// Used for dynamically updating the height of a textarea

function resizeTextArea(id, rows) {

  var textarea = document.getElementById(id);

  if (!textarea || (typeof(textarea.rows) == "undefined")) return;

  textarea.rows = rows;

}

// A better way than for example hardcoding foo.onload

function addEvent(element, type, func){

  if (element.addEventListener) {

    element.addEventListener(type, func, false);

    return true;

  } else if (element.attachEvent) {

    return element.attachEvent("on" + type, func);

  }

  return false;

}

// Convenience function for the nearest ancestor element with a specific tag

// name

function getAncestorByTagName(e, tagName) {

  tagName = tagName.toLowerCase();

  do {

    e = e.parentNode;

  } while ((e.nodeType == 1) && (e.tagName.toLowerCase() != tagName));

  return (e.nodeType == 1) ? e : null;

}

// Adapted from http://www.kryogenix.org/code/browser/searchhi/

function searchHighlight() {

  if (!document.createElement) return;

  var div = document.getElementById("searchable");

  if (!div) return;

  function getSearchWords(url) {

    if (url.indexOf('?') == -1) return [];

    var queryString = url.substr(url.indexOf('?') + 1);

    var params = queryString.split('&';;

    for (var p in params) {

      var param = params[p].split('=');

      if (param.length < 2) continue;

      if (param[0] == 'q' || param[0] == 'p') { // q= for Google, p= for Yahoo

        var query = decodeURIComponent(param[1].replace(/\+/g, ' '));

        if (query[0] == '!') query = query.slice(1);

        words = query.split(/(".*?")|('.*?')|(\s+)/);

        var words2 = new Array();

        for (var w in words) {

          words[w] = words[w].replace(/^\s+$/, '');

          if (words[w] != '') {

            words2.push(words[w].replace(/^['"]/, '').replace(/['"]$/, ''));

          }

        }

        return words2;

      }

    }

    return [];

  }

  function highlightWord(node, word, searchwordindex) {

    // If this node is a text node and contains the search word, highlight it by

    // surrounding it with a span element

    if (node.nodeType == 3) { // Node.TEXT_NODE

      var pos = node.nodeValue.toLowerCase().indexOf(word.toLowerCase());

      if (pos >= 0 && !/^searchword\d$/.test(node.parentNode.className)) {

        var span = document.createElement("span");

        span.className = "searchword" + (searchwordindex % 5);

        span.appendChild(document.createTextNode(

          node.nodeValue.substr(pos, word.length)));

        node.parentNode.insertBefore(span, node.parentNode.insertBefore(

          document.createTextNode(node.nodeValue.substr(pos + word.length)),

            node.nextSibling));

        node.nodeValue = node.nodeValue.substr(0, pos);

        return true;

      }

    } else if (!node.nodeName.match(/button|select|textarea/i)) {

      // Recurse into child nodes

      for (var i = 0; i < node.childNodes.length; i++) {

        if (highlightWord(node.childNodes[i], word, searchwordindex)) i++;

      }

    }

    return false;

  }

  var words = getSearchWords(document.URL);

  if (!words.length) words = getSearchWords(document.referrer);

  if (words.length) {

    for (var w in words) {

      if (words[w].length) highlightWord(div, words[w], w);

    }

  }

}

function enableControl(id, enabled) {

  if (typeof(enabled) == "undefined") enabled = true;

  var control = document.getElementById(id);

  if (!control) return;

  control.disabled = !enabled;

  var label = getAncestorByTagName(control, "label");

  if (label) {

    label.className = enabled ? "enabled" : "disabled";

  } else {

    var labels = document.getElementsByTagName("label");

    for (var i = 0; i < labels.length; i++) {

      if (labels[i].htmlFor == id) {

        labels[i].className = enabled ? "enabled" : "disabled";

        break;

      }

    }

  }

}

function addHeadingLinks(container, title) {

  var base = document.location.pathname;

  function addLinks(elems) {

    for (var i = 0; i < elems.length; i++) {

      var hn = elems[i];

      if (hn.id) {

        var link = document.createElement('a');

        link.href = base + '#' + hn.id;

        link.className = 'anchor';

        link.title = title.replace(/\$id/, hn.id);

        link.appendChild(document.createTextNode(" \u00B6"));

        hn.appendChild(link);

      }

    }

  }

  for (var lvl = 0; lvl <= 6; lvl++) {

    addLinks(container.getElementsByTagName('h' + lvl));

  }

}