/*
 * 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: 40, //No of movements per second
  speed: 1, //No of pixels per frame
  horizontal: true,
  autoMode: 'loop', //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()
    .append('<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);