from pydantic_settings import BaseSettings
from typing import Optional


class PostgreSQLSettings(BaseSettings):
    """PostgreSQL数据库配置"""
    host: str = "localhost"
    port: int = 5432
    user: str = "postgres"
    password: str = "postgres"
    database: str = "book_system"
    min_size: int = 5
    max_size: int = 20
    
    @property
    def url(self) -> str:
        """生成数据库连接URL"""
        return f"postgresql+asyncpg://{self.user}:{self.password}@{self.host}:{self.port}/{self.database}"
    
    class Config:
        env_prefix = "POSTGRES_"


class RedisSettings(BaseSettings):
    """Redis配置"""
    host: str = "localhost"
    port: int = 6379
    password: Optional[str] = None
    db: int = 0
    
    @property
    def url(self) -> str:
        """生成Redis连接URL"""
        if self.password:
            return f"redis://:{self.password}@{self.host}:{self.port}/{self.db}"
        return f"redis://{self.host}:{self.port}/{self.db}"
    
    class Config:
        env_prefix = "REDIS_"


class AppSettings(BaseSettings):
    """应用配置"""
    name: str = "Book System API"
    version: str = "1.0.0"
    debug: bool = False
    secret_key: str = "your-secret-key"
    algorithm: str = "HS256"
    access_token_expire_minutes: int = 30
    
    class Config:
        env_prefix = "APP_"


# 创建设置实例
postgres_settings = PostgreSQLSettings()
redis_settings = RedisSettings()
app_settings = AppSettings()