remove ntp3 resources

chrome/browser/resources/ntp/drag_drop_controller.js

-// Copyright (c) 2011 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.
-
-// The delegate interface:
-//   dragContainer -->
-//         element containing the draggable items
-//
-//   transitionsDuration -->
-//         length of time of transitions in ms
-//
-//   dragItem -->
-//         get / set property containing the item being dragged
-//
-//   getItem(e) -->
-//         get's the item that is under the mouse event |e|
-//
-//   canDropOn(coordinates) -->
-//         returns true if the coordinates (relative to the drag container)
-//         point to a valid place to drop an item
-//
-//   setDragPlaceholder(coordinates) -->
-//         tells the delegate that the dragged item is currently above
-//         the specified coordinates.
-//
-//   saveDrag(draggedItem) -->
-//         tells the delegate that the drag is done. move the item to the
-//         position last specified by setDragPlaceholder (e.g., commit changes).
-//         draggedItem was the item being dragged.
-//
-
-// The distance, in px, that the mouse must move before initiating a drag.
-var DRAG_THRESHOLD = 35;
-
-function DragAndDropController(delegate) {
-  this.delegate_ = delegate;
-
-  // Install the 'mousedown' handler, the entry point to drag and drop.
-  var el = this.delegate_.dragContainer;
-  el.addEventListener('mousedown', this.handleMouseDown_.bind(this));
-}
-
-DragAndDropController.prototype = {
-  isDragging_: false,
-  startItem_: null,
-  startItemXY_: null,
-  startMouseXY_: null,
-  mouseXY_: null,
-
-  // Enables the handlers that are only active during a drag.
-  enableHandlers_: function() {
-    // Record references to the generated functions so we can
-    // remove the listeners later.
-    this.mouseMoveListener_ = this.handleMouseMove_.bind(this);
-    this.mouseUpListener_ = this.handleMouseUp_.bind(this);
-    this.scrollListener_ = this.handleScroll_.bind(this);
-
-    document.addEventListener('mousemove', this.mouseMoveListener_, true);
-    document.addEventListener('mouseup', this.mouseUpListener_, true);
-    document.addEventListener('scroll', this.scrollListener_, true);
-  },
-
-  disableHandlers_: function() {
-    document.removeEventListener('mousemove', this.mouseMoveListener_, true);
-    document.removeEventListener('mouseup', this.mouseUpListener_, true);
-    document.removeEventListener('scroll', this.scrollListener_, true);
-  },
-
-  isDragging: function() {
-    return this.isDragging_;
-  },
-
-  distance_: function(p1, p2) {
-    var x2 = Math.pow(p1.x - p2.x, 2);
-    var y2 = Math.pow(p1.y - p2.y, 2);
-    return Math.sqrt(x2 + y2);
-  },
-
-  // Shifts the client coordinates, |xy|, so they are relative to the top left
-  // of the drag container.
-  getCoordinates_: function(xy) {
-    var rect = this.delegate_.dragContainer.getBoundingClientRect();
-    var coordinates = {
-      x: xy.x - rect.left,
-      y: xy.y - rect.top
-    };
-
-    // If we're in an RTL language, reflect the coordinates so the delegate
-    // doesn't need to worry about it.
-    if (isRtl())
-      coordinates.x = this.delegate_.dragContainer.offsetWidth - coordinates.x;
-
-    return coordinates;
-  },
-
-  // Listen to mousedown to get the relative position of the cursor when
-  // starting drag and drop.
-  handleMouseDown_: function(e) {
-    var item = this.delegate_.getItem(e);
-
-    // This can't be a drag & drop event if it's not the left mouse button
-    // or if the mouse is not above an item. We also bail out if the dragging
-    // flag is still set (the flag remains around for a bit so that 'click'
-    // event handlers can distinguish between a click and drag).
-    if (!item || e.button != 0 || this.isDragging())
-      return;
-
-    this.startItem_ = item;
-    this.startItemXY_ = {x: item.offsetLeft, y: item.offsetTop};
-    this.startMouseXY_ = {x: e.clientX, y: e.clientY};
-    this.startScrollXY_ = {x: window.scrollX, y: window.scrollY};
-
-    this.enableHandlers_();
-  },
-
-  handleMouseMove_: function(e) {
-    this.mouseXY_ = {x: e.clientX, y: e.clientY};
-
-    if (this.isDragging()) {
-      this.handleDrag_();
-      return;
-    }
-
-    // Initiate the drag if the mouse has moved far enough.
-    if (this.distance_(this.startMouseXY_, this.mouseXY_) >= DRAG_THRESHOLD)
-      this.handleDragStart_();
-  },
-
-  handleMouseUp_: function() {
-    this.handleDrop_();
-  },
-
-  handleScroll_: function(e) {
-    if (this.isDragging())
-      this.handleDrag_();
-  },
-
-  handleDragStart_: function() {
-    // Use the item that the mouse was above when 'mousedown' fired.
-    var item = this.startItem_;
-    if (!item)
-      return;
-
-    this.isDragging_ = true;
-    this.delegate_.dragItem = item;
-    item.classList.add('dragging');
-    item.style.zIndex = 2;
-  },
-
-  handleDragOver_: function() {
-    var coordinates = this.getCoordinates_(this.mouseXY_);
-    if (!this.delegate_.canDropOn(coordinates))
-      return;
-
-    this.delegate_.setDragPlaceholder(coordinates);
-  },
-
-  handleDrop_: function() {
-    this.disableHandlers_();
-
-    var dragItem = this.delegate_.dragItem;
-    if (!dragItem)
-      return;
-
-    this.delegate_.dragItem = this.startItem_ = null;
-    this.delegate_.saveDrag(dragItem);
-    dragItem.classList.remove('dragging');
-
-    setTimeout(function() {
-      // Keep the flag around a little so other 'mouseup' and 'click'
-      // listeners know the event is from a drag operation.
-      this.isDragging_ = false;
-      dragItem.style.zIndex = 0;
-    }.bind(this), this.delegate_.transitionsDuration);
-  },
-
-  handleDrag_: function() {
-    // Moves the drag item making sure that it is not displayed outside the
-    // drag container.
-    var dragItem = this.delegate_.dragItem;
-    var dragContainer = this.delegate_.dragContainer;
-    var rect = dragContainer.getBoundingClientRect();
-
-    // First, move the item the same distance the mouse has moved.
-    var x = this.startItemXY_.x + this.mouseXY_.x - this.startMouseXY_.x +
-              window.scrollX - this.startScrollXY_.x;
-    var y = this.startItemXY_.y + this.mouseXY_.y - this.startMouseXY_.y +
-              window.scrollY - this.startScrollXY_.y;
-
-    var w = this.delegate_.dimensions.width;
-    var h = this.delegate_.dimensions.height;
-
-    var offset = parseInt(getComputedStyle(dragContainer).marginLeft);
-
-    // The position of the item is relative to the drag container. We
-    // want to make sure that half of the item's width or height is within
-    // the container.
-    x = Math.max(x, - w / 2 - offset);
-    x = Math.min(x, rect.width  + w / 2 - offset);
-
-    y = Math.max(- h / 2, y);
-    y = Math.min(y, rect.height - h / 2);
-
-    dragItem.style.left = x + 'px';
-    dragItem.style.top = y + 'px';
-
-    // Update the layouts and positions based on the new drag location.
-    this.handleDragOver_();
-
-    this.delegate_.scrollPage(this.mouseXY_);
-  }
-};