function Pager(tableName, itemsPerPage) {
    this.tableName = tableName;
    this.itemsPerPage = itemsPerPage;
    this.currentPage = 1;
    this.pages = 1;
    this.inited = false;
    
    this.showRecords = function(from, to) {        
        var rows = document.getElementById(tableName).rows;
        // i starts from 1 to skip table header row
		//*changed to 0 to start without header
        for (var i = 0; i < rows.length; i++) {
            if (i < from || i > to)  
                rows[i].style.display = 'none';
            else
                rows[i].style.display = '';
        }
    }
    
    this.showPage = function(pageNumber) {
    	if (! this.inited) {
    		alert("not inited");
    		return;
    	}

        var oldPageAnchor = document.getElementById('pg'+this.currentPage);
        oldPageAnchor.className = 'pg-normal';
        
        this.currentPage = pageNumber;
        var newPageAnchor = document.getElementById('pg'+this.currentPage);
        newPageAnchor.className = 'pg-selected';
        // uncomment this if you started without header
        //var from = (pageNumber - 1) * itemsPerPage + 1;
		// comment this to start with a header
		var from = (pageNumber - 1) * itemsPerPage
        var to = from + itemsPerPage - 1;
        this.showRecords(from, to);
								
								var pgNext = document.getElementById('pgNext');
        var pgPrev = document.getElementById('pgPrev');
        if (this.currentPage == this.pages)
            pgNext.style.display = 'none';
        else
            pgNext.style.display = '';
	if (this.currentPage == 1)
            pgPrev.style.display = 'none';
        else
            pgPrev.style.display = '';

								
								
    }   
    
    this.prev = function() {
        if (this.currentPage > 1)
            this.showPage(this.currentPage - 1);
    }
    
    this.next = function() {
        if (this.currentPage < this.pages) {
            this.showPage(this.currentPage + 1);
        }
    }                        
    
    this.init = function() {
        var rows = document.getElementById(tableName).rows;
        //var records = (rows.length - 1); 
		var records = (rows.length); 
        this.pages = Math.ceil(records / itemsPerPage);
        this.inited = true;
    }

    this.showPageNav = function(pagerName, positionId) {
    	if (! this.inited) {
    		alert("not inited");
    		return;
    	}
    	var element = document.getElementById(positionId);
    	
    	var pagerHtml = '<span id="pgPrev" onclick="' + pagerName + '.prev();" class="pg-normal"> &#171 Anteriores </span>  ';
        for (var page = 1; page <= this.pages; page++) 
            pagerHtml += '<span id="pg' + page + '" class="pg-normal" onclick="' + pagerName + '.showPage(' + page + ');">' + page + '</span>  ';
        pagerHtml += '<span id="pgNext" onclick="'+pagerName+'.next();" class="pg-normal"> Pr&oacute;ximos &#187;</span>';            
        
        element.innerHTML = pagerHtml;
    }
}