/* Essential javascripts, used a lot. 
 * These should be placed inline
 * We have to be certain they are loaded before anything that uses them 
 */

// check for ie5 mac
var bugRiddenCrashPronePieceOfJunk = (
    navigator.userAgent.indexOf('MSIE 5') != -1
    &&
    navigator.userAgent.indexOf('Mac') != -1
)

// check for W3CDOM compatibility
var W3CDOM = (!bugRiddenCrashPronePieceOfJunk &&
               typeof document.getElementsByTagName != 'undefined' &&
               typeof document.createElement != 'undefined' );

// cross browser function for registering event handlers
var registerEventListener = null;

if (typeof addEvent != 'undefined') {
    // use Dean Edwards' function if available
    registerEventListener = function (elem, event, func) {
        addEvent(elem, event, func);
        return true;
    }
} else if (window.addEventListener) {
    registerEventListener = function (elem, event, func) {
        elem.addEventListener(event, func, false);
        return true;
    }
} else if (window.attachEvent) {
    registerEventListener = function (elem, event, func) {
        var result = elem.attachEvent("on"+event, func);
        return result;
    }
} else {
    registerEventListener = function (elem, event, func) {
        // maybe we could implement something with an array
        return false;
    }
}

// cross browser function for unregistering event handlers
var unRegisterEventListener = null;

if (typeof removeEvent != 'undefined') {
    // use Dean Edwards' function if available
    unRegisterEventListener = function (elem, event, func) {
        removeEvent(element, event, func);
        return true;
    }
} else if (window.removeEventListener) {
    unRegisterEventListener = function (elem, event, func) {
        elem.removeEventListener(event, func, false);
        return true;
    }
} else if (window.detachEvent) {
    unRegisterEventListener = function (elem, event, func) {
        var result = elem.detachEvent("on"+event, func);
        return result;
    }
} else {
    unRegisterEventListener = function (elem, event, func) {
        // maybe we could implement something with an array
        return false;
    }
}

var registerPloneFunction = null;

if (typeof addDOMLoadEvent != 'undefined') {
    registerPloneFunction = function (func) {
        // registers a function to fire ondomload.
        addDOMLoadEvent(func);
    }
} else {
    registerPloneFunction = function (func) {
        // registers a function to fire onload.
        registerEventListener(window, "load", func);
    }
}

function getContentArea() {
    // returns our content area element
    if (W3CDOM) {
        var node = document.getElementById('region-content');
        if (!node) {
            node = document.getElementById('content');
        }
        return node;
    }
} 

// Functions used by login pages

function cookiesEnabled() {
  // Test whether cookies are enabled by attempting to set a cookie and then change its value
  // set test cookie
  var c = "areYourCookiesEnabled=0";
  document.cookie = c;
  var dc = document.cookie;
  // cookie not set?  fail
  if (dc.indexOf(c) == -1) return 0;
  // change test cookie
  c = "areYourCookiesEnabled=1";
  document.cookie = c;
  dc = document.cookie;
  // cookie not changed?  fail
  if (dc.indexOf(c) == -1) return 0;
  // delete cookie
  document.cookie = "areYourCookiesEnabled=; expires=Thu, 01-Jan-70 00:00:01 GMT";
  return 1;
}

function setLoginVars(user_name_id, alt_user_name_id, password_id, empty_password_id, js_enabled_id, cookies_enabled_id) {
  // Indicate that javascript is enabled, set cookie status, copy username and password length info to 
  // alternative variables since these vars are removed from the request by zope's authentication mechanism.
  if (js_enabled_id) {
    el = document.getElementById(js_enabled_id);
    if (el) { el.value = 1; }
  }
  if (cookies_enabled_id) {
    el = document.getElementById(cookies_enabled_id);
    // Do a fresh cookies enabled test every time we press the login button
    //   so that we are up to date in case the user enables cookies after seeing
    //   the cookies message.
    if (el) { el.value = cookiesEnabled(); } 
  }
  if (user_name_id && alt_user_name_id) {
    user_name = document.getElementById(user_name_id)
    alt_user_name = document.getElementById(alt_user_name_id)
    if (user_name && alt_user_name) {
       var userName = user_name.value;
       var ix = userName.indexOf( '@' );
       if ( ix != -1 ) { userName = userName.substring( 0, ix ); }
       alt_user_name.value = userName;
       user_name.value = userName;
    } 
  }
  if (password_id && empty_password_id) {
    password = document.getElementById(password_id)
    empty_password = document.getElementById(empty_password_id)
    if (password && empty_password) {
       if (password.value.length==0) {
          empty_password.value = '1';
       } else {
          empty_password.value = '0';
       }
    }
  }
  return 1;
}

function showCookieMessage(msg_id) {
  // Show the element with the given id if cookies are not enabled
  msg = document.getElementById(msg_id)
  if (msg) {
     if (cookiesEnabled()) {
        msg.style.display = 'none';
     } else {
        msg.style.display = 'block';
     }
  }
}

function showEnableCookiesMessage() {
  // Show the element with the id 'enable_cookies_message' if cookies are not enabled
  showCookieMessage('enable_cookies_message')
}
// Call showEnableCookiesMessage after the page loads
registerPloneFunction(showEnableCookiesMessage);