/* 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";

// This is loaded into chrome windows with the subscript loader. If you need to
// define globals, wrap in a block to prevent leaking onto `window`.
{
  const { Services } = ChromeUtils.import(
    "resource://gre/modules/Services.jsm"
  );

  MozElements.NotificationBox = class NotificationBox {
    /**
     * Creates a new class to handle a notification box, but does not add any
     * elements to the DOM until a notification has to be displayed.
     *
     * @param insertElementFn
     *        Called with the "notification-stack" element as an argument when the
     *        first notification has to be displayed.
     */
    constructor(insertElementFn) {
      this._insertElementFn = insertElementFn;
      this._animating = false;
      this.currentNotification = null;
    }

    get stack() {
      if (!this._stack) {
        let stack = document.createXULElement("legacy-stack");
        stack._notificationBox = this;
        stack.className = "notificationbox-stack";
        stack.appendChild(document.createXULElement("spacer"));
        stack.addEventListener("transitionend", event => {
          if (
            event.target.localName == "notification" &&
            event.propertyName == "margin-top"
          ) {
            this._finishAnimation();
          }
        });
        this._insertElementFn(stack);
        this._stack = stack;
      }
      return this._stack;
    }

    get _allowAnimation() {
      return window.matchMedia("(prefers-reduced-motion: no-preference)")
        .matches;
    }

    get allNotifications() {
      // Don't create any DOM if no new notification has been added yet.
      if (!this._stack) {
        return [];
      }

      var closedNotification = this._closedNotification;
      var notifications = this.stack.getElementsByTagName("notification");
      return Array.prototype.filter.call(
        notifications,
        n => n != closedNotification
      );
    }

    getNotificationWithValue(aValue) {
      var notifications = this.allNotifications;
      for (var n = notifications.length - 1; n >= 0; n--) {
        if (aValue == notifications[n].getAttribute("value")) {
          return notifications[n];
        }
      }
      return null;
    }

    /**
     * Creates a <notification> element and shows it. The calling code can modify
     * the element synchronously to add features to the notification.
     *
     * @param aLabel
     *        The main message text, or a DocumentFragment containing elements to
     *        add as children of the notification's main <description> element.
     * @param aValue
     *        String identifier of the notification.
     * @param aImage
     *        URL of the icon image to display. If not specified, a default icon
     *        based on the priority will be shown.
     * @param aPriority
     *        One of the PRIORITY_ constants. These determine the appearance of
     *        the notification based on severity (using the "type" attribute), and
     *        only the notification with the highest priority is displayed.
     * @param aButtons
     *        Array of objects defining action buttons:
     *        {
     *          label:
     *            Label of the <button> element.
     *          accessKey:
     *            Access key character for the <button> element.
     *          "l10n-id"
     *            Localization id for the <button>, to be used instead of
     *            specifying a separate label and access key.
     *          callback:
     *            When the button is used, this is called with the arguments:
     *             1. The <notification> element.
     *             2. This button object definition.
     *             3. The <button> element.
     *             4. The "command" event.
     *          popup:
     *            If specified, the button will open the popup element with this
     *            ID, anchored to the button. This is alternative to "callback".
     *          is:
     *            Defines a Custom Element name to use as the "is" value on
     *            button creation.
     *        }
     * @param aEventCallback
     *        This may be called with the "removed", "dismissed" or "disconnected"
     *        parameter:
     *          removed - notification has been removed
     *          dismissed - user dismissed notification
     *          disconnected - notification removed in any way
     * @param aNotificationIs
     *        Defines a Custom Element name to use as the "is" value on creation.
     *        This allows subclassing the created element.
     *
     * @return The <notification> element that is shown.
     */
    appendNotification(
      aLabel,
      aValue,
      aImage,
      aPriority,
      aButtons,
      aEventCallback,
      aNotificationIs
    ) {
      if (
        aPriority < this.PRIORITY_INFO_LOW ||
        aPriority > this.PRIORITY_CRITICAL_HIGH
      ) {
        throw new Error("Invalid notification priority " + aPriority);
      }

      // check for where the notification should be inserted according to
      // priority. If two are equal, the existing one appears on top.
      var notifications = this.allNotifications;
      var insertPos = null;
      for (var n = notifications.length - 1; n >= 0; n--) {
        if (notifications[n].priority < aPriority) {
          break;
        }
        insertPos = notifications[n];
      }

      // Create the Custom Element and connect it to the document immediately.
      var newitem = document.createXULElement(
        "notification",
        aNotificationIs ? { is: aNotificationIs } : {}
      );
      this.stack.insertBefore(newitem, insertPos);

      // Custom notification classes may not have the messageText property.
      if (newitem.messageText) {
        // Can't use instanceof in case this was created from a different document:
        if (
          aLabel &&
          typeof aLabel == "object" &&
          aLabel.nodeType &&
          aLabel.nodeType == aLabel.DOCUMENT_FRAGMENT_NODE
        ) {
          newitem.messageText.appendChild(aLabel);
        } else {
          newitem.messageText.textContent = aLabel;
        }
      }
      newitem.setAttribute("value", aValue);
      if (aImage) {
        newitem.messageImage.setAttribute("src", aImage);
      }
      newitem.eventCallback = aEventCallback;

      if (aButtons) {
        for (var b = 0; b < aButtons.length; b++) {
          var button = aButtons[b];
          var buttonElem = document.createXULElement(
            "button",
            button.is ? { is: button.is } : {}
          );

          if (button["l10n-id"]) {
            buttonElem.setAttribute("data-l10n-id", button["l10n-id"]);
          } else {
            buttonElem.setAttribute("label", button.label);
            if (typeof button.accessKey == "string") {
              buttonElem.setAttribute("accesskey", button.accessKey);
            }
          }

          buttonElem.classList.add("notification-button");
          if (button.primary) {
            buttonElem.classList.add("primary");
          }

          newitem.messageDetails.appendChild(buttonElem);
          buttonElem.buttonInfo = button;
        }
      }

      newitem.priority = aPriority;
      if (aPriority >= this.PRIORITY_CRITICAL_LOW) {
        newitem.setAttribute("type", "critical");
      } else if (aPriority <= this.PRIORITY_INFO_HIGH) {
        newitem.setAttribute("type", "info");
      } else {
        newitem.setAttribute("type", "warning");
      }

      if (!insertPos) {
        newitem.style.display = "block";
        newitem.style.position = "fixed";
        newitem.style.top = "100%";
        newitem.style.marginTop = "-15px";
        newitem.style.opacity = "0";
        this._showNotification(newitem, true);
      }

      // Fire event for accessibility APIs
      var event = document.createEvent("Events");
      event.initEvent("AlertActive", true, true);
      newitem.dispatchEvent(event);

      return newitem;
    }

    removeNotification(aItem, aSkipAnimation) {
      if (!aItem.parentNode) {
        return;
      }
      if (aItem == this.currentNotification) {
        this.removeCurrentNotification(aSkipAnimation);
      } else if (aItem != this._closedNotification) {
        this._removeNotificationElement(aItem);
      }
    }

    _removeNotificationElement(aChild) {
      if (aChild.eventCallback) {
        aChild.eventCallback("removed");
      }
      this.stack.removeChild(aChild);

      // make sure focus doesn't get lost (workaround for bug 570835)
      if (!Services.focus.getFocusedElementForWindow(window, false, {})) {
        Services.focus.moveFocus(
          window,
          this.stack,
          Services.focus.MOVEFOCUS_FORWARD,
          0
        );
      }
    }

    removeCurrentNotification(aSkipAnimation) {
      this._showNotification(this.currentNotification, false, aSkipAnimation);
    }

    removeAllNotifications(aImmediate) {
      var notifications = this.allNotifications;
      for (var n = notifications.length - 1; n >= 0; n--) {
        if (aImmediate) {
          this._removeNotificationElement(notifications[n]);
        } else {
          this.removeNotification(notifications[n]);
        }
      }
      this.currentNotification = null;

      // Clean up any currently-animating notification; this is necessary
      // if a notification was just opened and is still animating, but we
      // want to close it *without* animating.  This can even happen if
      // animations get disabled (via prefers-reduced-motion) and this method
      // is called immediately after an animated notification was displayed
      // (although this case isn't very likely).
      if (aImmediate || !this._allowAnimation) {
        this._finishAnimation();
      }
    }

    removeTransientNotifications() {
      var notifications = this.allNotifications;
      for (var n = notifications.length - 1; n >= 0; n--) {
        var notification = notifications[n];
        if (notification.persistence) {
          notification.persistence--;
        } else if (Date.now() > notification.timeout) {
          this.removeNotification(notification, true);
        }
      }
    }

    _showNotification(aNotification, aSlideIn, aSkipAnimation) {
      this._finishAnimation();

      var height = aNotification.getBoundingClientRect().height;
      var skipAnimation =
        aSkipAnimation || height == 0 || !this._allowAnimation;
      aNotification.classList.toggle("animated", !skipAnimation);

      if (aSlideIn) {
        this.currentNotification = aNotification;
        aNotification.style.removeProperty("display");
        aNotification.style.removeProperty("position");
        aNotification.style.removeProperty("top");
        aNotification.style.removeProperty("margin-top");
        aNotification.style.removeProperty("opacity");

        if (skipAnimation) {
          return;
        }
      } else {
        this._closedNotification = aNotification;
        var notifications = this.allNotifications;
        var idx = notifications.length - 1;
        this.currentNotification = idx >= 0 ? notifications[idx] : null;

        if (skipAnimation) {
          this._removeNotificationElement(this._closedNotification);
          delete this._closedNotification;
          return;
        }

        aNotification.style.marginTop = -height + "px";
        aNotification.style.opacity = 0;
      }

      this._animating = true;
    }

    _finishAnimation() {
      if (this._animating) {
        this._animating = false;
        if (this._closedNotification) {
          this._removeNotificationElement(this._closedNotification);
          delete this._closedNotification;
        }
      }
    }
  };

  // These are defined on the instance prototype for backwards compatibility.
  Object.assign(MozElements.NotificationBox.prototype, {
    PRIORITY_INFO_LOW: 1,
    PRIORITY_INFO_MEDIUM: 2,
    PRIORITY_INFO_HIGH: 3,
    PRIORITY_WARNING_LOW: 4,
    PRIORITY_WARNING_MEDIUM: 5,
    PRIORITY_WARNING_HIGH: 6,
    PRIORITY_CRITICAL_LOW: 7,
    PRIORITY_CRITICAL_MEDIUM: 8,
    PRIORITY_CRITICAL_HIGH: 9,
  });

  MozElements.Notification = class Notification extends MozXULElement {
    static get markup() {
      return `
      <hbox class="messageDetails" align="center" flex="1"
            oncommand="this.parentNode._doButtonCommand(event);">
        <image class="messageImage"/>
        <description class="messageText" flex="1"/>
        <spacer flex="1"/>
      </hbox>
      <toolbarbutton ondblclick="event.stopPropagation();"
                     class="messageCloseButton close-icon tabbable"
                     tooltiptext="&closeNotification.tooltip;"
                     oncommand="this.parentNode.dismiss();"/>
      `;
    }

    static get entities() {
      return ["chrome://global/locale/notification.dtd"];
    }

    constructor() {
      super();
      this.persistence = 0;
      this.priority = 0;
      this.timeout = 0;
    }

    connectedCallback() {
      this.appendChild(this.constructor.fragment);

      for (let [propertyName, selector] of [
        ["messageDetails", ".messageDetails"],
        ["messageImage", ".messageImage"],
        ["messageText", ".messageText"],
        ["spacer", "spacer"],
      ]) {
        this[propertyName] = this.querySelector(selector);
      }
    }

    disconnectedCallback() {
      if (this.eventCallback) {
        this.eventCallback("disconnected");
      }
    }

    get control() {
      return this.closest(".notificationbox-stack")._notificationBox;
    }

    /**
     * Changes the text of an existing notification. If the notification was
     * created with a custom fragment, it will be overwritten with plain text.
     */
    set label(value) {
      this.messageText.textContent = value;
    }

    /**
     * This method should only be called when the user has manually closed the
     * notification. If you want to programmatically close the notification, you
     * should call close() instead.
     */
    dismiss() {
      if (this.eventCallback) {
        this.eventCallback("dismissed");
      }
      this.close();
    }

    close() {
      if (!this.parentNode) {
        return;
      }
      this.control.removeNotification(this);
    }

    _doButtonCommand(event) {
      if (!("buttonInfo" in event.target)) {
        return;
      }

      var button = event.target.buttonInfo;
      if (button.popup) {
        document
          .getElementById(button.popup)
          .openPopup(
            event.originalTarget,
            "after_start",
            0,
            0,
            false,
            false,
            event
          );
        event.stopPropagation();
      } else {
        var callback = button.callback;
        if (callback) {
          var result = callback(this, button, event.target, event);
          if (!result) {
            this.close();
          }
          event.stopPropagation();
        }
      }
    }
  };

  customElements.define("notification", MozElements.Notification);
}