// JavaScript Document

function checkform ( form )
{
  // ** START **
var noimage=1;
  
  if (form.CBModelos.value == "0") {
    alert( "Please enter a vehicle." );
    form.CBModelos.focus();
    return false ;
  }    
  
  if (form.Location.value == "") {
    alert( "Please enter a location." );
    form.Location.focus();
    return false ;
  }    
  
	if (form.CIUDAD.value == "") {
		alert( "Please enter the city of the image." );
		form.CIUDAD.focus();
		return false ;
	}    
 	
	if (isDate(form.FECHA.value)==false){
		//alert( "Please enter the date." );
		form.FECHA.focus()
		return false
	} 
  
	if (form.NAME.value == "") {
		alert( "Please enter your name or nickname." );
		form.NAME.focus();
		return false ;
	}
  
  
 //CHECK EMAIL
  	validRegExp = /^[^@]+@[^@]+.[a-z]{2,}$/i;
 	strEmail = form.MAIL.value;
   // search email text for regular exp matches
    if (strEmail.search(validRegExp) == -1) 
   {
      alert('Please enter your email address.');
	  form.MAIL.focus();
      return false;
    } 

//CHECK PHOTOS
	for(var i=1;i<=3;i++)
	{
		var fldname="FILE"+i;
		if(eval("form."+fldname).value!="")
		{
			var ext = eval("form."+fldname).value;
			ext = ext.substring(ext.length-3,ext.length);
			ext = ext.toLowerCase();
			if(ext != 'jpg' && ext != 'gif' && ext != 'png') {
				alert('You selected a .'+ext+' file; please select a .jpg, .gif or .png file instead!');
				//eval("form.FILE"+i).focus();
			return false; }
			noimage=0;
		}
	}

	if(noimage==1)
	{
		alert("Please Upload atleast 1 Photo");
		return false;
	}
 

  // ** END **
  return true ;
}


// Código variado para gestión de fechas
// Declaring valid date character, minimum year and maximum year
var dtCh= "/";
var minYear=1900;
var maxYear=2100;

function isInteger(s){
	var i;
    for (i = 0; i < s.length; i++){   
        // Check that current character is number.
        var c = s.charAt(i);
        if (((c < "0") || (c > "9"))) return false;
    }
    // All characters are numbers.
    return true;
}

function stripCharsInBag(s, bag){
	var i;
    var returnString = "";
    // Search through string's characters one by one.
    // If character is not in bag, append to returnString.
    for (i = 0; i < s.length; i++){   
        var c = s.charAt(i);
        if (bag.indexOf(c) == -1) returnString += c;
    }
    return returnString;
}

function daysInFebruary (year){
	// February has 29 days in any year evenly divisible by four,
    // EXCEPT for centurial years which are not also divisible by 400.
    return (((year % 4 == 0) && ( (!(year % 100 == 0)) || (year % 400 == 0))) ? 29 : 28 );
}
function DaysArray(n) {
	for (var i = 1; i <= n; i++) {
		this[i] = 31
		if (i==4 || i==6 || i==9 || i==11) {this[i] = 30}
		if (i==2) {this[i] = 29}
   } 
   return this
}

function isDate(dtStr){
	var daysInMonth = DaysArray(12)
	var pos1=dtStr.indexOf(dtCh)
	var pos2=dtStr.indexOf(dtCh,pos1+1)
	var strMonth=dtStr.substring(0,pos1)
	var strDay=dtStr.substring(pos1+1,pos2)
	var strYear=dtStr.substring(pos2+1)
	strYr=strYear
	if (strDay.charAt(0)=="0" && strDay.length>1) strDay=strDay.substring(1)
	if (strMonth.charAt(0)=="0" && strMonth.length>1) strMonth=strMonth.substring(1)
	for (var i = 1; i <= 3; i++) {
		if (strYr.charAt(0)=="0" && strYr.length>1) strYr=strYr.substring(1)
	}
	month=parseInt(strMonth)
	day=parseInt(strDay)
	year=parseInt(strYr)
	if (pos1==-1 || pos2==-1){
		alert("The date format should be : mm/dd/yyyy")
		return false
	}
	if (strMonth.length<1 || month<1 || month>12){
		alert("Please enter a valid month")
		return false
	}
	if (strDay.length<1 || day<1 || day>31 || (month==2 && day>daysInFebruary(year)) || day > daysInMonth[month]){
		alert("Please enter a valid day")
		return false
	}
	if (strYear.length != 4 || year==0 || year<minYear || year>maxYear){
		alert("Please enter a valid 4 digit year between "+minYear+" and "+maxYear)
		return false
	}
	if (dtStr.indexOf(dtCh,pos2+1)!=-1 || isInteger(stripCharsInBag(dtStr, dtCh))==false){
		alert("Please enter a valid date")
		return false
	}
return true
}