var _tabindex=1;

function AutoSuggestControl(oTextbox,oProvider,invincible) {
	this.cur = -1;
    this.layer = null;
    this.provider = oProvider;
    this.textbox = oTextbox;
    this.tabindex=_tabindex++;
    this.invincible=invincible;
    this.init(); 
}

AutoSuggestControl.prototype.autosuggest = function (aSuggestions,bTypeAhead) {
    
    //make sure there's at least one suggestion
    if (aSuggestions.length > 0) {
        if (bTypeAhead) {
           this.typeAhead(aSuggestions[0]);
        }
        
        this.showSuggestions(aSuggestions);
    } else {
        this.hideSuggestions();
    }
};

AutoSuggestControl.prototype.createDropDown = function () {

    var oThis = this;

    //create the layer and assign styles
    this.layer = document.createElement("div");
    this.layer.className = "suggestions";
    this.layer.style.visibility = "hidden";
    this.layer.style.width = this.textbox.offsetWidth;
    
    //when the user clicks on the a suggestion, get the text (innerHTML)
    //and place it into a textbox
    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();
        }
    };
    
    var sugw = document.getElementById('sugw');
    sugw.appendChild(this.layer);
};

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.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;
        case  9: //tab
        	if(this.textbox.value) this.nextSuggestionInput(oEvent.keyCode==13);
            break;
        case  8: //delete
        	if(this.textbox.value==""){
				this.deleteSelf();
				cancelEvent(oEvent);
			}
            else this.topSuggestion();
            break;
    }

};

AutoSuggestControl.prototype.handleKeyUp = function (oEvent) {

    var iKeyCode = oEvent.keyCode;

    //for backspace (8) and delete (46), shows suggestions without typeahead
    if (iKeyCode == 8 || iKeyCode == 46) {
        this.provider.requestSuggestions(this, false);
        
    //make sure not to interfere with non-character keys
    } else if (iKeyCode < 32 || (iKeyCode >= 33 && iKeyCode < 46) || (iKeyCode >= 112 && iKeyCode <= 123)) {
        //ignore
    } else {
        //request suggestions from the suggestion provider with typeahead
        this.provider.requestSuggestions(this, true);
    }
};

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.init = function () {

    //save a reference to this object
    var oThis = this;
    
    //assign the onkeyup event handler
    this.textbox.onkeyup = function (oEvent) {
    
        //check for the proper location of the event object
        if (!oEvent) {
            oEvent = window.event;
        }    
        
        //call the handleKeyUp() method with the event object
        oThis.handleKeyUp(oEvent);
    };
    
    //assign onkeydown event handler
    this.textbox.onkeydown = function (oEvent) {
    
        //check for the proper location of the event object
        if (!oEvent) {
            oEvent = window.event;
        }    
        
        //call the handleKeyDown() method with the event object
        oThis.handleKeyDown(oEvent);
    };
    
    //assign onblur event handler (hides suggestions)    
    this.textbox.onblur = function () {
        oThis.hideSuggestions();
    };
    
    //create the suggestions dropdown
    this.createDropDown();
};

AutoSuggestControl.prototype.nextSuggestion = function () {
    var cSuggestionNodes = this.layer.childNodes;
    //alert('next:'+cSuggestionNodes.length + ':'+ this.cur)

    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.topSuggestion = function () {
    this.cur = -1;
};

AutoSuggestControl.prototype.previousSuggestion = function () {
    var cSuggestionNodes = this.layer.childNodes;
	//alert('prev:'+cSuggestionNodes.length + ':'+ this.cur)

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

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

    //use text ranges for Internet Explorer
    if (this.textbox.createTextRange) {
        var oRange = this.textbox.createTextRange(); 
        oRange.moveStart("character", iStart); 
        oRange.moveEnd("character", iLength - this.textbox.value.length);      
        oRange.select();
        
    //use setSelectionRange() for Mozilla
    } else if (this.textbox.setSelectionRange) {
        this.textbox.setSelectionRange(iStart, iLength);
    }     

    //set focus back to the textbox
    this.textbox.focus();      
}; 

AutoSuggestControl.prototype.showSuggestions = function (aSuggestions) {
    
    var oDiv = null;
    this.layer.innerHTML = "";  //clear contents of the layer
    
    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.visibility = "visible";

};

AutoSuggestControl.prototype.typeAhead = function (sSuggestion) {

    //check for support of typeahead functionality
    if (this.textbox.createTextRange || this.textbox.setSelectionRange){
        var iLen = this.textbox.value.length; 
        this.textbox.value = sSuggestion; 
        this.selectRange(iLen, sSuggestion.length);
    }
};

//var catCount=1;
AutoSuggestControl.prototype.nextSuggestionInput = function (focus) {
	var num = parseInt(this.textbox.id.substr(3));
	//alert(this.textbox.id+'->'+num+' / '+(focus?'FOCUS':''));
	num++;
	var next = document.getElementById('cat'+num);
	if(next){
		//if(focus) next.focus();
	}else{
		addSuggestionInput(focus,num);
	}
};

AutoSuggestControl.prototype.deleteSelf = function () {
	if(this.invincible) return;
	var d = document.getElementById('catList');
	var c = this.textbox.parentNode.previousSibling.childNodes;
	c[c.length-1].focus();
	d.removeChild(this.textbox.parentNode);
	this.textbox='';
};

function addSuggestionInput(focus,num){
	var d = document.getElementById('catList');
	var s = document.createElement("span");
	var l = document.createElement("label");
	var i = document.createElement("input");
	s.id='s'+num;
	l.innerHTML=' -> ';
	i.name=i.id='cat'+num;
	s.appendChild(l);
	s.appendChild(i);
	d.appendChild(s);
	new AutoSuggestControl(document.getElementById('cat'+num), new GetSuggestions());
	if(focus) i.focus();
}

function cancelEvent(e) {
    e = e||event;
	if(e.preventDefault) {
		e.preventDefault();
	}else if(e.stopPropagation){
        e.stopPropagation();
    }
	e.returnValue = false;
    e.cancelBubble = true
}
/**/