import os
import logging
from typing import Optional
from dotenv import load_dotenv

# Load environment variables from local .env if present
env_path = os.path.join(os.path.dirname(os.path.dirname(os.path.abspath(__file__))), ".env")
if os.path.exists(env_path):
    load_dotenv(dotenv_path=env_path)

os.environ["GRADIO_ANALYTICS_ENABLED"] = "False"

# Logging configuration
LOG_LEVEL = os.getenv("LOG_LEVEL", "INFO").upper()
logging.basicConfig(
    level=getattr(logging, LOG_LEVEL, logging.INFO),
    format="%(asctime)s [%(levelname)s] %(name)s: %(message)s",
    datefmt="%Y-%m-%d %H:%M:%S",
)
logger = logging.getLogger("document_intelligence")


class Settings:
    """Application configuration loaded from environment variables."""

    NVIDIA_API_KEY: Optional[str] = os.getenv("NVIDIA_API_KEY")
    NVIDIA_BASE_URL: str = os.getenv(
        "NVIDIA_BASE_URL", "https://integrate.api.nvidia.com/v1"
    )
    NVIDIA_MODEL: str = os.getenv(
        "NVIDIA_MODEL", "nvidia/nemotron-3-nano-omni-30b-a3b-reasoning"
    )

    MAX_IMAGE_SIZE_MB: float = float(os.getenv("MAX_IMAGE_SIZE_MB", "10.0"))
    MAX_IMAGE_DIMENSION: int = int(os.getenv("MAX_IMAGE_DIMENSION", "4096"))
    OCR_ENGINE: str = os.getenv("OCR_ENGINE", "auto").lower()

    HOST: str = os.getenv("HOST", "0.0.0.0")
    PORT: int = int(os.getenv("PORT", "8000"))
    BACKEND_URL: str = os.getenv("BACKEND_URL", "http://localhost:8000")

    @classmethod
    def validate(cls) -> None:
        """Validate critical configuration settings without exposing sensitive values."""
        if not cls.NVIDIA_API_KEY:
            logger.warning(
                "NVIDIA_API_KEY is not set. Requests to LLM document intelligence will fail until configured."
            )
        else:
            logger.info("NVIDIA_API_KEY is configured (length: %d chars)", len(cls.NVIDIA_API_KEY))
        logger.info("Using NVIDIA Model: %s", cls.NVIDIA_MODEL)
        logger.info("NVIDIA Base URL: %s", cls.NVIDIA_BASE_URL)
        logger.info("Max Image Size: %.1f MB", cls.MAX_IMAGE_SIZE_MB)


settings = Settings()