var Paging = function(parameters){
    
    var _page_title = 'Page';
    var _page_per_view = 10.0;
    var _rows_per_page = 15;
    var _current_page=1; 
    var _record_count = 0;
    var _goto_page= 'gotoPage';
    var _render_top = null;
    var _render_bottom = null; 
    
    //constructor function
    var _Paging = function(parameters){
        
        if (parameters.page_per_view !=null){
            _page_per_view = parameters.page_per_view;
        }
        
        if (parameters.rows_per_page !=null){
            _rows_per_page = parameters.rows_per_page;
        }
        
        if (parameters.render_top != null){
            _render_top = parameters.render_top;
        }
        
        if (parameters.render_bottom != null){
            _render_bottom = parameters.render_bottom;
        }
        
        if (parameters.record_count > 0){
            _record_count = parameters.record_count; 
        }
        
        if (parameters.current_page){
            _current_page = parameters.current_page; 
        }
        
        if (parameters.on_success){
            _goto_page = parameters.on_success; 
        }
        
        if (parameters.page_title) {
            _page_title = parameters.page_title;   
        }
    }
    
    this.getCurrentPage  = function(){ return _current_page; }
    this.setCurrentPage = function(current_page){ _current_page = current_page };
    
    this.getRecordCount  = function(){ return _record_count; }
    this.setRecordCount = function(record_count){ _record_count = record_count };

    this.getRowsPerPage  = function(){ return _rows_per_page; }
    this.setRowsPerPage = function(rows_per_page){ _rows_per_page = rows_per_page };
    
    this.getGotoPage = function(){ return _goto_page; }
    this.setGotoPage = function(goto_page){ _goto_page = goto_page };
    
    this.getRowStart = function(){ 
        return (_current_page * _rows_per_page) - _rows_per_page + 1;
    }
    
    this.getRowEnd = function(){
        return _current_page * _rows_per_page;
    }
    
    this.getNextPage = function(){ 
        return _current_page  + 1;
    }
    
    this.getPreviousPage = function(){ 
        return _current_page  - 1;
    }

    this.getTotalPages = function(){ 
        
        var result = (_record_count / _rows_per_page) +  (_record_count % _rows_per_page == 0? 0: 1); 
        //var result = _record_count / _page_per_view;
        result = Math.floor(result); 
        //result = parseInt(result,10);    //disregard the decimal points

        return result;
    }
    
    this.getCountStart = function(){ 
        
        var page_no = _current_page;
        
        page_no = parseFloat(page_no); 
        
        page_no = Math.ceil( (page_no / (_page_per_view)))  -1 ;
        
        page_no = (page_no * _page_per_view) + 1;
        
        return page_no ;
        
        //return Math.ceil( (page_no / (_page_per_view))) ;
        
        //return  (((_current_page - 1 )/ _page_per_view) * _page_per_view) + 1 ;
    }
    
    this.getCountEnd = function(){ 
        
        var count_end = this.getCountStart() + _page_per_view;
        
        if(count_end > this.getTotalPages()){
            count_end = Number(this.getTotalPages()) + 1;
        }
        return count_end;
    }
    //Output: [<< < Page 1 2 3 4 5 6 7 8 9 10 11 > >>]            
    this.getPagingStyle2 = function(){
        
        var goto_page = this.getGotoPage();
        var current_page = this.getCurrentPage();
        
        var count_start = this.getCountStart();
        var count_end = this.getCountEnd();
        
        var previous_page = Number(this.getCurrentPage()) - 1;
        var next_page = Number(this.getCurrentPage()) + 1 ; 
        
        var first_page = 1;
        var last_page = this.getTotalPages(); 
        
        var paging ='';
        var link_page='';
        var link_first_page='';
        var link_prev_page='';
        var link_last_page ='';
        var link_next_page=''
        
        var link_param_others = '"' + this.getRecordCount()  + '","' + goto_page + '","' + 
                                _render_top + '","' + _render_bottom + '"';
        
        var params = 'render_top:"' + _render_top + '",' +
                                'render_bottom:"' + _render_bottom + '",' +
                                'goto_page:"' + goto_page + '",' +
                                'record_count:"' + this.getRecordCount()  + '"' ;
                                
        for (var i=count_start; i<count_end;i++){
            
            if (i ==current_page){
                paging  = paging + ' <b class="nrlist-active">' + i + '</b>';
            }else{
                                            
                link_page = 'javascript:' + goto_page + '({on_success:"' + i + '",'+ params +  '})';
                paging  = paging + " <a href='" + link_page + "' class='nrlist'>" + i + "</a>";
            }
        }
        
        
        if (current_page>1){
            link_page = 'javascript:' + goto_page + '({on_success:"' + first_page + '",' + params +  '})';
            
            
            link_first_page = "<a href='" + link_page + "' class='nrlist'><<</a>";
            
            link_page = 'javascript:' + goto_page + '({on_success:"' + previous_page + '",' + params +  '})';
            link_prev_page = "<a href='" + link_page + "' class='nrlist'><</a>";

            //add first and last page
            paging = link_first_page + ' ' + link_prev_page + ' ' +  paging ;
                    
        }
        
        if (current_page !=last_page){
            link_page = 'javascript:' + goto_page + '({on_success:"' + last_page + '",' + params +  '})';
            
            link_last_page = "<a href='" + link_page + "' class='nrlist'>>></a>";
            
            link_page = 'javascript:' + goto_page + '({on_success:"' + next_page + '",' + params +  '})';
            
            link_next_page = "<a href='" + link_page + "' class='nrlist'>></a>";
            
            paging = paging + ' ' + link_next_page + ' ' + link_last_page;

        }
        
        paging = _page_title+' ' + paging;
        
        //render the paging (at the top)
        if (_render_top !=null){
            document.getElementById(_render_top).innerHTML = paging;
        }

        //render the paging (at the bottom)
        //if (_render_bottom !="null"){
        var bottom_page_exist = document.getElementById(_render_bottom);
        if (bottom_page_exist){    
            //alert(_render_bottom);
            document.getElementById(_render_bottom).innerHTML = paging;

        }else{
            //alert(document.getElementById(_render_bottom) );            
        }
    }
        
    //call the constructor
    _Paging(parameters);

    if (_record_count>0){
        this.getPagingStyle2();
    }else{

        if (_render_top){
            document.getElementById(_render_top).innerHTML = ' ';
        }
        
        //render the paging (at the bottom)
        if (_render_bottom){
            document.getElementById(_render_bottom).innerHTML =' ';
        }
    }
    
}