; (function($) {

    $.fn.carousel = function(params) {

        var params = $.extend({
            direction: "horizontal",
            loop: false,
            dispItems: 1,
            pagination: false,
            paginationPosition: "inside",
            nextBtn: "<span>Next</span>",
            prevBtn: "<span>Previous</span>",
            btnsPosition: "inside",
            nextBtnInsert: "appendTo",
            prevBtnInsert: "prependTo",
            autoSlide: false,
            autoSlideInterval: 3000,
            delayAutoSlide: 3000,
            combinedClasses: false,
            effect: "slide",
            slideEasing: "swing",
            animSpeed: "normal",
            equalWidths: "true",
            callback: function() { }
        }, params);

        if (params.btnsPosition == "outside") {
            params.prevBtnInsert = "insertBefore";
            params.nextBtnInsert = "insertAfter";
        }

        return this.each(function() {

            // Env object
            var env = {
                $elts: {},
                params: params,
                launchOnLoad: []
            };

            // Carousel main container
            env.$elts.carousel = $(this).addClass("js");

            // Carousel content
            env.$elts.content = $(this).children().css({ position: "absolute", "top": 0 });

            // Content wrapper
            env.$elts.wrap = env.$elts.content.wrap('<div class="carousel-wrap"></div>').parent().css({ overflow: "hidden", position: "relative" });

            // env.steps object
            env.steps = {
                first: 0, // First step
                count: env.$elts.content.find(">*").length // Items count
            };

            // Last visible step
            env.steps.last = env.steps.count - 1;

            // Next / Prev Buttons
            env.$elts.prevBtn = $(params.prevBtn)[params.prevBtnInsert](env.$elts.carousel).addClass("carousel-control previous carousel-previous").data("firstStep", -(env.params.dispItems));
            env.$elts.nextBtn = $(params.nextBtn)[params.nextBtnInsert](env.$elts.carousel).addClass("carousel-control next carousel-next").data("firstStep", env.params.dispItems);

            // Bind events on next / prev buttons
            initButtonsEvents(env, function(e) {
                slide(e, this, env);
            });

            // Pagination
            if (env.params.pagination) initPagination(env);

            // On document+css load !
            $(function() {

                // First item
                var $firstItem = env.$elts.content.find(">*:eq(0)");

                // Width 1/1 : Get default item width
                env.itemWidth = $firstItem.outerWidth();

                // Width 2/3 : Define content width

                if (params.direction == "vertical") {
                    env.contentWidth = env.itemWidth;
                } else {
                    if (params.equalWidths) {
                        env.contentWidth = env.itemWidth * env.steps.count;
                    } else {
                        env.contentWidth = (function() {
                            var totalWidth = 0;

                            env.$elts.content.find(">*").each(function() {
                                totalWidth += $(this).outerWidth();
                            });

                            return totalWidth;
                        })();
                    }
                }

                // Width 3/3 : Set content width to container
                env.$elts.content.width(env.contentWidth);

                // Height 1/2 : Get default item height
                env.itemHeight = $firstItem.outerHeight();

                // Height 2/2 : Set content height to container
                if (params.direction == "vertical") {
                    env.$elts.content.css({ height: env.itemHeight * env.steps.count + "px" });
                    env.$elts.content.parent().css({ height: env.itemHeight * env.params.dispItems + "px" });
                } else {
                    env.$elts.content.parent().css({ height: env.itemHeight });
                }

                // Update Next / Prev buttons state
                updateButtonsState(env);

                // Launch function added to "document ready" event
                $.each(env.launchOnLoad, function(i, fn) {
                    fn();
                });

                // Launch autoslide
                if (env.params.autoSlide) {
                    window.setTimeout(function() {
                        env.autoSlideInterval = window.setInterval(function() {
                            env.$elts.nextBtn.click();
                        }, env.params.autoSlideInterval);
                    }, env.params.delayAutoSlide);
                }

            });

        });

    };

    // Slide effect
    function slide(e, btn, env) {
        var $btn = $(btn);
        var newFirstStep = $btn.data("firstStep");

        env.params.callback(newFirstStep);

        // Effect
        switch (env.params.effect) {

            // No effect 
            case "no":
                if (env.params.direction == "vertical") {
                    env.$elts.content.css("top", -(env.itemHeight * newFirstStep) + "px");
                } else {
                    env.$elts.content.css("left", -(env.itemWidth * newFirstStep) + "px");
                }
                break;

            // Fade effect 
            case "fade":
                if (env.params.direction == "vertical") {
                    env.$elts.content.hide().css("top", -(env.itemHeight * newFirstStep) + "px").fadeIn(env.params.animSpeed);
                } else {
                    env.$elts.content.hide().css("left", -(env.itemWidth * newFirstStep) + "px").fadeIn(env.params.animSpeed);
                }
                break;

            // Slide effect 
            default:
                if (env.params.direction == "vertical") {
                    env.$elts.content.stop().animate({
                        top: -(env.itemHeight * newFirstStep) + "px"
                    }, env.params.animSpeed, env.params.slideEasing);
                } else {
                    env.$elts.content.stop().animate({
                        left: -(env.itemWidth * newFirstStep) + "px"
                    }, env.params.animSpeed, env.params.slideEasing);
                }
        }

        env.steps.first = newFirstStep;

        updateButtonsState(env);

        // Stop autoslide
        if (!!e.clientX && env.autoSlideInterval) {
            window.clearInterval(env.autoSlideInterval);
        }
    };

    // Update all buttons state : disabled or not
    function updateButtonsState(env) {

        env.$elts.prevBtn.data("firstStep", env.steps.first - env.params.dispItems);
        env.$elts.nextBtn.data("firstStep", env.steps.first + env.params.dispItems);

        if (env.$elts.prevBtn.data("firstStep") < 0) {

            if (env.params.loop && env.steps.count > env.params.dispItems) {
                env.$elts.prevBtn.data("firstStep", env.steps.count - env.params.dispItems);
                env.$elts.prevBtn.trigger("enable");
            } else {
                env.$elts.prevBtn.trigger("disable");
            }

        } else {
            env.$elts.prevBtn.trigger("enable");
        }

        if (env.$elts.nextBtn.data("firstStep") >= env.steps.count) {

            if (env.params.loop && env.steps.count > env.params.dispItems) {
                env.$elts.nextBtn.data("firstStep", 0);
                env.$elts.nextBtn.trigger("enable");
            } else {
                env.$elts.nextBtn.trigger("disable");
            }

        } else {
            env.$elts.nextBtn.trigger("enable");
        }

        if (env.params.pagination) {
            env.$elts.paginationBtns.removeClass("active")
			.filter(function() { return ($(this).data("firstStep") == env.steps.first) }).addClass("active");
        }
    };

    // Next / Prev buttons events only
    function initButtonsEvents(env, slideEvent) {

        env.$elts.nextBtn.add(env.$elts.prevBtn)
		.bind("enable", function() {
		    var $this = $(this).bind("click", slideEvent).removeClass("disabled");
		    // Combined classes : IE6 compatibility
		    if (env.params.combinedClasses) {
		        $this.removeClass("next-disabled previous-disabled");
		    }
		})
		.bind("disable", function() {
		    var $this = $(this).unbind("click").addClass("disabled");

		    // Combined classes : IE6 compatibility
		    if (env.params.combinedClasses) {

		        if ($this.is(".next")) {
		            $this.addClass("next-disabled");

		        } else if ($this.is(".previous")) {
		            $this.addClass("previous-disabled");

		        }
		    }
		});

        env.$elts.nextBtn.add(env.$elts.prevBtn).hover(
			function() {
			    $(this).addClass("hover");
			},
			function() {
			    $(this).removeClass("hover");
			}
		);
    };

    // Pagination
    function initPagination(env) {
        env.$elts.pagination = $('<div class="center-wrap"><div class="carousel-pagination"><p></p></div></div>')[((env.params.paginationPosition == "outside") ? "insertAfter" : "appendTo")](env.$elts.carousel).find("p");

        env.$elts.paginationBtns = $([]);

        env.$elts.content.find("li").each(function(i) {
            if (i % env.params.dispItems == 0) {
                env.$elts.paginationBtns = env.$elts.paginationBtns.add($('<a role="button"><span>' + (env.$elts.paginationBtns.length + 1) + '</span></a>').data("firstStep", i));
            }
        });

        env.$elts.paginationBtns.appendTo(env.$elts.pagination);

        env.$elts.paginationBtns.slice(0, 1).addClass("active");

        // Events
        env.launchOnLoad.push(function() {
            env.$elts.paginationBtns.click(function(e) {
                slide(e, this, env);
            });
        });
    };

})(jQuery);