function CheckBoxGroup() {
  this.controlBox=null;
  this.controlBoxChecked=null;
  this.maxAllowed=null;
  this.maxAllowedMessage=null;
  this.masterBehavior="all";
  this.formRef=null;
  this.checkboxWildcardNames=new Array();
  this.checkboxNames=new Array();
  this.totalBoxes=0;
  this.totalSelected=0;
  // Public methods
  this.setControlBox=CBG_setControlBox;
  this.setMaxAllowed=CBG_setMaxAllowed;
  this.setMasterBehavior=CBG_setMasterBehavior;  // all, some
  this.addToGroup=CBG_addToGroup;
  // Private methods
  this.expandWildcards=CBG_expandWildcards;
  this.addWildcardCheckboxes=CBG_addWildcardCheckboxes;
  this.addArrayCheckboxes=CBG_addArrayCheckboxes;
  this.addSingleCheckbox=CBG_addSingleCheckbox;
  this.check=CBG_check;
  }
  
CheckBoxGroup.$VERSION = 1.01;

// Set the master control checkbox name
function CBG_setControlBox(name) { this.controlBox=name; }

// Set the maximum number of checked boxes in the set, and optionally
// the message to popup when the max is reached.
function CBG_setMaxAllowed(num,msg) {
  this.maxAllowed=num;
  if (msg!=null&&msg!="") { this.maxAllowedMessage=msg; }
  }

// Set the behavior for the checkbox group master checkbox
//  All: all boxes must be checked for the master to be checked
//  Some: one or more of the boxes can be checked for the master to be checked
function CBG_setMasterBehavior(b) { this.masterBehavior = b.toLowerCase(); }

// Add checkbox wildcards to the checkboxes array
function CBG_addToGroup() {
  if (arguments.length>0) {
    for (var i=0;i<arguments.length;i++) {
      this.checkboxWildcardNames[this.checkboxWildcardNames.length]=arguments[i];
      }
    }
  }

// Expand the wildcard checkbox names given in the addToGroup method
function CBG_expandWildcards() {
  if (this.formRef==null) {alert("ERROR: No form element has been passed.  Cannot extract form name!"); return false; }
  for (var i=0; i<this.checkboxWildcardNames.length;i++) {
    var n = this.checkboxWildcardNames[i];
    var el = this.formRef[n];
    if (n.indexOf("*")!=-1) { this.addWildcardCheckboxes(n); }
    else if(CBG_nameIsArray(el)) { this.addArrayCheckboxes(n); }
    else { this.addSingleCheckbox(el); }
    }
  }


// Add checkboxes to the group which match a pattern
function CBG_addWildcardCheckboxes(name) {
  var i=name.indexOf("*");
  if ((i==0) || (i==name.length-1)) {
    var searchString= (i)?name.substring(0,name.length-1):name.substring(1,name.length);
    var els = this.formRef.elements;
    var l = els.length;
    for (var j=0;j<l;j++) {
      var currentElement = els[j];
      if (currentElement.type && currentElement.type=="checkbox" && currentElement.name) {
        var currentElementName=currentElement.name;
        var partialName = (i)?currentElementName.substring(0,searchString.length) : currentElementName.substring(currentElementName.length-searchString.length,currentElementName.length);
        if (partialName==searchString) {
          if(CBG_nameIsArray(currentElement)) this.addArrayCheckboxes(currentElement);
          else this.addSingleCheckbox(currentElement);
          }
        }
      }
    }
  }

// Add checkboxes to the group which all have the same name
function CBG_addArrayCheckboxes(name) {
  if((CBG_nameIsArray(this.formRef[name])) && (this.formRef[name].length>0)) {
    for (var i=0; i<this.formRef[name].length; i++) { this.addSingleCheckbox(this.formRef[name][i]); }
    }
  }

function CBG_addSingleCheckbox(obj) {
  if (obj != this.formRef[this.controlBox]) {
    this.checkboxNames[this.checkboxNames.length]=obj;
    this.totalBoxes++;
    if (obj.checked) {
      this.totalSelected++;
      }
    }
  }

// Runs whenever a checkbox in the group is clicked
function CBG_check(obj) {
  var checked=obj.checked;
  if (this.formRef==null) {
    this.formRef=obj.form;
    this.expandWildcards();
    if (this.controlBox==null || obj.name!=this.controlBox) {
      this.totalSelected += (checked)?-1:1;
      }
    }
  if (this.controlBox!=null&&obj.name==this.controlBox) {
    if (this.masterBehavior=="all") {
      for (i=0;i<this.checkboxNames.length;i++) { this.checkboxNames[i].checked=checked; }
      this.totalSelected=(checked)?this.checkboxNames.length:0;
      }
    else {
      if (!checked) {
        obj.checked = (this.totalSelected>0)?true:false;
        obj.blur();
        }
      }
    }
  else {
    if (this.masterBehavior=="all" && this.controlBox!=null) {
      if (!checked) {
        this.formRef[this.controlBox].checked=false;
        this.totalSelected--;
        }
      else { this.totalSelected++; }
      if (this.controlBox!=null) {
        this.formRef[this.controlBox].checked=(this.totalSelected==this.totalBoxes)?true:false;
        }
      }
    else {
      if (!obj.checked) { this.totalSelected--; }  
      else { this.totalSelected++; }
      if (this.controlBox!=null) {
        this.formRef[this.controlBox].checked=(this.totalSelected>0)?true:false;
        }
      if (this.maxAllowed!=null) {
        if (this.totalSelected>this.maxAllowed) {
          obj.checked=false;
          this.totalSelected--;
          if (this.maxAllowedMessage!=null) { alert(this.maxAllowedMessage); }
          return false;
          }
        }
      }
    }
  }

function CBG_nameIsArray(obj) {
  return ((typeof obj.type!="string")&&(obj.length>0)&&(obj[0]!=null)&&(obj[0].type=="checkbox"));
  }

function maxlength(element, maxvalue)
     {
     var q = eval("document.surveyform."+element+".value.length");
     var r = q - maxvalue;
     var msg = "Sorry, you have input "+q+" characters into the "+
       "text area box you just completed.\n It can return no more than "+
       maxvalue+" characters to be processed.\n Please abbreviate "+
       "your text by at least "+r+" characters";
     if (maxvalue > 2) {if (q > maxvalue) alert(msg);}
     }

function submit_form() {
document.surveyform.submit();
document.surveyform.reset(); 
}

function checkpcode(TheForm,TheField,TheValue){ //check postcode format is valid

  // Permitted letters depend upon their position in the postcode.
  var alpha1 = "[abcdefghijklmnoprstuwyz]";                       // Character 1
  var alpha2 = "[abcdefghklmnopqrstuvwxy]";                       // Character 2
  var alpha3 = "[abcdefghjkstuw]";                                // Character 3
  var alpha4 = "[abehmnprvwxy]";                                  // Character 4
  var alpha5 = "[abdefghjlnpqrstuwxyz]";                          // Character 5
  

  // Array holds the regular expressions for the valid postcodes
  var pcexp = new Array ();

  // Expression for postcodes: AN NAA, ANN NAA, AAN NAA, and AANN NAA
  pcexp.push (new RegExp ("^(" + alpha1 + "{1}" + alpha2 + "?[0-9]{1,2})(\\s*)([0-9]{1}" + alpha5 + "{2})$","i"));
  
  // Expression for postcodes: ANA NAA
  pcexp.push (new RegExp ("^(" + alpha1 + "{1}[0-9]{1}" + alpha3 + "{1})(\\s*)([0-9]{1}" + alpha5 + "{2})$","i"));

  // Expression for postcodes: AANA  NAA
  pcexp.push (new RegExp ("^(" + alpha1 + "{1}" + alpha2 + "?[0-9]{1}" + alpha4 +"{1})(\\s*)([0-9]{1}" + alpha5 + "{2})$","i"));
  
  // Exception for the special postcode GIR 0AA
  pcexp.push (/^(GIR)(\s*)(0AA)$/i);
  
  // Standard BFPO numbers
  pcexp.push (/^(bfpo)(\s*)([0-9]{1,4})$/i);
  
  // c/o BFPO numbers
  pcexp.push (/^(bfpo)(\s*)(c\/o\s*[0-9]{1,3})$/i);

  // Load up the string to check
  var postCode = TheValue;

  // Assume we're not going to find a valid postcode
  var valid = false;
  
  // Check the string against the types of post codes
  for ( var i=0; i<pcexp.length; i++) {
    if (pcexp[i].test(postCode)) {
    
      // The post code is valid - split the post code into component parts
      pcexp[i].exec(postCode);
      
      // Copy it back into the original string, converting it to uppercase and
      // inserting a space between the inward and outward codes
      postCode = RegExp.$1.toUpperCase() + " " + RegExp.$3.toUpperCase();
      
      // If it is a BFPO c/o type postcode, tidy up the "c/o" part
      postCode = postCode.replace (/C\/O\s*/,"c/o ");
      
      // Load new postcode back into the form element
      valid = true;
      
      // Remember that we have found that the code is valid and break from loop
      break;
    }
  }
  
  // Return with either the reformatted valid postcode or the original invalid 
  // postcode
  
  if (valid) {return postCode;} 
  
  else if (TheValue.length == 0) {return true;}
  else return false;
}

var dFilterStep

function dFilterStrip (dFilterTemp, dFilterMask)
{
    dFilterMask = replace(dFilterMask,'9','');
    for (dFilterStep = 0; dFilterStep < dFilterMask.length++; dFilterStep++)
		{
		    dFilterTemp = replace(dFilterTemp,dFilterMask.substring(dFilterStep,dFilterStep+1),'');
		}
		return dFilterTemp;
}

function dFilterMax (dFilterMask)
{
 		dFilterTemp = dFilterMask;
    for (dFilterStep = 0; dFilterStep < (dFilterMask.length+1); dFilterStep++)
		{
		 		if (dFilterMask.charAt(dFilterStep)!='9')
				{
		        dFilterTemp = replace(dFilterTemp,dFilterMask.charAt(dFilterStep),'');
				}
		}
		return dFilterTemp.length;
}

function dFilter (key, textbox, dFilterMask)
{
		dFilterNum = dFilterStrip(textbox.value, dFilterMask);
		
		if (key==9)
		{
		    return true;
		}
		else if (key==8&&dFilterNum.length!=0)
		{
		 	 	dFilterNum = dFilterNum.substring(0,dFilterNum.length-1);
		}
 	  else if ( ((key>47&&key<58)||(key>95&&key<106)) && dFilterNum.length<dFilterMax(dFilterMask) )
		{
        dFilterNum=dFilterNum+String.fromCharCode(key);
		}

		var dFilterFinal='';
    for (dFilterStep = 0; dFilterStep < dFilterMask.length; dFilterStep++)
		{
        if (dFilterMask.charAt(dFilterStep)=='9')
				{
					  if (dFilterNum.length!=0)
					  {
				        dFilterFinal = dFilterFinal + dFilterNum.charAt(0);
					      dFilterNum = dFilterNum.substring(1,dFilterNum.length);
					  }
				    else
				    {
				        dFilterFinal = dFilterFinal + "";
				    }
				}
		 		else if (dFilterMask.charAt(dFilterStep)!='9')
				{
				    dFilterFinal = dFilterFinal + dFilterMask.charAt(dFilterStep); 			
				}
//		    dFilterTemp = replace(dFilterTemp,dFilterMask.substring(dFilterStep,dFilterStep+1),'');
		}


		textbox.value = dFilterFinal;
    return false;
}

function replace(fullString,text,by) {
// Replaces text with by in string
    var strLength = fullString.length, txtLength = text.length;
    if ((strLength == 0) || (txtLength == 0)) return fullString;

    var i = fullString.indexOf(text);
    if ((!i) && (text != fullString.substring(0,txtLength))) return fullString;
    if (i == -1) return fullString;

    var newstr = fullString.substring(0,i) + by;

    if (i+txtLength < strLength)
        newstr += replace(fullString.substring(i+txtLength,strLength),text,by);

    return newstr;
}


//  End -->