import json
from pathlib import Path
from typing import List
from models.game_data import GameData
from core.db.database import Database

class DataLoader:
    """数据加载器，负责加载游戏数据并提供按属性访问的能力"""
    
    def __init__(self):
        """初始化数据加载器，只在首次创建时加载数据"""
        self._data_cache: List[GameData] = []
        self._db = Database()
        self._load_data()
    
    @property
    def all_data(self) -> List[GameData]:
        """获取所有游戏数据"""
        return self._data_cache
    
    @property
    def flag1_data(self) -> List[GameData]:
        """获取所有包含flag=1的解决方案的游戏数据"""
        return [
            game for game in self._data_cache 
            if any(solution.flag == 1 for solution in game.solutions)
        ]
    
    @property
    def flag2_data(self) -> List[GameData]:
        """获取所有包含flag=2的解决方案的游戏数据"""
        return [
            game for game in self._data_cache 
            if any(solution.flag == 2 for solution in game.solutions)
        ]
    
    def get_data_by_flag(self, flag: int) -> List[GameData]:
        """根据指定的flag获取游戏数据
        
        Args:
            flag: 解决方案的标志值
            
        Returns:
            包含指定flag解决方案的游戏数据列表
        """
        return [
            game for game in self._data_cache 
            if any(solution.flag == flag for solution in game.solutions)
        ]
    
    def _load_data(self):
        """加载游戏数据，仅在初始化时调用一次"""
        try:
            # 首先尝试从数据库加载数据
            if self._db.has_game_data():
                # 从数据库加载数据
                db_data = self._db.get_all_game_data()
                self._data_cache = [self._convert_db_to_dto(item) for item in db_data]
                print(f"从数据库成功加载 {len(self._data_cache)} 条游戏数据")
                return
            
            # 如果数据库中没有数据，则从JSON文件导入
            data_path = Path(__file__).parent.parent.parent / 'data' / '24game_data.json'
            if not data_path.exists():
                raise FileNotFoundError(f"数据文件未找到: {data_path}")

            # 导入数据到数据库
            self._db.import_json_data(data_path)
            
            # 从数据库加载数据
            db_data = self._db.get_all_game_data()
            self._data_cache = [self._convert_db_to_dto(item) for item in db_data]
            print(f"从JSON导入并加载 {len(self._data_cache)} 条游戏数据")

        except json.JSONDecodeError as e:
            raise ValueError(f"JSON解析错误: {e}") from e
        except Exception as e:
            raise RuntimeError(f"数据加载失败: {e}") from e
            
    def _convert_db_to_dto(self, db_item: dict) -> GameData:
        """将数据库记录转换为DTO对象
        
        Args:
            db_item: 数据库记录
            
        Returns:
            转换后的DTO对象
        """
        # 创建DTO对象
        dto_dict = {
            'id': db_item['id'],
            'n1': db_item['num1'],
            'n2': db_item['num2'],
            'n3': db_item['num3'],
            'n4': db_item['num4'],
            's': []
        }
        
        # 添加解法
        for solution in db_item['solutions']:
            dto_dict['s'].append({
                'c': solution['expression'],
                'f': solution['flag']
            })
            
        return GameData.from_dict(dto_dict)