var nbsp = 160;	
var node_text = 3;
var emptyString = /^\s*$/ ;
var global_valfield;
function trim(str)
{
  return str.replace(/^\s+|\s+$/g, '');
}

function setFocusDelayed()
{
  global_valfield.focus();
}

function setfocus(valfield)
{
  // save valfield in global variable so value retained when routine exits
  global_valfield = valfield;
  setTimeout( 'setFocusDelayed()', 100 );
}

function msg(fld,     // id of element to display message in
             msgtype, // class to give element ("warn" or "error")
             message) // string to display
{
  // setting an empty string can give problems if later set to a 
  // non-empty string, so ensure a space present. (For Mozilla and Opera one could 
  // simply use a space, but IE demands something more, like a non-breaking space.)
  var dispmessage;
  if (emptyString.test(message)) 
    dispmessage = String.fromCharCode(nbsp);    
  else  
    dispmessage = message;

  var elem = document.getElementById(fld);
  elem.firstChild.nodeValue = dispmessage;  
  
  elem.className = msgtype;   // set the CSS class to adjust appearance of message
}

// --------------------------------------------
//            common_check
// Common code for all validation routines to:
// (a) check for older / less-equipped browsers
// (b) check if empty fields are required
// Returns true (validation passed), 
//         false (validation failed) or 
//         proceed (don't know yet)
// --------------------------------------------

var proceed = 2;  

function common_check    (valfield,   // element to be validated
                         infofield,  // id of element to receive info/error msg
                         required)   // true if required
{
  if (!document.getElementById) 
    return true;  // not available on this browser - leave validation to the server
  var elem = document.getElementById(infofield);
  if (!elem.firstChild) return true;  // not available on this browser 
  if (elem.firstChild.nodeType != node_text) return true;  // infofield is wrong type of node  

  if (emptyString.test(valfield.value)) {
    if (required) {
      msg (infofield, "error", "ERROR: required");  
      setfocus(valfield);
      return false;
    }
    else {
      msg (infofield, "warn", "");   // OK
      return true;  
    }
  }
  return proceed;
}

// --------------------------------------------
//            validatePresent
// Validate if something has been entered
// Returns true if so 
// --------------------------------------------

function validatePresent(valfield,   // element to be validated
                         infofield ) // id of element to receive info/error msg
{
  var stat = commonCheck (valfield, infofield, true);
  if (stat != proceed) return stat;

  msg (infofield, "warn", "");  
  return true;
}


// AGE
function validate_age    (valfield,   // element to be validated
                         infofield,  // id of element to receive info/error msg
                         required)   // true if required
{
  var stat = common_check (valfield, infofield, required);
  if (stat != proceed) return stat;

  var tfld = trim(valfield.value);
  var age_re =/^1?[0-9]{1,2}$/
  if (!age_re.test(tfld)) {
    msg (infofield, "error", "ERROR: not a valid age");
    setfocus(valfield);
    return false;
  }

  if (tfld>=130) {
    msg (infofield, "error", "ERROR: you're too old for exercise!");
    setfocus(valfield);
    return false;
  }

  if (tfld>100) msg (infofield, "warn", "Older than 100: check correct");
  else {
    if (tfld<7) msg (infofield, "warn", "Bit young for this, aren't you?");
    else        msg (infofield, "warn", "");
  }
  return true;
}

// WAIST
function validate_wst    (valfield,   // element to be validated
                         infofield,  // id of element to receive info/error msg
                         required)   // true if required
{
  var stat = common_check (valfield, infofield, required);
  if (stat != proceed) return stat;

  var tfld = trim(valfield.value);
  var wst_re =/^[1-6][0-9][.]?[0-9]?$/
  if (!wst_re.test(tfld)) {
    msg (infofield, "error", "ERROR: not a valid waist size");
    setfocus(valfield);
    return false;
  }

  if (tfld>=70) {
    msg (infofield, "error", "ERROR: maximum waist size is 70");
    setfocus(valfield);
    return false;
  }

  if (tfld>55) msg (infofield, "warn", "Waist above 55 inches: double check entry");
  else {
    if (tfld<17) msg (infofield, "warn", "Are you really that thin?");
    else        msg (infofield, "warn", "");
  }
  return true;
}

// FEET
function validate_ft    (valfield,   // element to be validated
                         infofield,  // id of element to receive info/error msg
                         required)   // true if required
{
  var stat = common_check (valfield, infofield, required);
  if (stat != proceed) return stat;

  var tfld = trim(valfield.value);
  var ft_re =/^[4-7]$/
  if (!ft_re.test(tfld)) {
    msg (infofield, "error", "ERROR: not a valid height (feet)");
    setfocus(valfield);
    return false;
  }

  if (tfld>6) msg (infofield, "warn", "Are you really that tall?");
  else {
      msg (infofield, "warn", "");
  }
  return true;
}

// INCHES
function validate_inch    (valfield,   // element to be validated
                         infofield,  // id of element to receive info/error msg
                         required)   // true if required
{
  var stat = common_check (valfield, infofield, required);
  if (stat != proceed) return stat;

  var tfld = trim(valfield.value);
  
  var inch_re =/^[0-1]?[0-9]\.?[0-9]?$/
  if (!inch_re.test(tfld)) {
    msg (infofield, "error", "ERROR: not a valid height (inches)");
    setfocus(valfield);
    return false;
  }

  if (tfld>11.9) { msg (infofield, "error", "ERROR: too many inches!");
    setfocus(valfield);
    return false;
  } else {
  	msg (infofield, "error", "")
  }
}

// MINS
function validate_mins    (valfield,   // element to be validated
                         infofield,  // id of element to receive info/error msg
                         required)   // true if required
{
  var stat = common_check (valfield, infofield, required);
  if (stat != proceed) return stat;

  var tfld = trim(valfield.value);
  
  var mins_re =/^[1-9][0-9]{0,2}$/
  if (!mins_re.test(tfld)) {
    msg (infofield, "error", "ERROR: number of minutes must be an integer between 1 and 499");
    setfocus(valfield);
    return false;
  }
  
   else if (tfld>499) { msg (infofield, "error", "ERROR: minutes must be less than 500.");
    setfocus(valfield);
    return false;
  } else {
  	msg (infofield, "error", "All minutes entries valid")
  }
}

// WEIGHT
function validate_lbs    (valfield,   // element to be validated
                         infofield,  // id of element to receive info/error msg
                         required)   // true if required
{
  var stat = common_check (valfield, infofield, required);
  if (stat != proceed) return stat;

  var tfld = trim(valfield.value);
  
  var lbs_re =/^[0-9]{1,3}$/
  if (!lbs_re.test(tfld)) {
    msg (infofield, "error", "ERROR: not a valid weight.");
    setfocus(valfield);
    return false;
  }

  if (tfld>699) { msg (infofield, "error", "ERROR: sorry, maximum weight for this chart is 699 lbs.");
    setfocus(valfield);
    return false;
  } else {
  	msg (infofield, "error", "")
  }
    if (tfld<40) { msg (infofield, "error", "ERROR: sorry, minimum weight for this chart is 40 lbs.");
    setfocus(valfield);
    return false;
  } else {
  	msg (infofield, "error", "")
  }
}
function validate_kg    (valfield,   // element to be validated
                         infofield,  // id of element to receive info/error msg
                         required)   // true if required
{
  var stat = common_check (valfield, infofield, required);
  if (stat != proceed) return stat;

  var tfld = trim(valfield.value);
  
  var kg_re =/^[0-9]{2,3}.?[0-9]?$/
  if (!kg_re.test(tfld)) {
    msg (infofield, "error", "ERROR: not a valid weight.");
    setfocus(valfield);
    return false;
  }

  if (tfld>499) { msg (infofield, "error", "ERROR: sorry, maximum weight for this chart is 499 kg.");
    setfocus(valfield);
    return false;
  } else {
  	msg (infofield, "error", "")
  }
    if (tfld<25) { msg (infofield, "error", "ERROR: sorry, minimum weight for this chart is 25kg.");
    setfocus(valfield);
    return false;
  } else {
  	msg (infofield, "error", "")
  }
}
// DAYS
function validate_days    (valfield,   // element to be validated
                         infofield,  // id of element to receive info/error msg
                         required)   // true if required
{
  var stat = common_check (valfield, infofield, required);
  if (stat != proceed) return stat;

  var tfld = trim(valfield.value);
  
  var days_re =/^[0-7]\.?[0-9]?$/
  if (!days_re.test(tfld)) {
    msg (infofield, "error", "ERROR: number of days is invalid.");
    setfocus(valfield);
    return false;
   } else {
  	msg (infofield, "error", "")
  }

  if (days>7) { msg (infofield, "error", "ERROR: There aren't but 7 days in a week!");
    setfocus(valfield);
    return false;
  } else {
  	msg (infofield, "error", "")
  }
}

// INTENSITY
function validate_intens    (valfield,   // element to be validated
                         infofield,  // id of element to receive info/error msg
                         required)   // true if required
{
  var stat = common_check (valfield, infofield, required);
  if (stat != proceed) return stat;

  var tfld = trim(valfield.value);
  
  var intens_re =/^[1-9]\.?[0-9]?$/
  if ((!intens_re.test(tfld)) || (tfld>10)) {
    msg (infofield, "error", "ERROR: Intensity must be an integer or single decimal between 1 and 10");
    setfocus(valfield);
    return false;
  } else {
  	msg (infofield, "error", "All intensity entries valid")
  }

}