/*
+ * This is a derivative of the similarly named class in the YUI Library.
+ * The original license:
+ * Copyright (c) 2006, Yahoo! Inc. All rights reserved.
+ * Code licensed under the BSD License:
+ * http://developer.yahoo.net/yui/license.txt
+ */
+
+
+/**
+ * @class Ext.dd.DD
+ * A DragDrop implementation where the linked element follows the
+ * mouse cursor during a drag.
+ * @extends Ext.dd.DragDrop
+ * @constructor
+ * @param {String} id the id of the linked element
+ * @param {String} sGroup the group of related DragDrop items
+ * @param {object} config an object containing configurable attributes
+ * Valid properties for DD:
+ * scroll
+ */
+
+Ext.define('Ext.dd.DD', {
+ extend: 'Ext.dd.DragDrop',
+ requires: ['Ext.dd.DragDropManager'],
+ constructor: function(id, sGroup, config) {
+ if (id) {
+ this.init(id, sGroup, config);
+ }
+ },
+
+ /**
+ * When set to true, the utility automatically tries to scroll the browser
+ * window when a drag and drop element is dragged near the viewport boundary.
+ * Defaults to true.
+ * @property scroll
+ * @type boolean
+ */
+ scroll: true,
+
+ /**
+ * Sets the pointer offset to the distance between the linked element's top
+ * left corner and the location the element was clicked
+ * @method autoOffset
+ * @param {int} iPageX the X coordinate of the click
+ * @param {int} iPageY the Y coordinate of the click
+ */
+ autoOffset: function(iPageX, iPageY) {
+ var x = iPageX - this.startPageX;
+ var y = iPageY - this.startPageY;
+ this.setDelta(x, y);
+ },
+
+ /**
+ * Sets the pointer offset. You can call this directly to force the
+ * offset to be in a particular location (e.g., pass in 0,0 to set it
+ * to the center of the object)
+ * @method setDelta
+ * @param {int} iDeltaX the distance from the left
+ * @param {int} iDeltaY the distance from the top
+ */
+ setDelta: function(iDeltaX, iDeltaY) {
+ this.deltaX = iDeltaX;
+ this.deltaY = iDeltaY;
+ },
+
+ /**
+ * Sets the drag element to the location of the mousedown or click event,
+ * maintaining the cursor location relative to the location on the element
+ * that was clicked. Override this if you want to place the element in a
+ * location other than where the cursor is.
+ * @method setDragElPos
+ * @param {int} iPageX the X coordinate of the mousedown or drag event
+ * @param {int} iPageY the Y coordinate of the mousedown or drag event
+ */
+ setDragElPos: function(iPageX, iPageY) {
+ // the first time we do this, we are going to check to make sure
+ // the element has css positioning
+
+ var el = this.getDragEl();
+ this.alignElWithMouse(el, iPageX, iPageY);
+ },
+
+ /**
+ * Sets the element to the location of the mousedown or click event,
+ * maintaining the cursor location relative to the location on the element
+ * that was clicked. Override this if you want to place the element in a
+ * location other than where the cursor is.
+ * @method alignElWithMouse
+ * @param {HTMLElement} el the element to move
+ * @param {int} iPageX the X coordinate of the mousedown or drag event
+ * @param {int} iPageY the Y coordinate of the mousedown or drag event
+ */
+ alignElWithMouse: function(el, iPageX, iPageY) {
+ var oCoord = this.getTargetCoord(iPageX, iPageY),
+ fly = el.dom ? el : Ext.fly(el, '_dd'),
+ elSize = fly.getSize(),
+ EL = Ext.core.Element,
+ vpSize;
+
+ if (!this.deltaSetXY) {
+ vpSize = this.cachedViewportSize = { width: EL.getDocumentWidth(), height: EL.getDocumentHeight() };
+ var aCoord = [
+ Math.max(0, Math.min(oCoord.x, vpSize.width - elSize.width)),
+ Math.max(0, Math.min(oCoord.y, vpSize.height - elSize.height))
+ ];
+ fly.setXY(aCoord);
+ var newLeft = fly.getLeft(true);
+ var newTop = fly.getTop(true);
+ this.deltaSetXY = [newLeft - oCoord.x, newTop - oCoord.y];
+ } else {
+ vpSize = this.cachedViewportSize;
+ fly.setLeftTop(
+ Math.max(0, Math.min(oCoord.x + this.deltaSetXY[0], vpSize.width - elSize.width)),
+ Math.max(0, Math.min(oCoord.y + this.deltaSetXY[1], vpSize.height - elSize.height))
+ );
+ }
+
+ this.cachePosition(oCoord.x, oCoord.y);
+ this.autoScroll(oCoord.x, oCoord.y, el.offsetHeight, el.offsetWidth);
+ return oCoord;
+ },
+
+ /**
+ * Saves the most recent position so that we can reset the constraints and
+ * tick marks on-demand. We need to know this so that we can calculate the
+ * number of pixels the element is offset from its original position.
+ * @method cachePosition
+ * @param iPageX the current x position (optional, this just makes it so we
+ * don't have to look it up again)
+ * @param iPageY the current y position (optional, this just makes it so we
+ * don't have to look it up again)
+ */
+ cachePosition: function(iPageX, iPageY) {
+ if (iPageX) {
+ this.lastPageX = iPageX;
+ this.lastPageY = iPageY;
+ } else {
+ var aCoord = Ext.core.Element.getXY(this.getEl());
+ this.lastPageX = aCoord[0];
+ this.lastPageY = aCoord[1];
+ }
+ },
+
+ /**
+ * Auto-scroll the window if the dragged object has been moved beyond the
+ * visible window boundary.
+ * @method autoScroll
+ * @param {int} x the drag element's x position
+ * @param {int} y the drag element's y position
+ * @param {int} h the height of the drag element
+ * @param {int} w the width of the drag element
+ * @private
+ */
+ autoScroll: function(x, y, h, w) {
+
+ if (this.scroll) {
+ // The client height
+ var clientH = Ext.core.Element.getViewHeight();
+
+ // The client width
+ var clientW = Ext.core.Element.getViewWidth();
+
+ // The amt scrolled down
+ var st = this.DDMInstance.getScrollTop();
+
+ // The amt scrolled right
+ var sl = this.DDMInstance.getScrollLeft();
+
+ // Location of the bottom of the element
+ var bot = h + y;
+
+ // Location of the right of the element
+ var right = w + x;
+
+ // The distance from the cursor to the bottom of the visible area,
+ // adjusted so that we don't scroll if the cursor is beyond the
+ // element drag constraints
+ var toBot = (clientH + st - y - this.deltaY);
+
+ // The distance from the cursor to the right of the visible area
+ var toRight = (clientW + sl - x - this.deltaX);
+
+
+ // How close to the edge the cursor must be before we scroll
+ // var thresh = (document.all) ? 100 : 40;
+ var thresh = 40;
+
+ // How many pixels to scroll per autoscroll op. This helps to reduce
+ // clunky scrolling. IE is more sensitive about this ... it needs this
+ // value to be higher.
+ var scrAmt = (document.all) ? 80 : 30;
+
+ // Scroll down if we are near the bottom of the visible page and the
+ // obj extends below the crease
+ if ( bot > clientH && toBot < thresh ) {
+ window.scrollTo(sl, st + scrAmt);
+ }
+
+ // Scroll up if the window is scrolled down and the top of the object
+ // goes above the top border
+ if ( y < st && st > 0 && y - st < thresh ) {
+ window.scrollTo(sl, st - scrAmt);
+ }
+
+ // Scroll right if the obj is beyond the right border and the cursor is
+ // near the border.
+ if ( right > clientW && toRight < thresh ) {
+ window.scrollTo(sl + scrAmt, st);
+ }
+
+ // Scroll left if the window has been scrolled to the right and the obj
+ // extends past the left border
+ if ( x < sl && sl > 0 && x - sl < thresh ) {
+ window.scrollTo(sl - scrAmt, st);
+ }
+ }
+ },
+
+ /**
+ * Finds the location the element should be placed if we want to move
+ * it to where the mouse location less the click offset would place us.
+ * @method getTargetCoord
+ * @param {int} iPageX the X coordinate of the click
+ * @param {int} iPageY the Y coordinate of the click
+ * @return an object that contains the coordinates (Object.x and Object.y)
+ * @private
+ */
+ getTargetCoord: function(iPageX, iPageY) {
+ var x = iPageX - this.deltaX;
+ var y = iPageY - this.deltaY;
+
+ if (this.constrainX) {
+ if (x < this.minX) {
+ x = this.minX;
+ }
+ if (x > this.maxX) {
+ x = this.maxX;
+ }
+ }
+
+ if (this.constrainY) {
+ if (y < this.minY) {
+ y = this.minY;
+ }
+ if (y > this.maxY) {
+ y = this.maxY;
+ }
+ }
+
+ x = this.getTick(x, this.xTicks);
+ y = this.getTick(y, this.yTicks);
+
+
+ return {x: x, y: y};
+ },
+
+ /**
+ * Sets up config options specific to this class. Overrides
+ * Ext.dd.DragDrop, but all versions of this method through the
+ * inheritance chain are called
+ */
+ applyConfig: function() {
+ this.callParent();
+ this.scroll = (this.config.scroll !== false);
+ },
+
+ /**
+ * Event that fires prior to the onMouseDown event. Overrides
+ * Ext.dd.DragDrop.
+ */
+ b4MouseDown: function(e) {
+ // this.resetConstraints();
+ this.autoOffset(e.getPageX(), e.getPageY());
+ },
+
+ /**
+ * Event that fires prior to the onDrag event. Overrides
+ * Ext.dd.DragDrop.
+ */
+ b4Drag: function(e) {
+ this.setDragElPos(e.getPageX(), e.getPageY());
+ },
+
+ toString: function() {
+ return ("DD " + this.id);
+ }
+
+ //////////////////////////////////////////////////////////////////////////
+ // Debugging ygDragDrop events that can be overridden
+ //////////////////////////////////////////////////////////////////////////
+ /*
+ startDrag: function(x, y) {
+ },
+
+ onDrag: function(e) {
+ },
+
+ onDragEnter: function(e, id) {
+ },
+
+ onDragOver: function(e, id) {
+ },
+
+ onDragOut: function(e, id) {
+ },
+
+ onDragDrop: function(e, id) {
+ },
+
+ endDrag: function(e) {
+ }
+
+ */
+
+});
+