"""
Application settings and configuration
"""
from functools import lru_cache
from typing import List, Optional

from pydantic import Field, validator
from pydantic_settings import BaseSettings


class Settings(BaseSettings):
    """Application settings"""
    
    # Basic Configuration
    SERVICE_NAME: str = "user-management"
    DEBUG: bool = False
    ENVIRONMENT: str = "development"
    LOG_LEVEL: str = "INFO"
    
    # API Configuration
    API_V1_PREFIX: str = "/api/v1"
    HOST: str = "0.0.0.0"
    PORT: int = 8005
    
    # Security
    SECRET_KEY: str = Field(..., min_length=32)
    JWT_SECRET_KEY: str = Field(..., min_length=32)
    JWT_ALGORITHM: str = "HS256"
    JWT_ACCESS_TOKEN_EXPIRE_MINUTES: int = 30
    JWT_REFRESH_TOKEN_EXPIRE_DAYS: int = 7
    PASSWORD_MIN_LENGTH: int = 8
    
    # CORS
    ALLOWED_ORIGINS: List[str] = ["*"]
    
    # Database
    MONGODB_URL: str = Field(..., description="MongoDB connection URL")
    MONGODB_DB_NAME: str = "sentinel_users"
    REDIS_URL: str = Field(..., description="Redis connection URL")
    
    # Rate Limiting
    RATE_LIMIT_REQUESTS: int = 100
    RATE_LIMIT_WINDOW: int = 60  # seconds
    
    # Email Configuration
    EMAIL_SMTP_HOST: Optional[str] = None
    EMAIL_SMTP_PORT: int = 587
    EMAIL_SMTP_USER: Optional[str] = None
    EMAIL_SMTP_PASSWORD: Optional[str] = None
    EMAIL_FROM_ADDRESS: Optional[str] = None
    EMAIL_FROM_NAME: str = "Sentinel"
    
    # External Services
    GOOGLE_CLIENT_ID: Optional[str] = None
    GOOGLE_CLIENT_SECRET: Optional[str] = None
    GITHUB_CLIENT_ID: Optional[str] = None
    GITHUB_CLIENT_SECRET: Optional[str] = None
    
    # Feature Flags
    ENABLE_REGISTRATION: bool = True
    ENABLE_EMAIL_VERIFICATION: bool = True
    ENABLE_PASSWORD_RESET: bool = True
    ENABLE_TWO_FACTOR_AUTH: bool = False
    ENABLE_OAUTH: bool = False
    
    @validator("ALLOWED_ORIGINS", pre=True)
    def assemble_cors_origins(cls, v):
        if isinstance(v, str) and not v.startswith("["):
            return [i.strip() for i in v.split(",")]
        elif isinstance(v, (list, str)):
            return v
        raise ValueError(v)
    
    class Config:
        env_file = ".env"
        case_sensitive = True


@lru_cache()
def get_settings() -> Settings:
    """Get cached settings instance"""
    return Settings()