// form validation function //
function validate_contribution(form) {
  var x_cont_first_name = form.x_cont_first_name.value;
  var x_cont_last_name = form.x_cont_last_name.value;
  var x_preferred_phone = form.x_preferred_phone.value;
  var x_email = form.x_email.value;
  var x_address = form.x_address.value;
  var x_city = form.x_city.value;
  var x_state = form.x_state.value;
  var x_zip = form.x_zip.value;
  var x_amount = form.x_amount.value;
  var x_first_name = form.x_first_name.value;
  var x_last_name = form.x_cont_last_name.value;
  var x_card_num = form.x_card_num.value;
  var x_exp_month = form.x_exp_month.value;
  var x_exp_year = form.x_exp_year.value;
  
  var limitedTextRegex = /^[a-zA-Z]+(([\'\,\.\- ][a-zA-Z ])?[a-zA-Z]*)*$/;
  var emailRegex = /^[\w-\.]+@([\w-]+\.)+[\w-]{2,4}$/;
  var textRegex = /<\/?\w+((\s+\w+(\s*=\s*(?:".*?"|'.*?'|[^'">\s]+))?)+\s*|\s*)\/?>/;
  var numRegex = /^\d?$/;
  var intRegex = /^\s*(\+|-)?\d+\s*$/;
  var phoneRegex = /^(?:\([2-9]\d{2}\)\ ?|[2-9]\d{2}(?:\-?|\ ?))[2-9]\d{2}[- ]?\d{4}$/;
  var zipRegex = /^\d{5}(-\d{4})?$/;
  
  if(x_cont_first_name == "") {
    inlineMsg('x_cont_first_name','You must enter your first name.',2);
    return false;
  }
  if(!x_cont_first_name.match(limitedTextRegex)) {
    inlineMsg('x_cont_first_name','You have entered an invalid first name.',2);
    return false;
  }
  
  if(x_cont_last_name == "") {
    inlineMsg('x_cont_last_name','You must enter your last name.',2);
    return false;
  }
  if(!x_cont_last_name.match(limitedTextRegex)) {
    inlineMsg('x_cont_last_name','You have entered an invalid last name.',2);
    return false;
  }
  
  if(x_preferred_phone == "") {
    inlineMsg('x_preferred_phone','You must enter your preferred phone.',2);
    return false;
  }
  if(!x_preferred_phone.match(phoneRegex)) {
    inlineMsg('x_preferred_phone','You have entered an invalid preferred phone.',2);
    return false;
  }
  
  if(x_email == "") {
    inlineMsg('x_email','You must enter your email.',2);
    return false;
  }
  if(!x_email.match(emailRegex)) {
    inlineMsg('x_email','You have entered an invalid email.',2);
    return false;
  }
  
  if(x_city != "" && !x_city.match(limitedTextRegex)) {
    inlineMsg('x_city','You have entered an invalid city.',2);
    return false;
  }
  
  if(x_state != "" && !x_state.match(limitedTextRegex)) {
    inlineMsg('x_state','You have entered an invalid state.',2);
    return false;
  }
  
  if(x_zip != "" && !x_zip.match(zipRegex)) {
    inlineMsg('x_zip','You have entered an invalid zip.',2);
    return false;
  }
  
  if(x_amount == "") {
    inlineMsg('x_amount','You must enter an amount, example "50.00".',2);
    return false;
  }
  if(x_amount.match(intRegex)) {
    inlineMsg('x_amount','You have entered an invalid amount, example "50.00".');
    return false;
  }
  
  if(x_cont_first_name == "") {
    inlineMsg('x_cont_first_name','You must enter your first name.',2);
    return false;
  }
  if(!x_cont_first_name.match(limitedTextRegex)) {
    inlineMsg('x_cont_first_name','You have entered an invalid first name.',2);
    return false;
  }
  
  if(x_last_name == "") {
    inlineMsg('x_last_name','You must enter your last name.',2);
    return false;
  }
  if(!x_last_name.match(limitedTextRegex)) {
    inlineMsg('x_last_name','You have entered an invalid last name.',2);
    return false;
  }
  
  if(x_card_num == "") {
    inlineMsg('x_card_num','You must enter a credit card number.',2);
    return false;
  }
  if(x_card_num.match(numRegex)) {
    inlineMsg('x_card_num','You have entered an invalid credit card number.');
    return false;
  }
  
  if(x_exp_month == "") {
    inlineMsg('x_exp_month','You must enter an expiration month, please enter a two-digit month ex. "01".',2);
    return false;
  }
  if(x_exp_month.match(numRegex)) {
    inlineMsg('x_exp_month','You have entered an invalid expiration month, please enter a two-digit month ex. "01".');
    return false;
  }
  
  if(x_exp_year == "") {
    inlineMsg('x_exp_year','You must enter an expiration year, please enter a two-digit year ex. "11".',2);
    return false;
  }
  if(x_exp_year.match(numRegex)) {
    inlineMsg('x_exp_year','You have entered an invalid expiration year, please enter a two-digit year ex. "11".');
    return false;
  }
  
  return true;
}

// START OF MESSAGE SCRIPT //

var MSGTIMER = 20;
var MSGSPEED = 5;
var MSGOFFSET = 3;
var MSGHIDE = 3;

// build out the divs, set attributes and call the fade function //
function inlineMsg(target,string,autohide) {
  var msg;
  var msgcontent;
  if(!document.getElementById('msg')) {
    msg = document.createElement('div');
    msg.id = 'msg';
    msgcontent = document.createElement('div');
    msgcontent.id = 'msgcontent';
    document.body.appendChild(msg);
    msg.appendChild(msgcontent);
    msg.style.filter = 'alpha(opacity=0)';
    msg.style.opacity = 0;
    msg.alpha = 0;
  } else {
    msg = document.getElementById('msg');
    msgcontent = document.getElementById('msgcontent');
  }
  msgcontent.innerHTML = string;
  msg.style.display = 'block';
  var msgheight = msg.offsetHeight;
  var targetdiv = document.getElementById(target);
  targetdiv.focus();
  var targetheight = targetdiv.offsetHeight;
  var targetwidth = targetdiv.offsetWidth;
  var topposition = topPosition(targetdiv) - ((msgheight - targetheight) / 2);
  var leftposition = leftPosition(targetdiv) + targetwidth + MSGOFFSET;
  msg.style.top = topposition + 'px';
  msg.style.left = leftposition + 'px';
  clearInterval(msg.timer);
  msg.timer = setInterval("fadeMsg(1)", MSGTIMER);
  if(!autohide) {
    autohide = MSGHIDE;  
  }
  window.setTimeout("hideMsg()", (autohide * 1000));
}

// hide the form alert //
function hideMsg(msg) {
  var msg = document.getElementById('msg');
  if(!msg.timer) {
    msg.timer = setInterval("fadeMsg(0)", MSGTIMER);
  }
}

// face the message box //
function fadeMsg(flag) {
  if(flag == null) {
    flag = 1;
  }
  var msg = document.getElementById('msg');
  var value;
  if(flag == 1) {
    value = msg.alpha + MSGSPEED;
  } else {
    value = msg.alpha - MSGSPEED;
  }
  msg.alpha = value;
  msg.style.opacity = (value / 100);
  msg.style.filter = 'alpha(opacity=' + value + ')';
  if(value >= 99) {
    clearInterval(msg.timer);
    msg.timer = null;
  } else if(value <= 1) {
    msg.style.display = "none";
    clearInterval(msg.timer);
  }
}

// calculate the position of the element in relation to the left of the browser //
function leftPosition(target) {
  var left = 0;
  if(target.offsetParent) {
    while(1) {
      left += target.offsetLeft;
      if(!target.offsetParent) {
        break;
      }
      target = target.offsetParent;
    }
  } else if(target.x) {
    left += target.x;
  }
  return left;
}

// calculate the position of the element in relation to the top of the browser window //
function topPosition(target) {
  var top = 0;
  if(target.offsetParent) {
    while(1) {
      top += target.offsetTop;
      if(!target.offsetParent) {
        break;
      }
      target = target.offsetParent;
    }
  } else if(target.y) {
    top += target.y;
  }
  return top;
}

// preload the arrow //
if(document.images) {
  arrow = new Image(7,80); 
  arrow.src = "/messages.gif"; 
}