import os
import json
import logging

class ConfigLoader:
    """配置加载器，用于加载和管理应用配置"""
    
    _instance = None
    
    @classmethod
    def get_instance(cls):
        """获取单例实例"""
        if cls._instance is None:
            cls._instance = ConfigLoader()
        return cls._instance
    
    def __init__(self):
        """初始化配置加载器"""
        self.config = {}
        self.config_file = os.path.join('config', 'app_config.json')
        
        # 创建配置目录（如果不存在）
        os.makedirs('config', exist_ok=True)
        
        # 加载配置
        self.load_config()
    
    def load_config(self):
        """加载配置文件"""
        try:
            if os.path.exists(self.config_file):
                with open(self.config_file, 'r', encoding='utf-8') as f:
                    self.config = json.load(f)
                logging.info(f"已加载配置文件: {self.config_file}")
            else:
                # 创建默认配置
                self.config = {
                    "app": {
                        "name": "腾智微丝产线包装系统",
                        "version": "1.0.0",
                        "features": {
                            "enable_serial_ports": False,
                            "enable_keyboard_listener": False
                        }
                    },
                    "database": {
                        "type": "sqlite",
                        "path": "db/jtDB.db",
                        "host": "",
                        "port": "",
                        "user": "",
                        "password": "",
                        "name": ""
                    }
                }
                
                # 保存默认配置
                self.save_config()
                logging.info(f"已创建默认配置文件: {self.config_file}")
        except Exception as e:
            logging.error(f"加载配置文件失败: {e}")
            # 使用默认配置
            self.config = {
                "app": {
                    "name": "腾智微丝产线包装系统",
                    "version": "1.0.0",
                    "features": {
                        "enable_serial_ports": False,
                        "enable_keyboard_listener": False
                    }
                }
            }
    
    def save_config(self):
        """保存配置到文件"""
        try:
            with open(self.config_file, 'w', encoding='utf-8') as f:
                json.dump(self.config, f, indent=4, ensure_ascii=False)
            logging.info(f"已保存配置文件: {self.config_file}")
            return True
        except Exception as e:
            logging.error(f"保存配置文件失败: {e}")
            return False
    
    def get_value(self, key_path, default=None):
        """
        获取配置值
        
        Args:
            key_path: 配置键路径，例如 "app.features.enable_serial_ports"
            default: 默认值，如果配置项不存在则返回此值
            
        Returns:
            配置值或默认值
        """
        keys = key_path.split('.')
        value = self.config
        
        try:
            for key in keys:
                value = value[key]
            return value
        except (KeyError, TypeError):
            return default
    
    def set_value(self, key_path, value):
        """
        设置配置值
        
        Args:
            key_path: 配置键路径，例如 "app.features.enable_serial_ports"
            value: 要设置的值
            
        Returns:
            bool: 是否设置成功
        """
        keys = key_path.split('.')
        config = self.config
        
        # 遍历路径中的所有键，除了最后一个
        for key in keys[:-1]:
            if key not in config:
                config[key] = {}
            config = config[key]
        
        # 设置最后一个键的值
        config[keys[-1]] = value
        
        # 保存配置
        return self.save_config()
        
    def get_config(self, key):
        """
        获取serial配置下的指定配置
        
        Args:
            key: 配置键，例如'mdz', 'cz'等
            
        Returns:
            dict: 配置值，未找到则返回None
        """
        if 'serial' not in self.config:
            self.config['serial'] = {}
            
        if key not in self.config['serial']:
            return None
            
        return self.config['serial'][key]
        
    def set_config(self, key, config_data):
        """
        设置serial配置下的指定配置
        
        Args:
            key: 配置键，例如'mdz', 'cz'等
            config_data: 要设置的配置数据
            
        Returns:
            bool: 是否设置成功
        """
        if 'serial' not in self.config:
            self.config['serial'] = {}
            
        self.config['serial'][key] = config_data
        # 这里不保存配置，等待调用save_config方法时一并保存
        return True