var Bubble = function() {
    
    var SlideOutBubble = function(bubble) {
        if (!bubble.isDisplayed()) {             
            bubble.enableDisplayMode("block"); 
            bubble.fadeIn();            
        }
    };
    
    var slideInBubble = function(bubble) {
        if (bubble.isDisplayed()) {
            bubble.enableDisplayMode("block"); 
            bubble.fadeOut();
        }
    };
    
    return {
        ShowBubble: function(senderId) {                    
            senderId = senderId.trim();
            bubbleImgId = String.format('bubble{0}', senderId);
            bubbleImg = Utils.Get(bubbleImgId);
            bubbleImg.addClass(bubbleImgId);
            SlideOutBubble(bubbleImg);                                
        },
        
        HideBubble: function(senderId) {
            senderId = senderId.trim();
            bubbleImgId = String.format('bubble{0}', senderId);
            bubbleImg = Utils.Get(bubbleImgId);            
            slideInBubble(bubbleImg); 
        }        
    }
} ();