/**
    Package     : JQuery
    Plugin      : Tab
    Author      : Daniel Simangunsong
    Code Name   : Bugs Fire    
    
    Need JQuery Actual Plugin (http://dreamerslab.com)
 */
 
(function($){   
    $.fn.vslide = function(params) {
        
        var defaults = {
            height      : 473,
            direction   : "up",
            dw_space    : null,
        }        
        
        var params = $.extend( defaults, params );
        // Chainability        
        return this.each (function(){
            var object = $(this);           
            
                        
            // Lets Roll ...            
            var page            = $('#work_page',object);
            var space           = $('.work_space',object);
            var next            = $('.down.cursor',object);
            var prev            = $('.up.cursor',object);
                        
            var allowed_height  = parseInt(params.height);
            var work_space      = parseInt(space.actual('height'));
            
            if (params.dw_space != null) {
                var work_space  = parseInt(params.dw_space);
            }
            var allowed_page    = Math.ceil(work_space/allowed_height);
            var mydir           = params.direction;
            
            
            // Let's reset our button.
            function showhidecursor(work_page) {
                if (work_page == allowed_page) {
                    next.hide();
                };
                if (work_page > 1) {
                    prev.show();
                }
                if (work_page < allowed_page){
                    next.show();
                }
                if (work_page == 1) {
                    prev.hide();
                };
            }
            showhidecursor(1);
            /* */                       
            // Handle Previous and Next Button Click.
            next.click(function(){
                var work_page   = parseInt(page.text());
                var next_page   = work_page+1;
                var interval    = allowed_height*work_page;
                
                showhidecursor(next_page);
                if (mydir=='up') {
                    space.animate({"margin-top": -interval},400);    
                }
                
                page.text(next_page);
            });
            prev.click(function(){
                var work_page   = parseInt(page.text());
                var prev_page   = work_page-1;
                var interval    = allowed_height*prev_page-allowed_height
                ;
                showhidecursor(prev_page);
                if (mydir=='up') {
                    space.animate({"margin-top": -interval},400);    
                }
                page.text(prev_page);
            });
        });
    };
})(jQuery);