// --------------------------------------------------------
// scripts relating to the autosuggest text box
// --------------------------------------------------------
/**
* An autosuggest textbox control.
* @class
* @scope public
*/
function AutoSuggestControl(oTextbox /*:HTMLInputElement*/,
                                oProvider /*:SuggestionProvider*/,
                                oSelectFunction,
                                oLookupFunction,
                                oSearchType) {

    /**
    * The currently selected suggestions.
    * @scope private
    */
    this.cur /*:int*/ = -1;

    /**
    * The dropdown list layer.
    * @scope private
    */
    this.layer = null;

    /**
    * Suggestion provider for the autosuggest feature.
    * @scope private.
    */
    this.provider /*:SuggestionProvider*/ = oProvider;

    /**
    * The textbox to capture.
    * @scope private
    */
    this.textbox /*:HTMLInputElement*/ = oTextbox;

    this.itemValue = "";
    this.searchType = oSearchType;

    // assign select function
    this.selectFunction = oSelectFunction;

    //initialize the control
    this.init();

    this.lookupFunction = oLookupFunction;
}

/**
* Autosuggests one or more suggestions for what the user has typed.
* If no suggestions are passed in, then no autosuggest occurs.
* @scope private
* @param aSuggestions An array of suggestion strings.
* @param bTypeAhead If the control should provide a type ahead suggestion.
*/
AutoSuggestControl.prototype.autosuggest = function(aSuggestions /*:Array*/,
                                                         bTypeAhead /*:boolean*/) {

    //make sure there's at least one suggestion
    if (aSuggestions.length > 0) {
        if (bTypeAhead) {
            this.typeAhead(aSuggestions[0]);
        }

        this.showSuggestions(aSuggestions);
    } else {
        this.hideSuggestions();
    }
};

/**
* Creates the dropdown layer to display multiple suggestions.
* @scope private
*/
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.textAlign = "left";
    this.layer.style.width = this.textbox.style.width;

    //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") {
                var textValue = (oTarget.attributes["htmlControlValue"] == null) ? "" : oTarget.attributes["htmlControlValue"].value;
                oThis.textbox.value = textValue;
                this.itemValue = (oTarget.attributes["itemValue"] == null) ? "" : oTarget.attributes["itemValue"].value;

                oThis.hideSuggestions();
                oThis.selectFunction(this);     // perform the search
            } else if (oEvent.type == "mouseover") {
                oThis.highlightSuggestion(oTarget);
            } else {
                oThis.textbox.focus();
            }
        };


    document.body.appendChild(this.layer);
};

//    /**
//     * Gets the left coordinate of the textbox.
//     * @scope private
//     * @return The left coordinate of the textbox in pixels.
//     */
//    AutoSuggestControl.prototype.getLeft = function () /*:int*/ {
//
//        var oNode = this.textbox;
//        var iLeft = 0;
//        
//        while(oNode.tagName != "BODY") {
//            iLeft += oNode.offsetLeft;
//            oNode = oNode.offsetParent;        
//        }
//        
//        return iLeft;
//    };

AutoSuggestControl.prototype.getLeft = function() {
    var obj = this.textbox;
    var curleft = 0;
    if (obj.offsetParent) {
        curleft = obj.offsetLeft
        while (obj = obj.offsetParent) {
            curleft += obj.offsetLeft
        }
    }
    return curleft;
}

//    /**
//     * Gets the top coordinate of the textbox.
//     * @scope private
//     * @return The top coordinate of the textbox in pixels.
//     */
//    AutoSuggestControl.prototype.getTop = function () /*:int*/ {
//
//        var oNode = this.textbox;
//        var iTop = 0;
//        
//        while(oNode.tagName != "BODY") {
//            iTop += oNode.offsetTop;
//            oNode = oNode.offsetParent;
//        }
//        
//        return iTop;
//    };show


AutoSuggestControl.prototype.getTop = function() {
    var obj = this.textbox
    var curtop = 0;
    if (obj.offsetParent) {
        curtop = obj.offsetTop
        while (obj = obj.offsetParent) {
            curtop += obj.offsetTop
        }
    }
    return curtop;
}

/**
* Handles three keydown events.
* @scope private
* @param oEvent The event object for the keydown event.
*/
AutoSuggestControl.prototype.handleKeyDown = function(oEvent /*:Event*/, context) {

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

        default:

            var r = this.lookupFunction(this);
            if (r == false) {
                if (this.isDropDownVisible() == true) {
                    this.hideSuggestions();
                    this.selectFunction(this);
                }
            }
            break;
    }

};

/**
* Handles keyup events.
* @scope private
* @param oEvent The event object for the keyup event.
*/
AutoSuggestControl.prototype.handleKeyUp = function(oEvent /*:Event*/) {

    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);
    }
};

/**
* Hides the suggestion dropdown.
* @scope private
*/
AutoSuggestControl.prototype.hideSuggestions = function() {
    this.layer.style.visibility = "hidden";
};


AutoSuggestControl.prototype.isDropDownVisible = function() {
    return (this.layer.style.visibility != "hidden");
};


/**
* Highlights the given node in the suggestions dropdown.
* @scope private
* @param oSuggestionNode The node representing a suggestion in the dropdown.
*/
AutoSuggestControl.prototype.highlightSuggestion = function(oSuggestionNode) {

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

/**
* Initializes the textbox with event handlers for
* auto suggest functionality.
* @scope private
*/
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) {
    this.textbox.onkeyup = 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, this);
    };

    //assign onblur event handler (hides suggestions)    
    this.textbox.onblur = function() {
        oThis.hideSuggestions();
    };

    //create the suggestions dropdown
    this.createDropDown();
};

/**
* Highlights the next suggestion in the dropdown and
* places the suggestion into the textbox.
* @scope private
*/
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);
        var textValue = (oNode.attributes["htmlControlValue"] == null) ? "" : oNode.attributes["htmlControlValue"].value;
        this.textbox.value = textValue;
        this.itemValue = (oNode.attributes["itemValue"] == null) ? "" : oNode.attributes["itemValue"].value;
    }
};

/**
* Highlights the previous suggestion in the dropdown and
* places the suggestion into the textbox.
* @scope private
*/
AutoSuggestControl.prototype.previousSuggestion = function() {
    var cSuggestionNodes = this.layer.childNodes;

    if (cSuggestionNodes.length > 0 && this.cur > 0) {
        var oNode = cSuggestionNodes[--this.cur];
        this.highlightSuggestion(oNode);
        var textValue = (oNode.attributes["htmlControlValue"] == null) ? "" : oNode.attributes["htmlControlValue"].value;
        this.textbox.value = textValue;
        this.itemValue = (oNode.attributes["itemValue"] == null) ? "" : oNode.attributes["itemValue"].value;
    }
};

/**
* Selects a range of text in the textbox.
* @scope public
* @param iStart The start index (base 0) of the selection.
* @param iLength The number of characters to select.
*/
AutoSuggestControl.prototype.selectRange = function(iStart /*:int*/, iLength /*:int*/) {

    //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();
};

/**
* Builds the suggestion layer contents, moves it into position,
* and displays the layer.
* @scope private
* @param aSuggestions An array of suggestions for the control.
*/
AutoSuggestControl.prototype.showSuggestions = function(aSuggestions /*:Array*/) {

    var oDiv = null;
    this.layer.innerHTML = "";  //clear contents of the layer

    for (var iCount = 0; iCount < aSuggestions.length; iCount++) {
        oDiv = document.createElement("div");
        oDiv.appendChild(document.createTextNode(this.GetDisplayValue(aSuggestions[iCount])));
        var oAttr = document.createAttribute("itemValue");
        oAttr.value = this.GetValue(aSuggestions[iCount]);
        oDiv.attributes.setNamedItem(oAttr);
        var oAttrDisplayValue = document.createAttribute("htmlControlValue");
        oAttrDisplayValue.value = this.GetText(aSuggestions[iCount]);
        oDiv.attributes.setNamedItem(oAttrDisplayValue);
        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.GetText = function(val) {
    var start = val.indexOf('{');
    var finish = val.indexOf('}');

    if (start == -1 || finish == -1)
        return val;

    var part = val.slice(0, start - 1);
    return part;
}

AutoSuggestControl.prototype.GetValue = function(val) {
    var start = val.indexOf('{');
    var finish = val.indexOf('}');

    if (start == -1 || finish == -1)
        return "";

    var part = val.slice(start + 1, finish);
    return part;
}

AutoSuggestControl.prototype.GetDisplayValue = function(val) {
    if (this.searchType == "suburbPostcode") {
        var start = val.indexOf('{');
        var finish = val.indexOf('}');

        if (start == -1 || finish == -1)
            return "";

        var part = val.slice(0, start - 1);
        return part;
    }
    if (this.searchType == "streetName") {
        var start = val.indexOf('{');
        var finish = val.indexOf('}');

        if (start == -1 || finish == -1)
            return "";

        var part = val.replace('{', '');
        var part = part.replace('}', '');
        return part;
    }
    return "";
}

/**
* Inserts a suggestion into the textbox, highlighting the 
* suggested part of the text.
* @scope private
* @param sSuggestion The suggestion for the textbox.
*/
AutoSuggestControl.prototype.typeAhead = function(sSuggestion /*:String*/) {

    //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);
    }
};