import datetime
from sqlalchemy import Column, Integer, String, DateTime
from uuid import uuid4

from app.db.base import Base


class File(Base):
    """
    SQLAlchemy model for the file table.
    Stores metadata about uploaded files.
    """

    __tablename__ = "files"

    id = Column(Integer, primary_key=True, index=True)
    filename = Column(String, nullable=False)
    original_filename = Column(String, nullable=False)
    content_type = Column(String, nullable=False)
    file_size = Column(Integer, nullable=False)  # in bytes
    file_path = Column(String, nullable=False, unique=True)
    created_at = Column(DateTime, default=datetime.datetime.utcnow)
    updated_at = Column(
        DateTime, default=datetime.datetime.utcnow, onupdate=datetime.datetime.utcnow
    )

    @staticmethod
    def generate_unique_filename(original_filename: str) -> str:
        """
        Generate a unique filename to prevent collisions and security issues.
        """
        # Extract file extension from the original filename
        if "." in original_filename:
            extension = original_filename.rsplit(".", 1)[1].lower()
            return f"{uuid4().hex}.{extension}"

        # No extension in the original filename
        return f"{uuid4().hex}"