"""配置管理模块

提供应用程序配置的加载和管理功能。
支持多环境配置和环境变量覆盖。
"""

import os
from pathlib import Path
from typing import Any, Dict, Optional
import yaml
from pydantic import Field
from pydantic_settings import BaseSettings
from pydantic_settings import SettingsConfigDict


class AppConfig(BaseSettings):
    """应用程序配置"""
    model_config = SettingsConfigDict(
        env_prefix="APP_",
        env_file=".env",
        env_file_encoding="utf-8",
        case_sensitive=False,
        extra="ignore"  # 忽略额外字段
    )
    
    name: str = "音频转文字服务"
    version: str = "1.0.0"
    debug: bool = False
    host: str = "127.0.0.1"
    port: int = 7860
    max_file_size: int = 2147483648  # 2GB
    max_files_count: int = 100
    concurrent_tasks: int = 5


class OSSConfig(BaseSettings):
    """OSS配置"""
    model_config = SettingsConfigDict(
        env_prefix="OSS_",
        env_file=".env",
        env_file_encoding="utf-8",
        case_sensitive=False,
        extra="ignore"
    )
    
    endpoint: str = Field(..., description="OSS服务端点")
    access_key_id: str = Field(..., description="访问密钥ID")
    access_key_secret: str = Field(..., description="访问密钥密码")
    bucket_name: str = Field(..., description="存储桶名称")
    upload_timeout: int = 300
    url_expire_hours: int = 24
    temp_prefix: str = "temp/audio"
    auto_cleanup_days: int = 7


class DashScopeConfig(BaseSettings):
    """阿里云百炼API配置"""
    model_config = SettingsConfigDict(
        env_prefix="DASHSCOPE_",
        env_file=".env",
        env_file_encoding="utf-8",
        case_sensitive=False,
        extra="ignore"
    )
    
    api_key: str = Field(..., description="API密钥")
    base_url: str = "https://dashscope.aliyuncs.com/api/v1"
    model: str = "paraformer-v2"
    timeout: int = 300
    max_retries: int = 3
    retry_delay: int = 5
    language_hints: list[str] = ["zh", "en"]


class TaskConfig(BaseSettings):
    """任务配置"""
    model_config = SettingsConfigDict(
        env_prefix="TASK_",
        env_file=".env",
        env_file_encoding="utf-8",
        case_sensitive=False,
        extra="ignore"
    )
    
    status_check_interval: int = 2
    max_processing_time: int = 3600  # 1小时
    queue_size: int = 1000


class LoggingConfig(BaseSettings):
    """日志配置"""
    model_config = SettingsConfigDict(
        env_prefix="LOGGING_",
        env_file=".env",
        env_file_encoding="utf-8",
        case_sensitive=False,
        extra="ignore"
    )
    
    level: str = "INFO"
    format: str = "structured"
    file_max_size: str = "10MB"
    backup_count: int = 5


class Config:
    """配置管理器"""
    
    def __init__(self, environment: Optional[str] = None):
        """初始化配置管理器
        
        Args:
            environment: 环境名称（development/production）
        """
        self.environment = environment or os.getenv("ENVIRONMENT", "development")
        self._config_data = self._load_config()
        
        # 初始化各个配置模块
        self.app = AppConfig(**self._config_data.get("app", {}))
        
        # OSS配置 - 直接创建实例以支持环境变量覆盖
        self.oss = OSSConfig()
        
        # DashScope配置 - 直接创建实例以支持环境变量覆盖
        self.dashscope = DashScopeConfig()
        
        self.task = TaskConfig(**self._config_data.get("task", {}))
        self.logging = LoggingConfig(**self._config_data.get("logging", {}))
    
    def _load_config(self) -> Dict[str, Any]:
        """加载配置文件"""
        config_dir = Path(__file__).parent.parent.parent / "config" / "environments"
        config_file = config_dir / f"{self.environment}.yaml"
        
        if not config_file.exists():
            raise FileNotFoundError(f"配置文件不存在: {config_file}")
        
        with open(config_file, 'r', encoding='utf-8') as file:
            return yaml.safe_load(file)
    
    def get_project_root(self) -> Path:
        """获取项目根目录"""
        return Path(__file__).parent.parent.parent
    
    def get_logs_dir(self) -> Path:
        """获取日志目录"""
        logs_dir = self.get_project_root() / "logs"
        logs_dir.mkdir(exist_ok=True)
        return logs_dir
    
    def get_temp_dir(self) -> Path:
        """获取临时文件目录"""
        temp_dir = self.get_project_root() / "temp"
        temp_dir.mkdir(exist_ok=True)
        return temp_dir


# 全局配置实例
config = Config()


def get_config() -> Config:
    """获取配置实例"""
    return config


def reload_config(environment: Optional[str] = None) -> Config:
    """重新加载配置"""
    global config
    config = Config(environment)
    return config