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   1  // script.aculo.us dragdrop.js v1.8.0, Tue Nov 06 15:01:40 +0300 2007
   2  
   3  // Copyright (c) 2005-2007 Thomas Fuchs (http://script.aculo.us, http://mir.aculo.us)
   4  //           (c) 2005-2007 Sammi Williams (http://www.oriontransfer.co.nz, sammi@oriontransfer.co.nz)
   5  // 
   6  // script.aculo.us is freely distributable under the terms of an MIT-style license.
   7  // For details, see the script.aculo.us web site: http://script.aculo.us/
   8  
   9  if(Object.isUndefined(Effect))
  10    throw("dragdrop.js requires including script.aculo.us' effects.js library");
  11  
  12  var Droppables = {
  13    drops: [],
  14  
  15    remove: function(element) {
  16      this.drops = this.drops.reject(function(d) { return d.element==$(element) });
  17    },
  18  
  19    add: function(element) {
  20      element = $(element);
  21      var options = Object.extend({
  22        greedy:     true,
  23        hoverclass: null,
  24        tree:       false
  25      }, arguments[1] || { });
  26  
  27      // cache containers
  28      if(options.containment) {
  29        options._containers = [];
  30        var containment = options.containment;
  31        if(Object.isArray(containment)) {
  32          containment.each( function(c) { options._containers.push($(c)) });
  33        } else {
  34          options._containers.push($(containment));
  35        }
  36      }
  37      
  38      if(options.accept) options.accept = [options.accept].flatten();
  39  
  40      Element.makePositioned(element); // fix IE
  41      options.element = element;
  42  
  43      this.drops.push(options);
  44    },
  45    
  46    findDeepestChild: function(drops) {
  47      deepest = drops[0];
  48        
  49      for (i = 1; i < drops.length; ++i)
  50        if (Element.isParent(drops[i].element, deepest.element))
  51          deepest = drops[i];
  52      
  53      return deepest;
  54    },
  55  
  56    isContained: function(element, drop) {
  57      var containmentNode;
  58      if(drop.tree) {
  59        containmentNode = element.treeNode; 
  60      } else {
  61        containmentNode = element.parentNode;
  62      }
  63      return drop._containers.detect(function(c) { return containmentNode == c });
  64    },
  65    
  66    isAffected: function(point, element, drop) {
  67      return (
  68        (drop.element!=element) &&
  69        ((!drop._containers) ||
  70          this.isContained(element, drop)) &&
  71        ((!drop.accept) ||
  72          (Element.classNames(element).detect( 
  73            function(v) { return drop.accept.include(v) } ) )) &&
  74        Position.within(drop.element, point[0], point[1]) );
  75    },
  76  
  77    deactivate: function(drop) {
  78      if(drop.hoverclass)
  79        Element.removeClassName(drop.element, drop.hoverclass);
  80      this.last_active = null;
  81    },
  82  
  83    activate: function(drop) {
  84      if(drop.hoverclass)
  85        Element.addClassName(drop.element, drop.hoverclass);
  86      this.last_active = drop;
  87    },
  88  
  89    show: function(point, element) {
  90      if(!this.drops.length) return;
  91      var drop, affected = [];
  92      
  93      this.drops.each( function(drop) {
  94        if(Droppables.isAffected(point, element, drop))
  95          affected.push(drop);
  96      });
  97          
  98      if(affected.length>0)
  99        drop = Droppables.findDeepestChild(affected);
 100  
 101      if(this.last_active && this.last_active != drop) this.deactivate(this.last_active);
 102      if (drop) {
 103        Position.within(drop.element, point[0], point[1]);
 104        if(drop.onHover)
 105          drop.onHover(element, drop.element, Position.overlap(drop.overlap, drop.element));
 106        
 107        if (drop != this.last_active) Droppables.activate(drop);
 108      }
 109    },
 110  
 111    fire: function(event, element) {
 112      if(!this.last_active) return;
 113      Position.prepare();
 114  
 115      if (this.isAffected([Event.pointerX(event), Event.pointerY(event)], element, this.last_active))
 116        if (this.last_active.onDrop) {
 117          this.last_active.onDrop(element, this.last_active.element, event); 
 118          return true; 
 119        }
 120    },
 121  
 122    reset: function() {
 123      if(this.last_active)
 124        this.deactivate(this.last_active);
 125    }
 126  }
 127  
 128  var Draggables = {
 129    drags: [],
 130    observers: [],
 131    
 132    register: function(draggable) {
 133      if(this.drags.length == 0) {
 134        this.eventMouseUp   = this.endDrag.bindAsEventListener(this);
 135        this.eventMouseMove = this.updateDrag.bindAsEventListener(this);
 136        this.eventKeypress  = this.keyPress.bindAsEventListener(this);
 137        
 138        Event.observe(document, "mouseup", this.eventMouseUp);
 139        Event.observe(document, "mousemove", this.eventMouseMove);
 140        Event.observe(document, "keypress", this.eventKeypress);
 141      }
 142      this.drags.push(draggable);
 143    },
 144    
 145    unregister: function(draggable) {
 146      this.drags = this.drags.reject(function(d) { return d==draggable });
 147      if(this.drags.length == 0) {
 148        Event.stopObserving(document, "mouseup", this.eventMouseUp);
 149        Event.stopObserving(document, "mousemove", this.eventMouseMove);
 150        Event.stopObserving(document, "keypress", this.eventKeypress);
 151      }
 152    },
 153    
 154    activate: function(draggable) {
 155      if(draggable.options.delay) { 
 156        this._timeout = setTimeout(function() { 
 157          Draggables._timeout = null; 
 158          window.focus(); 
 159          Draggables.activeDraggable = draggable; 
 160        }.bind(this), draggable.options.delay); 
 161      } else {
 162        window.focus(); // allows keypress events if window isn't currently focused, fails for Safari
 163        this.activeDraggable = draggable;
 164      }
 165    },
 166    
 167    deactivate: function() {
 168      this.activeDraggable = null;
 169    },
 170    
 171    updateDrag: function(event) {
 172      if(!this.activeDraggable) return;
 173      var pointer = [Event.pointerX(event), Event.pointerY(event)];
 174      // Mozilla-based browsers fire successive mousemove events with
 175      // the same coordinates, prevent needless redrawing (moz bug?)
 176      if(this._lastPointer && (this._lastPointer.inspect() == pointer.inspect())) return;
 177      this._lastPointer = pointer;
 178      
 179      this.activeDraggable.updateDrag(event, pointer);
 180    },
 181    
 182    endDrag: function(event) {
 183      if(this._timeout) { 
 184        clearTimeout(this._timeout); 
 185        this._timeout = null; 
 186      }
 187      if(!this.activeDraggable) return;
 188      this._lastPointer = null;
 189      this.activeDraggable.endDrag(event);
 190      this.activeDraggable = null;
 191    },
 192    
 193    keyPress: function(event) {
 194      if(this.activeDraggable)
 195        this.activeDraggable.keyPress(event);
 196    },
 197    
 198    addObserver: function(observer) {
 199      this.observers.push(observer);
 200      this._cacheObserverCallbacks();
 201    },
 202    
 203    removeObserver: function(element) {  // element instead of observer fixes mem leaks
 204      this.observers = this.observers.reject( function(o) { return o.element==element });
 205      this._cacheObserverCallbacks();
 206    },
 207    
 208    notify: function(eventName, draggable, event) {  // 'onStart', 'onEnd', 'onDrag'
 209      if(this[eventName+'Count'] > 0)
 210        this.observers.each( function(o) {
 211          if(o[eventName]) o[eventName](eventName, draggable, event);
 212        });
 213      if(draggable.options[eventName]) draggable.options[eventName](draggable, event);
 214    },
 215    
 216    _cacheObserverCallbacks: function() {
 217      ['onStart','onEnd','onDrag'].each( function(eventName) {
 218        Draggables[eventName+'Count'] = Draggables.observers.select(
 219          function(o) { return o[eventName]; }
 220        ).length;
 221      });
 222    }
 223  }
 224  
 225  /*--------------------------------------------------------------------------*/
 226  
 227  var Draggable = Class.create({
 228    initialize: function(element) {
 229      var defaults = {
 230        handle: false,
 231        reverteffect: function(element, top_offset, left_offset) {
 232          var dur = Math.sqrt(Math.abs(top_offset^2)+Math.abs(left_offset^2))*0.02;
 233          new Effect.Move(element, { x: -left_offset, y: -top_offset, duration: dur,
 234            queue: {scope:'_draggable', position:'end'}
 235          });
 236        },
 237        endeffect: function(element) {
 238          var toOpacity = Object.isNumber(element._opacity) ? element._opacity : 1.0;
 239          new Effect.Opacity(element, {duration:0.2, from:0.7, to:toOpacity, 
 240            queue: {scope:'_draggable', position:'end'},
 241            afterFinish: function(){ 
 242              Draggable._dragging[element] = false 
 243            }
 244          }); 
 245        },
 246        zindex: 1000,
 247        revert: false,
 248        quiet: false,
 249        scroll: false,
 250        scrollSensitivity: 20,
 251        scrollSpeed: 15,
 252        snap: false,  // false, or xy or [x,y] or function(x,y){ return [x,y] }
 253        delay: 0
 254      };
 255      
 256      if(!arguments[1] || Object.isUndefined(arguments[1].endeffect))
 257        Object.extend(defaults, {
 258          starteffect: function(element) {
 259            element._opacity = Element.getOpacity(element);
 260            Draggable._dragging[element] = true;
 261            new Effect.Opacity(element, {duration:0.2, from:element._opacity, to:0.7}); 
 262          }
 263        });
 264      
 265      var options = Object.extend(defaults, arguments[1] || { });
 266  
 267      this.element = $(element);
 268      
 269      if(options.handle && Object.isString(options.handle))
 270        this.handle = this.element.down('.'+options.handle, 0);
 271      
 272      if(!this.handle) this.handle = $(options.handle);
 273      if(!this.handle) this.handle = this.element;
 274      
 275      if(options.scroll && !options.scroll.scrollTo && !options.scroll.outerHTML) {
 276        options.scroll = $(options.scroll);
 277        this._isScrollChild = Element.childOf(this.element, options.scroll);
 278      }
 279  
 280      Element.makePositioned(this.element); // fix IE    
 281  
 282      this.options  = options;
 283      this.dragging = false;   
 284  
 285      this.eventMouseDown = this.initDrag.bindAsEventListener(this);
 286      Event.observe(this.handle, "mousedown", this.eventMouseDown);
 287      
 288      Draggables.register(this);
 289    },
 290    
 291    destroy: function() {
 292      Event.stopObserving(this.handle, "mousedown", this.eventMouseDown);
 293      Draggables.unregister(this);
 294    },
 295    
 296    currentDelta: function() {
 297      return([
 298        parseInt(Element.getStyle(this.element,'left') || '0'),
 299        parseInt(Element.getStyle(this.element,'top') || '0')]);
 300    },
 301    
 302    initDrag: function(event) {
 303      if(!Object.isUndefined(Draggable._dragging[this.element]) &&
 304        Draggable._dragging[this.element]) return;
 305      if(Event.isLeftClick(event)) {    
 306        // abort on form elements, fixes a Firefox issue
 307        var src = Event.element(event);
 308        if((tag_name = src.tagName.toUpperCase()) && (
 309          tag_name=='INPUT' ||
 310          tag_name=='SELECT' ||
 311          tag_name=='OPTION' ||
 312          tag_name=='BUTTON' ||
 313          tag_name=='TEXTAREA')) return;
 314          
 315        var pointer = [Event.pointerX(event), Event.pointerY(event)];
 316        var pos     = Position.cumulativeOffset(this.element);
 317        this.offset = [0,1].map( function(i) { return (pointer[i] - pos[i]) });
 318        
 319        Draggables.activate(this);
 320        Event.stop(event);
 321      }
 322    },
 323    
 324    startDrag: function(event) {
 325      this.dragging = true;
 326      if(!this.delta)
 327        this.delta = this.currentDelta();
 328      
 329      if(this.options.zindex) {
 330        this.originalZ = parseInt(Element.getStyle(this.element,'z-index') || 0);
 331        this.element.style.zIndex = this.options.zindex;
 332      }
 333      
 334      if(this.options.ghosting) {
 335        this._clone = this.element.cloneNode(true);
 336        this.element._originallyAbsolute = (this.element.getStyle('position') == 'absolute');
 337        if (!this.element._originallyAbsolute)
 338          Position.absolutize(this.element);
 339        this.element.parentNode.insertBefore(this._clone, this.element);
 340      }
 341      
 342      if(this.options.scroll) {
 343        if (this.options.scroll == window) {
 344          var where = this._getWindowScroll(this.options.scroll);
 345          this.originalScrollLeft = where.left;
 346          this.originalScrollTop = where.top;
 347        } else {
 348          this.originalScrollLeft = this.options.scroll.scrollLeft;
 349          this.originalScrollTop = this.options.scroll.scrollTop;
 350        }
 351      }
 352      
 353      Draggables.notify('onStart', this, event);
 354          
 355      if(this.options.starteffect) this.options.starteffect(this.element);
 356    },
 357    
 358    updateDrag: function(event, pointer) {
 359      if(!this.dragging) this.startDrag(event);
 360      
 361      if(!this.options.quiet){
 362        Position.prepare();
 363        Droppables.show(pointer, this.element);
 364      }
 365      
 366      Draggables.notify('onDrag', this, event);
 367      
 368      this.draw(pointer);
 369      if(this.options.change) this.options.change(this);
 370      
 371      if(this.options.scroll) {
 372        this.stopScrolling();
 373        
 374        var p;
 375        if (this.options.scroll == window) {
 376          with(this._getWindowScroll(this.options.scroll)) { p = [ left, top, left+width, top+height ]; }
 377        } else {
 378          p = Position.page(this.options.scroll);
 379          p[0] += this.options.scroll.scrollLeft + Position.deltaX;
 380          p[1] += this.options.scroll.scrollTop + Position.deltaY;
 381          p.push(p[0]+this.options.scroll.offsetWidth);
 382          p.push(p[1]+this.options.scroll.offsetHeight);
 383        }
 384        var speed = [0,0];
 385        if(pointer[0] < (p[0]+this.options.scrollSensitivity)) speed[0] = pointer[0]-(p[0]+this.options.scrollSensitivity);
 386        if(pointer[1] < (p[1]+this.options.scrollSensitivity)) speed[1] = pointer[1]-(p[1]+this.options.scrollSensitivity);
 387        if(pointer[0] > (p[2]-this.options.scrollSensitivity)) speed[0] = pointer[0]-(p[2]-this.options.scrollSensitivity);
 388        if(pointer[1] > (p[3]-this.options.scrollSensitivity)) speed[1] = pointer[1]-(p[3]-this.options.scrollSensitivity);
 389        this.startScrolling(speed);
 390      }
 391      
 392      // fix AppleWebKit rendering
 393      if(Prototype.Browser.WebKit) window.scrollBy(0,0);
 394      
 395      Event.stop(event);
 396    },
 397    
 398    finishDrag: function(event, success) {
 399      this.dragging = false;
 400      
 401      if(this.options.quiet){
 402        Position.prepare();
 403        var pointer = [Event.pointerX(event), Event.pointerY(event)];
 404        Droppables.show(pointer, this.element);
 405      }
 406  
 407      if(this.options.ghosting) {
 408        if (!this.element._originallyAbsolute)
 409          Position.relativize(this.element);
 410        delete this.element._originallyAbsolute;
 411        Element.remove(this._clone);
 412        this._clone = null;
 413      }
 414  
 415      var dropped = false; 
 416      if(success) { 
 417        dropped = Droppables.fire(event, this.element); 
 418        if (!dropped) dropped = false; 
 419      }
 420      if(dropped && this.options.onDropped) this.options.onDropped(this.element);
 421      Draggables.notify('onEnd', this, event);
 422  
 423      var revert = this.options.revert;
 424      if(revert && Object.isFunction(revert)) revert = revert(this.element);
 425      
 426      var d = this.currentDelta();
 427      if(revert && this.options.reverteffect) {
 428        if (dropped == 0 || revert != 'failure')
 429          this.options.reverteffect(this.element,
 430            d[1]-this.delta[1], d[0]-this.delta[0]);
 431      } else {
 432        this.delta = d;
 433      }
 434  
 435      if(this.options.zindex)
 436        this.element.style.zIndex = this.originalZ;
 437  
 438      if(this.options.endeffect) 
 439        this.options.endeffect(this.element);
 440        
 441      Draggables.deactivate(this);
 442      Droppables.reset();
 443    },
 444    
 445    keyPress: function(event) {
 446      if(event.keyCode!=Event.KEY_ESC) return;
 447      this.finishDrag(event, false);
 448      Event.stop(event);
 449    },
 450    
 451    endDrag: function(event) {
 452      if(!this.dragging) return;
 453      this.stopScrolling();
 454      this.finishDrag(event, true);
 455      Event.stop(event);
 456    },
 457    
 458    draw: function(point) {
 459      var pos = Position.cumulativeOffset(this.element);
 460      if(this.options.ghosting) {
 461        var r   = Position.realOffset(this.element);
 462        pos[0] += r[0] - Position.deltaX; pos[1] += r[1] - Position.deltaY;
 463      }
 464      
 465      var d = this.currentDelta();
 466      pos[0] -= d[0]; pos[1] -= d[1];
 467      
 468      if(this.options.scroll && (this.options.scroll != window && this._isScrollChild)) {
 469        pos[0] -= this.options.scroll.scrollLeft-this.originalScrollLeft;
 470        pos[1] -= this.options.scroll.scrollTop-this.originalScrollTop;
 471      }
 472      
 473      var p = [0,1].map(function(i){ 
 474        return (point[i]-pos[i]-this.offset[i]) 
 475      }.bind(this));
 476      
 477      if(this.options.snap) {
 478        if(Object.isFunction(this.options.snap)) {
 479          p = this.options.snap(p[0],p[1],this);
 480        } else {
 481        if(Object.isArray(this.options.snap)) {
 482          p = p.map( function(v, i) {
 483            return (v/this.options.snap[i]).round()*this.options.snap[i] }.bind(this))
 484        } else {
 485          p = p.map( function(v) {
 486            return (v/this.options.snap).round()*this.options.snap }.bind(this))
 487        }
 488      }}
 489      
 490      var style = this.element.style;
 491      if((!this.options.constraint) || (this.options.constraint=='horizontal'))
 492        style.left = p[0] + "px";
 493      if((!this.options.constraint) || (this.options.constraint=='vertical'))
 494        style.top  = p[1] + "px";
 495      
 496      if(style.visibility=="hidden") style.visibility = ""; // fix gecko rendering
 497    },
 498    
 499    stopScrolling: function() {
 500      if(this.scrollInterval) {
 501        clearInterval(this.scrollInterval);
 502        this.scrollInterval = null;
 503        Draggables._lastScrollPointer = null;
 504      }
 505    },
 506    
 507    startScrolling: function(speed) {
 508      if(!(speed[0] || speed[1])) return;
 509      this.scrollSpeed = [speed[0]*this.options.scrollSpeed,speed[1]*this.options.scrollSpeed];
 510      this.lastScrolled = new Date();
 511      this.scrollInterval = setInterval(this.scroll.bind(this), 10);
 512    },
 513    
 514    scroll: function() {
 515      var current = new Date();
 516      var delta = current - this.lastScrolled;
 517      this.lastScrolled = current;
 518      if(this.options.scroll == window) {
 519        with (this._getWindowScroll(this.options.scroll)) {
 520          if (this.scrollSpeed[0] || this.scrollSpeed[1]) {
 521            var d = delta / 1000;
 522            this.options.scroll.scrollTo( left + d*this.scrollSpeed[0], top + d*this.scrollSpeed[1] );
 523          }
 524        }
 525      } else {
 526        this.options.scroll.scrollLeft += this.scrollSpeed[0] * delta / 1000;
 527        this.options.scroll.scrollTop  += this.scrollSpeed[1] * delta / 1000;
 528      }
 529      
 530      Position.prepare();
 531      Droppables.show(Draggables._lastPointer, this.element);
 532      Draggables.notify('onDrag', this);
 533      if (this._isScrollChild) {
 534        Draggables._lastScrollPointer = Draggables._lastScrollPointer || $A(Draggables._lastPointer);
 535        Draggables._lastScrollPointer[0] += this.scrollSpeed[0] * delta / 1000;
 536        Draggables._lastScrollPointer[1] += this.scrollSpeed[1] * delta / 1000;
 537        if (Draggables._lastScrollPointer[0] < 0)
 538          Draggables._lastScrollPointer[0] = 0;
 539        if (Draggables._lastScrollPointer[1] < 0)
 540          Draggables._lastScrollPointer[1] = 0;
 541        this.draw(Draggables._lastScrollPointer);
 542      }
 543      
 544      if(this.options.change) this.options.change(this);
 545    },
 546    
 547    _getWindowScroll: function(w) {
 548      var T, L, W, H;
 549      with (w.document) {
 550        if (w.document.documentElement && documentElement.scrollTop) {
 551          T = documentElement.scrollTop;
 552          L = documentElement.scrollLeft;
 553        } else if (w.document.body) {
 554          T = body.scrollTop;
 555          L = body.scrollLeft;
 556        }
 557        if (w.innerWidth) {
 558          W = w.innerWidth;
 559          H = w.innerHeight;
 560        } else if (w.document.documentElement && documentElement.clientWidth) {
 561          W = documentElement.clientWidth;
 562          H = documentElement.clientHeight;
 563        } else {
 564          W = body.offsetWidth;
 565          H = body.offsetHeight
 566        }
 567      }
 568      return { top: T, left: L, width: W, height: H };
 569    }
 570  });
 571  
 572  Draggable._dragging = { };
 573  
 574  /*--------------------------------------------------------------------------*/
 575  
 576  var SortableObserver = Class.create({
 577    initialize: function(element, observer) {
 578      this.element   = $(element);
 579      this.observer  = observer;
 580      this.lastValue = Sortable.serialize(this.element);
 581    },
 582    
 583    onStart: function() {
 584      this.lastValue = Sortable.serialize(this.element);
 585    },
 586    
 587    onEnd: function() {
 588      Sortable.unmark();
 589      if(this.lastValue != Sortable.serialize(this.element))
 590        this.observer(this.element)
 591    }
 592  });
 593  
 594  var Sortable = {
 595    SERIALIZE_RULE: /^[^_\-](?:[A-Za-z0-9\-\_]*)[_](.*)$/,
 596    
 597    sortables: { },
 598    
 599    _findRootElement: function(element) {
 600      while (element.tagName.toUpperCase() != "BODY") {  
 601        if(element.id && Sortable.sortables[element.id]) return element;
 602        element = element.parentNode;
 603      }
 604    },
 605  
 606    options: function(element) {
 607      element = Sortable._findRootElement($(element));
 608      if(!element) return;
 609      return Sortable.sortables[element.id];
 610    },
 611    
 612    destroy: function(element){
 613      var s = Sortable.options(element);
 614      
 615      if(s) {
 616        Draggables.removeObserver(s.element);
 617        s.droppables.each(function(d){ Droppables.remove(d) });
 618        s.draggables.invoke('destroy');
 619        
 620        delete Sortable.sortables[s.element.id];
 621      }
 622    },
 623  
 624    create: function(element) {
 625      element = $(element);
 626      var options = Object.extend({ 
 627        element:     element,
 628        tag:         'li',       // assumes li children, override with tag: 'tagname'
 629        dropOnEmpty: false,
 630        tree:        false,
 631        treeTag:     'ul',
 632        overlap:     'vertical', // one of 'vertical', 'horizontal'
 633        constraint:  'vertical', // one of 'vertical', 'horizontal', false
 634        containment: element,    // also takes array of elements (or id's); or false
 635        handle:      false,      // or a CSS class
 636        only:        false,
 637        delay:       0,
 638        hoverclass:  null,
 639        ghosting:    false,
 640        quiet:       false, 
 641        scroll:      false,
 642        scrollSensitivity: 20,
 643        scrollSpeed: 15,
 644        format:      this.SERIALIZE_RULE,
 645        
 646        // these take arrays of elements or ids and can be 
 647        // used for better initialization performance
 648        elements:    false,
 649        handles:     false,
 650        
 651        onChange:    Prototype.emptyFunction,
 652        onUpdate:    Prototype.emptyFunction
 653      }, arguments[1] || { });
 654  
 655      // clear any old sortable with same element
 656      this.destroy(element);
 657  
 658      // build options for the draggables
 659      var options_for_draggable = {
 660        revert:      true,
 661        quiet:       options.quiet,
 662        scroll:      options.scroll,
 663        scrollSpeed: options.scrollSpeed,
 664        scrollSensitivity: options.scrollSensitivity,
 665        delay:       options.delay,
 666        ghosting:    options.ghosting,
 667        constraint:  options.constraint,
 668        handle:      options.handle };
 669  
 670      if(options.starteffect)
 671        options_for_draggable.starteffect = options.starteffect;
 672  
 673      if(options.reverteffect)
 674        options_for_draggable.reverteffect = options.reverteffect;
 675      else
 676        if(options.ghosting) options_for_draggable.reverteffect = function(element) {
 677          element.style.top  = 0;
 678          element.style.left = 0;
 679        };
 680  
 681      if(options.endeffect)
 682        options_for_draggable.endeffect = options.endeffect;
 683  
 684      if(options.zindex)
 685        options_for_draggable.zindex = options.zindex;
 686  
 687      // build options for the droppables  
 688      var options_for_droppable = {
 689        overlap:     options.overlap,
 690        containment: options.containment,
 691        tree:        options.tree,
 692        hoverclass:  options.hoverclass,
 693        onHover:     Sortable.onHover
 694      }
 695      
 696      var options_for_tree = {
 697        onHover:      Sortable.onEmptyHover,
 698        overlap:      options.overlap,
 699        containment:  options.containment,
 700        hoverclass:   options.hoverclass
 701      }
 702  
 703      // fix for gecko engine
 704      Element.cleanWhitespace(element); 
 705  
 706      options.draggables = [];
 707      options.droppables = [];
 708  
 709      // drop on empty handling
 710      if(options.dropOnEmpty || options.tree) {
 711        Droppables.add(element, options_for_tree);
 712        options.droppables.push(element);
 713      }
 714  
 715      (options.elements || this.findElements(element, options) || []).each( function(e,i) {
 716        var handle = options.handles ? $(options.handles[i]) :
 717          (options.handle ? $(e).select('.' + options.handle)[0] : e); 
 718        options.draggables.push(
 719          new Draggable(e, Object.extend(options_for_draggable, { handle: handle })));
 720        Droppables.add(e, options_for_droppable);
 721        if(options.tree) e.treeNode = element;
 722        options.droppables.push(e);      
 723      });
 724      
 725      if(options.tree) {
 726        (Sortable.findTreeElements(element, options) || []).each( function(e) {
 727          Droppables.add(e, options_for_tree);
 728          e.treeNode = element;
 729          options.droppables.push(e);
 730        });
 731      }
 732  
 733      // keep reference
 734      this.sortables[element.id] = options;
 735  
 736      // for onupdate
 737      Draggables.addObserver(new SortableObserver(element, options.onUpdate));
 738  
 739    },
 740  
 741    // return all suitable-for-sortable elements in a guaranteed order
 742    findElements: function(element, options) {
 743      return Element.findChildren(
 744        element, options.only, options.tree ? true : false, options.tag);
 745    },
 746    
 747    findTreeElements: function(element, options) {
 748      return Element.findChildren(
 749        element, options.only, options.tree ? true : false, options.treeTag);
 750    },
 751  
 752    onHover: function(element, dropon, overlap) {
 753      if(Element.isParent(dropon, element)) return;
 754  
 755      if(overlap > .33 && overlap < .66 && Sortable.options(dropon).tree) {
 756        return;
 757      } else if(overlap>0.5) {
 758        Sortable.mark(dropon, 'before');
 759        if(dropon.previousSibling != element) {
 760          var oldParentNode = element.parentNode;
 761          element.style.visibility = "hidden"; // fix gecko rendering
 762          dropon.parentNode.insertBefore(element, dropon);
 763          if(dropon.parentNode!=oldParentNode) 
 764            Sortable.options(oldParentNode).onChange(element);
 765          Sortable.options(dropon.parentNode).onChange(element);
 766        }
 767      } else {
 768        Sortable.mark(dropon, 'after');
 769        var nextElement = dropon.nextSibling || null;
 770        if(nextElement != element) {
 771          var oldParentNode = element.parentNode;
 772          element.style.visibility = "hidden"; // fix gecko rendering
 773          dropon.parentNode.insertBefore(element, nextElement);
 774          if(dropon.parentNode!=oldParentNode) 
 775            Sortable.options(oldParentNode).onChange(element);
 776          Sortable.options(dropon.parentNode).onChange(element);
 777        }
 778      }
 779    },
 780    
 781    onEmptyHover: function(element, dropon, overlap) {
 782      var oldParentNode = element.parentNode;
 783      var droponOptions = Sortable.options(dropon);
 784          
 785      if(!Element.isParent(dropon, element)) {
 786        var index;
 787        
 788        var children = Sortable.findElements(dropon, {tag: droponOptions.tag, only: droponOptions.only});
 789        var child = null;
 790              
 791        if(children) {
 792          var offset = Element.offsetSize(dropon, droponOptions.overlap) * (1.0 - overlap);
 793          
 794          for (index = 0; index < children.length; index += 1) {
 795            if (offset - Element.offsetSize (children[index], droponOptions.overlap) >= 0) {
 796              offset -= Element.offsetSize (children[index], droponOptions.overlap);
 797            } else if (offset - (Element.offsetSize (children[index], droponOptions.overlap) / 2) >= 0) {
 798              child = index + 1 < children.length ? children[index + 1] : null;
 799              break;
 800            } else {
 801              child = children[index];
 802              break;
 803            }
 804          }
 805        }
 806        
 807        dropon.insertBefore(element, child);
 808        
 809        Sortable.options(oldParentNode).onChange(element);
 810        droponOptions.onChange(element);
 811      }
 812    },
 813  
 814    unmark: function() {
 815      if(Sortable._marker) Sortable._marker.hide();
 816    },
 817  
 818    mark: function(dropon, position) {
 819      // mark on ghosting only
 820      var sortable = Sortable.options(dropon.parentNode);
 821      if(sortable && !sortable.ghosting) return; 
 822  
 823      if(!Sortable._marker) {
 824        Sortable._marker = 
 825          ($('dropmarker') || Element.extend(document.createElement('DIV'))).
 826            hide().addClassName('dropmarker').setStyle({position:'absolute'});
 827        document.getElementsByTagName("body").item(0).appendChild(Sortable._marker);
 828      }    
 829      var offsets = Position.cumulativeOffset(dropon);
 830      Sortable._marker.setStyle({left: offsets[0]+'px', top: offsets[1] + 'px'});
 831      
 832      if(position=='after')
 833        if(sortable.overlap == 'horizontal') 
 834          Sortable._marker.setStyle({left: (offsets[0]+dropon.clientWidth) + 'px'});
 835        else
 836          Sortable._marker.setStyle({top: (offsets[1]+dropon.clientHeight) + 'px'});
 837      
 838      Sortable._marker.show();
 839    },
 840    
 841    _tree: function(element, options, parent) {
 842      var children = Sortable.findElements(element, options) || [];
 843    
 844      for (var i = 0; i < children.length; ++i) {
 845        var match = children[i].id.match(options.format);
 846  
 847        if (!match) continue;
 848        
 849        var child = {
 850          id: encodeURIComponent(match ? match[1] : null),
 851          element: element,
 852          parent: parent,
 853          children: [],
 854          position: parent.children.length,
 855          container: $(children[i]).down(options.treeTag)
 856        }
 857        
 858        /* Get the element containing the children and recurse over it */
 859        if (child.container)
 860          this._tree(child.container, options, child)
 861        
 862        parent.children.push (child);
 863      }
 864  
 865      return parent; 
 866    },
 867  
 868    tree: function(element) {
 869      element = $(element);
 870      var sortableOptions = this.options(element);
 871      var options = Object.extend({
 872        tag: sortableOptions.tag,
 873        treeTag: sortableOptions.treeTag,
 874        only: sortableOptions.only,
 875        name: element.id,
 876        format: sortableOptions.format
 877      }, arguments[1] || { });
 878      
 879      var root = {
 880        id: null,
 881        parent: null,
 882        children: [],
 883        container: element,
 884        position: 0
 885      }
 886      
 887      return Sortable._tree(element, options, root);
 888    },
 889  
 890    /* Construct a [i] index for a particular node */
 891    _constructIndex: function(node) {
 892      var index = '';
 893      do {
 894        if (node.id) index = '[' + node.position + ']' + index;
 895      } while ((node = node.parent) != null);
 896      return index;
 897    },
 898  
 899    sequence: function(element) {
 900      element = $(element);
 901      var options = Object.extend(this.options(element), arguments[1] || { });
 902      
 903      return $(this.findElements(element, options) || []).map( function(item) {
 904        return item.id.match(options.format) ? item.id.match(options.format)[1] : '';
 905      });
 906    },
 907  
 908    setSequence: function(element, new_sequence) {
 909      element = $(element);
 910      var options = Object.extend(this.options(element), arguments[2] || { });
 911      
 912      var nodeMap = { };
 913      this.findElements(element, options).each( function(n) {
 914          if (n.id.match(options.format))
 915              nodeMap[n.id.match(options.format)[1]] = [n, n.parentNode];
 916          n.parentNode.removeChild(n);
 917      });
 918     
 919      new_sequence.each(function(ident) {
 920        var n = nodeMap[ident];
 921        if (n) {
 922          n[1].appendChild(n[0]);
 923          delete nodeMap[ident];
 924        }
 925      });
 926    },
 927    
 928    serialize: function(element) {
 929      element = $(element);
 930      var options = Object.extend(Sortable.options(element), arguments[1] || { });
 931      var name = encodeURIComponent(
 932        (arguments[1] && arguments[1].name) ? arguments[1].name : element.id);
 933      
 934      if (options.tree) {
 935        return Sortable.tree(element, arguments[1]).children.map( function (item) {
 936          return [name + Sortable._constructIndex(item) + "[id]=" + 
 937                  encodeURIComponent(item.id)].concat(item.children.map(arguments.callee));
 938        }).flatten().join('&');
 939      } else {
 940        return Sortable.sequence(element, arguments[1]).map( function(item) {
 941          return name + "[]=" + encodeURIComponent(item);
 942        }).join('&');
 943      }
 944    }
 945  }
 946  
 947  // Returns true if child is contained within element
 948  Element.isParent = function(child, element) {
 949    if (!child.parentNode || child == element) return false;
 950    if (child.parentNode == element) return true;
 951    return Element.isParent(child.parentNode, element);
 952  }
 953  
 954  Element.findChildren = function(element, only, recursive, tagName) {   
 955    if(!element.hasChildNodes()) return null;
 956    tagName = tagName.toUpperCase();
 957    if(only) only = [only].flatten();
 958    var elements = [];
 959    $A(element.childNodes).each( function(e) {
 960      if(e.tagName && e.tagName.toUpperCase()==tagName &&
 961        (!only || (Element.classNames(e).detect(function(v) { return only.include(v) }))))
 962          elements.push(e);
 963      if(recursive) {
 964        var grandchildren = Element.findChildren(e, only, recursive, tagName);
 965        if(grandchildren) elements.push(grandchildren);
 966      }
 967    });
 968  
 969    return (elements.length>0 ? elements.flatten() : []);
 970  }
 971  
 972  Element.offsetSize = function (element, type) {
 973    return element['offset' + ((type=='vertical' || type=='height') ? 'Height' : 'Width')];
 974  }