}")
        return self

    def _column_exists(self, table_name: str, column_name: str) -> bool:
        """检查表中列是否存在
        
        Args:
            table_name: 表名
            column_name: 列名
            
        Returns:
            是否存在
        """
        cursor = self.conn.cursor()
        cursor.execute(f"PRAGMA table_info({table_name})")
        columns = [row[1] for row in cursor.fetchall()]
        return column_name in columns
    
    def _add_column_if_not_exists(self, table_name: str, column_name: str, column_def: str):
        """安全地添加列（如果不存在）
        
        Args:
            table_name: 表名
            column_name: 列名
            column_def: 列定义（如 "INTEGER" 或 "TEXT DEFAULT ''"）
        """
        if not self._column_exists(table_name, column_name):
            try:
                cursor = self.conn.cursor()
                cursor.execute(f"ALTER TABLE {table_name} ADD COLUMN {column_name} {column_def}")
                config.Log("Info", f"{ConsoleFrontColor.GREEN}为表 {table_name} 添加列 {column_name}{ConsoleFrontColor.RESET}")
            except Exception as e:
                config.Log("Warning", f"{ConsoleFrontColor.YELLOW}添加列失败: {e}{ConsoleFrontColor.RESET}")
    
    def define_column(self, table_name: str, column_name: str, column_def: str):
        """定义列
        
        Args:
            table_name: 表名
            column_name: 列名
            column_def: 列定义（如 "INTEGER" 或 "TEXT DEFAULT ''"）
        """
        self._add_column_if_not_exists(table_name, column_name, column_def)
        return self

    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
            )
        """)
    
    def close(self):
        """关闭数据库连接"""
        if self._conn:
            self._conn.close()
            self._conn = None
            config.Log("Info", f"{ConsoleFrontColor.GREEN}数据库连接已关闭{ConsoleFrontColor.RESET}")

def get_db() -> Database:
    """获取全局数据库实例（单例模式）"""
    if not Architecture.Contains(Database):
        return Database()
    return Architecture.Get(Database)

__all__ = ["get_db"]