/*!
 * jQuery jCarousellite Plugin v1.5
 *
 * Date: Tue Sep 06 13:30:06 2011 EDT
 * Requires: jQuery v1.4+
 *
 * Copyright 2007 Ganeshji Marwaha (gmarwaha.com)
 * Modifications/enhancements by Karl Swedberg
 * Dual licensed under the MIT and GPL licenses (just like jQuery):
 * http://www.opensource.org/licenses/mit-license.php
 * http://www.gnu.org/licenses/gpl.html
 *
 * jQuery plugin to navigate images/any content in a carousel style widget.
 *
*/

(function($) {

$.jCarouselLite = {
  version: '1.5'
};

$.fn.jCarouselLite = function(options) {
  var o = $.extend({}, $.fn.jCarouselLite.defaults, options);

  this.each(function() {

    var sizes = {},
        running = false,
        animCss = o.vertical ? "top": "left",
        aniProps = {},
        sizeProp = o.vertical ? "height": "width",
        self = this,
        div = $(this),
        ul = div.find('ul').eq(0),
        tLi = ul.children('li'),
        tl = tLi.length,
        v = o.visible,
        start = Math.min(o.start, tl-1);

    if (o.circular) {
        ul.prepend(tLi.slice(tl-v-1+1).clone(true))
          .append(tLi.slice(0,v).clone(true));
        start += v;
    }
    var li = ul.children('li'),
        itemLength = li.length,
        curr = start;

    div.css("visibility", "visible");

    if (o.autoCSS) {
      li.css({overflow: o.vertical ? 'hidden' : 'visible', 'float': o.vertical ? 'none' : 'left'});
      ul.css({margin: '0', padding: '0', position: 'relative', listStyleType: 'none', zIndex: 1});
      div.css({visibility: 'visible', overflow: 'hidden', position: 'relative', zIndex: 2, left: '0px'});
    }

    // Full li size(incl margin)-Used for animation
    var liSize = o.vertical ? height(li) : width(li);

    // size of full ul(total length, not just for the visible items)
    var ulSize = liSize * itemLength;

    // size of entire div(total length for just the visible items)
    var divSize = liSize * v;

    if (o.autoCSS) {
      sizes[sizeProp] = divSize + 'px';
      div.css(sizes);
      li.css({width: li.width(), height: li.height()});
    }
    sizes[sizeProp] = ulSize + 'px';
    sizes[animCss] = -(curr*liSize);
    ul.css(sizes);

    // set up timed advancer
    var advanceCounter = 0,
        autoStop = iterations(tl,o);

    var advancer = function() {
      self.setAutoAdvance = setTimeout(function() {

        if (!autoStop || autoStop > advanceCounter) {
          go(curr+o.scroll);
          advanceCounter++;
          advancer();
        }
      }, o.timeout+o.speed);
    };

    // bind click handlers to prev and next buttons, if set
    $.each([ 'btnPrev', 'btnNext' ], function(index, btn) {
      if ( o[btn] ) {
        o['$' + btn] = $.isFunction( o[btn] ) ? o[btn].call( div[0] ) : $( o[btn] );

        o['$' + btn].bind('click.jc', function() {
          var step = index === 0 ? curr-o.scroll : curr+o.scroll;
          return go( step );
        });
      }
    });

    if (!o.circular) {
      if (o.btnPrev && start === 0) {
        o.$btnPrev.addClass(o.btnDisabledClass);
      }

      if ( o.btnNext && start + o.visible >= itemLength ) {
        o.$btnNext.addClass(o.btnDisabledClass);
      }
    }

    if (o.btnGo) {
      $.each(o.btnGo, function(i, val) {
        $(val).bind('click.jc', function() {
          return go(o.circular ? o.visible+i : i);
        });
      });
    }
    if (o.mouseWheel && div.mousewheel) {
      div.bind('mousewheel.jc', function(e, d) {
        return d > 0 ? go(curr-o.scroll) : go(curr+o.scroll);
      });
    }

    if (o.pause) {
      div.bind('mouseenter.jc', function() {
        div.trigger('pauseCarousel.jc');
      }).bind('mouseleave.jc', function() {
        div.trigger('resumeCarousel.jc');
      });
    }

    if (o.auto) {
      advancer();
    }

    function vis() {
      return li.slice(curr).slice(0,v);
    }

    function go(to) {
      if (running) { return false; }
      var direction = to > curr;
      if (o.beforeStart) {
        o.beforeStart.call(this, vis(), direction);
      }
      // If circular we are in first or last, then goto the other end
      if (o.circular) {
        // If first, then goto last
        if (to <= start - v - 1) {
          ul.css( animCss, -( (itemLength - (v*2) ) * liSize ) + "px" );
          // If "scroll" > 1, then the "to" might not be equal to the condition; it can be lesser depending on the number of elements.
          curr = to == start - v - 1 ? itemLength-(v*2) - 1 : itemLength-(v*2)-o.scroll;
        } else if (to>=itemLength-v+1) { // If last, then goto first
          ul.css(animCss, -( v * liSize ) + "px" );

          // If "scroll" > 1, then the "to" might not be equal to the condition; it can be greater depending on the number of elements.
          curr = (to == itemLength - v + 1) ? v + 1 : v + o.scroll;
        } else {
          curr = to;
        }

      // If non-circular and to points beyond first or last, we change to first or last.
      } else {
        // Disable buttons when the carousel reaches the last/first, and enable when not
        o.$btnPrev.toggleClass(o.btnDisabledClass, o.btnPrev && to <= 0);
        o.$btnNext.toggleClass(o.btnDisabledClass, o.btnNext && to > itemLength-v);

        if (to<0) {
          curr = 0;
        } else if  (to>itemLength-v) {
          curr = itemLength-v;
        } else {
          curr = to;
        }
      }

      running = true;
      aniProps[animCss] = -(curr*liSize);

      ul.animate(aniProps, o.speed, o.easing, function() {
        if (o.afterEnd) {
          o.afterEnd.call(this, vis(), direction);
        }
        running = false;
      });
      return false;
    } // end go function

    // bind custom events so they can be triggered by user
    div
    .bind('go.jc', function(e, to) {
      if (typeof to == 'undefined') {
        to = '+=1';
      }

      var todir = typeof to == 'string' && /(\+=|-=)(\d+)/.exec(to);

      if ( todir ) {
        to = todir[1] == '-=' ? curr - todir[2] * 1 : curr + todir[2] * 1;
      } else {
        to += start;
      }
      go(to);
    })
    .bind('startCarousel.jc', function(event) {
      clearTimeout(self.setAutoAdvance);
      div.trigger('go', '+=' + o.scroll);
      advancer();
      div.removeData('pausedjc').removeData('stoppedjc');
    })
    .bind('resumeCarousel.jc', function(event, forceRun) {
      clearTimeout(self.setAutoAdvance);
      var stopped = div.data('stoppedjc');
      if ( forceRun || !stopped ) {
        advancer();
        div.removeData('pausedjc');
        if (stopped) {
          div.removeData('stoppedjc');
        }
      }
    })

    .bind('pauseCarousel.jc', function(event) {
      clearTimeout(self.setAutoAdvance);
      div.data('pausedjc', true);
    })
    .bind('stopCarousel.jc', function(event) {
      clearTimeout(self.setAutoAdvance);
      div.data('stoppedjc', true);
    })

    .bind('endCarousel.jc', function() {
      if (self.setAutoAdvance) {
        clearTimeout(self.setAutoAdvance);
      }
      if (o.btnPrev) {
        o[$btnPrev].addClass(o.btnDisabledClass).unbind('.jc');
      }
      if (o.btnNext) {
        o[$btnNext].addClass(o.btnDisabledClass).unbind('.jc');
      }
      if (o.btnGo) {
        $.each(o.btnGo, function(i, val) {
          $(val).unbind('.jc');
        });
      }
      if (self.setAutoAdvance) {
        self.setAutoAdvance = null;
      }
      div.removeData('pausedjc').removeData('stoppedjc');
      div.unbind('.jc');
    });
  });

  return this;
};
$.fn.jCarouselLite.defaults = {
  autoCSS: true,
  btnPrev: null,
  btnNext: null,
  btnDisabledClass: 'disabled',
  btnGo: null,
  mouseWheel: false,

  speed: 200,
  easing: null,
  auto: false, // true to enable auto scrolling
  autoStop: false, // number of times before autoscrolling will stop. (if circular is false, won't iterate more than number of items)
  timeout: 4000, // milliseconds between scrolls
  pause: true, // pause scrolling on hover

  vertical: false,
  circular: true, // continue scrolling when reach the last item
  visible: 3,
  start: 0, // index of item to show initially in the first posiition
  scroll: 1, // number of items to scroll at a time

  beforeStart: null,
  afterEnd: null
};

function css(el, prop) {
  return parseInt($.css(el[0], prop), 10) || 0;
}
function width(el) {
  return  el[0].offsetWidth + css(el, 'marginLeft') + css(el, 'marginRight');
}
function height(el) {
  return el[0].offsetHeight + css(el, 'marginTop') + css(el, 'marginBottom');
}
function iterations(itemLength, options) {
  return options.autoStop && (options.circular ? options.autoStop : Math.min(itemLength, options.autoStop));
}
})(jQuery);