var lastElement;

function openContextMenuFor(element, shiftkey, waitForSpellCheck) {
    // Context menu should be closed before we open it again.
    is(SpecialPowers.wrap(contextMenu).state, "closed", "checking if popup is closed");

    if (lastElement)
      lastElement.blur();
    element.focus();

    // Some elements need time to focus and spellcheck before any tests are
    // run on them.
    function actuallyOpenContextMenuFor() {
      lastElement = element;
      var eventDetails = { type : "contextmenu", button : 2, shiftKey : shiftkey };
      synthesizeMouse(element, 2, 2, eventDetails, element.ownerGlobal);
    }

    if (waitForSpellCheck) {
      var { onSpellCheck } = SpecialPowers.Cu.import("resource://gre/modules/AsyncSpellCheckTestHelper.jsm", {});
      onSpellCheck(element, actuallyOpenContextMenuFor);
    }
    else {
      actuallyOpenContextMenuFor();
    }
}

function closeContextMenu() {
    contextMenu.hidePopup();
}

function getVisibleMenuItems(aMenu, aData) {
    var items = [];
    var accessKeys = {};
    for (var i = 0; i < aMenu.childNodes.length; i++) {
        var item = aMenu.childNodes[i];
        if (item.hidden)
            continue;

        var key = item.accessKey;
        if (key)
            key = key.toLowerCase();

        var isPageMenuItem = item.hasAttribute("generateditemid");

        if (item.nodeName == "menuitem") {
            var isGenerated = item.className == "spell-suggestion"
                              || item.className == "sendtab-target";
            if (isGenerated) {
              is(item.id, "", "child menuitem #" + i + " is generated");
            } else if (isPageMenuItem) {
              is(item.id, "", "child menuitem #" + i + " is a generated page menu item");
            } else {
              ok(item.id, "child menuitem #" + i + " has an ID");
            }
            var label = item.getAttribute("label");
            ok(label.length, "menuitem " + item.id + " has a label");
            if (isGenerated) {
              is(key, "", "Generated items shouldn't have an access key");
              items.push("*" + label);
            } else if (isPageMenuItem) {
              items.push("+" + label);
            } else if (item.id.indexOf("spell-check-dictionary-") != 0 &&
                       item.id != "spell-no-suggestions" &&
                       item.id != "spell-add-dictionaries-main" &&
                       item.id != "context-savelinktopocket" &&
                       item.id != "fill-login-saved-passwords" &&
                       item.id != "fill-login-no-logins") {
              ok(key, "menuitem " + item.id + " has an access key");
              if (accessKeys[key])
                  ok(false, "menuitem " + item.id + " has same accesskey as " + accessKeys[key]);
              else
                  accessKeys[key] = item.id;
            }
            if (!isGenerated && !isPageMenuItem) {
              items.push(item.id);
            }
            if (isPageMenuItem) {
              var p = {};
              p.type = item.getAttribute("type");
              p.icon = item.getAttribute("image");
              p.checked = item.hasAttribute("checked");
              p.disabled = item.hasAttribute("disabled");
              items.push(p);
            } else {
              items.push(!item.disabled);
            }
        } else if (item.nodeName == "menuseparator") {
            ok(true, "--- seperator id is " + item.id);
            items.push("---");
            items.push(null);
        } else if (item.nodeName == "menu") {
            if (isPageMenuItem) {
                item.id = "generated-submenu-" + aData.generatedSubmenuId++;
            }
            ok(item.id, "child menu #" + i + " has an ID");
            if (!isPageMenuItem) {
                ok(key, "menu has an access key");
                if (accessKeys[key])
                    ok(false, "menu " + item.id + " has same accesskey as " + accessKeys[key]);
                else
                    accessKeys[key] = item.id;
            }
            items.push(item.id);
            items.push(!item.disabled);
            // Add a dummy item so that the indexes in checkMenu are the same
            // for expectedItems and actualItems.
            items.push([]);
            items.push(null);
        } else if (item.nodeName == "menugroup") {
            ok(item.id, "child menugroup #" + i + " has an ID");
            items.push(item.id);
            items.push(!item.disabled);
            var menugroupChildren = [];
            for (var child of item.children) {
                if (child.hidden)
                    continue;

                menugroupChildren.push([child.id, !child.disabled]);
            }
            items.push(menugroupChildren);
            items.push(null);
        } else {
            ok(false, "child #" + i + " of menu ID " + aMenu.id +
                      " has an unknown type (" + item.nodeName + ")");
        }
    }
    return items;
}

function checkContextMenu(expectedItems) {
    is(contextMenu.state, "open", "checking if popup is open");
    var data = { generatedSubmenuId: 1 };
    checkMenu(contextMenu, expectedItems, data);
}

function checkMenuItem(actualItem, actualEnabled, expectedItem, expectedEnabled, index) {
    is(actualItem, expectedItem,
       "checking item #" + index/2 + " (" + expectedItem + ") name");

    if (typeof expectedEnabled == "object" && expectedEnabled != null ||
        typeof actualEnabled == "object" && actualEnabled != null) {

        ok(!(actualEnabled == null), "actualEnabled is not null");
        ok(!(expectedEnabled == null), "expectedEnabled is not null");
        is(typeof actualEnabled, typeof expectedEnabled, "checking types");

        if (typeof actualEnabled != typeof expectedEnabled ||
            actualEnabled == null || expectedEnabled == null)
          return;

        is(actualEnabled.type, expectedEnabled.type,
           "checking item #" + index/2 + " (" + expectedItem + ") type attr value");
        var icon = actualEnabled.icon;
        if (icon) {
          var tmp = "";
          var j = icon.length - 1;
          while (j && icon[j] != "/") {
            tmp = icon[j--] + tmp;
          }
          icon = tmp;
        }
        is(icon, expectedEnabled.icon,
           "checking item #" + index/2 + " (" + expectedItem + ") icon attr value");
        is(actualEnabled.checked, expectedEnabled.checked,
           "checking item #" + index/2 + " (" + expectedItem + ") has checked attr");
        is(actualEnabled.disabled, expectedEnabled.disabled,
           "checking item #" + index/2 + " (" + expectedItem + ") has disabled attr");
    } else if (expectedEnabled != null)
        is(actualEnabled, expectedEnabled,
           "checking item #" + index/2 + " (" + expectedItem + ") enabled state");
}

/*
 * checkMenu - checks to see if the specified <menupopup> contains the
 * expected items and state.
 * expectedItems is a array of (1) item IDs and (2) a boolean specifying if
 * the item is enabled or not (or null to ignore it). Submenus can be checked
 * by providing a nested array entry after the expected <menu> ID.
 * For example: ["blah", true,              // item enabled
 *               "submenu", null,           // submenu
 *                   ["sub1", true,         // submenu contents
 *                    "sub2", false], null, // submenu contents
 *               "lol", false]              // item disabled
 *
 */
function checkMenu(menu, expectedItems, data) {
    var actualItems = getVisibleMenuItems(menu, data);
    // ok(false, "Items are: " + actualItems);
    for (var i = 0; i < expectedItems.length; i+=2) {
        var actualItem   = actualItems[i];
        var actualEnabled = actualItems[i + 1];
        var expectedItem = expectedItems[i];
        var expectedEnabled = expectedItems[i + 1];
        if (expectedItem instanceof Array) {
            ok(true, "Checking submenu/menugroup...");
            var previousId = expectedItems[i - 2]; // The last item was the menu ID.
            var previousItem = menu.getElementsByAttribute("id", previousId)[0];
            ok(previousItem, (previousItem ? previousItem.nodeName : "item") + " with previous id (" + previousId + ") found");
            if (previousItem && previousItem.nodeName == "menu") {
              ok(previousItem, "got a submenu element of id='" + previousId + "'");
              is(previousItem.nodeName, "menu", "submenu element of id='" + previousId +
                                           "' has expected nodeName");
              checkMenu(previousItem.menupopup, expectedItem, data, i);
            } else if (previousItem && previousItem.nodeName == "menugroup") {
              ok(expectedItem.length, "menugroup must not be empty");
              for (var j = 0; j < expectedItem.length / 2; j++) {
                checkMenuItem(actualItems[i][j][0], actualItems[i][j][1], expectedItem[j*2], expectedItem[j*2+1], i+j*2);
              }
              i += j;
            } else {
              ok(false, "previous item is not a menu or menugroup");
            }
        } else {
            checkMenuItem(actualItem, actualEnabled, expectedItem, expectedEnabled, i);
        }
    }
    // Could find unexpected extra items at the end...
    is(actualItems.length, expectedItems.length, "checking expected number of menu entries");
}

let lastElementSelector = null;
/**
 * Right-clicks on the element that matches `selector` and checks the
 * context menu that appears against the `menuItems` array.
 *
 * @param {String} selector
 *        A selector passed to querySelector to find
 *        the element that will be referenced.
 * @param {Array} menuItems
 *        An array of menuitem ids and their associated enabled state. A state
 *        of null means that it will be ignored. Ids of '---' are used for
 *        menuseparators.
 * @param {Object} options, optional
 *        skipFocusChange: don't move focus to the element before test, useful
 *                         if you want to delay spell-check initialization
 *        offsetX: horizontal mouse offset from the top-left corner of
 *                 the element, optional
 *        offsetY: vertical mouse offset from the top-left corner of the
 *                 element, optional
 *        centered: if true, mouse position is centered in element, defaults
 *                  to true if offsetX and offsetY are not provided
 *        waitForSpellCheck: wait until spellcheck is initialized before
 *                           starting test
 *        preCheckContextMenuFn: callback to run before opening menu
 *        onContextMenuShown: callback to run when the context menu is shown
 *        postCheckContextMenuFn: callback to run after opening menu
 * @return {Promise} resolved after the test finishes
 */
function* test_contextmenu(selector, menuItems, options={}) {
  contextMenu = document.getElementById("contentAreaContextMenu");
  is(contextMenu.state, "closed", "checking if popup is closed");

  // Default to centered if no positioning is defined.
  if (!options.offsetX && !options.offsetY) {
    options.centered = true;
  }

  if (!options.skipFocusChange) {
    yield ContentTask.spawn(gBrowser.selectedBrowser,
                            [lastElementSelector, selector],
                            function*([contentLastElementSelector, contentSelector]) {
      if (contentLastElementSelector) {
        let contentLastElement = content.document.querySelector(contentLastElementSelector);
        contentLastElement.blur();
      }
      let element = content.document.querySelector(contentSelector);
      element.focus();
    });
    lastElementSelector = selector;
    info(`Moved focus to ${selector}`);
  }

  if (options.preCheckContextMenuFn) {
    yield options.preCheckContextMenuFn();
    info("Completed preCheckContextMenuFn");
  }

  if (options.waitForSpellCheck) {
    info("Waiting for spell check");
    yield ContentTask.spawn(gBrowser.selectedBrowser, selector, function*(contentSelector) {
      let {onSpellCheck} = Cu.import("resource://gre/modules/AsyncSpellCheckTestHelper.jsm", {});
      let element = content.document.querySelector(contentSelector);
      yield new Promise(resolve => onSpellCheck(element, resolve));
      info("Spell check running");
    });
  }

  let awaitPopupShown = BrowserTestUtils.waitForEvent(contextMenu, "popupshown");
  yield BrowserTestUtils.synthesizeMouse(selector, options.offsetX || 0, options.offsetY || 0, {
      type: "contextmenu",
      button: 2,
      shiftkey: options.shiftkey,
      centered: options.centered
    },
    gBrowser.selectedBrowser);
  yield awaitPopupShown;
  info("Popup Shown");

  if (options.onContextMenuShown) {
    yield options.onContextMenuShown();
    info("Completed onContextMenuShown");
  }

  if (menuItems) {
    if (Services.prefs.getBoolPref("devtools.inspector.enabled")) {
      let inspectItems = ["---", null,
                          "context-inspect", true];
      menuItems = menuItems.concat(inspectItems);
    }

    checkContextMenu(menuItems);
  }

  let awaitPopupHidden = BrowserTestUtils.waitForEvent(contextMenu, "popuphidden");

  if (options.postCheckContextMenuFn) {
    yield options.postCheckContextMenuFn();
    info("Completed postCheckContextMenuFn");
  }

  contextMenu.hidePopup();
  yield awaitPopupHidden;
}