// This series of functions provide common form field validation.  
// You customize the "validateForm" function to make calls to the following functions 
// with your form fields.  
// If the validation fails, the functions will alert the user with a message and put 
// the text input focus on the field with the error.

// validRequired(formField, fieldLabel) 
// -- checks for a field being empty

// validEmail(formField, fieldLabel, required) 
// -- checks for a correctly formatted email address

// validNum(formField, fieldLabel, required) 
// -- checks for a valid number (a string where all the characters are digits)

// validInt(formField, fieldLabel, required) 
// -- checks for a number (integer) that can be correctly parsed with the function parseInt

// validDate(formField, fieldLabel, required) 
// -- checks for a correctly formatted date 

// The parameters to these functions are defined as:

// formField -- the document reference to your form field (e.g., myform.fieldName)
// fieldLabel -- the user friendly string that you want the error message to refer to your field by
// required -- whether the field is required to be filled in by the user (true/false) 
// To add to your form, add the onsubmit handler to the form tag as shown in the example code.

// <form method="post" action="blformvalidate.htm" onsubmit="return validateForm(this)" id=form1 name=form1>
//   <p>Name: <input name="name" size="32" ><br>
//   Email Address: <input name="email" size="32" ><br>
//   Date Available: <input name="available" size="16" ><i>(mm/dd/yyyy)<br>
//   </i>Years of Experience: <input name="yearsexperience" size="4" ></p>
//   <p><input type="submit"
//   value="Submit" name="submit"></p>
// </form>  
  


function isEmailAddr(email)
{
  var result = false;
  var theStr = new String(email);
  var index = theStr.indexOf("@");
  if (index > 0)
  {
    var pindex = theStr.indexOf(".",index);
    if ((pindex > index+1) && (theStr.length > pindex+1))
    {
      result = true;
    }
  }
  return result;
}

function validRequired(formField,fieldLabel)
{
  var result = true;
  
  if (formField.value == "")
  {
    alert('Please enter a value for the "' + fieldLabel +'" field.');
    formField.focus();
    result = false;
  }
  
  return result;
}

function allDigits(str)
{
  return inValidCharSet(str,"0123456789");
}

function inValidCharSet(str,charset)
{
  var result = true;

  // Note: doesn't use regular expressions to avoid early Mac browser bugs  
  for (var i=0;i<str.length;i++)
  {
    if (charset.indexOf(str.substr(i,1))<0)
    {
      result = false;
      break;
    }
  }
  
  return result;
}

function validEmail(formField,fieldLabel,required)
{
  var result = true;
  
  if (required && !validRequired(formField,fieldLabel))
  {
    result = false;
  }

  if (result && ((formField.value.length < 3) || !isEmailAddr(formField.value)) )
  {
    alert("Please enter a complete email address in the form: yourname@yourdomain.com");
    formField.focus();
    result = false;
  }
   
  return result;

}

function validNum(formField,fieldLabel,required)
{
  var result = true;

  if (required && !validRequired(formField,fieldLabel))
  {
    result = false;
  }
  
  if (result)
  {
    if (!allDigits(formField.value))
    {
      alert('Please enter a number for the "' + fieldLabel +'" field.');
      formField.focus();    
      result = false;
    }
  } 
  
  return result;
}


function validInt(formField,fieldLabel,required)
{
  var result = true;

  if (required && !validRequired(formField,fieldLabel))
  {
    result = false;
  }
  
  if (result)
  {
    var num = parseInt(formField.value,10);
    if (isNaN(num))
    {
      alert('Please enter a number for the "' + fieldLabel +'" field.');
      formField.focus();    
      result = false;
    }
  } 
  
  return result;
}


function validDate(formField,fieldLabel,required)
{
  var result = true;

  if (required && !validRequired(formField,fieldLabel))
  {
    result = false;
  }
  
  if (result)
  {
    var elems = formField.value.split("/");
     
    result = (elems.length == 3); // should be three components
     
    if (result)
    {
      var month = parseInt(elems[0],10);
      var day = parseInt(elems[1],10);
      var year = parseInt(elems[2],10);
      result = allDigits(elems[0]) && (month > 0) && (month < 13) &&
               allDigits(elems[1]) && (day > 0) && (day < 32) &&
               allDigits(elems[2]) && ((elems[2].length == 2) || (elems[2].length == 4));
    }
     
    if (!result)
    {
      alert('Please enter a date in the format MM/DD/YYYY for the "' + fieldLabel +'" field.');
      formField.focus();    
    }
  } 
  
  return result;
}

function validateForm(theForm)
{
  // Customize these calls for your form

  // Start ------->
  if (!validRequired(theForm.name,"Name"))
    return false;

  if (!validEmail(theForm.email,"Email Address",true))
    return false;

  if (!validRequired(theForm.phone,"Phone"))
    return false;

  if (!validRequired(theForm.veriword,"Verification Code"))
    return false;

  //if (!validDate(theForm.available,"Date Available",true))
  //  return false;

  //if (!validNum(theForm.yearsexperience,"Years Experience",true))
  //  return false;
  // <--------- End
  
  return true;
}