// JavaScript Document
function addLoadEvent(func) {
  var oldonload = window.onload;
  if (typeof window.onload != 'function') {
    window.onload = func;
  } else {
    window.onload = function() {
      oldonload();
      func();
    }
  }
}

function insertAfter(newElement,targetElement) {
  var parent = targetElement.parentNode;
  if (parent.lastChild == targetElement) {
    parent.appendChild(newElement);
  } else {
    parent.insertBefore(newElement,targetElement.nextSibling);
  }
}

function prepareSearchForm () {
	var form = document.searchForm;
	form.onsubmit = function() {
		return validateSearchForm(this);
	}	
}

function validateSearchForm(whichForm) {
	removeErrorMsg();
	var minPrice = parseInt(whichForm.Minimum_Price.value);
	var maxPrice = parseInt(whichForm.Maximum_Price.value);
	if (minPrice > maxPrice) {
		//alert(minPrice + " is greater than " + maxPrice);
		displayError("searchbutton", "Your Minimum is higher than your Maximum Price. Please select a new range.");
		return false;
	} else if (minPrice == maxPrice) {
		//alert(minPrice + " is the same as " + maxPrice);
		displayError("searchbutton", "Your Minimum is the same as your Maximum Price. Please select a new range.");
		return false;
	}
	return true;
}

function removeErrorMsg() {
	var paras = document.getElementsByTagName("p");
	for (var i=0; i<paras.length; i++) {
		if (paras[i].getAttribute("class") == "errorMsg") {
			paras[i].parentNode.removeChild(paras[i]);
			i--;
		}
	}
}

function displayError(where,msg) {
	if (!document.createElement) return false;
	if (!document.createTextNode) return false;
	if (!document.getElementById) return false;
	var beforeElement = document.getElementById(where);
	var errorMsg = document.createElement("p");
	errorMsg.setAttribute("className","errorMsg");
	errorMsg.setAttribute("class","errorMsg");
	var errorMsgText = document.createTextNode(msg);
	errorMsg.appendChild(errorMsgText);
	insertAfter(errorMsg,beforeElement);
}

addLoadEvent(prepareSearchForm);