/* Any copyright is dedicated to the Public Domain.
 * http://creativecommons.org/publicdomain/zero/1.0/ */

"use strict";

// Basic test for dispatch key event API with input type text

const TEST_URI = "data:text/html;charset=utf-8,<input type=text>";

// Map of key codes used in this test.
const KEYCODES = {
  a: 65,
  Backspace: 8,
  h: 72,
  H: 72,
  AltLeft: 18,
  ArrowLeft: 37,
  ArrowRight: 39,
};

// Modifier for move forward shortcut is CTRL+RightArrow on Linux/Windows, ALT+RightArrow
// on Mac.
const isMac = Services.appinfo.OS === "Darwin";
const ALT_MODIFIER = 1;
const CTRL_MODIFIER = 2;
const ARROW_MODIFIER = isMac ? ALT_MODIFIER : CTRL_MODIFIER;

add_task(async function() {
  // The selectionchange event was flagged behind dom.select_events.textcontrols.enabled,
  // which is only true on Nightly and Local builds. Force the pref to true so that
  // the test passes on all channels. See Bug 1309628 for more details.
  info("Enable selectionchange events on input elements");
  await new Promise(resolve => {
    const options = {
      set: [["dom.select_events.textcontrols.enabled", true]],
    };
    SpecialPowers.pushPrefEnv(options, resolve);
  });

  const { client, tab } = await setupTestForUri(TEST_URI);
  is(gBrowser.selectedTab, tab, "Selected tab is the target tab");

  const { Input } = client;

  info("Focus the input on the page");
  await ContentTask.spawn(gBrowser.selectedBrowser, null, function() {
    const input = content.document.querySelector("input");
    input.focus();
    is(input, content.document.activeElement, "Input should be focused");
  });
  await checkInputContent("", 0);

  info("Write 'h'");
  await sendTextKey(Input, "h");
  await checkInputContent("h", 1);

  info("Write 'H'");
  await sendTextKey(Input, "H");
  await checkInputContent("hH", 2);

  info("Send char type event for char [’]");
  await addInputEventListener("input");
  await Input.dispatchKeyEvent({
    type: "char",
    modifiers: 0,
    key: "’",
  });
  await waitForInputEvent();
  await checkInputContent("hH’", 3);

  info("Send Left");
  await sendArrowKey(Input, "ArrowLeft");
  await checkInputContent("hH’", 2);

  info("Write 'a'");
  await sendTextKey(Input, "a");
  await checkInputContent("hHa’", 3);

  info("Send Left");
  await sendArrowKey(Input, "ArrowLeft");
  await checkInputContent("hHa’", 2);

  info("Send Left");
  await sendArrowKey(Input, "ArrowLeft");
  await checkInputContent("hHa’", 1);

  info("Write 'a'");
  await sendTextKey(Input, "a");
  await checkInputContent("haHa’", 2);

  info("Send ALT/CTRL + Right");
  await sendArrowKey(Input, "ArrowRight", ARROW_MODIFIER);
  await checkInputContent("haHa’", 5);

  info("Delete every character in the input");
  await sendBackspace(Input, "haHa");
  await sendBackspace(Input, "haH");
  await sendBackspace(Input, "ha");
  await sendBackspace(Input, "h");
  await sendBackspace(Input, "");

  await client.close();
  ok(true, "The client is closed");

  BrowserTestUtils.removeTab(tab);

  await RemoteAgent.close();
});

/**
 * Send a text key and wait for the input event to be fired.
 */
async function sendTextKey(Input, key) {
  await addInputEventListener("input");

  await dispatchKeyEvent(Input, key, "keyDown");
  await dispatchKeyEvent(Input, key, "keyUp");

  await waitForInputEvent();
}

/**
 * Send an arrow key that will update the position of the cursor in the input and wait
 * for the selectionchange event to be fired.
 */
async function sendArrowKey(Input, arrowKey, modifiers = 0) {
  await addInputEventListener("selectionchange");

  await dispatchKeyEvent(Input, arrowKey, "rawKeyDown", modifiers);
  await dispatchKeyEvent(Input, arrowKey, "keyUp", modifiers);

  await waitForInputEvent();
}

function dispatchKeyEvent(Input, key, type, modifiers = 0) {
  info(`Send ${type} for key ${key}`);
  return Input.dispatchKeyEvent({
    type,
    modifiers,
    windowsVirtualKeyCode: KEYCODES[key],
    key,
  });
}

async function checkInputContent(expectedValue, expectedCaret) {
  const { value, caret } = await ContentTask.spawn(
    gBrowser.selectedBrowser,
    null,
    function() {
      const input = content.document.querySelector("input");
      return { value: input.value, caret: input.selectionStart };
    }
  );

  is(
    value,
    expectedValue,
    `The input value is correct ("${value}"="${expectedValue}")`
  );
  is(
    caret,
    expectedCaret,
    `The input caret has the correct index ("${caret}"="${expectedCaret}")`
  );
}

async function sendBackspace(Input, expected) {
  info("Send Backspace");
  await addInputEventListener("input");

  await dispatchKeyEvent(Input, "Backspace", "rawKeyDown");
  await dispatchKeyEvent(Input, "Backspace", "keyUp");

  await waitForInputEvent();

  await checkInputContent(expected, expected.length);
}

/**
 * Add an event listener on the content page input. This will resolve when the listener is
 * added.
 *
 * Since ContentTask.spawn is asynchronous make sure to await on this method before
 * executing the code that should fire the event. Otherwise the test will be exposed to
 * race conditions where the listener is added too late and is not triggered.
 *
 * Use `waitForInputEvent` afterwards to wait for the event to be fired.
 *
 *   await addInputEventListener("click");
 *   await someCodeThatWillTriggerClick();
 *   await waitForInputEvent();
 */
function addInputEventListener(eventName) {
  return ContentTask.spawn(
    gBrowser.selectedBrowser,
    eventName,
    async _eventName => {
      const input = content.document.querySelector("input");
      this.__onInputEvent = new Promise(r =>
        input.addEventListener(_eventName, r, { once: true })
      );
    }
  );
}

/**
 * See documentation for addInputEventListener.
 */
function waitForInputEvent() {
  return ContentTask.spawn(
    gBrowser.selectedBrowser,
    null,
    () => this.__onInputEvent
  );
}