"""Module to handle the upload process."""

import os
import logging
import re
from flask import Blueprint, request, jsonify, session

upload_bp = Blueprint("upload_bp", __name__)


def sanitize_username(username):
    """Sanitize the username."""
    return re.sub(r"[^a-zA-Z0-9_\-]", "_", username).lower()


@upload_bp.route("/upload/<cdmtype>", methods=["POST"])
def upload(cdmtype):
    """Handle the upload process."""
    try:
        username = session.get("username")
        if not username:
            return jsonify({"message": "False", "error": "No username in session"}), 400

        safe_username = sanitize_username(username)

        # Validate CDM type
        if cdmtype not in ["PR", "WV"]:
            return jsonify({"message": "False", "error": "Invalid CDM type"}), 400

        # Set up user directory paths
        base_path = os.path.join(
            os.getcwd(), "configs", "CDMs", "users_uploaded", safe_username
        )
        pr_path = os.path.join(base_path, "PR")
        wv_path = os.path.join(base_path, "WV")

        # Create necessary directories if they don't exist
        os.makedirs(pr_path, exist_ok=True)
        os.makedirs(wv_path, exist_ok=True)

        # Get uploaded file
        uploaded_file = request.files.get("file")
        if not uploaded_file:
            return jsonify({"message": "False", "error": "No file provided"}), 400

        # Determine correct save path based on cdmtype
        filename = uploaded_file.filename
        assert filename is not None
        target_path = pr_path if cdmtype == "PR" else wv_path
        save_path = os.path.join(target_path, filename)
        uploaded_file.save(save_path)

        return jsonify({"message": "Success", "file_saved_to": save_path})

    except (OSError, IOError, ValueError, AttributeError) as e:
        logging.exception("Upload failed: %s", {e})
        return jsonify({"message": "False", "error": "Server error"}), 500