chrome/browser/resources/file_manager/foreground/js/ui/progress_center_panel.js

// Copyright 2013 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

'use strict';

/**
 * Progress center panel.
 *
 * @param {HTMLElement} element DOM Element of the process center panel.
 * @param {function(string)} cancelCallback Callback to becalled with the ID of
 *     the progress item when the cancel button is clicked.
 * @constructor
 */
var ProgressCenterPanel = function(element, cancelCallback) {
  this.element_ = element;
  this.openView_ = this.element_.querySelector('#progress-center-open-view');
  this.closeView_ = this.element_.querySelector('#progress-center-close-view');
  this.cancelCallback_ = cancelCallback;

  /**
   * Reset is requested but it is pending until the transition of progress bar
   * is complete.
   * @type {boolean}
   * @private
   */
  this.resetRequested_ = false;

  /**
   * Only progress item in the close view.
   * @type {!HTMLElement}
   * @private
   */
  this.closeViewItem_ = this.closeView_.querySelector('li');

  Object.seal(this);

  // Register event handlers.
  element.addEventListener('click', this.onClick_.bind(this));
  element.addEventListener(
      'webkitTransitionEnd', this.onItemTransitionEnd_.bind(this));
};

/**
 * Whether to use the new progress center UI or not.
 * TODO(hirono): Remove the flag after replacing the old butter bar with the new
 * progress center.
 * @type {boolean}
 * @private
 */
ProgressCenterPanel.ENABLED_ = true;

/**
 * Updates attributes of the item element.
 * @param {!HTMLElement} element Element to be updated.
 * @param {!ProgressCenterItem} item Progress center item.
 * @private
 */
ProgressCenterPanel.updateItemElement_ = function(element, item) {
  // Sets element attributes.
  element.setAttribute('data-progress-id', item.id);
  element.setAttribute('data-progress-max', item.progressMax);
  element.setAttribute('data-progress-value', item.progressValue);
  element.className = '';
  if (item.state === ProgressItemState.ERROR)
    element.classList.add('error');
  if (item.cancelable)
    element.classList.add('cancelable');

  // If the transition animation is needed, apply it.
  var previousWidthRate =
      parseInt(element.querySelector('.progress-track').style.width);
  if (item.state === ProgressItemState.COMPLETE &&
      previousWidthRate !== item.progressRateByPercent) {
    // The attribute pre-complete means that the actual operation is already
    // done but the UI transition of progress bar is not complete.
    element.setAttribute('pre-complete', '');
  } else {
    element.querySelector('label').textContent = item.message;
  }

  // To commit the property change and to trigger the transition even if the
  // change is done synchronously, assign the width value asynchronously.
  setTimeout(function() {
    var track = element.querySelector('.progress-track');
    // When the progress rate is reverted, we does not use the transition
    // animation. Specifying '0' overrides the CSS settings and specifying null
    // re-enables it.
    track.style.transitionDuration =
        previousWidthRate > item.progressRateByPercent ? '0' : null;
    track.style.width = item.progressRateByPercent + '%';
  }, 0);
};

/**
 * Updates an item to the progress center panel.
 * @param {!ProgressCenterItem} item Item including new contents.
 * @param {!ProgressCenterItem} summarizedItem Item to be desplayed in the close
 *     view.
 */
ProgressCenterPanel.prototype.updateItem = function(item, summarizedItem) {
  // If reset is requested, force to reset.
  if (this.resetRequested_)
    this.reset(true);

  // Update the item.
  var itemElement = this.getItemElement_(item.id);
  var removed = false;

  // Check whether the item should be displayed or not by referring its state.
  switch (item.state) {
    // Should show the item.
    case ProgressItemState.PROGRESSING:
    case ProgressItemState.ERROR:
      // If the item has not been added yet, create a new element and add it.
      if (!itemElement) {
        itemElement = this.createNewItemElement_();
        this.openView_.insertBefore(itemElement, this.openView_.firstNode);
      }

      // Update the element by referring the item model.
      ProgressCenterPanel.updateItemElement_(itemElement, item);
      this.element_.hidden = false;
      break;

    // Should not show the item.
    case ProgressItemState.COMPLETE:
    case ProgressItemState.CANCELED:
      // If itemElement is not shown, just break.
      if (!itemElement)
        break;

      // If the item is complete state, once update it because it may turn to
      // have the pre-complete attribute.
      if (item.state == ProgressItemState.COMPLETE)
        ProgressCenterPanel.updateItemElement_(itemElement, item);

      // If the item has the pre-complete attribute, keep showing it. Otherwise,
      // just remove it.
      if (item.state !== ProgressItemState.COMPLETE ||
          !itemElement.hasAttribute('pre-complete')) {
        this.openView_.removeChild(itemElement);
      }
      break;
  }

  // Update close view.
  this.closeView_.classList.toggle('single', !summarizedItem.summarized);
  ProgressCenterPanel.updateItemElement_(this.closeViewItem_, summarizedItem);
};

/**
 * Remove all the items.
 * @param {boolean=} opt_force True if we force to reset and do not wait the
 *    transition of progress bar. False otherwise. False is default.
 */
ProgressCenterPanel.prototype.reset = function(opt_force) {
  if (!opt_force && this.element_.querySelector('[pre-complete]')) {
    this.resetRequested_ = true;
    return;
  }

  // Clear the flag.
  this.resetRequested_ = false;

  // Clear the all compete item.
  this.openView_.innerHTML = '';

  // Hide the progress center.
  this.element_.hidden = true;
  this.element_.classList.remove('opened');
};

/**
 * Gets an item element having the specified ID.
 * @param {string} id progress item ID.
 * @return {HTMLElement} Item element having the ID.
 * @private
 */
ProgressCenterPanel.prototype.getItemElement_ = function(id) {
  var query = 'li[data-progress-id="' + id + '"]';
  return this.openView_.querySelector(query);
};

/**
 * Creates an item element.
 * @return {HTMLElement} Created item element.
 * @private
 */
ProgressCenterPanel.prototype.createNewItemElement_ = function() {
  var label = this.element_.ownerDocument.createElement('label');
  label.className = 'label';

  var progressBarIndicator = this.element_.ownerDocument.createElement('div');
  progressBarIndicator.className = 'progress-track';

  var progressBar = this.element_.ownerDocument.createElement('div');
  progressBar.className = 'progress-bar';
  progressBar.appendChild(progressBarIndicator);

  var cancelButton = this.element_.ownerDocument.createElement('button');
  cancelButton.className = 'cancel';
  cancelButton.setAttribute('tabindex', '-1');

  var progressFrame = this.element_.ownerDocument.createElement('div');
  progressFrame.className = 'progress-frame';
  progressFrame.appendChild(progressBar);
  progressFrame.appendChild(cancelButton);

  var itemElement = this.element_.ownerDocument.createElement('li');
  itemElement.appendChild(label);
  itemElement.appendChild(progressFrame);

  return itemElement;
};

/**
 * Handles the transition end event of items.
 * @param {Event} event Transition end event.
 * @private
 */
ProgressCenterPanel.prototype.onItemTransitionEnd_ = function(event) {
  var itemElement = event.target.parentNode.parentNode.parentNode;
  if (!itemElement.hasAttribute('pre-complete') ||
      event.propertyName !== 'width')
    return;
  if (itemElement !== this.closeViewItem_)
    this.openView_.removeChild(itemElement);
  else
    itemElement.removeAttribute('pre-complete');
  if (this.resetRequested_)
    this.reset();
};

/**
 * Handles the click event.
 * @param {Event} event Click event.
 * @private
 */
ProgressCenterPanel.prototype.onClick_ = function(event) {
  if (event.target.classList.contains('toggle') &&
      !this.closeView_.classList.contains('single'))
    this.element_.classList.toggle('opened');
  else if ((event.target.classList.contains('toggle') &&
            this.closeView_.classList.contains('single')) ||
           event.target.classList.contains('cancel'))
    this.cancelCallback_(
        event.target.parentNode.parentNode.getAttribute('data-progress-id'));
};