/*
 * 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: 24, //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.$items[0].offsetHeight; //this.$items[0].offsetHeight;
                        this.clipMax = this.$clip.height(); //this.$clip[0].offsetHeight;
                        this.dimension = 'height';                      
                        this.moveBackClass = 'simply-scroll-btn-up';
                        this.moveForwardClass = 'simply-scroll-btn-down';
                } else {
                        this.itemMax = this.$items[0].offsetWidth;
                        this.clipMax = this.$clip.width();                      
                        this.dimension = 'width';
                        this.moveBackClass = 'simply-scroll-btn-left';
                        this.moveForwardClass = 'simply-scroll-btn-right';
                }
                
                this.posMin = 0;
                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);