var ExtensionTestUtils = {};

const { ExtensionTestCommon } = SpecialPowers.Cu.import(
  "resource://testing-common/ExtensionTestCommon.jsm",
  {}
);

ExtensionTestUtils.loadExtension = function(ext) {
  // Cleanup functions need to be registered differently depending on
  // whether we're in browser chrome or plain mochitests.
  var registerCleanup;
  /* global registerCleanupFunction */
  if (typeof registerCleanupFunction != "undefined") {
    registerCleanup = registerCleanupFunction;
  } else {
    registerCleanup = SimpleTest.registerCleanupFunction.bind(SimpleTest);
  }

  var testResolve;
  var testDone = new Promise(resolve => {
    testResolve = resolve;
  });

  var messageHandler = new Map();
  var messageAwaiter = new Map();

  var messageQueue = new Set();

  registerCleanup(() => {
    if (messageQueue.size) {
      let names = Array.from(messageQueue, ([msg]) => msg);
      SimpleTest.is(JSON.stringify(names), "[]", "message queue is empty");
    }
    if (messageAwaiter.size) {
      let names = Array.from(messageAwaiter.keys());
      SimpleTest.is(
        JSON.stringify(names),
        "[]",
        "no tasks awaiting on messages"
      );
    }
  });

  function checkMessages() {
    for (let message of messageQueue) {
      let [msg, ...args] = message;

      let listener = messageAwaiter.get(msg);
      if (listener) {
        messageQueue.delete(message);
        messageAwaiter.delete(msg);

        listener.resolve(...args);
        return;
      }
    }
  }

  function checkDuplicateListeners(msg) {
    if (messageHandler.has(msg) || messageAwaiter.has(msg)) {
      throw new Error("only one message handler allowed");
    }
  }

  function testHandler(kind, pass, msg, ...args) {
    if (kind == "test-eq") {
      let [expected, actual] = args;
      SimpleTest.ok(pass, `${msg} - Expected: ${expected}, Actual: ${actual}`);
    } else if (kind == "test-log") {
      SimpleTest.info(msg);
    } else if (kind == "test-result") {
      SimpleTest.ok(pass, msg);
    }
  }

  var handler = {
    async testResult(kind, pass, msg, ...args) {
      if (kind == "test-done") {
        SimpleTest.ok(pass, msg);
        await testResolve(msg);
      }
      testHandler(kind, pass, msg, ...args);
    },

    testMessage(msg, ...args) {
      var msgHandler = messageHandler.get(msg);
      if (msgHandler) {
        msgHandler(...args);
      } else {
        messageQueue.add([msg, ...args]);
        checkMessages();
      }
    },
  };

  // Mimic serialization of functions as done in `Extension.generateXPI` and
  // `Extension.generateZipFile` because functions are dropped when `ext` object
  // is sent to the main process via the message manager.
  ext = Object.assign({}, ext);
  if (ext.files) {
    ext.files = Object.assign({}, ext.files);
    for (let filename of Object.keys(ext.files)) {
      let file = ext.files[filename];
      if (typeof file === "function" || Array.isArray(file)) {
        ext.files[filename] = ExtensionTestCommon.serializeScript(file);
      }
    }
  }
  if ("background" in ext) {
    ext.background = ExtensionTestCommon.serializeScript(ext.background);
  }

  var extension = SpecialPowers.loadExtension(ext, handler);

  registerCleanup(async () => {
    if (extension.state == "pending" || extension.state == "running") {
      SimpleTest.ok(false, "Extension left running at test shutdown");
      await extension.unload();
    } else if (extension.state == "unloading") {
      SimpleTest.ok(false, "Extension not fully unloaded at test shutdown");
    }
  });

  extension.awaitMessage = msg => {
    return new Promise(resolve => {
      checkDuplicateListeners(msg);

      messageAwaiter.set(msg, { resolve });
      checkMessages();
    });
  };

  extension.onMessage = (msg, callback) => {
    checkDuplicateListeners(msg);
    messageHandler.set(msg, callback);
  };

  extension.awaitFinish = msg => {
    return testDone.then(actual => {
      if (msg) {
        SimpleTest.is(actual, msg, "test result correct");
      }
      return actual;
    });
  };

  SimpleTest.info(`Extension loaded`);
  return extension;
};

ExtensionTestUtils.failOnSchemaWarnings = (warningsAsErrors = true) => {
  let prefName = "extensions.webextensions.warnings-as-errors";
  SpecialPowers.setBoolPref(prefName, warningsAsErrors);
  if (!warningsAsErrors) {
    let registerCleanup;
    if (typeof registerCleanupFunction != "undefined") {
      registerCleanup = registerCleanupFunction;
    } else {
      registerCleanup = SimpleTest.registerCleanupFunction.bind(SimpleTest);
    }
    registerCleanup(() => SpecialPowers.setBoolPref(prefName, true));
  }
};