import { env } from "cloudflare:workers";

const DEV_FORGE_HOST = "localhost";
const DEV_EDITOR_HOST = "editor.localhost";

function configured(): URL | null {
  if (!env.EDITOR_ORIGIN) return null;
  try {
    return new URL(env.EDITOR_ORIGIN);
  } catch {
    return null;
  }
}

/**
 * The editor runs on its own origin so its scripts (VS Code, Open VSX extensions) can never reach forge
 * cookies or pages. Production sets EDITOR_ORIGIN, ideally on a separate registrable domain; local dev maps
 * `localhost:<port>` to `editor.localhost:<port>` (browsers resolve `*.localhost` to loopback, and the
 * forge's host-only cookies are never sent to another host).
 */
export function editorOriginFor(forgeUrl: URL): string | null {
  const explicit = configured();
  if (explicit) return explicit.origin;
  if (forgeUrl.hostname !== DEV_FORGE_HOST) return null;
  const url = new URL(forgeUrl.origin);
  url.hostname = DEV_EDITOR_HOST;
  return url.origin;
}

export function isEditorOrigin(url: URL): boolean {
  const explicit = configured();
  if (explicit) return url.origin === explicit.origin;
  return url.hostname === DEV_EDITOR_HOST;
}

/** The forge origin an editor-origin page talks to and accepts messages from. */
export function forgeOriginFor(editorUrl: URL): string {
  if (configured()) return new URL(env.PUBLIC_URL).origin;
  const url = new URL(editorUrl.origin);
  url.hostname = DEV_FORGE_HOST;
  return url.origin;
}