var montly_clicks;
var cpc;
var conversion_rate;
var profit;

$(document).ready(function() {    
    
    $("#monthly_clicks").keyup( function() {

       var val =  $("#monthly_clicks").val();
       
       if (val == "") {
            if (!$("#monthly_click_err").is(":hidden")) $("#monthly_click_err").hide("fast");
            return;        
       }

       var no  = parseInt(val, 10);

       if (!isNaN(no)) {            
            if (!$("#monthly_click_err").is(":hidden")) $("#monthly_click_err").hide("fast");
            montly_clicks = no;
            calculate();            
       }
       else {
            $("#monthly_click_err").text("Error parsing number");
            if ($("#monthly_click_err").is(":hidden")) $("#monthly_click_err").show("fast");
       }
       
    });
    
    $("#cpc").keyup( function () {
        
       var val =  $("#cpc").val();
       
       if (val == "") {
            if (!$("#cpc_err").is(":hidden")) $("#cpc_err").hide("fast");
            return;        
       }

       var no  = parseFloat(val);

       if (!isNaN(no)) {            
            if (!$("#cpc_err").is(":hidden")) $("#cpc_err").hide("fast");
            cpc = no;
            calculate();            
       }
       else {
            $("#cpc_err").text("Error parsing number");
            if ($("#cpc_err").is(":hidden")) $("#cpc_err").show("fast");
       }
        
    });
    
    $("#conversion_rate").keyup( function() {
       var val =  $("#conversion_rate").val();
       
       if (val == "") {
            if (!$("#conversion_rate_err").is(":hidden")) $("#conversion_rate_err").hide("fast");
            return;        
       }

       var no  = parseFloat(val);

       if (!isNaN(no)) {            
            if (!$("#conversion_rate_err").is(":hidden")) $("#conversion_rate_err").hide("fast");
            conversion_rate = no;
            calculate();            
       }
       else {
            $("#conversion_rate_err").text("Error parsing number");
            if ($("#conversion_rate_err").is(":hidden")) $("#conversion_rate_err").show("fast");
       }
        
    });
    
    $("#profit").keyup( function() {

       var val =  $("#profit").val();
       
       if (val == "") {
            if (!$("#profit_err").is(":hidden")) $("#profit_err").hide("fast");
            return;        
       }

       var no  = parseFloat(val);

       if (!isNaN(no)) {            
            if (!$("#profit_err").is(":hidden")) $("#profit_err").hide("fast");
            profit = no;
            calculate();            
       }
       else {
            $("#profit_err").text("Error parsing number");
            if ($("#profit_err").is(":hidden")) $("#profit_err").show("fast");
       }
        
    });
    
    $("#go").click( function() {
        
        var val =  $("#monthly_clicks").val();
        var no  = parseInt(val, 10);
        if (!isNaN(no)) montly_clicks = no;
        
        val =  $("#cpc").val();
        no  = parseFloat(val);
        if (!isNaN(no)) cpc = no;
        
        val =  $("#conversion_rate").val();
        no  = parseFloat(val);
        if (!isNaN(no)) conversion_rate = no;
        
        val =  $("#profit").val();
        no  = parseFloat(val);
        if (!isNaN(no)) profit = no;
        
        calculate();
    })
    
});


function calculate() {
    if (!montly_clicks || !cpc || !conversion_rate || !profit) return;
    
    if ((isNaN( eval(montly_clicks * cpc) )==true))
	var monthlycost=0;
    else
        var monthlycost = eval(montly_clicks * cpc)
    
    if ((isNaN( eval(montly_clicks * (conversion_rate / 100)) )==true))
        var numberofconversions=0;
    else
        var numberofconversions = eval(montly_clicks * (conversion_rate / 100))
    
    if ((isNaN( eval((numberofconversions * profit) - monthlycost) )==true))
            var projectedprofit=0;
    else
            var projectedprofit = eval((numberofconversions * profit) - monthlycost)
    
    if ((monthlycost==0))
        roi=0;
    else
        var roi = eval((projectedprofit / monthlycost)*100);
    
    var result1 = Math.round(monthlycost*100)/100;
    var result2 = Math.round(numberofconversions*100)/100;
    var result3 = Math.round(projectedprofit*100)/100;
    var result4 = Math.round(roi*100)/100;
    
    var html = '<p class="headline bold">Results</p>';
    
    html+='<p>Monthly cost = $'+ result1 +'</p>';
    html+='<p>Number of conversions = ' + result2 +'</p>';
    html+='<p>Projected profit (net of advertising expense) = $' + result3 +'</p>';
    html+='<p>ROI = '+ result4 + "%</p>";   
    
    $("#results").html(html);

}