function AutoSuggestControl(oTextbox, oProvider) {
    this.provider = oProvider;
    this.textbox = oTextbox;

    this.init();
}

AutoSuggestControl.prototype.autosuggest = function (aSuggestions) {
    if (aSuggestions.length > 0) {
        this.typeAhead(aSuggestions[0]);
    }
};

AutoSuggestControl.prototype.handleKeyUp = function (oEvent) {

    var iKeyCode = oEvent.keyCode;

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

AutoSuggestControl.prototype.init = function () {
    var oThis = this;
    
    this.textbox.onkeyup = function (oEvent) {
    
        if (!oEvent) oEvent = window.event;
        oThis.handleKeyUp(oEvent);
    };
};

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);
    }
};