/*
 * simplyScroll 1.0.4 - a scroll-tastic jQuery plugin
 *
 * http://logicbox.net/jquery/simplyscroll
 * http://logicbox.net/blog/simplyscroll-jquery-plugin
 * http://plugins.jquery.com/project/simplyScroll
 *
 * Copyright (c) 2009 Will Kelly - http://logicbox.net
 *
 * Dual licensed under the MIT (MIT-LICENSE.txt)
 * and GPL (GPL-LICENSE.txt) licenses.
 *
 * Last revised: 03/07/2009 21:13
 *
 */

(function($) {

$.fn.simplyScroll = function(o) {
	return this.each(function() {
		new $.simplyScroll(this,o);
	});
};

var defaults = {
	className: 'simply-scroll',
	frameRate: 28, //No of movements per second
	speed: 1, //No of pixels per frame
	horizontal: true,
	autoMode: 'off', //disables buttons 'loop','bounce'
	pauseOnHover: true,
	startOnLoad: false, //use this if having rendering problems (safari 3 + Mac OSX?)
	localJsonSource: '', //format [{"src":"images/pic.jpg","title":"title","link":"http://"},{etc..}]
	flickrFeed: '',
	jsonImgWidth: 240,
	jsonImgHeight: 180
};
	
$.simplyScroll = function(el,o) {
	
	var self = this;
	
	this.o = $.extend({}, defaults, o || {});
	this.auto = this.o.autoMode!=="off" ? true : false;
	
	//called on ul/ol/div etc
	this.$list = $(el);
	
	//generate extra markup
	this.$list.addClass('simply-scroll-list')
		.wrap('<div class="simply-scroll-clip"></div>')
		.parent().wrap('<div class="' + this.o.className + ' simply-scroll-container"></div>');
	
	if (!this.o.auto) { //button placeholders
		this.$list.parent().parent()
		.prepend('<div class="simply-scroll-forward"></div>')
		.prepend('<div class="simply-scroll-back"></div>');
	}
	
	//load image data
	if (this.o.flickrFeed) {
		$.getJSON(this.o.flickrFeed + "&format=json&jsoncallback=?",
			function(data) {
				json = [];
				$.each(data.items, function(i,item) {
					json.push({
						"src": item.media.m,
						"title": item.title,
						"link": item.link
					});
				});
				self.renderData(json);
			}
		);
	} else if (this.o.localJsonSource) {
		$.getJSON(this.o.localJsonSource,
			function(json) {
				self.renderData(json);
			}
		);
	} else {
		
		if (!this.o.startOnLoad) {
			this.init();
		} else {
			//wait for load before completing setup
			$(window).load(function() { self.init();  });
		}
		
	}
		
};
	
$.simplyScroll.fn = $.simplyScroll.prototype = {};

$.simplyScroll.fn.extend = $.simplyScroll.extend = $.extend;

$.simplyScroll.fn.extend({
	init: function() {
		//shortcuts
		this.$items = this.$list.children();
		this.$clip = this.$list.parent();
		this.$container = this.$clip.parent();

		if (!this.o.horizontal) {
			this.itemMax = this.$items.eq(0).outerHeight(true); 
			this.clipMax = this.$clip.height();
			this.dimension = 'height';			
			this.moveBackClass = 'simply-scroll-btn-up';
			this.moveForwardClass = 'simply-scroll-btn-down';
		} else {
			this.itemMax = this.$items.eq(0).outerWidth(true);
			this.clipMax = this.$clip.width();			
			this.dimension = 'width';
			this.moveBackClass = 'simply-scroll-btn-left';
			this.moveForwardClass = 'simply-scroll-btn-right';
		}
		
		this.posMin = 0;
		
		/* 
		IMPORTANT: The script assumes multiple elements within a list are the same width or height 
		to work out how many extra elements to generate to simulate the loop. 
		
		If you want this script to work with unequal sized elements don't modify the next line 
		to do this:
		
		this.$items.each(function() {
			self.posMax += !this.o.horizontal ? $(this).outerHeight(true) : $(this).outerWidth(true);
		});
		
		as it will cause white-space and a jump to appear when elements have wildly different dimensions
		See: http://logicbox.net/jquery/simplyscroll/test_unequalelements.html
		
		Instead simply add an extra wrapper element around your list and init simplyScroll on that, 
		essentially scrolling just one element. Less efficient but it does the job!
		
		*/
		this.posMax = this.$items.length * this.itemMax;
		
		this.$list.css(this.dimension,this.posMax +'px');
		
		if (this.o.autoMode=='loop') {
			var addItems = Math.ceil(this.clipMax / this.itemMax);	
			this.$items.slice(0,addItems).clone(true).appendTo(this.$list);
			this.posMax += (this.clipMax - this.o.speed);
			this.$list.css(this.dimension,this.posMax+(this.itemMax*addItems) +'px');
		}
		
		this.interval = null;	
		this.intervalDelay = Math.floor(1000 / this.o.frameRate);
		
		//ensure that speed is divisible by item width
		while (this.itemMax % this.o.speed !== 0) {
			this.o.speed--;
			if (this.o.speed===0) {
				this.o.speed=1; break;	
			}
		}
		
		var self = this;
		this.trigger = null;
		this.funcMoveBack = function() { self.trigger=this;self.moveBack(); };
		this.funcMoveForward = function() { self.trigger=this;self.moveForward(); };
		this.funcMoveStop = function() { self.moveStop(); };
		this.funcMoveResume = function() { self.moveResume(); };
		
		if (this.auto) {
			if (this.o.pauseOnHover) {
				this.$clip.hover(this.funcMoveStop,this.funcMoveResume);
			}
			this.moveForward();
		} else {
			this.$btnBack = $('.simply-scroll-back',this.$container)
				.addClass('simply-scroll-btn' + ' ' + this.moveBackClass + ' ' + 'disabled')
				.hover(this.funcMoveBack,this.funcMoveStop);
			this.$btnForward = $('.simply-scroll-forward',this.$container)
				.addClass('simply-scroll-btn' + ' ' + this.moveForwardClass)
				.hover(this.funcMoveForward,this.funcMoveStop);
		}
	},
	moveForward: function() {
		var self = this;
		this.movement = 'forward';
		if (this.trigger !== null) {
			this.$btnBack.removeClass('disabled');
		}
		self.interval = setInterval(function() {
			if (!self.o.horizontal && self.$clip[0].scrollTop < (self.posMax-self.clipMax)) {
				self.$clip[0].scrollTop += self.o.speed;
			} else if (self.o.horizontal && self.$clip[0].scrollLeft < (self.posMax-self.clipMax)) {
				self.$clip[0].scrollLeft += self.o.speed; 
			} else if (self.o.autoMode=='loop') {
				self.resetPos();
			} else {
				self.moveStop(self.movement);
			}
		},self.intervalDelay);
	},
	moveBack: function() {
		var self = this;
		this.movement = 'back';
		if (this.trigger !== null) {
			this.$btnForward.removeClass('disabled');
		}
		self.interval = setInterval(function() {
			if (!self.o.horizontal && self.$clip[0].scrollTop>0) {
				self.$clip[0].scrollTop -= self.o.speed;
			} else if (self.o.horizontal && self.$clip[0].scrollLeft>0) {
				self.$clip[0].scrollLeft -= self.o.speed;
			} else if (self.o.autoMode=='loop') {
				self.resetPos();
			} else {
				self.moveStop(self.movement);
			}
		},self.intervalDelay);
	},
	moveStop: function(moveDir) {
		clearInterval(this.interval);	
		if (this.trigger!==null) {
			if (typeof moveDir != "undefined") {
				$(this.trigger).addClass('disabled');
			}
			this.trigger = null;
		}
		if (this.auto) {
			if (this.o.autoMode=='bounce') {
				moveDir == 'forward' ? this.moveBack() : this.moveForward();
			}
		}
	},
	moveResume: function() {
		this.movement=='forward' ? this.moveForward() : this.moveBack();
	},
	resetPos: function() {
		if (!this.o.horizontal) {
			this.$clip[0].scrollTop = 0;
		} else {
			this.$clip[0].scrollLeft = 0;
		}
	},
	renderData: function(json) {
		if (json.length>0) { //render json data
			var self = this;
			$.each(json, function(i,item) {
				$("<img/>").attr({
					src: item.src,
					title: item.title,
					alt: item.title,
					width: self.o.jsonImgWidth,
					height: self.o.jsonImgHeight
				}).appendTo(self.$list);
			});
			this.init();
		}
	}
});
		  
})(jQuery);