// tipsy, facebook style tooltips for jquery
// version 1.0.0a
// (c) 2008-2010 jason frame [jason@onehackoranother.com]
// released under the MIT license

(function($) {
    
    function maybeCall(thing, ctx) {
        return (typeof thing == 'function') ? (thing.call(ctx)) : thing;
    };
    
    function Tipsy(element, options) {
        this.$element = $(element);
        this.options = options;
        this.enabled = true;
        this.fixTitle();
    };
    
    Tipsy.prototype = {
        show: function() {
            var title = this.getTitle(),
                to_render = title;
            if (title && this.enabled) {
                var $tip = this.tip();

                if(this.cached_title){
                    title = this.cached_title;
                }
                else {
                    this.fetchData();
                }

                $tip.find('.tipsy-inner')[this.options.html ? 'html' : 'text'](title); 
                $tip[0].className = 'tipsy'; // reset classname in case of dynamic gravity
                $tip.remove().css({top: 0, left: 0, visibility: 'hidden', display: 'block'}).prependTo(document.body);
               

                if (this.options.className) {
                    $tip.addClass(maybeCall(this.options.className, this.$element[0]));
                }

                var that = this;
                function tipOver() {
                    that.hoverTooltip = true;
                }
                function tipOut() {
                    if (that.hoverState == 'in') return;  // If field is still focused.
                    that.hoverTooltip = false;
                    if (that.options.trigger != 'manual') {
                        var eventOut = that.options.trigger == 'hover' ? 'mouseleave.tipsy' : 'blur.tipsy';
                        that.$element.trigger(eventOut);
                    }
                }

                if (this.options.hoverable) {
                    $tip.hover(tipOver, tipOut);
                }
                
                var pos = $.extend({}, this.$element.offset(), {
                    width: this.$element[0].offsetWidth,
                    height: this.$element[0].offsetHeight
                });
                
                var actualWidth = $tip[0].offsetWidth,
                    actualHeight = $tip[0].offsetHeight,
                    gravity = maybeCall(this.options.gravity, this.$element[0]);
                
                var tp;
                switch (gravity.charAt(0)) {
                    case 'n':
                        tp = {top: pos.top + pos.height + this.options.offset, left: pos.left + pos.width / 2 - actualWidth / 2};
                        break;
                    case 's':
                        tp = {top: pos.top - actualHeight - this.options.offset, left: pos.left + pos.width / 2 - actualWidth / 2};
                        break;
                    case 'e':
                        tp = {top: pos.top + pos.height / 2 - actualHeight / 2, left: pos.left - actualWidth - this.options.offset};
                        break;
                    case 'w':
                        tp = {top: pos.top + pos.height / 2 - actualHeight / 2, left: pos.left + pos.width + this.options.offset};
                        break;
                }
                
                if (gravity.length == 2) {
                    if (gravity.charAt(1) == 'w') {
                        tp.left = pos.left + pos.width / 2 - 15;
                    } else {
                        tp.left = pos.left + pos.width / 2 - actualWidth + 15;
                    }
                }
                
                $tip.css(tp).addClass('tipsy-' + gravity);
                $tip.find('.tipsy-arrow')[0].className = 'tipsy-arrow tipsy-arrow-' + gravity.charAt(0);
                
                if (this.options.fade) {
                    $tip.stop().css({opacity: 0, display: 'block', visibility: 'visible'}).animate({opacity: this.options.opacity});
                } else {
                    $tip.css({visibility: 'visible', opacity: this.options.opacity});
                }
                // if there's a callback, run it
                if( $.isFunction(this.options.afterShow) ) this.options.afterShow.apply(self);
            }
        },
        hide: function() {
            if (this.options.fade) {
                this.tip().stop().fadeOut(function() { $(this).remove(); });
            } else {
                this.tip().remove();
            }
        },
        
        fixTitle: function() {
            var $e = this.$element;
            if ($e.attr('title') || typeof($e.attr('original-title')) != 'string') {
                $e.attr('original-title', $e.attr('title') || '').removeAttr('title');
            }
        },
        fetchData: function(){
            var o = this.options, 
                tipsy = this,
                url = o.url;

            if(o.url && !this.fetching){
                if (typeof o.url === 'function') {
                    url = url(this.$element);
                }
                $.get(url, {}, function(data){
                    tipsy.cached_title = data;
                    tipsy.fetching = true;
                    if(tipsy.$tip.is(':visible')){
                        tipsy.show();
                    }
                });
            }
        },
        getTitle: function() {
            var title, $e = this.$element, o = this.options;
            this.fixTitle();
            var title, o = this.options;
            if (typeof o.title === 'string') {
                title = $e.attr(o.title == 'title' ? 'original-title' : o.title);
            } else if (typeof o.title == 'function') {
                title = o.title.call($e[0]);
            }
            title = ('' + title).replace(/(^\s*|\s*$)/, "");
            return title || o.fallback;
        },
        
        tip: function() {
            if (!this.$tip) {
                this.$tip = $('<div class="tipsy"></div>').html('<div class="tipsy-arrow"></div><div class="tipsy-inner"></div>');
            }
            return this.$tip;
        },
        
        validate: function() {
            if (!this.$element[0].parentNode) {
                this.hide();
                this.$element = null;
                this.options = null;
            }
        },
        
        enable: function() { this.enabled = true; },
        disable: function() { this.enabled = false; },
        toggleEnabled: function() { this.enabled = !this.enabled; }
    };
    
    $.fn.tipsy = function(options) {
        
        if (options === true) {
            return this.data('tipsy');
        } else if (typeof options == 'string') {
            var tipsy = this.data('tipsy');
            if (tipsy) tipsy[options]();
            return this;
        }
        
        options = $.extend({}, $.fn.tipsy.defaults, options);
        if (options.hoverable) {
            options.delayOut = options.delayOut || 200;
        }
        
        function get(ele) {
            var tipsy = $.data(ele, 'tipsy');
            if (!tipsy) {
                tipsy = new Tipsy(ele, $.fn.tipsy.elementOptions(ele, options));
                $.data(ele, 'tipsy', tipsy);
            }
            return tipsy;
        }
        
        function enter() {
            var tipsy = get(this);
            if( options.activeTip === undefined ){
                tipsy.hoverState = 'in';
                if (options.delayIn == 0) {
                    tipsy.show();
                } else {
                    tipsy.fixTitle();
                    setTimeout(function() { if (tipsy.hoverState == 'in') tipsy.show(); }, options.delayIn);
                }
            }
        };
        
        function leave() {
            var tipsy = get(this);
            if( tipsy.clickState !== 'on' ){
                tipsy.hoverState = 'out';
                if (options.delayOut == 0) {
                    tipsy.hide();
                } else {
                    setTimeout(function() { if (tipsy.hoverState == 'out' && !tipsy.hoverTooltip) tipsy.hide(); }, options.delayOut);
                }
            }
        };
        
        function sticky() {
            var tipsy = get(this),
                activeTip,
                show = (tipsy.clickState === 'on') ? false : true;
            handleClose();

            if( show ){
                tipsy.show();
                tipsy.clickState = 'on';
                options.activeTip = this;
                $(this).addClass('tipsy-sticky-click');
                options.stickyClick(this, tipsy.clickState);
            }
        }

        function handleScroll(event) {
            var target = $(event.target);

            if( !(target.parents().hasClass('tipsy-inner')) ){
                if( options.activeTip ){
                    if(options.closeOnScroll){
                        handleClose();
                    }
                    else {
                        get(options.activeTip).show();
                    }

                }
            }
        }

        function closeAll(){
            var elements = $('.tipsy');

            elements.remove();
        }

        function handleClose(){
            var elements = $('.tipsy-sticky-click'),
                i, length, tipsy, node;

            for(i=0, length = elements.length; i < length; i += 1){
                node = elements[i];
                $(node).removeClass('tipsy-sticky-click');
                tipsy = get(node);
                tipsy.clickState = 'off';
                tipsy.hide();
                options.stickyClick(node, tipsy.clickState);
            }
            options.activeTip = undefined;
        }

        if (!options.live) this.each(function() { get(this); });
        
        if (options.trigger != 'manual') {
            var binder   = options.live ? 'live' : 'bind',
                eventIn  = options.trigger == 'hover' ? 'mouseenter.tipsy' : 'focus.tipsy',
                eventOut = options.trigger == 'hover' ? 'mouseleave.tipsy' : 'blur.tipsy';
            this[binder](eventIn, enter)[binder](eventOut, leave);
        }
        
        if (options.stickyClick) {
            this['live']('click', sticky);
            $(document).bind('scroll', handleScroll);
            $(document).bind('close.tipsy', handleClose);
        }

        $(document).bind('close.tipsy', function(){
            closeAll();  
        });

        return this;
        
    };
    
    $.fn.tipsy.defaults = {
        className: null,
        delayIn: 0,
        delayOut: 0,
        fade: false,
        fallback: '',
        gravity: 'n',
        html: false,
        live: false,
        hoverable: false,
        stickyClick: false,
        offset: 0,
        opacity: 0.8,
        title: 'title',
        trigger: 'hover',
        afterShow: null //call back after the tip is shown
    };
    
    // Overwrite this method to provide options on a per-element basis.
    // For example, you could store the gravity in a 'tipsy-gravity' attribute:
    // return $.extend({}, options, {gravity: $(ele).attr('tipsy-gravity') || 'n' });
    // (remember - do not modify 'options' in place!)
    $.fn.tipsy.elementOptions = function(ele, options) {
        return $.metadata ? $.extend({}, options, $(ele).metadata()) : options;
    };
    
    $.fn.tipsy.autoNS = function() {
        return $(this).offset().top > ($(document).scrollTop() + $(window).height() / 2) ? 's' : 'n';
    };
    
    $.fn.tipsy.autoWE = function() {
        return $(this).offset().left > ($(document).scrollLeft() + $(window).width() / 2) ? 'e' : 'w';
    };
    
    /**
     * yields a closure of the supplied parameters, producing a function that takes
     * no arguments and is suitable for use as an autogravity function like so:
     *
     * @param margin (int) - distance from the viewable region edge that an
     *        element should be before setting its tooltip's gravity to be away
     *        from that edge.
     * @param prefer (string, e.g. 'n', 'sw', 'w') - the direction to prefer
     *        if there are no viewable region edges effecting the tooltip's
     *        gravity. It will try to vary from this minimally, for example,
     *        if 'sw' is preferred and an element is near the right viewable 
     *        region edge, but not the top edge, it will set the gravity for
     *        that element's tooltip to be 'se', preserving the southern
     *        component.
     */
     $.fn.tipsy.autoBounds = function(margin, prefer) {
		return function() {
			var dir = {ns: prefer[0], ew: (prefer.length > 1 ? prefer[1] : false)},
			    boundTop = $(document).scrollTop() + margin,
			    boundLeft = $(document).scrollLeft() + margin,
			    $this = $(this);

			if ($this.offset().top < boundTop) dir.ns = 'n';
			if ($this.offset().left < boundLeft) dir.ew = 'w';
			if ($(window).width() + $(document).scrollLeft() - $this.offset().left < margin) dir.ew = 'e';
			if ($(window).height() + $(document).scrollTop() - $this.offset().top < margin) dir.ns = 's';

			return dir.ns + (dir.ew ? dir.ew : '');
		}
	};
    
})(jQuery);