// script.aculo.us slider.js v1.7.1_beta3, Fri May 25 17:19:41 +0200 2007

// Copyright (c) 2005-2007 Marty Haught, Thomas Fuchs
//
// script.aculo.us is freely distributable under the terms of an MIT-style license.
// For details, see the script.aculo.us web site: http://script.aculo.us/

if(!Control) var Control = {};
Control.Slider = Class.create();

// options:
// axis: 'vertical', or 'horizontal' (default)
//
// callbacks:
// onChange(value)
// onSlide(value)
Control.Slider.prototype = {
 initialize: function(handle, track, options) {
 var slider = this;

 if(handle instanceof Array) {
 this.handles = handle.collect( function(e) { return $(e) });
 } else {
 this.handles = [$(handle)];
 }

 this.track = $(track);
 this.options = options || {};

 this.axis = this.options.axis || 'horizontal';
 this.increment = this.options.increment || 1;
 this.step = parseInt(this.options.step || '1');
 this.range = this.options.range || $R(0,1);

 this.value = 0; // assure backwards compat
 this.values = this.handles.map( function() { return 0 });
 this.spans = this.options.spans ? this.options.spans.map(function(s){ return $(s) }) : false;
 this.options.startSpan = $(this.options.startSpan || null);
 this.options.endSpan = $(this.options.endSpan || null);

 this.restricted = this.options.restricted || false;

 this.maximum = this.options.maximum || this.range.end;
 this.minimum = this.options.minimum || this.range.start;

 // Will be used to align the handle onto the track, if necessary
 this.alignX = parseInt(this.options.alignX || '0');
 this.alignY = parseInt(this.options.alignY || '0');

 this.trackLength = this.maximumOffset() - this.minimumOffset();

 this.handleLength = this.isVertical() ?
 (this.handles[0].offsetHeight != 0 ?
 this.handles[0].offsetHeight : this.handles[0].style.height.replace(/px$/,"")) :
 (this.handles[0].offsetWidth != 0 ? this.handles[0].offsetWidth :
 this.handles[0].style.width.replace(/px$/,""));

 this.active = false;
 this.dragging = false;
 this.disabled = false;

 if(this.options.disabled) this.setDisabled();

 // Allowed values array
 this.allowedValues = this.options.values ? this.options.values.sortBy(Prototype.K) : false;
 if(this.allowedValues) {
 this.minimum = this.allowedValues.min();
 this.maximum = this.allowedValues.max();
 }

 this.eventMouseDown = this.startDrag.bindAsEventListener(this);
 this.eventMouseUp = this.endDrag.bindAsEventListener(this);
 this.eventMouseMove = this.update.bindAsEventListener(this);

 // Initialize handles in reverse (make sure first handle is active)
 this.handles.each( function(h,i) {
 i = slider.handles.length-1-i;
 slider.setValue(parseFloat(
 (slider.options.sliderValue instanceof Array ?
 slider.options.sliderValue[i] : slider.options.sliderValue) ||
 slider.range.start), i);
 Element.makePositioned(h); // fix IE
 Event.observe(h, "mousedown", slider.eventMouseDown);
 });

 Event.observe(this.track, "mousedown", this.eventMouseDown);
 Event.observe(document, "mouseup", this.eventMouseUp);
 Event.observe(this.track.parentNode.parentNode, "mousemove", this.eventMouseMove);

 this.initialized = true;
 },
 dispose: function() {
 var slider = this;
 Event.stopObserving(this.track, "mousedown", this.eventMouseDown);
 Event.stopObserving(document, "mouseup", this.eventMouseUp);
 Event.stopObserving(this.track.parentNode.parentNode, "mousemove", this.eventMouseMove);
 this.handles.each( function(h) {
 Event.stopObserving(h, "mousedown", slider.eventMouseDown);
 });
 },
 setDisabled: function(){
 this.disabled = true;
 },
 setEnabled: function(){
 this.disabled = false;
 },
 getNearestValue: function(value){
 if(this.allowedValues){
 if(value >= this.allowedValues.max()) return(this.allowedValues.max());
 if(value <= this.allowedValues.min()) return(this.allowedValues.min());

 var offset = Math.abs(this.allowedValues[0] - value);
 var newValue = this.allowedValues[0];
 this.allowedValues.each( function(v) {
 var currentOffset = Math.abs(v - value);
 if(currentOffset <= offset){
 newValue = v;
 offset = currentOffset;
 }
 });
 return newValue;
 }
 if(value > this.range.end) return this.range.end;
 if(value < this.range.start) return this.range.start;
 return value;
 },
 setValue: function(sliderValue, handleIdx){
 if(!this.active) {
 this.activeHandleIdx = handleIdx || 0;
 this.activeHandle = this.handles[this.activeHandleIdx];
 this.updateStyles();
 }
 handleIdx = handleIdx || this.activeHandleIdx || 0;
 if(this.initialized && this.restricted) {
 if((handleIdx>0) && (sliderValue<this.values[handleIdx-1]))
 sliderValue = this.values[handleIdx-1];
 if((handleIdx < (this.handles.length-1)) && (sliderValue>this.values[handleIdx+1]))
 sliderValue = this.values[handleIdx+1];
 }
 sliderValue = this.getNearestValue(sliderValue);
 this.values[handleIdx] = sliderValue;
 this.value = this.values[0]; // assure backwards compat

 this.handles[handleIdx].style[this.isVertical() ? 'top' : 'left'] =
 this.translateToPx(sliderValue);

 this.drawSpans();
 if(!this.dragging || !this.event) this.updateFinished();
 },
 setValueBy: function(delta, handleIdx) {
 this.setValue(this.values[handleIdx || this.activeHandleIdx || 0] + delta,
 handleIdx || this.activeHandleIdx || 0);
 },
 translateToPx: function(value) {
 return Math.round(
 ((this.trackLength-this.handleLength)/(this.range.end-this.range.start)) *
 (value - this.range.start)) + "px";
 },
 translateToValue: function(offset) {
 return ((offset/(this.trackLength-this.handleLength) *
 (this.range.end-this.range.start)) + this.range.start);
 },
 getRange: function(range) {
 var v = this.values.sortBy(Prototype.K);
 range = range || 0;
 return $R(v[range],v[range+1]);
 },
 minimumOffset: function(){
 return(this.isVertical() ? this.alignY : this.alignX);
 },
 maximumOffset: function(){
 return(this.isVertical() ?
 (this.track.offsetHeight != 0 ? this.track.offsetHeight :
 this.track.style.height.replace(/px$/,"")) - this.alignY :
 (this.track.offsetWidth != 0 ? this.track.offsetWidth :
 this.track.style.width.replace(/px$/,"")) - this.alignY);
 },
 isVertical: function(){
 return (this.axis == 'vertical');
 },
 drawSpans: function() {
 var slider = this;
 if(this.spans)
 $R(0, this.spans.length-1).each(function(r) { slider.setSpan(slider.spans[r], slider.getRange(r)) });
 if(this.options.startSpan)
 this.setSpan(this.options.startSpan,
 $R(0, this.values.length>1 ? this.getRange(0).min() : this.value ));
 if(this.options.endSpan)
 this.setSpan(this.options.endSpan,
 $R(this.values.length>1 ? this.getRange(this.spans.length-1).max() : this.value, this.maximum));
 },
 setSpan: function(span, range) {
 if(this.isVertical()) {
 span.style.top = this.translateToPx(range.start);
 span.style.height = this.translateToPx(range.end - range.start + this.range.start);
 } else {
 span.style.left = this.translateToPx(range.start);
 span.style.width = this.translateToPx(range.end - range.start + this.range.start);
 }
 },
 updateStyles: function() {
 this.handles.each( function(h){ Element.removeClassName(h, 'selected') });
 Element.addClassName(this.activeHandle, 'selected');
 },
 startDrag: function(event) {
 if(Event.isLeftClick(event)) {
 if(!this.disabled){
 this.active = true;

 var handle = Event.element(event);
 var pointer = [Event.pointerX(event), Event.pointerY(event)];
 var track = handle;
 if(track==this.track) {
 var offsets = Position.cumulativeOffset(this.track);
 this.event = event;
 this.setValue(this.translateToValue(
 (this.isVertical() ? pointer[1]-offsets[1] : pointer[0]-offsets[0])-(this.handleLength/2)
 ));
 var offsets = Position.cumulativeOffset(this.activeHandle);
 this.offsetX = (pointer[0] - offsets[0]);
 this.offsetY = (pointer[1] - offsets[1]);
 } else {
 // find the handle (prevents issues with Safari)
 while((this.handles.indexOf(handle) == -1) && handle.parentNode)
 handle = handle.parentNode;

 if(this.handles.indexOf(handle)!=-1) {
 this.activeHandle = handle;
 this.activeHandleIdx = this.handles.indexOf(this.activeHandle);
 this.updateStyles();

 var offsets = Position.cumulativeOffset(this.activeHandle);
 this.offsetX = (pointer[0] - offsets[0]);
 this.offsetY = (pointer[1] - offsets[1]);
 }
 }
 }
 Event.stop(event);
 }
 },
 update: function(event) {
 if(this.active) {
 if(!this.dragging) this.dragging = true;
 this.draw(event);
 if(Prototype.Browser.WebKit) window.scrollBy(0,0);
 Event.stop(event);
 }
 },
 draw: function(event) {
 var pointer = [Event.pointerX(event), Event.pointerY(event)];
 var offsets = Position.cumulativeOffset(this.track);
 pointer[0] -= this.offsetX + offsets[0];
 pointer[1] -= this.offsetY + offsets[1];
 this.event = event;
 this.setValue(this.translateToValue( this.isVertical() ? pointer[1] : pointer[0] ));
 if(this.initialized && this.options.onSlide)
 this.options.onSlide(this.values.length>1 ? this.values : this.value, this);
 },
 endDrag: function(event) {
 if(this.active && this.dragging) {
 this.finishDrag(event, true);
 Event.stop(event);
 }
 this.active = false;
 this.dragging = false;
 },
 finishDrag: function(event, success) {
 this.active = false;
 this.dragging = false;
 this.updateFinished();
 },
 updateFinished: function() {
 if(this.initialized && this.options.onChange)
 this.options.onChange(this.values.length>1 ? this.values : this.value, this);
 this.event = null;
 }
}
