// javascript implementation of ArrayList

// Consider using ArrayPlus instead of ArrayList (it's an actual array so it will be serialized identically to a normal array; and it can be initialized with an array)

function ArrayList() { this.aList = []; }
		
ArrayList.prototype.Count = function() { return this.aList.length; }		

ArrayList.prototype.Add = function( object ) { return this.aList.push( object ); }

ArrayList.prototype.GetAt = function( index ) {
    if( index > -1 && index < this.aList.length )
	    return this.aList[index];
    else
    	return undefined;
}

ArrayList.prototype.Clear = function(){ this.aList = []; }

ArrayList.prototype.RemoveAt = function ( index ){
    var m_count = this.aList.length;
    if ( m_count > 0 && index > -1 && index < this.aList.length ) 
    {
	    switch( index )
	    {
		    case 0:
			    this.aList.shift();
			    break;
		    case m_count - 1:
			    this.aList.pop();
			    break;
		    default:
			    var head   = this.aList.slice( 0, index );
			    var tail   = this.aList.slice( index + 1 );
			    this.aList = head.concat( tail );
			    break;
	    }
    }
}

ArrayList.prototype.Insert = function (object,index){
    var m_count       = this.aList.length;
    var m_returnValue = -1;
    			
    if ( index > -1 && index <= m_count ) 
    {
	    switch(index)
	    {
		    case 0:
			    this.aList.unshift(object);
			    m_returnValue = 0;
			    break;
		    case m_count:
			    this.aList.push(object);
			    m_returnValue = m_count;
			    break;
		    default:
			    var head = this.aList.slice(0, index - 1);
			    var tail = this.aList.slice(index);
			    this.aList = this.aList.concat(tail.unshift(object));
			    m_returnValue = index;
			    break;
	    }
    }
    			
    return m_returnValue;
}

ArrayList.prototype.IndexOf = function(object, startIndex){
    var m_count       = this.aList.length;
    var m_returnValue = - 1;
    			
    if ( startIndex > -1 && startIndex < m_count ) 
    {
	    var i = startIndex;		
	    while( i < m_count )
	    {
		    if ( this.aList[i] == object )
		    {
			    m_returnValue = i;
			    break;
		    }			
		    i++;
	    }
    }
    			
    return m_returnValue;
}
		
		
ArrayList.prototype.LastIndexOf = function( object, startIndex ){
    var m_count       = this.aList.length;
    var m_returnValue = - 1;
    			
    if ( startIndex > -1 && startIndex < m_count ) 
    {
	    var i = m_count - 1;			
	    while( i >= startIndex )
	    {
		    if ( this.aList[i] == object )
		    {
			    m_returnValue = i;
			    break;
		    }
		    i--;
	    }
    }
    			
    return m_returnValue;
}


// Observer pattern implementation

function Observer(){ this.Update = function(){ return; } }

function Subject(){ this.observers = new ArrayList(); }

Subject.prototype.Notify = function( context ){
	var m_count = this.observers.Count();
			
	for( var i = 0; i < m_count; i++ )
		this.observers.GetAt(i).Update( context );
}

Subject.prototype.AddObserver = function( observer ){
    if( !observer.Update )
	    throw 'Bad argument';

    this.observers.Add( observer );
}

Subject.prototype.RemoveObserver = function( observer ){
    if( !observer.Update )
	    throw 'Bad argument';
       
    this.observers.RemoveAt(this.observers.IndexOf( observer, 0 ));
}
		
		
function inherits(base, extension)
{
	for (var property in base)
	{
		try
		{
			extension[property] = base[property];
		}
		catch(warning)
		{
		}
	}
}

////////////////////////////////////////////
// End of script
if (typeof(Sys) !== 'undefined')
{
    Sys.Application.notifyScriptLoaded();
}
////////////////////////////////////////////
// Do not add any code below this
////////////////////////////////////////////