gecko/browser/devtools/shared/widgets/Tooltip.js

/* 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";

const {Cc, Cu, Ci} = require("chrome");
const promise = require("sdk/core/promise");
const IOService = Cc["@mozilla.org/network/io-service;1"]
  .getService(Ci.nsIIOService);
const {Spectrum} = require("devtools/shared/widgets/Spectrum");
const EventEmitter = require("devtools/toolkit/event-emitter");
const {colorUtils} = require("devtools/css-color");
const Heritage = require("sdk/core/heritage");
const {CSSTransformPreviewer} = require("devtools/shared/widgets/CSSTransformPreviewer");

Cu.import("resource://gre/modules/Services.jsm");
Cu.import("resource://gre/modules/XPCOMUtils.jsm");

XPCOMUtils.defineLazyModuleGetter(this, "setNamedTimeout",
  "resource:///modules/devtools/ViewHelpers.jsm");
XPCOMUtils.defineLazyModuleGetter(this, "clearNamedTimeout",
  "resource:///modules/devtools/ViewHelpers.jsm");
XPCOMUtils.defineLazyModuleGetter(this, "VariablesView",
  "resource:///modules/devtools/VariablesView.jsm");
XPCOMUtils.defineLazyModuleGetter(this, "VariablesViewController",
  "resource:///modules/devtools/VariablesViewController.jsm");

const GRADIENT_RE = /\b(repeating-)?(linear|radial)-gradient\(((rgb|hsl)a?\(.+?\)|[^\)])+\)/gi;
const BORDERCOLOR_RE = /^border-[-a-z]*color$/ig;
const BORDER_RE = /^border(-(top|bottom|left|right))?$/ig;
const XHTML_NS = "http://www.w3.org/1999/xhtml";
const SPECTRUM_FRAME = "chrome://browser/content/devtools/spectrum-frame.xhtml";
const ESCAPE_KEYCODE = Ci.nsIDOMKeyEvent.DOM_VK_ESCAPE;
const RETURN_KEYCODE = Ci.nsIDOMKeyEvent.DOM_VK_RETURN;
const POPUP_EVENTS = ["shown", "hidden", "showing", "hiding"];

/**
 * Tooltip widget.
 *
 * This widget is intended at any tool that may need to show rich content in the
 * form of floating panels.
 * A common use case is image previewing in the CSS rule view, but more complex
 * use cases may include color pickers, object inspection, etc...
 *
 * Tooltips are based on XUL (namely XUL arrow-type <panel>s), and therefore
 * need a XUL Document to live in.
 * This is pretty much the only requirement they have on their environment.
 *
 * The way to use a tooltip is simply by instantiating a tooltip yourself and
 * attaching some content in it, or using one of the ready-made content types.
 *
 * A convenient `startTogglingOnHover` method may avoid having to register event
 * handlers yourself if the tooltip has to be shown when hovering over a
 * specific element or group of elements (which is usually the most common case)
 */

/**
 * Container used for dealing with optional parameters.
 *
 * @param {Object} defaults
 *        An object with all default options {p1: v1, p2: v2, ...}
 * @param {Object} options
 *        The actual values.
 */
function OptionsStore(defaults, options) {
  this.defaults = defaults || {};
  this.options = options || {};
}

OptionsStore.prototype = {
  /**
   * Get the value for a given option name.
   * @return {Object} Returns the value for that option, coming either for the
   *         actual values that have been set in the constructor, or from the
   *         defaults if that options was not specified.
   */
  get: function(name) {
    if (typeof this.options[name] !== "undefined") {
      return this.options[name];
    } else {
      return this.defaults[name];
    }
  }
};

/**
 * The low level structure of a tooltip is a XUL element (a <panel>).
 */
let PanelFactory = {
  /**
   * Get a new XUL panel instance.
   * @param {XULDocument} doc
   *        The XUL document to put that panel into
   * @param {OptionsStore} options
   *        An options store to get some configuration from
   */
  get: function(doc, options) {
    // Create the tooltip
    let panel = doc.createElement("panel");
    panel.setAttribute("hidden", true);
    panel.setAttribute("ignorekeys", true);

    panel.setAttribute("consumeoutsideclicks", options.get("consumeOutsideClick"));
    panel.setAttribute("noautofocus", options.get("noAutoFocus"));
    panel.setAttribute("type", "arrow");
    panel.setAttribute("level", "top");

    panel.setAttribute("class", "devtools-tooltip theme-tooltip-panel");
    doc.querySelector("window").appendChild(panel);

    return panel;
  }
};

/**
 * Tooltip class.
 *
 * Basic usage:
 *   let t = new Tooltip(xulDoc);
 *   t.content = someXulContent;
 *   t.show();
 *   t.hide();
 *   t.destroy();
 *
 * Better usage:
 *   let t = new Tooltip(xulDoc);
 *   t.startTogglingOnHover(container, target => {
 *     if (<condition based on target>) {
 *       t.setImageContent("http://image.png");
 *       return true;
 *     }
 *   });
 *   t.destroy();
 *
 * @param {XULDocument} doc
 *        The XUL document hosting this tooltip
 * @param {Object} options
 *        Optional options that give options to consumers:
 *        - consumeOutsideClick {Boolean} Wether the first click outside of the
 *        tooltip should close the tooltip and be consumed or not.
 *        Defaults to false.
 *        - closeOnKeys {Array} An array of key codes that should close the
 *        tooltip. Defaults to [27] (escape key).
 *        - closeOnEvents [{emitter: {Object}, event: {String}, useCapture: {Boolean}}]
 *        Provide an optional list of emitter objects and event names here to
 *        trigger the closing of the tooltip when these events are fired by the
 *        emitters. The emitter objects should either implement on/off(event, cb)
 *        or addEventListener/removeEventListener(event, cb). Defaults to [].
 *        For instance, the following would close the tooltip whenever the
 *        toolbox selects a new tool and when a DOM node gets scrolled:
 *        new Tooltip(doc, {
 *          closeOnEvents: [
 *            {emitter: toolbox, event: "select"},
 *            {emitter: myContainer, event: "scroll", useCapture: true}
 *          ]
 *        });
 *        - noAutoFocus {Boolean} Should the focus automatically go to the panel
 *        when it opens. Defaults to true.
 *
 * Fires these events:
 * - showing : just before the tooltip shows
 * - shown : when the tooltip is shown
 * - hiding : just before the tooltip closes
 * - hidden : when the tooltip gets hidden
 * - keypress : when any key gets pressed, with keyCode
 */
function Tooltip(doc, options) {
  EventEmitter.decorate(this);

  this.doc = doc;
  this.options = new OptionsStore({
    consumeOutsideClick: false,
    closeOnKeys: [ESCAPE_KEYCODE],
    noAutoFocus: true,
    closeOnEvents: []
  }, options);
  this.panel = PanelFactory.get(doc, this.options);

  // Used for namedTimeouts in the mouseover handling
  this.uid = "tooltip-" + Date.now();

  // Emit show/hide events
  for (let event of POPUP_EVENTS) {
    this["_onPopup" + event] = ((e) => {
      return () => this.emit(e);
    })(event);
    this.panel.addEventListener("popup" + event,
      this["_onPopup" + event], false);
  }

  // Listen to keypress events to close the tooltip if configured to do so
  let win = this.doc.querySelector("window");
  this._onKeyPress = event => {
    this.emit("keypress", event.keyCode);
    if (this.options.get("closeOnKeys").indexOf(event.keyCode) !== -1) {
      if (!this.panel.hidden) {
        event.stopPropagation();
      }
      this.hide();
    }
  };
  win.addEventListener("keypress", this._onKeyPress, false);

  // Listen to custom emitters' events to close the tooltip
  this.hide = this.hide.bind(this);
  let closeOnEvents = this.options.get("closeOnEvents");
  for (let {emitter, event, useCapture} of closeOnEvents) {
    for (let add of ["addEventListener", "on"]) {
      if (add in emitter) {
        emitter[add](event, this.hide, useCapture);
        break;
      }
    }
  }
}

module.exports.Tooltip = Tooltip;

Tooltip.prototype = {
  defaultPosition: "before_start",
  defaultOffsetX: 0, // px
  defaultOffsetY: 0, // px
  defaultShowDelay: 50, // ms

  /**
   * Show the tooltip. It might be wise to append some content first if you
   * don't want the tooltip to be empty. You may access the content of the
   * tooltip by setting a XUL node to t.content.
   * @param {node} anchor
   *        Which node should the tooltip be shown on
   * @param {string} position [optional]
   *        Optional tooltip position. Defaults to before_start
   *        https://developer.mozilla.org/en-US/docs/XUL/PopupGuide/Positioning
   * @param {number} x, y [optional]
   *        The left and top offset coordinates, in pixels.
   */
  show: function(anchor,
    position = this.defaultPosition,
    x = this.defaultOffsetX,
    y = this.defaultOffsetY) {
    this.panel.hidden = false;
    this.panel.openPopup(anchor, position, x, y);
  },

  /**
   * Hide the tooltip
   */
  hide: function() {
    this.panel.hidden = true;
    this.panel.hidePopup();
  },

  isShown: function() {
    return this.panel.state !== "closed" && this.panel.state !== "hiding";
  },

  setSize: function(width, height) {
    this.panel.sizeTo(width, height);
  },

  /**
   * Empty the tooltip's content
   */
  empty: function() {
    while (this.panel.hasChildNodes()) {
      this.panel.removeChild(this.panel.firstChild);
    }
  },

  /**
   * Gets this panel's visibility state.
   * @return boolean
   */
  isHidden: function() {
    return this.panel.state == "closed" || this.panel.state == "hiding";
  },

  /**
   * Gets if this panel has any child nodes.
   * @return boolean
   */
  isEmpty: function() {
    return !this.panel.hasChildNodes();
  },

  /**
   * Get rid of references and event listeners
   */
  destroy: function () {
    this.hide();

    for (let event of POPUP_EVENTS) {
      this.panel.removeEventListener("popup" + event,
        this["_onPopup" + event], false);
    }

    let win = this.doc.querySelector("window");
    win.removeEventListener("keypress", this._onKeyPress, false);

    let closeOnEvents = this.options.get("closeOnEvents");
    for (let {emitter, event, useCapture} of closeOnEvents) {
      for (let remove of ["removeEventListener", "off"]) {
        if (remove in emitter) {
          emitter[remove](event, this.hide, useCapture);
          break;
        }
      }
    }

    this.content = null;

    if (this._basedNode) {
      this.stopTogglingOnHover();
    }

    this.doc = null;

    this.panel.remove();
    this.panel = null;
  },

  /**
   * Show/hide the tooltip when the mouse hovers over particular nodes.
   *
   * 2 Ways to make this work:
   * - Provide a single node to attach the tooltip to, as the baseNode, and
   *   omit the second targetNodeCb argument
   * - Provide a baseNode that is the container of possibly numerous children
   *   elements that may receive a tooltip. In this case, provide the second
   *   targetNodeCb argument to decide wether or not a child should receive
   *   a tooltip.
   *
   * This works by tracking mouse movements on a base container node (baseNode)
   * and showing the tooltip when the mouse stops moving. The targetNodeCb
   * callback is used to know whether or not the particular element being
   * hovered over should indeed receive the tooltip. If you don't provide it
   * it's equivalent to a function that always returns true.
   *
   * Note that if you call this function a second time, it will itself call
   * stopTogglingOnHover before adding mouse tracking listeners again.
   *
   * @param {node} baseNode
   *        The container for all target nodes
   * @param {Function} targetNodeCb
   *        A function that accepts a node argument and returns true or false
   *        (or a promise that resolves or rejects) to signify if the tooltip
   *        should be shown on that node or not.
   *        Additionally, the function receives a second argument which is the
   *        tooltip instance itself, to be used to add/modify the content of the
   *        tooltip if needed. If omitted, the tooltip will be shown everytime.
   * @param {Number} showDelay
   *        An optional delay that will be observed before showing the tooltip.
   *        Defaults to this.defaultShowDelay.
   */
  startTogglingOnHover: function(baseNode, targetNodeCb, showDelay=this.defaultShowDelay) {
    if (this._basedNode) {
      this.stopTogglingOnHover();
    }

    this._basedNode = baseNode;
    this._showDelay = showDelay;
    this._targetNodeCb = targetNodeCb || (() => true);

    this._onBaseNodeMouseMove = this._onBaseNodeMouseMove.bind(this);
    this._onBaseNodeMouseLeave = this._onBaseNodeMouseLeave.bind(this);

    baseNode.addEventListener("mousemove", this._onBaseNodeMouseMove, false);
    baseNode.addEventListener("mouseleave", this._onBaseNodeMouseLeave, false);
  },

  /**
   * If the startTogglingOnHover function has been used previously, and you want
   * to get rid of this behavior, then call this function to remove the mouse
   * movement tracking
   */
  stopTogglingOnHover: function() {
    clearNamedTimeout(this.uid);

    this._basedNode.removeEventListener("mousemove",
      this._onBaseNodeMouseMove, false);
    this._basedNode.removeEventListener("mouseleave",
      this._onBaseNodeMouseLeave, false);

    this._basedNode = null;
    this._targetNodeCb = null;
    this._lastHovered = null;
  },

  _onBaseNodeMouseMove: function(event) {
    if (event.target !== this._lastHovered) {
      this.hide();
      this._lastHovered = event.target;
      setNamedTimeout(this.uid, this._showDelay, () => {
        this.isValidHoverTarget(event.target).then(target => {
          this.show(target);
        });
      });
    }
  },

  /**
   * Is the given target DOMNode a valid node for toggling the tooltip on hover.
   * This delegates to the user-defined _targetNodeCb callback.
   * @return a promise that resolves or rejects depending if the tooltip should
   * be shown or not. If it resolves, it does to the actual anchor to be used
   */
  isValidHoverTarget: function(target) {
    // Execute the user-defined callback which should return either true/false
    // or a promise that resolves or rejects
    let res = this._targetNodeCb(target, this);

    // The callback can additionally return a DOMNode to replace the anchor of
    // the tooltip when shown
    if (res && res.then) {
      return res.then(arg => {
        return arg instanceof Ci.nsIDOMNode ? arg : target;
      }, () => {
        return false;
      });
    } else {
      return res ? promise.resolve(res) : promise.reject(false);
    }
  },

  _onBaseNodeMouseLeave: function() {
    clearNamedTimeout(this.uid);
    this._lastHovered = null;
    this.hide();
  },

  /**
   * Set the content of this tooltip. Will first empty the tooltip and then
   * append the new content element.
   * Consider using one of the set<type>Content() functions instead.
   * @param {node} content
   *        A node that can be appended in the tooltip XUL element
   */
  set content(content) {
    if (this.content == content) {
      return;
    }

    this.empty();
    this.panel.removeAttribute("clamped-dimensions");

    if (content) {
      this.panel.appendChild(content);
    }
  },

  get content() {
    return this.panel.firstChild;
  },

  /**
   * Sets some text as the content of this tooltip.
   *
   * @param {array} messages
   *        A list of text messages.
   * @param {string} messagesClass [optional]
   *        A style class for the text messages.
   * @param {string} containerClass [optional]
   *        A style class for the text messages container.
   * @param {boolean} isAlertTooltip [optional]
   *        Pass true to add an alert image for your tooltip.
   */
  setTextContent: function(
    {
      messages,
      messagesClass,
      containerClass,
      isAlertTooltip
    },
    extraButtons = []) {
    messagesClass = messagesClass || "default-tooltip-simple-text-colors";
    containerClass = containerClass || "default-tooltip-simple-text-colors";

    let vbox = this.doc.createElement("vbox");
    vbox.className = "devtools-tooltip-simple-text-container " + containerClass;
    vbox.setAttribute("flex", "1");

    for (let text of messages) {
      let description = this.doc.createElement("description");
      description.setAttribute("flex", "1");
      description.className = "devtools-tooltip-simple-text " + messagesClass;
      description.textContent = text;
      vbox.appendChild(description);
    }

    for (let { label, className, command } of extraButtons) {
      let button = this.doc.createElement("button");
      button.className = className;
      button.setAttribute("label", label);
      button.addEventListener("command", command);
      vbox.appendChild(button);
    }

    if (isAlertTooltip) {
      let hbox = this.doc.createElement("hbox");
      hbox.setAttribute("align", "start");

      let alertImg = this.doc.createElement("image");
      alertImg.className = "devtools-tooltip-alert-icon";
      hbox.appendChild(alertImg);
      hbox.appendChild(vbox);
      this.content = hbox;
    } else {
      this.content = vbox;
    }
  },

  /**
   * Fill the tooltip with a variables view, inspecting an object via its
   * corresponding object actor, as specified in the remote debugging protocol.
   *
   * @param {object} objectActor
   *        The value grip for the object actor.
   * @param {object} viewOptions [optional]
   *        Options for the variables view visualization.
   * @param {object} controllerOptions [optional]
   *        Options for the variables view controller.
   * @param {object} relayEvents [optional]
   *        A collection of events to listen on the variables view widget.
   *        For example, { fetched: () => ... }
   * @param {boolean} reuseCachedWidget [optional]
   *        Pass false to instantiate a brand new widget for this variable.
   *        Otherwise, if a variable was previously inspected, its widget
   *        will be reused.
   * @param {Toolbox} toolbox [optional]
   *        Pass the instance of the current toolbox if you want the variables
   *        view widget to allow highlighting and selection of DOM nodes
   */
  setVariableContent: function(
    objectActor,
    viewOptions = {},
    controllerOptions = {},
    relayEvents = {},
    extraButtons = [],
    toolbox = null) {

    let vbox = this.doc.createElement("vbox");
    vbox.className = "devtools-tooltip-variables-view-box";
    vbox.setAttribute("flex", "1");

    let innerbox = this.doc.createElement("vbox");
    innerbox.className = "devtools-tooltip-variables-view-innerbox";
    innerbox.setAttribute("flex", "1");
    vbox.appendChild(innerbox);

    for (let { label, className, command } of extraButtons) {
      let button = this.doc.createElement("button");
      button.className = className;
      button.setAttribute("label", label);
      button.addEventListener("command", command);
      vbox.appendChild(button);
    }

    let widget = new VariablesView(innerbox, viewOptions);

    // If a toolbox was provided, link it to the vview
    if (toolbox) {
      widget.toolbox = toolbox;
    }

    // Analyzing state history isn't useful with transient object inspectors.
    widget.commitHierarchy = () => {};

    for (let e in relayEvents) widget.on(e, relayEvents[e]);
    VariablesViewController.attach(widget, controllerOptions);

    // Some of the view options are allowed to change between uses.
    widget.searchPlaceholder = viewOptions.searchPlaceholder;
    widget.searchEnabled = viewOptions.searchEnabled;

    // Use the object actor's grip to display it as a variable in the widget.
    // The controller options are allowed to change between uses.
    widget.controller.setSingleVariable(
      { objectActor: objectActor }, controllerOptions);

    this.content = vbox;
    this.panel.setAttribute("clamped-dimensions", "");
  },

  /**
   * Uses the provided inspectorFront's getImageDataFromURL method to resolve
   * the relative URL on the server-side, in the page context, and then sets the
   * tooltip content with the resulting image just like |setImageContent| does.
   *
   * @return a promise that resolves when the image is shown in the tooltip
   */
  setRelativeImageContent: function(imageUrl, inspectorFront, maxDim) {
    if (imageUrl.startsWith("data:")) {
      // If the imageUrl already is a data-url, save ourselves a round-trip
      this.setImageContent(imageUrl, {maxDim: maxDim});
      return promise.resolve();
    } else if (inspectorFront) {
      return inspectorFront.getImageDataFromURL(imageUrl, maxDim).then(res => {
        res.size.maxDim = maxDim;
        return res.data.string().then(str => {
          this.setImageContent(str, res.size);
        });
      }, () => {
        this.setBrokenImageContent();
      });
    }
    return promise.resolve();
  },

  /**
   * Fill the tooltip with a message explaining the the image is missing
   */
  setBrokenImageContent: function() {
    this.setTextContent({
      messages: [l10n.strings.GetStringFromName("previewTooltip.image.brokenImage")]
    });
  },

  /**
   * Fill the tooltip with an image and add the image dimension at the bottom.
   *
   * Only use this for absolute URLs that can be queried from the devtools
   * client-side. For relative URLs, use |setRelativeImageContent|.
   *
   * @param {string} imageUrl
   *        The url to load the image from
   * @param {Object} options
   *        The following options are supported:
   *        - resized : whether or not the image identified by imageUrl has been
   *        resized before this function was called.
   *        - naturalWidth/naturalHeight : the original size of the image before
   *        it was resized, if if was resized before this function was called.
   *        If not provided, will be measured on the loaded image.
   *        - maxDim : if the image should be resized before being shown, pass
   *        a number here
   */
  setImageContent: function(imageUrl, options={}) {
    if (!imageUrl) {
      return;
    }

    // Main container
    let vbox = this.doc.createElement("vbox");
    vbox.setAttribute("align", "center");

    // Display the image
    let image = this.doc.createElement("image");
    image.setAttribute("src", imageUrl);
    if (options.maxDim) {
      image.style.maxWidth = options.maxDim + "px";
      image.style.maxHeight = options.maxDim + "px";
    }
    vbox.appendChild(image);

    // Dimension label
    let label = this.doc.createElement("label");
    label.classList.add("devtools-tooltip-caption");
    label.classList.add("theme-comment");
    if (options.naturalWidth && options.naturalHeight) {
      label.textContent = this._getImageDimensionLabel(options.naturalWidth,
        options.naturalHeight);
    } else {
      // If no dimensions were provided, load the image to get them
      label.textContent = l10n.strings.GetStringFromName("previewTooltip.image.brokenImage");
      let imgObj = new this.doc.defaultView.Image();
      imgObj.src = imageUrl;
      imgObj.onload = () => {
        imgObj.onload = null;
        label.textContent = this._getImageDimensionLabel(imgObj.naturalWidth,
          imgObj.naturalHeight);
      }
    }
    vbox.appendChild(label);

    this.content = vbox;
  },

  _getImageDimensionLabel: (w, h) => w + " x " + h,

  /**
   * Fill the tooltip with a new instance of the spectrum color picker widget
   * initialized with the given color, and return a promise that resolves to
   * the instance of spectrum
   */
  setColorPickerContent: function(color) {
    let def = promise.defer();

    // Create an iframe to contain spectrum
    let iframe = this.doc.createElementNS(XHTML_NS, "iframe");
    iframe.setAttribute("transparent", true);
    iframe.setAttribute("width", "210");
    iframe.setAttribute("height", "195");
    iframe.setAttribute("flex", "1");
    iframe.setAttribute("class", "devtools-tooltip-iframe");

    let panel = this.panel;
    let xulWin = this.doc.ownerGlobal;

    // Wait for the load to initialize spectrum
    function onLoad() {
      iframe.removeEventListener("load", onLoad, true);
      let win = iframe.contentWindow.wrappedJSObject;

      let container = win.document.getElementById("spectrum");
      let spectrum = new Spectrum(container, color);

      // Finalize spectrum's init when the tooltip becomes visible
      panel.addEventListener("popupshown", function shown() {
        panel.removeEventListener("popupshown", shown, true);
        spectrum.show();
        def.resolve(spectrum);
      }, true);
    }
    iframe.addEventListener("load", onLoad, true);
    iframe.setAttribute("src", SPECTRUM_FRAME);

    // Put the iframe in the tooltip
    this.content = iframe;

    return def.promise;
  },

  /**
   * Set the content of the tooltip to be the result of CSSTransformPreviewer.
   * Meaning a canvas previewing a css transformation.
   *
   * @param {String} transform
   *        The CSS transform value (e.g. "rotate(45deg) translateX(50px)")
   * @param {PageStyleActor} pageStyle
   *        An instance of the PageStyleActor that will be used to retrieve
   *        computed styles
   * @param {NodeActor} node
   *        The NodeActor for the currently selected node
   * @return A promise that resolves when the tooltip content is ready, or
   *         rejects if no transform is provided or is invalid
   */
  setCssTransformContent: function(transform, pageStyle, node) {
    let def = promise.defer();

    if (transform) {
      // Look into the computed styles to find the width and height and possibly
      // the origin if it hadn't been provided
      pageStyle.getComputed(node, {
        filter: "user",
        markMatched: false,
        onlyMatched: false
      }).then(styles => {
        let origin = styles["transform-origin"].value;
        let width = parseInt(styles["width"].value);
        let height = parseInt(styles["height"].value);

        let root = this.doc.createElementNS(XHTML_NS, "div");
        let previewer = new CSSTransformPreviewer(root);
        this.content = root;
        if (!previewer.preview(transform, origin, width, height)) {
          def.reject();
        } else {
          def.resolve();
        }
      });
    } else {
      def.reject();
    }

    return def.promise;
  },

  /**
   * Set the content of the tooltip to display a font family preview.
   * This is based on Lea Verou's Dablet. See https://github.com/LeaVerou/dabblet
   * for more info.
   *
   * @param {String} font
   *        The font family value.
   */
  setFontFamilyContent: function(font) {
    let def = promise.defer();

    if (font) {
      // Main container
      let vbox = this.doc.createElement("vbox");
      vbox.setAttribute("flex", "1");

      // Display the font family previewer
      let previewer = this.doc.createElement("description");
      previewer.setAttribute("flex", "1");
      previewer.style.fontFamily = font;
      previewer.classList.add("devtools-tooltip-font-previewer-text");
      previewer.textContent = "(ABCabc123&@%)";
      vbox.appendChild(previewer);

      this.content = vbox;

      def.resolve();
    } else {
      def.reject();
    }

    return def.promise;
  }
};

/**
 * Base class for all (color, gradient, ...)-swatch based value editors inside
 * tooltips
 *
 * @param {XULDocument} doc
 */
function SwatchBasedEditorTooltip(doc) {
  // Creating a tooltip instance
  // This one will consume outside clicks as it makes more sense to let the user
  // close the tooltip by clicking out
  // It will also close on <escape> and <enter>
  this.tooltip = new Tooltip(doc, {
    consumeOutsideClick: true,
    closeOnKeys: [ESCAPE_KEYCODE, RETURN_KEYCODE],
    noAutoFocus: false
  });

  // By default, swatch-based editor tooltips revert value change on <esc> and
  // commit value change on <enter>
  this._onTooltipKeypress = (event, code) => {
    if (code === ESCAPE_KEYCODE) {
      this.revert();
    } else if (code === RETURN_KEYCODE) {
      this.commit();
    }
  };
  this.tooltip.on("keypress", this._onTooltipKeypress);

  // All target swatches are kept in a map, indexed by swatch DOM elements
  this.swatches = new Map();

  // When a swatch is clicked, and for as long as the tooltip is shown, the
  // activeSwatch property will hold the reference to the swatch DOM element
  // that was clicked
  this.activeSwatch = null;

  this._onSwatchClick = this._onSwatchClick.bind(this);
}

SwatchBasedEditorTooltip.prototype = {
  show: function() {
    if (this.activeSwatch) {
      this.tooltip.show(this.activeSwatch, "topcenter bottomleft");
    }
  },

  hide: function() {
    this.tooltip.hide();
  },

  /**
   * Add a new swatch DOM element to the list of swatch elements this editor
   * tooltip knows about. That means from now on, clicking on that swatch will
   * toggle the editor.
   *
   * @param {node} swatchEl
   *        The element to add
   * @param {object} callbacks
   *        Callbacks that will be executed when the editor wants to preview a
   *        value change, or revert a change, or commit a change.
   * @param {object} originalValue
   *        The original value before the editor in the tooltip makes changes
   *        This can be of any type, and will be passed, as is, in the revert
   *        callback
   */
  addSwatch: function(swatchEl, callbacks={}, originalValue) {
    if (!callbacks.onPreview) callbacks.onPreview = function() {};
    if (!callbacks.onRevert) callbacks.onRevert = function() {};
    if (!callbacks.onCommit) callbacks.onCommit = function() {};

    this.swatches.set(swatchEl, {
      callbacks: callbacks,
      originalValue: originalValue
    });
    swatchEl.addEventListener("click", this._onSwatchClick, false);
  },

  removeSwatch: function(swatchEl) {
    if (this.swatches.has(swatchEl)) {
      if (this.activeSwatch === swatchEl) {
        this.hide();
        this.activeSwatch = null;
      }
      swatchEl.removeEventListener("click", this._onSwatchClick, false);
      this.swatches.delete(swatchEl);
    }
  },

  _onSwatchClick: function(event) {
    let swatch = this.swatches.get(event.target);
    if (swatch) {
      this.activeSwatch = event.target;
      this.show();
      event.stopPropagation();
    }
  },

  /**
   * Not called by this parent class, needs to be taken care of by sub-classes
   */
  preview: function(value) {
    if (this.activeSwatch) {
      let swatch = this.swatches.get(this.activeSwatch);
      swatch.callbacks.onPreview(value);
    }
  },

  /**
   * This parent class only calls this on <esc> keypress
   */
  revert: function() {
    if (this.activeSwatch) {
      let swatch = this.swatches.get(this.activeSwatch);
      swatch.callbacks.onRevert(swatch.originalValue);
    }
  },

  /**
   * This parent class only calls this on <enter> keypress
   */
  commit: function() {
    if (this.activeSwatch) {
      let swatch = this.swatches.get(this.activeSwatch);
      swatch.callbacks.onCommit();
    }
  },

  destroy: function() {
    this.swatches.clear();
    this.activeSwatch = null;
    this.tooltip.off("keypress", this._onTooltipKeypress);
    this.tooltip.destroy();
  }
};

/**
 * The swatch color picker tooltip class is a specific class meant to be used
 * along with output-parser's generated color swatches.
 * It extends the parent SwatchBasedEditorTooltip class.
 * It just wraps a standard Tooltip and sets its content with an instance of a
 * color picker.
 *
 * @param {XULDocument} doc
 */
function SwatchColorPickerTooltip(doc) {
  SwatchBasedEditorTooltip.call(this, doc);

  // Creating a spectrum instance. this.spectrum will always be a promise that
  // resolves to the spectrum instance
  this.spectrum = this.tooltip.setColorPickerContent([0, 0, 0, 1]);
  this._onSpectrumColorChange = this._onSpectrumColorChange.bind(this);
}

module.exports.SwatchColorPickerTooltip = SwatchColorPickerTooltip;

SwatchColorPickerTooltip.prototype = Heritage.extend(SwatchBasedEditorTooltip.prototype, {
  /**
   * Overriding the SwatchBasedEditorTooltip.show function to set spectrum's
   * color.
   */
  show: function() {
    // Call then parent class' show function
    SwatchBasedEditorTooltip.prototype.show.call(this);
    // Then set spectrum's color and listen to color changes to preview them
    if (this.activeSwatch) {
      let swatch = this.swatches.get(this.activeSwatch);
      let color = this.activeSwatch.style.backgroundColor;
      this.spectrum.then(spectrum => {
        spectrum.off("changed", this._onSpectrumColorChange);
        spectrum.rgb = this._colorToRgba(color);
        spectrum.on("changed", this._onSpectrumColorChange);
        spectrum.updateUI();
      });
    }
  },

  _onSpectrumColorChange: function(event, rgba, cssColor) {
    if (this.activeSwatch) {
      this.activeSwatch.style.backgroundColor = cssColor;
      this.activeSwatch.nextSibling.textContent = cssColor;
      this.preview(cssColor);
    }
  },

  _colorToRgba: function(color) {
    color = new colorUtils.CssColor(color);
    let rgba = color._getRGBATuple();
    return [rgba.r, rgba.g, rgba.b, rgba.a];
  },

  destroy: function() {
    SwatchBasedEditorTooltip.prototype.destroy.call(this);
    this.spectrum.then(spectrum => {
      spectrum.off("changed", this._onSpectrumColorChange);
      spectrum.destroy();
    });
  }
});

/**
 * Internal util, checks whether a css declaration is a gradient
 */
function isGradientRule(property, value) {
  return (property === "background" || property === "background-image") &&
    value.match(GRADIENT_RE);
}

/**
 * Internal util, checks whether a css declaration is a color
 */
function isColorOnly(property, value) {
  return property === "background-color" ||
         property === "color" ||
         property.match(BORDERCOLOR_RE);
}

/**
 * L10N utility class
 */
function L10N() {}
L10N.prototype = {};

let l10n = new L10N();

loader.lazyGetter(L10N.prototype, "strings", () => {
  return Services.strings.createBundle(
    "chrome://browser/locale/devtools/inspector.properties");
});