/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

"use strict";

/* eslint no-unused-vars: [2, {"vars": "local"}] */
/* globals getHighlighterTestFront, openToolboxForTab, gBrowser */
/* import-globals-from ../../shared/test/shared-head.js */

var {
  getInplaceEditorForSpan: inplaceEditor,
} = require("resource://devtools/client/shared/inplace-editor.js");

// This file contains functions related to the inspector that are also of interest to
// other test directores as well.

/**
 * Open the toolbox, with the inspector tool visible.
 * @param {String} hostType Optional hostType, as defined in Toolbox.HostType
 * @return {Promise} A promise that resolves when the inspector is ready.The promise
 *         resolves with an object containing the following properties:
 *           - toolbox
 *           - inspector
 *           - highlighterTestFront
 */
var openInspector = async function (hostType) {
  info("Opening the inspector");

  const toolbox = await openToolboxForTab(
    gBrowser.selectedTab,
    "inspector",
    hostType
  );
  const inspector = toolbox.getPanel("inspector");

  const highlighterTestFront = await getHighlighterTestFront(toolbox);

  return { toolbox, inspector, highlighterTestFront };
};

/**
 * Open the toolbox, with the inspector tool visible, and the one of the sidebar
 * tabs selected.
 *
 * @param {String} id
 *        The ID of the sidebar tab to be opened
 * @return {Promise<Object>} A promise that resolves when the inspector is ready and the tab is
 *         visible and ready. The promise resolves with an object containing the
 *         following properties:
 *           - toolbox
 *           - inspector
 *           - highlighterTestFront
 */
var openInspectorSidebarTab = async function (id) {
  const { toolbox, inspector, highlighterTestFront } = await openInspector();

  info("Selecting the " + id + " sidebar");

  const onSidebarSelect = inspector.sidebar.once("select");
  if (id === "layoutview") {
    // The layout view should wait until the box-model and grid-panel are ready.
    const onBoxModelViewReady = inspector.once("boxmodel-view-updated");
    const onGridPanelReady = inspector.once("grid-panel-updated");
    inspector.sidebar.select(id);
    await onBoxModelViewReady;
    await onGridPanelReady;
  } else {
    inspector.sidebar.select(id);
  }
  await onSidebarSelect;

  return {
    toolbox,
    inspector,
    highlighterTestFront,
  };
};

/**
 * Open the toolbox, with the inspector tool visible, and the rule-view
 * sidebar tab selected.
 *
 * @return a promise that resolves when the inspector is ready and the rule view
 * is visible and ready
 */
async function openRuleView() {
  const { inspector, toolbox, highlighterTestFront } = await openInspector();

  const ruleViewPanel = inspector.getPanel("ruleview");
  await ruleViewPanel.readyPromise;
  const view = ruleViewPanel.view;

  // Replace the view to use a custom debounce function that can be triggered manually
  // through an additional ".flush()" property.
  view.debounce = manualDebounce();

  return {
    toolbox,
    inspector,
    highlighterTestFront,
    view,
  };
}

/**
 * Open the toolbox, with the inspector tool visible, and the computed-view
 * sidebar tab selected.
 *
 * @return a promise that resolves when the inspector is ready and the computed
 * view is visible and ready
 */
function openComputedView() {
  return openInspectorSidebarTab("computedview").then(data => {
    const view = data.inspector.getPanel("computedview").computedView;

    return {
      toolbox: data.toolbox,
      inspector: data.inspector,
      highlighterTestFront: data.highlighterTestFront,
      view,
    };
  });
}

/**
 * Open the toolbox, with the inspector tool visible, and the changes view
 * sidebar tab selected.
 *
 * @return a promise that resolves when the inspector is ready and the changes
 * view is visible and ready
 */
function openChangesView() {
  return openInspectorSidebarTab("changesview").then(data => {
    return {
      toolbox: data.toolbox,
      inspector: data.inspector,
      highlighterTestFront: data.highlighterTestFront,
      view: data.inspector.getPanel("changesview"),
    };
  });
}

/**
 * Open the toolbox, with the inspector tool visible, and the layout view
 * sidebar tab selected to display the box model view with properties.
 *
 * @return {Promise} a promise that resolves when the inspector is ready and the layout
 *         view is visible and ready.
 */
function openLayoutView() {
  return openInspectorSidebarTab("layoutview").then(data => {
    return {
      toolbox: data.toolbox,
      inspector: data.inspector,
      boxmodel: data.inspector.getPanel("boxmodel"),
      gridInspector: data.inspector.getPanel("layoutview").gridInspector,
      flexboxInspector: data.inspector.getPanel("layoutview").flexboxInspector,
      layoutView: data.inspector.getPanel("layoutview"),
      highlighterTestFront: data.highlighterTestFront,
    };
  });
}

/**
 * Select the rule view sidebar tab on an already opened inspector panel.
 *
 * @param {InspectorPanel} inspector
 *        The opened inspector panel
 * @return {CssRuleView} the rule view
 */
function selectRuleView(inspector) {
  return inspector.getPanel("ruleview").view;
}

/**
 * Select the computed view sidebar tab on an already opened inspector panel.
 *
 * @param {InspectorPanel} inspector
 *        The opened inspector panel
 * @return {CssComputedView} the computed view
 */
function selectComputedView(inspector) {
  inspector.sidebar.select("computedview");
  return inspector.getPanel("computedview").computedView;
}

/**
 * Select the changes view sidebar tab on an already opened inspector panel.
 *
 * @param {InspectorPanel} inspector
 *        The opened inspector panel
 * @return {ChangesView} the changes view
 */
function selectChangesView(inspector) {
  inspector.sidebar.select("changesview");
  return inspector.getPanel("changesview");
}

/**
 * Select the layout view sidebar tab on an already opened inspector panel.
 *
 * @param  {InspectorPanel} inspector
 * @return {BoxModel} the box model
 */
function selectLayoutView(inspector) {
  inspector.sidebar.select("layoutview");
  return inspector.getPanel("boxmodel");
}

/**
 * Get the NodeFront for a node that matches a given css selector, via the
 * protocol.
 * @param {String|NodeFront} selector
 * @param {InspectorPanel} inspector The instance of InspectorPanel currently
 * loaded in the toolbox
 * @return {Promise} Resolves to the NodeFront instance
 */
function getNodeFront(selector, { walker }) {
  if (selector._form) {
    return selector;
  }
  return walker.querySelector(walker.rootNode, selector);
}

/**
 * Set the inspector's current selection to the first match of the given css
 * selector
 *
 * @param {String|NodeFront} selector
 * @param {InspectorPanel} inspector
 *        The instance of InspectorPanel currently loaded in the toolbox.
 * @param {String} reason
 *        Defaults to "test" which instructs the inspector not to highlight the
 *        node upon selection.
 * @param {Boolean} isSlotted
 *        Is the selection representing the slotted version the node.
 * @return {Promise} Resolves when the inspector is updated with the new node
 */
var selectNode = async function (
  selector,
  inspector,
  reason = "test",
  isSlotted
) {
  info("Selecting the node for '" + selector + "'");
  const nodeFront = await getNodeFront(selector, inspector);
  const updated = inspector.once("inspector-updated");

  const {
    ELEMENT_NODE,
  } = require("resource://devtools/shared/dom-node-constants.js");
  const onSelectionCssSelectorsUpdated =
    nodeFront?.nodeType == ELEMENT_NODE
      ? inspector.once("selection-css-selectors-updated")
      : null;

  inspector.selection.setNodeFront(nodeFront, { reason, isSlotted });
  await updated;
  await onSelectionCssSelectorsUpdated;
};

/**
 * Using the markupview's _waitForChildren function, wait for all queued
 * children updates to be handled.
 * @param {InspectorPanel} inspector The instance of InspectorPanel currently
 * loaded in the toolbox
 * @return a promise that resolves when all queued children updates have been
 * handled
 */
function waitForChildrenUpdated({ markup }) {
  info("Waiting for queued children updates to be handled");
  return new Promise(resolve => {
    markup._waitForChildren().then(() => {
      executeSoon(resolve);
    });
  });
}

// The expand all operation of the markup-view calls itself recursively and
// there's not one event we can wait for to know when it's done, so use this
// helper function to wait until all recursive children updates are done.
async function waitForMultipleChildrenUpdates(inspector) {
  // As long as child updates are queued up while we wait for an update already
  // wait again
  if (
    inspector.markup._queuedChildUpdates &&
    inspector.markup._queuedChildUpdates.size
  ) {
    await waitForChildrenUpdated(inspector);
    return waitForMultipleChildrenUpdates(inspector);
  }
  return null;
}

/**
 * Expand the provided markup container programmatically and  wait for all
 * children to update.
 */
async function expandContainer(inspector, container) {
  await inspector.markup.expandNode(container.node);
  await waitForMultipleChildrenUpdates(inspector);
}

/**
 * Get the NodeFront for a node that matches a given css selector inside a
 * given iframe.
 *
 * @param {Array} selectors
 *        Arrays of CSS selectors from the root document to the node.
 *        The last CSS selector of the array is for the node in its frame doc.
 *        The before-last CSS selector is for the frame in its parent frame, etc...
 *        Ex: ["frame.first-frame", ..., "frame.last-frame", ".target-node"]
 * @param {InspectorPanel} inspector
 *        See `selectNode`
 * @return {NodeFront} Resolves the corresponding node front.
 */
async function getNodeFrontInFrames(selectors, inspector) {
  let walker = inspector.walker;
  let rootNode = walker.rootNode;

  // clone the array since `selectors` could be used from callsite after.
  selectors = [...selectors];
  // Extract the last selector from the provided array of selectors.
  const nodeSelector = selectors.pop();

  // Remaining selectors should all be frame selectors. Renaming for clarity.
  const frameSelectors = selectors;

  info("Loop through all frame selectors");
  for (const frameSelector of frameSelectors) {
    const url = walker.targetFront.url;
    info(`Find the frame element for selector ${frameSelector} in ${url}`);

    const frameNodeFront = await walker.querySelector(rootNode, frameSelector);

    // If needed, connect to the corresponding frame target.
    // Otherwise, reuse the current targetFront.
    let frameTarget = frameNodeFront.targetFront;
    if (frameNodeFront.useChildTargetToFetchChildren) {
      info("Connect to frame and retrieve the targetFront");
      frameTarget = await frameNodeFront.connectToFrame();
    }

    walker = (await frameTarget.getFront("inspector")).walker;

    if (frameNodeFront.useChildTargetToFetchChildren) {
      // For frames or browser elements, use the walker's rootNode.
      rootNode = walker.rootNode;
    } else {
      // For same-process frames, select the document front as the root node.
      // It is a different node from the walker's rootNode.
      info("Retrieve the children of the frame to find the document node");
      const { nodes } = await walker.children(frameNodeFront);
      rootNode = nodes.find(n => n.nodeType === Node.DOCUMENT_NODE);
    }
  }

  return walker.querySelector(rootNode, nodeSelector);
}

/**
 * Helper to select a node in the markup-view, in a nested tree of
 * frames/browser elements. The iframes can either be remote or same-process.
 *
 * Note: "frame" will refer to either "frame" or "browser" in the documentation
 * and method.
 *
 * @param {Array} selectors
 *        Arrays of CSS selectors from the root document to the node.
 *        The last CSS selector of the array is for the node in its frame doc.
 *        The before-last CSS selector is for the frame in its parent frame, etc...
 *        Ex: ["frame.first-frame", ..., "frame.last-frame", ".target-node"]
 * @param {InspectorPanel} inspector
 *        See `selectNode`
 * @param {String} reason
 *        See `selectNode`
 * @param {Boolean} isSlotted
 *        See `selectNode`
 * @return {NodeFront} The selected node front.
 */
async function selectNodeInFrames(
  selectors,
  inspector,
  reason = "test",
  isSlotted
) {
  const nodeFront = await getNodeFrontInFrames(selectors, inspector);
  await selectNode(nodeFront, inspector, reason, isSlotted);
  return nodeFront;
}

/**
 * Create a throttling function that can be manually "flushed". This is to replace the
 * use of the `debounce` function from `devtools/client/inspector/shared/utils.js`, which
 * has a setTimeout that can cause intermittents.
 * @return {Function} This function has the same function signature as debounce, but
 *                    the property `.flush()` has been added for flushing out any
 *                    debounced calls.
 */
function manualDebounce() {
  let calls = [];

  function debounce(func, wait, scope) {
    return function () {
      const existingCall = calls.find(call => call.func === func);
      if (existingCall) {
        existingCall.args = arguments;
      } else {
        calls.push({ func, wait, scope, args: arguments });
      }
    };
  }

  debounce.flush = function () {
    calls.forEach(({ func, scope, args }) => func.apply(scope, args));
    calls = [];
  };

  return debounce;
}

/**
 * Get the requested rule style property from the current browser.
 *
 * @param {Number} styleSheetIndex
 * @param {Number} ruleIndex
 * @param {String} name
 * @return {String} The value, if found, null otherwise
 */

async function getRulePropertyValue(styleSheetIndex, ruleIndex, name) {
  return SpecialPowers.spawn(
    gBrowser.selectedBrowser,
    [styleSheetIndex, ruleIndex, name],
    (styleSheetIndexChild, ruleIndexChild, nameChild) => {
      let value = null;

      info(
        "Getting the value for property name " +
          nameChild +
          " in sheet " +
          styleSheetIndexChild +
          " and rule " +
          ruleIndexChild
      );

      const sheet = content.document.styleSheets[styleSheetIndexChild];
      if (sheet) {
        const rule = sheet.cssRules[ruleIndexChild];
        if (rule) {
          value = rule.style.getPropertyValue(nameChild);
        }
      }

      return value;
    }
  );
}

/**
 * Get the requested computed style property from the current browser.
 *
 * @param {String} selector
 *        The selector used to obtain the element.
 * @param {String} pseudo
 *        pseudo id to query, or null.
 * @param {String} propName
 *        name of the property.
 */
async function getComputedStyleProperty(selector, pseudo, propName) {
  return SpecialPowers.spawn(
    gBrowser.selectedBrowser,
    [selector, pseudo, propName],
    (selectorChild, pseudoChild, propNameChild) => {
      const element = content.document.querySelector(selectorChild);
      return content.document.defaultView
        .getComputedStyle(element, pseudoChild)
        .getPropertyValue(propNameChild);
    }
  );
}

/**
 * Wait until the requested computed style property has the
 * expected value in the the current browser.
 *
 * @param {String} selector
 *        The selector used to obtain the element.
 * @param {String} pseudo
 *        pseudo id to query, or null.
 * @param {String} propName
 *        name of the property.
 * @param {String} expected
 *        expected value of property
 */
async function waitForComputedStyleProperty(
  selector,
  pseudo,
  propName,
  expected
) {
  return SpecialPowers.spawn(
    gBrowser.selectedBrowser,
    [selector, pseudo, propName, expected],
    (selectorChild, pseudoChild, propNameChild, expectedChild) => {
      const element = content.document.querySelector(selectorChild);
      return ContentTaskUtils.waitForCondition(() => {
        const value = content.document.defaultView
          .getComputedStyle(element, pseudoChild)
          .getPropertyValue(propNameChild);
        return value === expectedChild;
      });
    }
  );
}

/**
 * Given an inplace editable element, click to switch it to edit mode, wait for
 * focus
 *
 * @return a promise that resolves to the inplace-editor element when ready
 */
var focusEditableField = async function (
  ruleView,
  editable,
  xOffset = 1,
  yOffset = 1,
  options = {}
) {
  editable.scrollIntoView();
  const onFocus = once(editable.parentNode, "focus", true);
  info("Clicking on editable field to turn to edit mode");
  if (options.type === undefined) {
    // "mousedown" and "mouseup" flushes any pending layout.  Therefore,
    // if the caller wants to click an element, e.g., closebrace to add new
    // property, we need to guarantee that the element is clicked here even
    // if it's moved by flushing the layout because whether the UI is useful
    // or not when there is pending reflow is not scope of the tests.
    options.type = "mousedown";
    EventUtils.synthesizeMouse(
      editable,
      xOffset,
      yOffset,
      options,
      editable.ownerGlobal
    );
    options.type = "mouseup";
    EventUtils.synthesizeMouse(
      editable,
      xOffset,
      yOffset,
      options,
      editable.ownerGlobal
    );
  } else {
    EventUtils.synthesizeMouse(
      editable,
      xOffset,
      yOffset,
      options,
      editable.ownerGlobal
    );
  }
  await onFocus;

  info("Editable field gained focus, returning the input field now");
  const onEdit = inplaceEditor(editable.ownerDocument.activeElement);

  return onEdit;
};

/**
 * Get the DOMNode for a css rule in the rule-view that corresponds to the given
 * selector.
 *
 * @param {CssRuleView} view
 *        The instance of the rule-view panel
 * @param {String} selectorText
 *        The selector in the rule-view for which the rule
 *        object is wanted
 * @param {Number} index
 *        If there are more than 1 rule with the same selector, you may pass a
 *        index to determine which of the rules you want.
 * @return {DOMNode}
 */
function getRuleViewRule(view, selectorText, index = 0) {
  let rule;
  let pos = 0;
  for (const r of view.styleDocument.querySelectorAll(".ruleview-rule")) {
    const selector = r.querySelector(
      ".ruleview-selectors-container, .ruleview-selector.matched"
    );
    if (selector && selector.textContent === selectorText) {
      if (index == pos) {
        rule = r;
        break;
      }
      pos++;
    }
  }

  return rule;
}

/**
 * Get references to the name and value span nodes corresponding to a given
 * selector and property name in the rule-view.
 *
 * @param {CssRuleView} view
 *        The instance of the rule-view panel
 * @param {String} selectorText
 *        The selector in the rule-view to look for the property in
 * @param {String} propertyName
 *        The name of the property
 * @param {Object=} options
 * @param {Boolean=} options.wait
 *        When true, returns a promise which waits until a valid rule view
 *        property can be retrieved for the provided selectorText & propertyName.
 *        Defaults to false.
 * @return {Object} An object like {nameSpan: DOMNode, valueSpan: DOMNode}
 */
function getRuleViewProperty(view, selectorText, propertyName, options = {}) {
  if (options.wait) {
    return waitFor(() =>
      _syncGetRuleViewProperty(view, selectorText, propertyName)
    );
  }
  return _syncGetRuleViewProperty(view, selectorText, propertyName);
}

function _syncGetRuleViewProperty(view, selectorText, propertyName) {
  const rule = getRuleViewRule(view, selectorText);
  if (!rule) {
    return null;
  }

  // Look for the propertyName in that rule element
  for (const p of rule.querySelectorAll(".ruleview-property")) {
    const nameSpan = p.querySelector(".ruleview-propertyname");
    const valueSpan = p.querySelector(".ruleview-propertyvalue");

    if (nameSpan.textContent === propertyName) {
      return { nameSpan, valueSpan };
    }
  }
  return null;
}

/**
 * Get the text value of the property corresponding to a given selector and name
 * in the rule-view
 *
 * @param {CssRuleView} view
 *        The instance of the rule-view panel
 * @param {String} selectorText
 *        The selector in the rule-view to look for the property in
 * @param {String} propertyName
 *        The name of the property
 * @return {String} The property value
 */
function getRuleViewPropertyValue(view, selectorText, propertyName) {
  return getRuleViewProperty(view, selectorText, propertyName).valueSpan
    .textContent;
}

/**
 * Get a reference to the selector DOM element corresponding to a given selector
 * in the rule-view
 *
 * @param {CssRuleView} view
 *        The instance of the rule-view panel
 * @param {String} selectorText
 *        The selector in the rule-view to look for
 * @return {DOMNode} The selector DOM element
 */
function getRuleViewSelector(view, selectorText) {
  const rule = getRuleViewRule(view, selectorText);
  return rule.querySelector(
    ".ruleview-selectors-container, .ruleview-selector.matched"
  );
}

/**
 * Get a rule-link from the rule-view given its index
 *
 * @param {CssRuleView} view
 *        The instance of the rule-view panel
 * @param {Number} index
 *        The index of the link to get
 * @return {DOMNode} The link if any at this index
 */
function getRuleViewLinkByIndex(view, index) {
  const links = view.styleDocument.querySelectorAll(".ruleview-rule-source");
  return links[index];
}

/**
 * Get rule-link text from the rule-view given its index
 *
 * @param {CssRuleView} view
 *        The instance of the rule-view panel
 * @param {Number} index
 *        The index of the link to get
 * @return {String} The string at this index
 */
function getRuleViewLinkTextByIndex(view, index) {
  const link = getRuleViewLinkByIndex(view, index);
  return link.querySelector(".ruleview-rule-source-label").textContent;
}

/**
 * Click on a rule-view's close brace to focus a new property name editor
 *
 * @param {RuleEditor} ruleEditor
 *        An instance of RuleEditor that will receive the new property
 * @return a promise that resolves to the newly created editor when ready and
 * focused
 */
var focusNewRuleViewProperty = async function (ruleEditor) {
  info("Clicking on a close ruleEditor brace to start editing a new property");

  // Use bottom alignment to avoid scrolling out of the parent element area.
  ruleEditor.closeBrace.scrollIntoView(false);
  const editor = await focusEditableField(
    ruleEditor.ruleView,
    ruleEditor.closeBrace
  );

  is(
    inplaceEditor(ruleEditor.newPropSpan),
    editor,
    "Focused editor is the new property editor."
  );

  return editor;
};

/**
 * Create a new property name in the rule-view, focusing a new property editor
 * by clicking on the close brace, and then entering the given text.
 * Keep in mind that the rule-view knows how to handle strings with multiple
 * properties, so the input text may be like: "p1:v1;p2:v2;p3:v3".
 *
 * @param {RuleEditor} ruleEditor
 *        The instance of RuleEditor that will receive the new property(ies)
 * @param {String} inputValue
 *        The text to be entered in the new property name field
 * @return a promise that resolves when the new property name has been entered
 * and once the value field is focused
 */
var createNewRuleViewProperty = async function (ruleEditor, inputValue) {
  info("Creating a new property editor");
  const editor = await focusNewRuleViewProperty(ruleEditor);

  info("Entering the value " + inputValue);
  editor.input.value = inputValue;

  info("Submitting the new value and waiting for value field focus");
  const onFocus = once(ruleEditor.element, "focus", true);
  EventUtils.synthesizeKey(
    "VK_RETURN",
    {},
    ruleEditor.element.ownerDocument.defaultView
  );
  await onFocus;
};

/**
 * Set the search value for the rule-view filter styles search box.
 *
 * @param {CssRuleView} view
 *        The instance of the rule-view panel
 * @param {String} searchValue
 *        The filter search value
 * @return a promise that resolves when the rule-view is filtered for the
 * search term
 */
var setSearchFilter = async function (view, searchValue) {
  info('Setting filter text to "' + searchValue + '"');

  const searchField = view.searchField;
  searchField.focus();

  for (const key of searchValue.split("")) {
    EventUtils.synthesizeKey(key, {}, view.styleWindow);
  }

  await view.inspector.once("ruleview-filtered");
};

/**
 * Flatten all context menu items into a single array to make searching through
 * it easier.
 */
function buildContextMenuItems(menu) {
  const allItems = [].concat.apply(
    [],
    menu.items.map(function addItem(item) {
      if (item.submenu) {
        return addItem(item.submenu.items);
      }
      return item;
    })
  );

  return allItems;
}

/**
 * Open the style editor context menu and return all of it's items in a flat array
 * @param {CssRuleView} view
 *        The instance of the rule-view panel
 * @return An array of MenuItems
 */
function openStyleContextMenuAndGetAllItems(view, target) {
  const menu = view.contextMenu._openMenu({ target });
  return buildContextMenuItems(menu);
}

/**
 * Open the inspector menu and return all of it's items in a flat array
 * @param {InspectorPanel} inspector
 * @param {Object} options to pass into openMenu
 * @return An array of MenuItems
 */
function openContextMenuAndGetAllItems(inspector, options) {
  const menu = inspector.markup.contextMenu._openMenu(options);
  return buildContextMenuItems(menu);
}

/**
 * Wait until the elements the given selectors indicate come to have the visited state.
 *
 * @param {Tab} tab
 *        The tab where the elements on.
 * @param {Array} selectors
 *        The selectors for the elements.
 */
async function waitUntilVisitedState(tab, selectors) {
  await asyncWaitUntil(async () => {
    const hasVisitedState = await ContentTask.spawn(
      tab.linkedBrowser,
      selectors,
      args => {
        // ElementState::VISITED
        const ELEMENT_STATE_VISITED = 1 << 18;

        for (const selector of args) {
          const target =
            content.wrappedJSObject.document.querySelector(selector);
          if (
            !(
              target &&
              InspectorUtils.getContentState(target) & ELEMENT_STATE_VISITED
            )
          ) {
            return false;
          }
        }
        return true;
      }
    );
    return hasVisitedState;
  });
}

/**
 * Return wether or not the passed selector matches an element in the content page.
 *
 * @param {string} selector
 * @returns Promise<Boolean>
 */
function hasMatchingElementInContentPage(selector) {
  return SpecialPowers.spawn(
    gBrowser.selectedBrowser,
    [selector],
    function (innerSelector) {
      return content.document.querySelector(innerSelector) !== null;
    }
  );
}

/**
 * Return the number of elements matching the passed selector.
 *
 * @param {string} selector
 * @returns Promise<Number> the number of matching elements
 */
function getNumberOfMatchingElementsInContentPage(selector) {
  return SpecialPowers.spawn(
    gBrowser.selectedBrowser,
    [selector],
    function (innerSelector) {
      return content.document.querySelectorAll(innerSelector).length;
    }
  );
}

/**
 * Get the property of an element in the content page
 *
 * @param {string} selector: The selector to get the element we want the property of
 * @param {string} propertyName: The name of the property we want the value of
 * @returns {Promise} A promise that returns with the value of the property for the element
 */
function getContentPageElementProperty(selector, propertyName) {
  return SpecialPowers.spawn(
    gBrowser.selectedBrowser,
    [selector, propertyName],
    function (innerSelector, innerPropertyName) {
      return content.document.querySelector(innerSelector)[innerPropertyName];
    }
  );
}

/**
 * Set the property of an element in the content page
 *
 * @param {string} selector: The selector to get the element we want to set the property on
 * @param {string} propertyName: The name of the property we want to set
 * @param {string} propertyValue: The value that is going to be assigned to the property
 * @returns {Promise}
 */
function setContentPageElementProperty(selector, propertyName, propertyValue) {
  return SpecialPowers.spawn(
    gBrowser.selectedBrowser,
    [selector, propertyName, propertyValue],
    function (innerSelector, innerPropertyName, innerPropertyValue) {
      content.document.querySelector(innerSelector)[innerPropertyName] =
        innerPropertyValue;
    }
  );
}

/**
 * Get all the attributes for a DOM Node living in the content page.
 *
 * @param {String} selector The node selector
 * @returns {Array<Object>} An array of {name, value} objects.
 */
async function getContentPageElementAttributes(selector) {
  return SpecialPowers.spawn(
    gBrowser.selectedBrowser,
    [selector],
    _selector => {
      const node = content.document.querySelector(_selector);
      return Array.from(node.attributes).map(({ name, value }) => ({
        name,
        value,
      }));
    }
  );
}

/**
 * Get an attribute on a DOM Node living in the content page.
 *
 * @param {String} selector The node selector
 * @param {String} attribute The attribute name
 * @return {String} value The attribute value
 */
async function getContentPageElementAttribute(selector, attribute) {
  return SpecialPowers.spawn(
    gBrowser.selectedBrowser,
    [selector, attribute],
    (_selector, _attribute) => {
      return content.document.querySelector(_selector).getAttribute(_attribute);
    }
  );
}

/**
 * Set an attribute on a DOM Node living in the content page.
 *
 * @param {String} selector The node selector
 * @param {String} attribute The attribute name
 * @param {String} value The attribute value
 */
async function setContentPageElementAttribute(selector, attribute, value) {
  return SpecialPowers.spawn(
    gBrowser.selectedBrowser,
    [selector, attribute, value],
    (_selector, _attribute, _value) => {
      content.document
        .querySelector(_selector)
        .setAttribute(_attribute, _value);
    }
  );
}

/**
 * Remove an attribute from a DOM Node living in the content page.
 *
 * @param {String} selector The node selector
 * @param {String} attribute The attribute name
 */
async function removeContentPageElementAttribute(selector, attribute) {
  return SpecialPowers.spawn(
    gBrowser.selectedBrowser,
    [selector, attribute],
    (_selector, _attribute) => {
      content.document.querySelector(_selector).removeAttribute(_attribute);
    }
  );
}

/**
 * Get the rule editor from the rule-view given its index
 *
 * @param {CssRuleView} ruleView
 *        The instance of the rule-view panel
 * @param {Number} childrenIndex
 *        The children index of the element to get
 * @param {Number} nodeIndex
 *        The child node index of the element to get
 * @return {DOMNode} The rule editor if any at this index
 */
function getRuleViewRuleEditor(ruleView, childrenIndex, nodeIndex) {
  const child = ruleView.element.children[childrenIndex];
  if (!child) {
    return null;
  }

  return nodeIndex !== undefined
    ? child.childNodes[nodeIndex]?._ruleEditor
    : child._ruleEditor;
}

/**
 * Get the TextProperty instance corresponding to a CSS declaration
 * from a CSS rule in the Rules view.
 *
 * @param  {RuleView} ruleView
 *         Instance of RuleView.
 * @param  {Number} ruleIndex
 *         The index of the CSS rule where to find the declaration.
 * @param  {Object} declaration
 *         An object representing the target declaration e.g. { color: red }.
 *         The first TextProperty instance which matches will be returned.
 * @return {TextProperty}
 */
function getTextProperty(ruleView, ruleIndex, declaration) {
  const ruleEditor = getRuleViewRuleEditor(ruleView, ruleIndex);
  const [[name, value]] = Object.entries(declaration);
  const textProp = ruleEditor.rule.textProps.find(prop => {
    return prop.name === name && prop.value === value;
  });

  if (!textProp) {
    throw Error(
      `Declaration ${name}:${value} not found on rule at index ${ruleIndex}`
    );
  }

  return textProp;
}

/**
 * Simulate changing the value of a property in a rule in the rule-view.
 *
 * @param {CssRuleView} ruleView
 *        The instance of the rule-view panel
 * @param {TextProperty} textProp
 *        The instance of the TextProperty to be changed
 * @param {String} value
 *        The new value to be used. If null is passed, then the value will be
 *        deleted
 * @param {Object} options
 * @param {Boolean} options.blurNewProperty
 *        After the value has been changed, a new property would have been
 *        focused. This parameter is true by default, and that causes the new
 *        property to be blurred. Set to false if you don't want this.
 * @param {number} options.flushCount
 *        The ruleview uses a manual flush for tests only, and some properties are
 *        only updated after several flush. Allow tests to trigger several flushes
 *        if necessary. Defaults to 1.
 */
async function setProperty(
  ruleView,
  textProp,
  value,
  { blurNewProperty = true, flushCount = 1 } = {}
) {
  info("Set property to: " + value);
  await focusEditableField(ruleView, textProp.editor.valueSpan);

  // Because of the manual flush approach used for tests, we might have an
  // unknown number of debounced "preview" requests . Each preview should
  // synchronously emit "start-preview-property-value".
  // Listen to both this event and "ruleview-changed" which is emitted at the
  // end of a preview and make sure each preview completes successfully.
  let previewStartedCounter = 0;
  const onStartPreview = () => previewStartedCounter++;
  ruleView.on("start-preview-property-value", onStartPreview);

  let previewCounter = 0;
  const onPreviewApplied = () => previewCounter++;
  ruleView.on("ruleview-changed", onPreviewApplied);

  if (value === null) {
    const onPopupOpened = once(ruleView.popup, "popup-opened");
    EventUtils.synthesizeKey("VK_DELETE", {}, ruleView.styleWindow);
    await onPopupOpened;
  } else {
    await wait(500);
    EventUtils.sendString(value, ruleView.styleWindow);
  }

  info(`Flush debounced ruleview methods (remaining: ${flushCount})`);
  ruleView.debounce.flush();
  await waitFor(() => previewCounter >= previewStartedCounter);

  flushCount--;

  while (flushCount > 0) {
    // Wait for some time before triggering a new flush to let new debounced
    // functions queue in-between.
    await wait(100);

    info(`Flush debounced ruleview methods (remaining: ${flushCount})`);
    ruleView.debounce.flush();
    await waitFor(() => previewCounter >= previewStartedCounter);

    flushCount--;
  }

  ruleView.off("start-preview-property-value", onStartPreview);
  ruleView.off("ruleview-changed", onPreviewApplied);

  const onValueDone = ruleView.once("ruleview-changed");
  // In case the popup was opened, wait until it closes
  let onPopupClosed;
  if (ruleView.popup?.isOpen) {
    // it might happen that the popup is still in the process of being opened,
    // so wait until it's properly opened
    await ruleView.popup._pendingShowPromise;
    onPopupClosed = once(ruleView.popup, "popup-closed");
  }

  EventUtils.synthesizeKey(
    blurNewProperty ? "VK_RETURN" : "VK_TAB",
    {},
    ruleView.styleWindow
  );

  info("Waiting for another ruleview-changed after setting property");
  await onValueDone;

  const focusNextOnEnter = Services.prefs.getBoolPref(
    "devtools.inspector.rule-view.focusNextOnEnter"
  );
  if (blurNewProperty && !focusNextOnEnter) {
    info("Force blur on the active element");
    ruleView.styleDocument.activeElement.blur();
  }
  await onPopupClosed;
}