function AutoSuggestControl(oTextbox, oProvider) {

this.cur = -1;
this.layer = null;
this.provider = oProvider;
this.textbox = oTextbox;
this.init();

} AutoSuggestControl.prototype.init = function() {

var oThis = this;
this.textbox.setAttribute("autocomplete", "off");
this.textbox.onkeyup = function(oEvent) {
  if (!oEvent) {
    oEvent = window.event;
  }
  oThis.handleKeyUp(oEvent);
};
this.textbox.onkeydown = function (oEvent) {
  if (!oEvent) {
    oEvent = window.event;
  }
  oThis.handleKeyDown(oEvent);
};
this.textbox.onblur = function () {
  oThis.hideSuggestions();
};

this.createDropDown();

}; AutoSuggestControl.prototype.selectRange = function(iStart, iLength) {

if (this.textbox.createTextRange) {
  var oRange = this.textbox.createTextRange();
  oRange.moveStart("character", iStart);
  oRange.moveEnd("character", iLength - this.textbox.value.length);
  oRange.select();
} else if (this.textbox.setSelectionRange) {
  this.textbox.setSelectionRange(iStart, iLength);
}
this.textbox.focus();

}; AutoSuggestControl.prototype.typeAhead = function(sSuggestion) {

if (this.textbox.createTextRange || this.textbox.setSelectionRange) {
  var iLen = this.textbox.value.length;
  this.textbox.value = sSuggestion;
  this.selectRange(iLen, sSuggestion.length);
}

}; AutoSuggestControl.prototype.autosuggest = function(aSuggestions, bTypeAhead) {

if (aSuggestions.length > 0) {
  if (bTypeAhead) {
    this.typeAhead(aSuggestions[0]);
  }
  this.showSuggestions(aSuggestions);
} else {
  this.hideSuggestions();
}

}; AutoSuggestControl.prototype.handleKeyUp = function(oEvent) {

var iKeyCode = oEvent.keyCode;

if (iKeyCode == 8 || iKeyCode == 46) {
  this.provider.requestSuggestions(this, false);

} else if (iKeyCode < 32 || (iKeyCode >= 33 && iKeyCode <= 46) || (iKeyCode >= 112 && iKeyCode <= 123)) {
  //ignore
} else {
  this.provider.requestSuggestions(this, true);
}

}; AutoSuggestControl.prototype.handleKeyDown = function (oEvent) {

switch(oEvent.keyCode) {
  case 38: //up arrow
    this.previousSuggestion();
    break;
  case 40: //down arrow
    this.nextSuggestion();
    break;
  case 13: //enter
    this.hideSuggestions();
    break;
}

}; AutoSuggestControl.prototype.hideSuggestions = function() {

this.layer.style.visibility = "hidden";

}; AutoSuggestControl.prototype.highlightSuggestion = function(oSuggestionNode) {

for (var i=0; i < this.layer.childNodes.length; i++) {
  var oNode = this.layer.childNodes[i];
  if (oNode == oSuggestionNode) {
    oNode.className = "current"
  } else if (oNode.className == "current") {
    oNode.className = "";
  }
}

}; AutoSuggestControl.prototype.createDropDown = function() {

this.layer = document.createElement("div");
this.layer.className = "suggestions";
this.layer.style.visibility = "hidden";
this.layer.style.width = this.textbox.offsetWidth;
document.body.appendChild(this.layer);

var oThis = this;

this.layer.onmousedown = this.layer.onmouseup =
  this.layer.onmouseover = function(oEvent) {
    oEvent = oEvent || window.event;
    oTarget = oEvent.target || oEvent.srcElement;

    if (oEvent.type == "mousedown") {
      oThis.textbox.value = oTarget.firstChild.nodeValue;
      oThis.hideSuggestions();
    } else if (oEvent.type == "mouseover") {
      oThis.highlightSuggestion(oTarget);
    } else {
      oThis.textbox.focus();
    }
  };

}; AutoSuggestControl.prototype.getLeft = function() {

var oNode = this.textbox;
var iLeft = 0;

while (oNode.tagName != "BODY") {
  iLeft += oNode.offsetLeft;
  oNode = oNode.offsetParent;
}

return iLeft;

}; AutoSuggestControl.prototype.getTop = function() {

var oNode = this.textbox;
var iTop = 0;

while (oNode.tagName != "BODY") {
  iTop += oNode.offsetTop;
  oNode = oNode.offsetParent;
}

return iTop;

}; AutoSuggestControl.prototype.showSuggestions = function(aSuggestions) {

var oDiv = null;
this.layer.innerHTML = "";

for (var i = 0; i < aSuggestions.length; i++) {
  oDiv = document.createElement("div");
  oDiv.appendChild(document.createTextNode(aSuggestions[i]));
  this.layer.appendChild(oDiv);
}

this.layer.style.left = this.getLeft() + "px";
this.layer.style.top = (this.getTop()+this.textbox.offsetHeight) + "px";
this.layer.style.width = this.textbox.offsetWidth + "px";
this.layer.style.visibility = "visible";

}; AutoSuggestControl.prototype.nextSuggestion = function() {

var cSuggestionNodes = this.layer.childNodes;

if (cSuggestionNodes.length > 0 && this.cur < cSuggestionNodes.length-1) {
  var oNode = cSuggestionNodes[++this.cur];
  this.highlightSuggestion(oNode);
  this.textbox.value = oNode.firstChild.nodeValue;
}

}; AutoSuggestControl.prototype.previousSuggestion = function() {

var cSuggestionNodes = this.layer.childNodes;

if (cSuggestionNodes.length > 0 && this.cur > 0) {
  var oNode = cSuggestionNodes[--this.cur];
  this.highlightSuggestion(oNode);
  this.textbox.value = oNode.firstChild.nodeValue;
}

};

function bsearch(aArray, item, less_than) {

var left = -1,
    right = aArray.length,
    mid;
while (right > left + 1) {
  mid = (left + right) >>> 1;
  if (less_than(aArray[mid], item)) {
    left = mid;
  } else {
    right = mid;
  }
}
return right;

}