// TODO: This file is a temporary solution to fix URL generation issues in Dockerized environments.
// The custom CloneableURL class and getRequestUrl function are workarounds until this Next.js issue is resolved:
// https://github.com/vercel/next.js/issues/54450
// Once it's fixed, consider removing this file and using the standard Next.js URL handling methods.

import getConfig from 'next/config';
import { NextRequest } from 'next/server';

/**
 * A class that extends the native URL class to include a clone method.
 * It allows duplicating the URL instance while preserving all properties.
 */
class CloneableURL extends URL {
	/**
	 * Creates a new CloneableURL instance with the same properties as the current one.
	 * @returns {CloneableURL} A new CloneableURL instance.
	 */
	clone(): CloneableURL {
		return new CloneableURL(this.href); // Creates a clone of the URL using its href
	}
}

/**
 * Generates a full URL using the request headers and the NextRequest object.
 * This ensures the URL is accurately reconstructed in environments where headers might be modified by proxies or load balancers.
 *
 * @param {NextRequest} req - The Next.js server request object.
 * @returns {CloneableURL} - The full URL constructed from either the environment variable or the request headers.
 */
export function getRequestUrl(req: NextRequest): CloneableURL {
	const { publicRuntimeConfig } = getConfig() || {};
	// eslint-disable-next-line turbo/no-undeclared-env-vars
	const BASE_URL = process.env.BASE_URL || publicRuntimeConfig?.BASE_URL || null;

	// Get 'x-forwarded-host' header if available, or fallback to 'host' or req.nextUrl.host
	const hostHeader = req.headers.get('x-forwarded-host') || req.headers.get('host') || req.nextUrl.host;

	// Determine the protocol from 'X-Forwarded-Proto' header or use req.nextUrl.protocol by default
	const protocol = req.headers.get('x-forwarded-proto')
		? `${req.headers.get('x-forwarded-proto')}:`
		: req.nextUrl.protocol;

	// Create baseURL: use BASE_URL if available, otherwise construct it using protocol and hostHeader
	const baseURL = BASE_URL || `${protocol}//${hostHeader}`;

	// Construct the full URL using baseURL, pathname, and search parameters from req.nextUrl
	const fullUrlString = `${baseURL}${req.nextUrl.pathname}${req.nextUrl.search}`;

	// Return a new CloneableURL object
	return new CloneableURL(fullUrlString);
}