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

def str_to_bool(value):
    """
    Convert a string to a boolean.
    Accepts common truthy/falsey string values.
    Raises ValueError for unrecognized inputs.
    """
    if not isinstance(value, str):
        raise TypeError("Input must be a string.")

    value_lower = value.strip().lower()

    truthy = {"true", "1", "yes", "y", "on"}
    falsey = {"false", "0", "no", "n", "off"}

    if value_lower in truthy:
        return True
    elif value_lower in falsey:
        return False
    else:
        raise ValueError(f"Cannot convert '{value}' to boolean.")

class Settings(BaseModel):
    DATABASE_URL: str = os.getenv("DATABASE_URL", "postgresql+asyncpg://postgres:postgres@localhost:5432/tasks")
    RABBITMQ_URL: str = os.getenv("RABBITMQ_URL", "amqp://guest:guest@localhost/")
    RABBITMQ_EXCHANGE: str = os.getenv("RABBITMQ_EXCHANGE", "tasks")
    RABBITMQ_EXCHANGE_TYPE: str = "topic"
    MAX_RETRIES: int = int(os.getenv("MAX_RETRIES", "3"))
    DNS_TIMEOUT: float = float(os.getenv("DNS_TIMEOUT", "3.0"))
    DNS_LIFETIME: float = float(os.getenv("DNS_LIFETIME", "5.0"))
    SMTP_TIMEOUT: float = float(os.getenv("SMTP_TIMEOUT", "10.0"))
    HTTP_TIMEOUT: float = float(os.getenv("HTTP_TIMEOUT", "8.0"))

    smtp_host: str = os.getenv("SMTP_HOST", "localhost")
    smtp_port: int = os.getenv("SMTP_PORT", "587")
    smtp_user: Optional[str] = os.getenv("SMTP_USER")
    smtp_password: Optional[str] = os.getenv("SMTP_PASSWORD")
    smtp_starttls: bool = str_to_bool(os.getenv("SMTP_STARTTLS", "true"))
    smtp_sender_fallback: str = os.getenv("SMTP_SENDER", "noreply@example.com")

settings = Settings()