/*
 * jQuery galleryScroll v1.2.1 
 *
 * Copyright (c) 2008 Taranets Aleksey
 * email: aleks_tar@ukr.net
 * Licensed under the MIT License:
 * http://www.opensource.org/licenses/mit-license.php
 */

/*
	************* OPTIONS ************************************** default ****************
	btPrev         - link for previos [selector]    	btPrev: 'a.link-prev'
	btNext         - link for next [selector]		btNext: 'a.link-next'
	holderList     - image list holder [Tag name]		holderList: 'div'
	scrollElParent - list [Tag name]			scrollElParent: 'ul'
	scrollEl       - list element [Tag name]		scrollEl: 'li'
	slideNum       - view slide numbers [boolean]		slideNum: false
	duration       - duration slide [1000 - 1sec]		duration : 1000
	step           - slide step [int]			step: false
	circleSlide    - slide circle [boolean]			circleSlide: true
	disableClass   - class for disable link			disableClass: 'disable'
	funcOnclick    - callback function			funcOnclick: null
	*************************************************************************************
*/
jQuery.fn.galleryScroll = function(_options) {
    // defaults options	
    var _options = jQuery.extend({
        btPrev: 'a.link-prev',
        btNext: 'a.link-next',
        holderList: 'div',
        scrollElParent: 'ul',
        scrollEl: 'li',
        slideNum: false,
        duration: 1000,
        step: false,
        circleSlide: true,
        disableClass: 'disable',
        funcOnclick: null,
        pages: null
    }, _options);

    return this.each(function() {
        var _this = $(this);

        var _gWidth = jQuery(_options.holderList, _this).get(0).offsetWidth;
        var _liWidth = jQuery(_options.scrollEl, _this).get(0).offsetWidth;
        var _liSum = jQuery(_options.scrollEl, _this).length * _liWidth;
        var _margin = 0;
        var f = 0;
        var _step = 0;
        if (!_options.step) _step = _gWidth; else _step = _options.step * _liWidth;

        if (!_options.circleSlide) {
            jQuery(_options.btPrev, _this).addClass(_options.disableClass);
        }
        if (_options.slideNum && !_options.step) {
            var _lastSection = 0;
            var _sectionWidth = 0;
            while (_sectionWidth < _liSum) {
                _sectionWidth = _sectionWidth + _gWidth;
                if (_sectionWidth > _liSum) {
                    _lastSection = _sectionWidth - _liSum;
                }
            }
        }
        // dlr: move page [direction: 1 = next | -1 = previous]
        jQuery.fn.galleryScroll.movePage = function(direction) {
            var _nextPath = "/our_work/", _curPath = location.pathname.toLowerCase(), _npIdx;
            if (_options.pages != null && _options.pages.length > 0) {
                for (var _cpIdx = 0; _cpIdx < _options.pages.length; _cpIdx++) {
                    if (_options.pages[_cpIdx].toLowerCase() == _curPath) {
                        _npIdx = (_cpIdx + direction);
                        _npIdx = (_npIdx < 0) ? (_options.pages.length - 1) : (_npIdx == _options.pages.length ? 0 : _npIdx);
                        _nextPath = _options.pages[_npIdx];
                    }
                }
            }
            location.href = _nextPath + (direction == -1 ? "#<" : "");
        };
        // dlr: move page [direction: 1 = next | -1 = previous]
        jQuery.fn.galleryScroll.last = function() {
            //alert(_margin + "\n" + _liSum + "\n" + _gWidth);
            _margin = _liSum - _gWidth;
            //jQuery(_options.scrollElParent, _this).animate({ marginLeft: -_margin + "px" }, { queue: false, duration: 0 });
            jQuery(_options.scrollElParent, _this).css("marginLeft", -_margin + "px");
            f = (_margin == 0 ? 0 : 1); // dlr
        };
        // click button 'Next'
        jQuery(_options.btNext, _this).click(function() {
            var _singleSlide = (_liSum - _gWidth == 0); // dlr
            jQuery(_options.btPrev, _this).removeClass(_options.disableClass);
            if (_liSum - _gWidth <= _margin + _step) {
                if (f == 0 && !_singleSlide) {
                    _margin = _liSum - _gWidth;
                    f = 1;
                    if (!_options.circleSlide)
                        jQuery(this).addClass(_options.disableClass);
                }
                else {
                    if (_options.circleSlide) {
                        if (_options.pages != null && _options.pages.length > 0) { // dlr
                            jQuery.fn.galleryScroll.movePage(1);
                        }
                        else {
                            _margin = 0;
                            f = 0;
                        }
                    }
                }
            } else _margin = _margin + _step;

            jQuery(_options.scrollElParent, _this).animate({ marginLeft: -_margin + "px" }, { queue: false, duration: _options.duration });

            if (_options.slideNum && !_options.step) jQuery.fn.galleryScroll.numListActive(_margin, _options.slideNum, _gWidth, _lastSection);
            if (jQuery.isFunction(_options.funcOnclick)) {
                _options.funcOnclick.apply(_this);
            }
            //f = (_margin == 0 ? 0 : 1); // dlr
            return false;
        });
        // click button 'Prev'
        jQuery(_options.btPrev, _this).click(function() {
            jQuery(_options.btNext, _this).removeClass(_options.disableClass);
            if (_margin - _step == -_step) {
                if (!_options.circleSlide) {
                    jQuery(this).addClass(_options.disableClass);
                    _margin = 0;
                } else {
                    if (_options.pages != null && _options.pages.length > 0) { // dlr
                        jQuery.fn.galleryScroll.movePage(-1);
                    }
                    else {
                        _margin = _liSum - _gWidth;
                    }
                }
            }
            else if (_margin - _step < 0 && _margin - _step > -_step) _margin = 0;
            else _margin = _margin - _step;
            if (!_options.circleSlide && _margin == 0) jQuery(this).addClass(_options.disableClass);

            jQuery(_options.scrollElParent, _this).animate({ marginLeft: -_margin + "px" }, { queue: false, duration: _options.duration });

            if (_options.slideNum && !_options.step) jQuery.fn.galleryScroll.numListActive(_margin, _options.slideNum, _gWidth, _lastSection);

            if (jQuery.isFunction(_options.funcOnclick)) {
                _options.funcOnclick.apply(_this);
            }
            //f = (_margin == 0 ? 0 : 1); // dlr
            return false;
        });
        // Number list
        jQuery.fn.galleryScroll.numListCreate = function(_elNumList, _liSumWidth, _width, _section) {
            var _numListElC = '';
            var _num = 1;
            var _difference = _liSumWidth + _section;
            while (_difference > 0) {
                _difference = _difference - _width;
                _numListElC += '<li><a href="">' + _num + '</a></li>';
                _num++;
            }
            $(_elNumList).html('<ul>' + _numListElC + '</ul>');
        };
        jQuery.fn.galleryScroll.numListActive = function(_marginEl, _slideNum, _width, _section) {
            $('a', _slideNum).removeClass('active');
            var _activeRange = _width - _section - 1;
            var _n = 0;
            if (_marginEl != 0) {
                while (_marginEl > _activeRange) {
                    _activeRange = (_n * _width) - _section - 1;
                    _n++;
                }
            }
            var _a = (_activeRange + _section + 1) / _width - 1;
            $('a', _slideNum).eq(_a).addClass('active');
        };
        if (_options.slideNum && !_options.step) {
            jQuery.fn.galleryScroll.numListCreate(_options.slideNum, _liSum, _gWidth, _lastSection);
            jQuery.fn.galleryScroll.numListActive(_margin, _options.slideNum, _gWidth, _lastSection);

            jQuery('a', _options.slideNum).click(function() {
                jQuery(_options.btPrev, _this).removeClass(_options.disableClass);
                jQuery(_options.btNext, _this).removeClass(_options.disableClass);

                var _indexNum = jQuery('a', _options.slideNum).index($(this));
                _margin = _step * _indexNum;
                if (_margin + _step > _liSum) {
                    _margin = _margin - (_margin - _liSum) - _step;
                    if (!_options.circleSlide) jQuery(_options.btNext, _this).addClass(_options.disableClass);
                }
                jQuery(_options.scrollElParent, _this).animate({ marginLeft: -_margin + "px" }, { queue: false, duration: _options.duration });

                if (!_options.circleSlide && _margin == 0) jQuery(_options.btPrev, _this).addClass(_options.disableClass);
                jQuery.fn.galleryScroll.numListActive(_margin, _options.slideNum, _gWidth, _lastSection);
                return false;
            });
        }
        // Look for a back hash
        if (location.hash.toLowerCase() == "#<") {
            jQuery.fn.galleryScroll.last();
        }
    });
}