/*
* jQuery UI Droppable
*
* Copyright (c) 2008 Paul Bakaus
* Dual licensed under the MIT (MIT-LICENSE.txt)
* and GPL (GPL-LICENSE.txt) licenses.
* 
* http://docs.jquery.com/UI/Droppables
*
* Depends:
*	ui.core.js
*	ui.draggable.js
*/
(function($) {

    $.widget("ui.droppable", {
        init: function() {

            this.element.addClass("ui-droppable");
            this.isover = 0; this.isout = 1;

            //Prepare the passed options
            var o = this.options, accept = o.accept;
            o = $.extend(o, {
                accept: o.accept && o.accept.constructor == Function ? o.accept : function(d) {
                    return $(d).is(accept);
                }
            });

            //Store the droppable's proportions
            this.proportions = { width: this.element[0].offsetWidth, height: this.element[0].offsetHeight };

            // Add the reference and positions to the manager
            $.ui.ddmanager.droppables.push(this);

        },
        plugins: {},
        ui: function(c) {
            return {
                draggable: (c.currentItem || c.element),
                helper: c.helper,
                position: c.position,
                absolutePosition: c.positionAbs,
                options: this.options,
                element: this.element
            };
        },
        destroy: function() {
            var drop = $.ui.ddmanager.droppables;
            for (var i = 0; i < drop.length; i++)
                if (drop[i] == this)
                drop.splice(i, 1);

            this.element
			.removeClass("ui-droppable ui-droppable-disabled")
			.removeData("droppable")
			.unbind(".droppable");
        },
        over: function(e) {

            var draggable = $.ui.ddmanager.current;
            if (!draggable || (draggable.currentItem || draggable.element)[0] == this.element[0]) return; // Bail if draggable and droppable are same element

            if (this.options.accept.call(this.element, (draggable.currentItem || draggable.element))) {
                $.ui.plugin.call(this, 'over', [e, this.ui(draggable)]);
                this.element.triggerHandler("dropover", [e, this.ui(draggable)], this.options.over);
            }

        },
        out: function(e) {

            var draggable = $.ui.ddmanager.current;
            if (!draggable || (draggable.currentItem || draggable.element)[0] == this.element[0]) return; // Bail if draggable and droppable are same element

            if (this.options.accept.call(this.element, (draggable.currentItem || draggable.element))) {
                $.ui.plugin.call(this, 'out', [e, this.ui(draggable)]);
                this.element.triggerHandler("dropout", [e, this.ui(draggable)], this.options.out);
            }

        },
        drop: function(e, custom) {

            var draggable = custom || $.ui.ddmanager.current;
            if (!draggable || (draggable.currentItem || draggable.element)[0] == this.element[0]) return false; // Bail if draggable and droppable are same element

            var childrenIntersection = false;
            this.element.find(".ui-droppable").not(".ui-draggable-dragging").each(function() {
                var inst = $.data(this, 'droppable');
                if (inst.options.greedy && $.ui.intersect(draggable, $.extend(inst, { offset: inst.element.offset() }), inst.options.tolerance)) {
                    childrenIntersection = true; return false;
                }
            });
            if (childrenIntersection) return false;

            if (this.options.accept.call(this.element, (draggable.currentItem || draggable.element))) {
                $.ui.plugin.call(this, 'drop', [e, this.ui(draggable)]);
                this.element.triggerHandler("drop", [e, this.ui(draggable)], this.options.drop);
                return true;
            }

            return false;

        },
        activate: function(e) {

            var draggable = $.ui.ddmanager.current;
            $.ui.plugin.call(this, 'activate', [e, this.ui(draggable)]);
            if (draggable) this.element.triggerHandler("dropactivate", [e, this.ui(draggable)], this.options.activate);

        },
        deactivate: function(e) {

            var draggable = $.ui.ddmanager.current;
            $.ui.plugin.call(this, 'deactivate', [e, this.ui(draggable)]);
            if (draggable) this.element.triggerHandler("dropdeactivate", [e, this.ui(draggable)], this.options.deactivate);

        }
    });

    $.extend($.ui.droppable, {
        defaults: {
            disabled: false,
            tolerance: 'intersect'
        }
    });

    $.ui.intersect = function(draggable, droppable, toleranceMode) {

        if (!droppable.offset) return false;

        var x1 = (draggable.positionAbs || draggable.position.absolute).left, x2 = x1 + draggable.helperProportions.width,
		y1 = (draggable.positionAbs || draggable.position.absolute).top, y2 = y1 + draggable.helperProportions.height;
        var l = droppable.offset.left, r = l + droppable.proportions.width,
		t = droppable.offset.top, b = t + droppable.proportions.height;

        switch (toleranceMode) {
            case 'fit':
                return (l < x1 && x2 < r
				&& t < y1 && y2 < b);
                break;
            case 'intersect':
                return (l < x1 + (draggable.helperProportions.width / 2) // Right Half
				&& x2 - (draggable.helperProportions.width / 2) < r // Left Half
				&& t < y1 + (draggable.helperProportions.height / 2) // Bottom Half
				&& y2 - (draggable.helperProportions.height / 2) < b); // Top Half
                break;
            case 'pointer':
                return (l < ((draggable.positionAbs || draggable.position.absolute).left + (draggable.clickOffset || draggable.offset.click).left) && ((draggable.positionAbs || draggable.position.absolute).left + (draggable.clickOffset || draggable.offset.click).left) < r
				&& t < ((draggable.positionAbs || draggable.position.absolute).top + (draggable.clickOffset || draggable.offset.click).top) && ((draggable.positionAbs || draggable.position.absolute).top + (draggable.clickOffset || draggable.offset.click).top) < b);
                break;
            case 'touch':
                return (
					(y1 >= t && y1 <= b) || // Top edge touching
					(y2 >= t && y2 <= b) || // Bottom edge touching
					(y1 < t && y2 > b)		// Surrounded vertically
				) && (
					(x1 >= l && x1 <= r) || // Left edge touching
					(x2 >= l && x2 <= r) || // Right edge touching
					(x1 < l && x2 > r)		// Surrounded horizontally
				);
                break;
            default:
                return false;
                break;
        }

    };

    /*
    This manager tracks offsets of draggables and droppables
    */
    $.ui.ddmanager = {
        current: null,
        droppables: [],
        prepareOffsets: function(t, e) {

            var m = $.ui.ddmanager.droppables;
            var type = e ? e.type : null; // workaround for #2317

            for (var i = 0; i < m.length; i++) {
                if (m[i].options.disabled || (t && !m[i].options.accept.call(m[i].element, (t.currentItem || t.element)))) continue;
                m[i].visible = m[i].element.css("display") != "none"; if (!m[i].visible) continue; //If the element is not visible, continue
                m[i].offset = m[i].element.offset();
                m[i].proportions = { width: m[i].element[0].offsetWidth, height: m[i].element[0].offsetHeight };

                if (type == "dragstart" || type == "sortactivate") m[i].activate.call(m[i], e); //Activate the droppable if used directly from draggables
            }

        },
        drop: function(draggable, e) {

            var dropped = false;
            $.each($.ui.ddmanager.droppables, function() {

                if (!this.options) return;
                if (!this.options.disabled && this.visible && $.ui.intersect(draggable, this, this.options.tolerance))
                    dropped = this.drop.call(this, e);

                if (!this.options.disabled && this.visible && this.options.accept.call(this.element, (draggable.currentItem || draggable.element))) {
                    this.isout = 1; this.isover = 0;
                    this.deactivate.call(this, e);
                }

            });
            return dropped;

        },
        drag: function(draggable, e) {

            //If you have a highly dynamic page, you might try this option. It renders positions every time you move the mouse.
            if (draggable.options.refreshPositions) $.ui.ddmanager.prepareOffsets(draggable, e);

            //Run through all droppables and check their positions based on specific tolerance options

            $.each($.ui.ddmanager.droppables, function() {

                if (this.options.disabled || this.greedyChild || !this.visible) return;
                var intersects = $.ui.intersect(draggable, this, this.options.tolerance);

                var c = !intersects && this.isover == 1 ? 'isout' : (intersects && this.isover == 0 ? 'isover' : null);
                if (!c) return;

                var parentInstance;
                if (this.options.greedy) {
                    var parent = this.element.parents('.ui-droppable:eq(0)');
                    if (parent.length) {
                        parentInstance = $.data(parent[0], 'droppable');
                        parentInstance.greedyChild = (c == 'isover' ? 1 : 0);
                    }
                }

                // we just moved into a greedy child
                if (parentInstance && c == 'isover') {
                    parentInstance['isover'] = 0;
                    parentInstance['isout'] = 1;
                    parentInstance.out.call(parentInstance, e);
                }

                this[c] = 1; this[c == 'isout' ? 'isover' : 'isout'] = 0;
                this[c == "isover" ? "over" : "out"].call(this, e);

                // we just moved out of a greedy child
                if (parentInstance && c == 'isout') {
                    parentInstance['isout'] = 0;
                    parentInstance['isover'] = 1;
                    parentInstance.over.call(parentInstance, e);
                }
            });

        }
    };

    /*
    * Droppable Extensions
    */

    $.ui.plugin.add("droppable", "activeClass", {
        activate: function(e, ui) {
            $(this).addClass(ui.options.activeClass);
        },
        deactivate: function(e, ui) {
            $(this).removeClass(ui.options.activeClass);
        },
        drop: function(e, ui) {
            $(this).removeClass(ui.options.activeClass);
        }
    });

    $.ui.plugin.add("droppable", "hoverClass", {
        over: function(e, ui) {
            $(this).addClass(ui.options.hoverClass);
        },
        out: function(e, ui) {
            $(this).removeClass(ui.options.hoverClass);
        },
        drop: function(e, ui) {
            $(this).removeClass(ui.options.hoverClass);
        }
    });

})(jQuery);