from pydantic import BaseModel, Field, validator
from typing import Optional
import os

class OllamaConfig(BaseModel):
    """Ollama配置验证"""
    base_url: str = Field(default="http://localhost:11434")
    model_name: str = Field(default="qwen2.5:latest")
    temperature: float = Field(default=0.7, ge=0.0, le=1.0)
    max_tokens: int = Field(default=2048, gt=0)

class FlaskConfig(BaseModel):
    """Flask配置验证"""
    host: str = Field(default="0.0.0.0")
    port: int = Field(default=5000, gt=0, lt=65536)
    debug: bool = Field(default=False)
    api_prefix: str = Field(default="/api/v1")

class Config(BaseModel):
    """应用配置验证"""
    ollama: OllamaConfig = Field(default_factory=OllamaConfig)
    flask: FlaskConfig = Field(default_factory=FlaskConfig)
    
    @validator('ollama.base_url')
    def validate_base_url(cls, v):
        if not v.startswith(('http://', 'https://')):
            raise ValueError('base_url must start with http:// or https://')
        return v
    
    @validator('flask.api_prefix')
    def validate_api_prefix(cls, v):
        if not v.startswith('/'):
            raise ValueError('api_prefix must start with /')
        return v

def validate_config() -> Config:
    """验证并返回配置"""
    try:
        config = Config(
            ollama=OllamaConfig(
                base_url=os.getenv("OLLAMA_BASE_URL", "http://localhost:11434"),
                model_name=os.getenv("DEFAULT_MODEL", "qwen2.5:latest"),
                temperature=float(os.getenv("TEMPERATURE", "0.7")),
                max_tokens=int(os.getenv("MAX_TOKENS", "2048"))
            ),
            flask=FlaskConfig(
                host=os.getenv("FLASK_HOST", "0.0.0.0"),
                port=int(os.getenv("FLASK_PORT", "5000")),
                debug=os.getenv("FLASK_DEBUG", "False").lower() == "true",
                api_prefix=os.getenv("API_PREFIX", "/api/v1")
            )
        )
        return config
    except Exception as e:
        raise ValueError(f"配置验证失败: {str(e)}")