/* global window, document, jquery */
(function($) {
$.fn.flipster = function(options) {
    var ismethodcall = typeof options === 'string' ? true : false;

    if (ismethodcall) {
        var method = options;
        var args = array.prototype.slice.call(arguments, 1);
    } else {
        var defaults = {
            itemcontainer:    'ul', // container for the flippin' items.
            itemselector:     'li', // selector for children of itemcontainer to flip
            style:            'coverflow', // switch between 'coverflow' or 'carousel' display styles
            start:            'center', // starting item. set to 0 to start at the first, 'center' to start in the middle or the index of the item you want to start with.
            
            enablekeyboard:   true, // enable left/right arrow navigation
            enablemousewheel: true, // enable scrollwheel navigation (up = left, down = right)
            enabletouch:      true, // enable swipe navigation for touch devices
            
            onitemswitch:     $.noop, // callback function when items are switched
            disablerotation:  false,

            enablenav:        false, // if true, flipster will insert an unordered list of the slides
            navposition:      'before', // [before|after] changes the position of the navigation before or after the flipsterified items - case-insensitive

            enablenavbuttons: false, // if true, flipster will insert previous / next buttons
            prevtext:         'previous',       // changes the text for the previous button
            nexttext:         'next'            // changes the text for the next button
        };
        var settings = $.extend({}, defaults, options);

        var win = $(window);
    }

    return this.each(function(){

        var _flipster = $(this);
        var methods;

        if (ismethodcall) {
            methods = _flipster.data('methods');
            return methods[method].apply(this, args);
        }

        var _flipitemsouter;
        var _flipitems;
        var _flipnav;
        var _flipnavitems;
        var _current = 0;
        
        var _starttouchx = 0;
        var _actionthrottle = 0;
        var _throttletimeout;
        var compatibility;

        // public methods
        methods = {
            jump: jump
        };
        _flipster.data('methods', methods);

        function removethrottle() {
            _actionthrottle = 0;
        }

        function resize() {
            _flipitemsouter.height(calculatebiggestflipitemheight());
            _flipster.css("height","auto");
            if ( settings.style === 'carousel' ) { _flipitemsouter.width(_flipitems.width()); }
        }

        function calculatebiggestflipitemheight() {
            var biggestheight = 0;
            _flipitems.each(function() {
                if ($(this).height() > biggestheight) biggestheight = $(this).height();
            });
            return biggestheight;
        }

        function buildnav() {
            if ( settings.enablenav && _flipitems.length > 1 ) {
                var navcategories = [],
                    navitems = [],
                    navlist = [];

                _flipitems.each(function(){
                    var category = $(this).data("flip-category"),
                        itemid = $(this).attr("id"),
                        itemtitle = $(this).attr("title");

                    if ( typeof category !== 'undefined' ) {
                        if ( $.inarray(category,navcategories) < 0 ) {
                            navcategories.push(category);
                            navlist[category] = '<li class="flip-nav-category"><a href="#" class="flip-nav-category-link" data-flip-category="'+category+'">'+category+'</a>\n<ul class="flip-nav-items">\n';
                        }
                    }

                    if ( $.inarray(itemid,navitems) < 0 ) {
                        navitems.push(itemid);
                        var link = '<a href="#'+itemid+'" class="flip-nav-item-link">'+itemtitle+'</a></li>\n';
                        if ( typeof category !== 'undefined' ) {
                            navlist[category] = navlist[category] + '<li class="flip-nav-item">' + link;
                        }
                        else {
                            navlist[itemid] = '<li class="flip-nav-item no-category">' + link;
                        }
                    }
                });

                var navdisplay = '<ul class="flipster-nav">\n';
                for (var catindex in navcategories) {
                    navlist[navcategories[catindex]] = navlist[navcategories[catindex]] + "</ul>\n</li>\n";
                }
                for (var navindex in navlist) {
                    navdisplay += navlist[navindex];
                }
                navdisplay += '</ul>';

                if(settings.navposition.tolowercase() != "after") {
                    _flipnav = $(navdisplay).prependto(_flipster);
                } else {
                    _flipnav = $(navdisplay).appendto(_flipster);
                }

                _flipnavitems = _flipnav.find("a").on("click",function(e){
                    var target;
                    if ( $(this).hasclass("flip-nav-category-link") ) {
                        target = _flipitems.filter("[data-flip-category='"+$(this).data("flip-category")+"']");
                    } else {
                        target = $(this.hash);
                    }
                    
                    if ( target.length ) {
                        jump(target);
                        e.preventdefault();
                    }
                });
            }
        }

        function updatenav() {
            if ( settings.enablenav && _flipitems.length > 1 ) {
                var currentitem = $(_flipitems[_current]);
                _flipnav.find(".flip-nav-current").removeclass("flip-nav-current");
                _flipnavitems.filter("[href='#"+currentitem.attr("id")+"']").addclass("flip-nav-current");
                _flipnavitems.filter("[data-flip-category='"+currentitem.data("flip-category")+"']").parent().addclass("flip-nav-current");
            }
        }

        function buildnavbuttons() {
            if ( settings.enablenavbuttons && _flipitems.length > 1 ) {
                _flipster.find(".flipto-prev, .flipto-next").remove();
                _flipster.append("<a href='#' class='flipto-prev'>"+settings.prevtext+"</a> <a href='#' class='flipto-next'>"+settings.nexttext+"</a>");
                
                _flipster.children('.flipto-prev').on("click", function(e) {
                    jump("left");
                    e.preventdefault();
                });
                
                _flipster.children('.flipto-next').on("click", function(e) {
                    jump("right");
                    e.preventdefault();
                });
            }
        }

        function center() {
            var currentitem = $(_flipitems[_current]).addclass("flip-current");
            
            _flipitems.removeclass("flip-prev flip-next flip-current flip-past flip-future no-transition");

            if ( settings.style === 'carousel' ) {
                
                _flipitems.addclass("flip-hidden");

                var nextitem = $(_flipitems[_current+1]),
                    futureitem = $(_flipitems[_current+2]),
                    previtem = $(_flipitems[_current-1]),
                    pastitem = $(_flipitems[_current-2]);

                if ( _current === 0 ) {
                    previtem = _flipitems.last();
                    pastitem = previtem.prev();
                }
                else if ( _current === 1 ) {
                    pastitem = _flipitems.last();
                }
                else if ( _current === _flipitems.length-2 ) {
                    futureitem = _flipitems.first();
                }
                else if ( _current === _flipitems.length-1 ) {
                    nextitem = _flipitems.first();
                    futureitem = $(_flipitems[1]);
                }

                futureitem.removeclass("flip-hidden").addclass("flip-future");
                pastitem.removeclass("flip-hidden").addclass("flip-past");
                nextitem.removeclass("flip-hidden").addclass("flip-next");
                previtem.removeclass("flip-hidden").addclass("flip-prev");

            }
            else {
                var spacer = currentitem.outerwidth()/2;
                var totalleft = 0;
                var totalwidth = _flipitemsouter.width();
                var currentwidth = currentitem.outerwidth();
                var currentleft = (_flipitems.index(currentitem)*currentwidth)/2 +spacer/2;

                _flipitems.removeclass("flip-hidden");

                for (var i = 0; i < _flipitems.length; i++) {
                    var thisitem = $(_flipitems[i]);
                    var thiswidth = thisitem.outerwidth();

                    if (i < _current) {
                        thisitem.addclass("flip-past")
                            .css({
                                "z-index" : i,
                                "left" : (i*thiswidth/2)+"px"
                            });
                    }
                    else if ( i > _current ) {
                        thisitem.addclass("flip-future")
                            .css({
                                "z-index" : _flipitems.length-i,
                                "left" : (i*thiswidth/2)+spacer+"px"
                            });
                    }
                }

                currentitem.css({
                    "z-index" : _flipitems.length+1,
                    "left" : currentleft +"px"
                });

                totalleft = (currentleft + (currentwidth/2)) - (totalwidth/2);
                var newleftpos = -1*(totalleft)+"px";
                /* untested compatibility */
                if (compatibility) {
                    var leftitems = $(".flip-past");
                    var rightitems = $(".flip-future");
                    $(".flip-current").css("zoom", "1.0");
                    for (i = 0; i < leftitems.length; i++) {
                        $(leftitems[i]).css("zoom", (100-((leftitems.length-i)*5)+"%"));
                    }
                    for (i = 0; i < rightitems.length; i++) {
                        $(rightitems[i]).css("zoom", (100-((i+1)*5)+"%"));
                    }

                    _flipitemsouter.animate({"left":newleftpos}, 333);
                }
                else {
                    _flipitemsouter.css("left", newleftpos);
                }
            }

            currentitem
                .addclass("flip-current")
                .removeclass("flip-prev flip-next flip-past flip-future flip-hidden");

            resize();
            updatenav();
            settings.onitemswitch.call(this);
        }
        
        function jump(to) {
            if ( _flipitems.length > 1 ) {
                if ( to === "left" ) {
                    if ( _current > 0 ) { _current--; }
                    else { _current = _flipitems.length-1; }
                }
                else if ( to === "right" ) {
                    if ( _current < _flipitems.length-1 ) { _current++; }
                    else { _current = 0; }
                } else if ( typeof to === 'number' ) {
                    _current = to;
                } else {
                    // if object is sent, get its index
                    _current = _flipitems.index(to);
                }
                center();
            }
        }

        function init() {
            // basic setup
            _flipster.addclass("flipster flipster-active flipster-"+settings.style).css("visibility","hidden");
            if (settings.disablerotation)
              _flipster.addclass('no-rotate');
            _flipitemsouter = _flipster.find(settings.itemcontainer).addclass("flip-items");
            _flipitems = _flipitemsouter.find(settings.itemselector).addclass("flip-item flip-hidden").wrapinner("<div class='flip-content' />");

            //browsers that don't support css3 transforms get compatibility:
            var isiemax8 = ('\v' === 'v'); //ie <= 8
            var checkie = document.createelement("b");
            checkie.innerhtml = "<!--[if ie 9]><i></i><![endif]-->"; //ie 9
            var isie9 = checkie.getelementsbytagname("i").length === 1;
            if (isiemax8 || isie9) {
                compatibility = true;
                _flipitemsouter.addclass("compatibility");
            }

            // insert navigation if enabled.
            buildnav();
            buildnavbuttons();

            // set the starting item
            if (settings.start && _flipitems.length > 1) {
                // find the middle item if start = center
                if ( settings.start === 'center' ) {
                    if (!_flipitems.length % 2) {
                        _current = _flipitems.length/2 + 1;
                    } else {
                        _current = math.floor(_flipitems.length/2);
                    }
                } else {
                    _current = settings.start;
                }
            }


            // initialize containers
            resize();

            // necessary to start flipster invisible and then fadein so height/width can be set accurately after page load
            _flipster.hide().css("visibility","visible").fadein(400,function(){ center(); });

            // attach event bindings.
            win.on("resize.flipster", function() { 
                resize(); 
                center(); 
            });

            // navigate directly to an item by clicking
            _flipitems.on("click", function(e) {
                if ( !$(this).hasclass("flip-current") ) { e.preventdefault(); }
                jump(_flipitems.index(this));
            });

            // keyboard navigation
            if (settings.enablekeyboard && _flipitems.length > 1) {
                win.on("keydown.flipster", function(e) {
                    _actionthrottle++;
                    if (_actionthrottle % 7 !== 0 && _actionthrottle !== 1) return; //if holding the key down, ignore most events
                    
                    var code = e.which;
                    if (code === 37 ) {
                        e.preventdefault();
                        jump('left');
                    } else if (code === 39 ) {
                        e.preventdefault();
                        jump('right');
                    }
                });
        
                win.on("keyup.flipster", function(e){
                    _actionthrottle = 0; //reset action throttle on key lift to avoid throttling new interactions
                });
            }

            // mousewheel navigation
            if (settings.enablemousewheel && _flipitems.length > 1) { // todo: fix scrollwheel on firefox
                _flipster.on("mousewheel.flipster", function(e){
                    _throttletimeout = window.settimeout(removethrottle, 500); //throttling should expire if scrolling pauses for a moment.
                    _actionthrottle++;
                    if (_actionthrottle % 4 !==0 && _actionthrottle !== 1) return; //throttling like with held-down keys
                    window.cleartimeout(_throttletimeout);
                    
                    if ( e.originalevent.wheeldelta /120 > 0 ) { jump("left"); }
                    else { jump("right"); }
                    
                    e.preventdefault();
                });
            }

            // touch navigation
            if ( settings.enabletouch && _flipitems.length > 1 ) {
                _flipster.on("touchstart.flipster", function(e) {
                    _starttouchx = e.originalevent.targettouches[0].screenx;
                });

                _flipster.on("touchmove.flipster", function(e) {
                    e.preventdefault();
                    var nowx = e.originalevent.targettouches[0].screenx;
                    var touchdiff = nowx-_starttouchx;
                    if (touchdiff > _flipitems[0].clientwidth/1.75){
                        jump("left");
                        _starttouchx = nowx;
                    }else if (touchdiff < -1*(_flipitems[0].clientwidth/1.75)){
                        jump("right");
                        _starttouchx = nowx;
                    }
                });

                _flipster.on("touchend.flipster", function(e) {
                    _starttouchx = 0;
                });
            }
        }

        // initialize if flipster is not already active.
        if ( !_flipster.hasclass("flipster-active") ) { init(); }
    });
};
})(jquery);