function ctrlDisplay() {

	var calcDiv = document.getElementById('calculator');

	if(calcDiv.className == 'shown') calcDiv.className = 'hidden';
	else calcDiv.className = 'shown';

	return true;
}



function hideWindow() {

	var calcDiv = document.getElementById('calculator');
	calcDiv.className = 'hidden';

	return true;
}



var xmlHttp = createXmlHttpRequestObject(); 

function createXmlHttpRequestObject() {	

  var xmlHttp;

  if (window.ActiveXObject) {
    try {xmlHttp = new ActiveXObject("Microsoft.XMLHTTP");}
		catch (e) { xmlHttp = false; }

  } else {
    try { xmlHttp = new XMLHttpRequest(); }
		catch (e) { xmlHttp = false; }
  }

  if (!xmlHttp) alert("No XMLHttpRequest.");
  else return xmlHttp;
}



function getCalculatorResult() {
  if (xmlHttp.readyState == 4
		|| xmlHttp.readyState == 0) {

		var elems = document.forms['calculator'].elements;

		var amount = elems['amount'].value;

		var fromSindex = elems['from'].selectedIndex;
		var from = elems['from'][fromSindex].value;

		var toSindex = elems['to'].selectedIndex;
		var to = elems['to'][toSindex].value;

		var operatorSindex = elems['operator'].selectedIndex;
		var operator = elems['operator'][operatorSindex].value;

		var per = elems['per'].value;


		var params = "";
		params += amount + '|' + from + '|' + to + '|'
			+ operator + '|' + per;

		//alert(params);
		params = "det=" + params;
    xmlHttp.open("post", "/calc-currate/", true);  
		xmlHttp.setRequestHeader("Content-type",
			"application/x-www-form-urlencoded");
		xmlHttp.setRequestHeader("Content-length",
			params.length);
		xmlHttp.setRequestHeader("Connection", "close");

    xmlHttp.onreadystatechange = printCalculatorResult;
    xmlHttp.send(params);
  }
}



function printCalculatorResult() {
  if (xmlHttp.readyState == 4) {
    if (xmlHttp.status == 200) {

			// We'll get JSON from django view
      var calcResult = eval(xmlHttp.responseText);

			// we'll get the form element
      var calcInfo = document.getElementById('calc-info');

			var info = '';

			var amount = calcResult[0]
			var from_name = calcResult[1]
			var from_rate = calcResult[2]
			var to_name = calcResult[3]
			var to_rate = calcResult[4]
			var result = calcResult[5]
			var commission = calcResult[6]
			var result_com = calcResult[7]
			var operator_sign = calcResult[8]

			// Exchange rate of single item
			info += '<p class="item_rate">';
			info += '1 ' + from_name + ' = ' + from_rate;
			info += ' ' + to_name + '<br />';
			info += '1 ' + to_name + ' = ' + to_rate;
			info += ' ' + from_name + '</p>';

			// Result
			info += '<p class="result">';
			info += amount + ' ' + from_name;
			info += ' = ';
			info += result + ' ' + to_name + '</p>'

			if (result_com != 0){
				info += '<p class="commission">';
				info += 'С комиссионными';
				info += ' (' + operator_sign + commission + ')';
				info += ' = ' + result_com + '</p>';
			}

			calcInfo.innerHTML = info;
			calcInfo.className = 'shown';

			// you should write here how to add the result to div

      // restart sequence
      setTimeout('getCalculatorResult()', 30000000);

    } else alert("Проблема с соединением или есть пустые поля");
  }
}




function resetCalculator(){

	document.getElementById('calcform').reset();
	var calcInfo = document.getElementById('calc-info');
	calcInfo.textContent = '';
	calcInfo.className = 'hidden';

	return true;
}