"""
Application configuration settings.
Handles environment variables and application constants.
"""

import os
import json
from typing import List
from dotenv import load_dotenv

load_dotenv()


class Settings:
    """Application settings loaded from environment variables."""
    
    # Database configuration
    DB_HOST: str = os.getenv("DB_HOST", "localhost")
    DB_PORT: int = int(os.getenv("DB_PORT", "3306"))
    DB_NAME: str = os.getenv("DB_NAME", "aiguide")
    DB_USER: str = os.getenv("DB_USER", "root")
    DB_PASSWORD: str = os.getenv("DB_PASSWORD", "")
    
    @property
    def DATABASE_URL(self) -> str:
        """MySQL database connection URL."""
        return f"mysql+pymysql://{self.DB_USER}:{self.DB_PASSWORD}@{self.DB_HOST}:{self.DB_PORT}/{self.DB_NAME}"
    
    # JWT configuration
    SECRET_KEY: str = os.getenv("SECRET_KEY", "your-secret-key-change-in-production")
    ALGORITHM: str = "HS256"
    ACCESS_TOKEN_EXPIRE_MINUTES: int = int(os.getenv("ACCESS_TOKEN_EXPIRE_MINUTES", "30"))
    
    # CORS configuration
    @property
    def ALLOWED_ORIGINS(self) -> List[str]:
        """Parse allowed origins from environment variable."""
        origins_str = os.getenv("ALLOWED_ORIGINS", '["http://localhost:3000", "https://aiguid.app"]')
        try:
            return json.loads(origins_str)
        except json.JSONDecodeError:
            return ["http://localhost:3000", "https://aiguid.app"]
    
    # Google OAuth configuration
    GOOGLE_CLIENT_ID: str = os.getenv("GOOGLE_CLIENT_ID", "")
    GOOGLE_CLIENT_SECRET: str = os.getenv("GOOGLE_CLIENT_SECRET", "")
    GOOGLE_REDIRECT_URI: str = os.getenv("GOOGLE_REDIRECT_URI", "https://aiguid.app/api/auth/google/callback")
    
    # Sentry configuration
    SENTRY_DSN: str = os.getenv("SENTRY_DSN", "")
    
    # Performance and caching
    CACHE_TTL_MINUTES: int = int(os.getenv("CACHE_TTL_MINUTES", "5"))
    RATE_LIMIT_REQUESTS: int = int(os.getenv("RATE_LIMIT_REQUESTS", "100"))
    RATE_LIMIT_WINDOW: int = int(os.getenv("RATE_LIMIT_WINDOW", "60"))
    
    # Logging
    LOG_LEVEL: str = os.getenv("LOG_LEVEL", "INFO")
    
    # Security
    ENABLE_RATE_LIMITING: bool = os.getenv("ENABLE_RATE_LIMITING", "true").lower() == "true"
    ENABLE_CORS: bool = os.getenv("ENABLE_CORS", "true").lower() == "true"
    ENABLE_HTTPS_REDIRECT: bool = os.getenv("ENABLE_HTTPS_REDIRECT", "true").lower() == "true"
    
    # Application metadata
    APP_NAME: str = os.getenv("APP_NAME", "Aiguid API")
    APP_VERSION: str = os.getenv("APP_VERSION", "1.0.0")


# Global settings instance
settings = Settings()