var goExpanderManager = new cExpanderManager();



/*

 * class to manage top level expander state between page

 * loads

 */

function cExpanderManager()

{

    this.expanders = new Array();

    this.formElement = null;

    

    this.add = cExpanderManager_Add;

    this.initialize = cExpanderManager_Initialize;

    this.registerOpen = cExpanderManager_RegisterOpen;

    this.registerClose = cExpanderManager_RegisterClose;

    this.isVisible = function() { return true; }

    this.isElementVisible = cExpanderManager_IsElementVisible;

}



function cExpanderManager_Add( oExpander )

{

    this.expanders[this.expanders.length] = oExpander;

    oExpander.manager = this;

}



function cExpanderManager_Initialize()

{

    if (this.formElement == null)

        return;

        

    for(var i=0; i < this.expanders.length; i++)

    {

        this.expanders[i].initialize( this.isElementVisible( this.expanders[i].element.id ) );

    }

}



function cExpanderManager_RegisterOpen( oExpander )

{

    if (this.formElement == null)

        return;



    if (this.formElement.value.indexOf( oExpander.element.id ) < 0 )

    {

        if (this.formElement.value != '')

            this.formElement.value += ",";

        this.formElement.value += oExpander.element.id;

    }  

}



function cExpanderManager_RegisterClose( oExpander )

{

    if (this.formElement == null)

        return;



    var rx = new RegExp( oExpander.element.id, '' );

    var text = this.formElement.value;

    text = text.replace( rx, '' );

    text = text.replace( /,,/g, ',' );

    if (text.substr(0, 1) == ',')

        text = text.slice( 1 );

    if (text.substr(-1) == ',')

        text = text.slice( 0, -1);

    this.formElement.value = text;

}



function cExpanderManager_IsElementVisible( id )

{

    rx = new RegExp( id, '' );

    return rx.test( this.formElement.value );

}



/*

 * basic expander class to handle an expandable element

 * that expands or contracts child elements.

 */

function cExpander( elm )

{

    this.element = elm;

    this.element.expander = this;

    this.children = new Array();

    this.bIsOpen = false;

    this.manager = null; 

    

    this.addElement = cExpander_AddElement;

    this.open = cExpander_Open;

    this.close = cExpander_Close;

    this.expand = cExpander_Expand;

    this.contract = cExpander_Contract;

    this.toggle = cExpander_Toggle;

    this.initialize = cExpander_Initialize;

    this.registerOpen = cExpander_RegisterOpen;

    this.registerClose = cExpander_RegisterClose;

    this.isVisible = cExpander_IsVisible;

}



function cExpander_AddElement( elm )

{

    this.children[this.children.length] = elm;

    elm.manager = this;

}



function cExpander_Open()

{

    for( var i=0; i<this.children.length; i++)

    {

        this.children[i].element.style.display = 'block';

        if (this.children[i].bIsOpen)

        {

            this.children[i].open();

        }

    }

}



function cExpander_Close()

{

    for( var i=0; i<this.children.length; i++)

    {

        this.children[i].element.style.display = 'none';

        this.children[i].close();

    }

}



function cExpander_Expand()

{

    this.bIsOpen = true;

    this.registerOpen( this );

}



function cExpander_Contract()

{

    this.bIsOpen = false;

    this.registerClose( this );

}



function cExpander_Toggle()

{

    if (this.bIsOpen)

        this.contract();

    else

        this.expand();

}



/* intialize this and all children recursively */

function cExpander_Initialize( bState )

{

    this.bIsOpen = bState;

    for( var i=0; i<this.children.length; i++)

    {

        var child = this.children[i];

        if (this.isVisible())

            child.element.style.display = 'block';

        this.children[i].initialize( goExpanderManager.isElementVisible( child.element.id ));

    }

}



/* cascade registration to top level manager */

function cExpander_RegisterOpen(elm)

{

    if (this.manager != null)

        this.manager.registerOpen( elm );

    this.open();

}



function cExpander_RegisterClose(elm)

{

    if (this.manager != null)

        this.manager.registerClose( elm );

    this.close();

}



/* determine if all elements in heirarchy are also open */

function cExpander_IsVisible()

{

    var bVisible = this.bIsOpen;

    if (this.manager != null)

        bVisible = bVisible && this.manager.isVisible();

    return bVisible;

}