// Browser API and extension-origin facts shared by module contexts.
// Content scripts intentionally keep their callback-style `chrome` calls.
// SPDX-License-Identifier: GPL-3.0-or-later

export function selectExtensionApi(scope = globalThis) {
  return scope.browser ?? scope.chrome ?? null;
}

export const extensionApi = selectExtensionApi();

export function extensionProtocol(api = extensionApi) {
  const url = api?.runtime?.getURL?.("");
  if (typeof url !== "string" || url === "") return "";
  try {
    return new URL(url).protocol;
  } catch {
    return "";
  }
}

export function browserKind(api = extensionApi) {
  return extensionProtocol(api) === "moz-extension:" ? "firefox" : "chrome";
}

export const BROWSER_KIND = browserKind();
export const IS_FIREFOX = BROWSER_KIND === "firefox";

export function extensionDocumentUrl(path, api = extensionApi) {
  return api?.runtime?.getURL?.(path) ?? path;
}

export function expectedBackgroundUrl(api = extensionApi) {
  return extensionDocumentUrl(
    browserKind(api) === "firefox" ? "firefox-background.html" : "background.js",
    api,
  );
}

export function isExactExtensionSender(sender, path, api = extensionApi, { tab = null } = {}) {
  if (sender?.id !== api?.runtime?.id || sender?.url !== extensionDocumentUrl(path, api)) return false;
  if (tab === false && sender.tab !== undefined) return false;
  if (tab === true && sender.tab === undefined) return false;
  return true;
}