[Files.app] Split the JavaScript files into subdirectories: common, background, and foreground

chrome/browser/resources/file_manager/js/drag_selector.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';
-
-/**
- * Drag selector used on the file list or the grid table.
- * TODO(hirono): Support drag selection for grid view. crbug.com/224832
- * @constructor
- */
-function DragSelector() {
-  /**
-   * Target list of drag selection.
-   * @type {cr.ui.List}
-   * @private
-   */
-  this.target_ = null;
-
-  /**
-   * Border element of drag handle.
-   * @type {HtmlElement}
-   * @private
-   */
-  this.border_ = null;
-
-  /**
-   * Start point of dragging.
-   * @type {number?}
-   * @private
-   */
-  this.startX_ = null;
-
-  /**
-   * Start point of dragging.
-   * @type {number?}
-   * @private
-   */
-  this.startY_ = null;
-
-  /**
-   * Indexes of selected items by dragging at the last update.
-   * @type {Array.<number>!}
-   * @private
-   */
-  this.lastSelection_ = [];
-
-  /**
-   * Indexes of selected items at the start of dragging.
-   * @type {Array.<number>!}
-   * @private
-   */
-  this.originalSelection_ = [];
-
-  // Bind handlers to make them removable.
-  this.onMouseMoveBound_ = this.onMouseMove_.bind(this);
-  this.onMouseUpBound_ = this.onMouseUp_.bind(this);
-
-  Object.seal(this);
-}
-
-/**
- * Flag that shows whether the item is included in the selection or not.
- * @enum {number}
- * @private
- */
-DragSelector.SelectionFlag_ = {
-  IN_LAST_SELECTION: 1 << 0,
-  IN_CURRENT_SELECTION: 1 << 1
-};
-
-/**
- * Obtains the scrolled position in the element of mouse pointer from the mouse
- * event.
- *
- * @param {HTMLElement} element Element that has the scroll bars.
- * @param {Event} event The mouse event.
- * @return {object} Scrolled position.
- */
-DragSelector.getScrolledPosition = function(element, event) {
-  if (!element.cachedBounds) {
-    element.cachedBounds = element.getBoundingClientRect();
-    if (!element.cachedBounds)
-      return null;
-  }
-  var rect = element.cachedBounds;
-  return {
-    x: event.clientX - rect.left + element.scrollLeft,
-    y: event.clientY - rect.top + element.scrollTop
-  };
-};
-
-/**
- * Starts drag selection by reacting dragstart event.
- * This function must be called from handlers of dragstart event.
- *
- * @this {DragSelector}
- * @param {cr.ui.List} list List where the drag selection starts.
- * @param {Event} event The dragstart event.
- */
-DragSelector.prototype.startDragSelection = function(list, event) {
-  // Precondition check
-  if (!list.selectionModel_.multiple || this.target_)
-    return;
-
-  // Set the target of the drag selection
-  this.target_ = list;
-
-  // Prevent the default action.
-  event.preventDefault();
-
-  // Save the start state.
-  var startPos = DragSelector.getScrolledPosition(list, event);
-  if (!startPos)
-    return;
-  this.startX_ = startPos.x;
-  this.startY_ = startPos.y;
-  this.lastSelection_ = [];
-  this.originalSelection_ = this.target_.selectionModel_.selectedIndexes;
-
-  // Create and add the border element
-  if (!this.border_) {
-    this.border_ = this.target_.ownerDocument.createElement('div');
-    this.border_.className = 'drag-selection-border';
-  }
-  this.border_.style.left = this.startX_ + 'px';
-  this.border_.style.top = this.startY_ + 'px';
-  this.border_.style.width = '0';
-  this.border_.style.height = '0';
-  list.appendChild(this.border_);
-
-  // If no modifier key is pressed, clear the original selection.
-  if (!event.shiftKey && !event.ctrlKey)
-    this.target_.selectionModel_.unselectAll();
-
-  // Register event handlers.
-  // The handlers are bounded at the constructor.
-  this.target_.ownerDocument.addEventListener(
-      'mousemove', this.onMouseMoveBound_, true);
-  this.target_.ownerDocument.addEventListener(
-      'mouseup', this.onMouseUpBound_, true);
-};
-
-/**
- * Handles the mousemove event.
- * @private
- * @param {MouseEvent} event The mousemove event.
- */
-DragSelector.prototype.onMouseMove_ = function(event) {
-  // Get the selection bounds.
-  var pos = DragSelector.getScrolledPosition(this.target_, event);
-  var borderBounds = {
-    left: Math.max(Math.min(this.startX_, pos.x), 0),
-    top: Math.max(Math.min(this.startY_, pos.y), 0),
-    right: Math.min(Math.max(this.startX_, pos.x), this.target_.scrollWidth),
-    bottom: Math.min(Math.max(this.startY_, pos.y), this.target_.scrollHeight)
-  };
-  borderBounds.width = borderBounds.right - borderBounds.left;
-  borderBounds.height = borderBounds.bottom - borderBounds.top;
-
-  // Collect items within the selection rect.
-  var currentSelection = this.target_.getHitElements(
-      borderBounds.left,
-      borderBounds.top,
-      borderBounds.width,
-      borderBounds.height);
-  var pointedElements = this.target_.getHitElements(pos.x, pos.y);
-  var leadIndex = pointedElements.length ? pointedElements[0] : -1;
-
-  // Diff the selection between currentSelection and this.lastSelection_.
-  var selectionFlag = [];
-  for (var i = 0; i < this.lastSelection_.length; i++) {
-    var index = this.lastSelection_[i];
-    // Bit operator can be used for undefined value.
-    selectionFlag[index] =
-        selectionFlag[index] | DragSelector.SelectionFlag_.IN_LAST_SELECTION;
-  }
-  for (var i = 0; i < currentSelection.length; i++) {
-    var index = currentSelection[i];
-    // Bit operator can be used for undefined value.
-    selectionFlag[index] =
-        selectionFlag[index] | DragSelector.SelectionFlag_.IN_CURRENT_SELECTION;
-  }
-
-  // Update the selection
-  this.target_.selectionModel_.beginChange();
-  for (var name in selectionFlag) {
-    var index = parseInt(name);
-    var flag = selectionFlag[name];
-    // The flag may be one of followings:
-    // - IN_LAST_SELECTION | IN_CURRENT_SELECTION
-    // - IN_LAST_SELECTION
-    // - IN_CURRENT_SELECTION
-    // - undefined
-
-    // If the flag equals to (IN_LAST_SELECTION | IN_CURRENT_SELECTION),
-    // this is included in both the last selection and the current selection.
-    // We have nothing to do for this item.
-
-    if (flag == DragSelector.SelectionFlag_.IN_LAST_SELECTION) {
-      // If the flag equals to IN_LAST_SELECTION,
-      // then the item is included in lastSelection but not in currentSelection.
-      // Revert the selection state to this.originalSelection_.
-      this.target_.selectionModel_.setIndexSelected(
-          index, this.originalSelection_.indexOf(index) != -1);
-    } else if (flag == DragSelector.SelectionFlag_.IN_CURRENT_SELECTION) {
-      // If the flag equals to IN_CURRENT_SELECTION,
-      // this is included in currentSelection but not in lastSelection.
-      this.target_.selectionModel_.setIndexSelected(index, true);
-    }
-  }
-  if (leadIndex != -1) {
-    this.target_.selectionModel_.leadIndex = leadIndex;
-    this.target_.selectionModel_.anchorIndex = leadIndex;
-  }
-  this.target_.selectionModel_.endChange();
-  this.lastSelection_ = currentSelection;
-
-  // Update the size of border
-  this.border_.style.left = borderBounds.left + 'px';
-  this.border_.style.top = borderBounds.top + 'px';
-  this.border_.style.width = borderBounds.width + 'px';
-  this.border_.style.height = borderBounds.height + 'px';
-};
-
-/**
- * Handle the mouseup event.
- * @private
- * @param {MouseEvent} event The mouseup event.
- */
-DragSelector.prototype.onMouseUp_ = function(event) {
-  this.onMouseMove_(event);
-  this.target_.removeChild(this.border_);
-  this.target_.ownerDocument.removeEventListener(
-      'mousemove', this.onMouseMoveBound_, true);
-  this.target_.ownerDocument.removeEventListener(
-      'mouseup', this.onMouseUpBound_, true);
-  cr.dispatchSimpleEvent(this.target_, 'dragselectionend');
-  this.target_.cachedBounds = null;
-  this.target_ = null;
-  // The target may select an item by reacting to the mouseup event.
-  // This suppress to the selecting behavior.
-  event.stopPropagation();
-};