/* (c) 2001 Ulrich Kritzner */

function Wave_Step()
{
  if (this.timestep==0)
    this.TimerFunc();
}

function Wave_TimerFunc()
{
  var i;
  with (this)
  {
    for (i=piccount-1;i>0;i--)
      current[i]=current[i-1];
    switch (direction)
    {
      case 0:
        position=(position+1)%count;
	break;
      case 1:
        position=(position+count-1)%count;
	break;
      case 2:
        if (position<count-1)
          position++;
	else
	  direction=3;
	break;
      case 3:
        if (position>0)
          position--;
	else
	  direction=2;
	break;
      case 4:
        if (position<count-1)
          position++;
	else if (current[piccount-1]==count-1)
	  Stop();
	break;
      case 5:
        if (position>0)
          position--;
	else if (current[piccount-1]==0)
	  Stop();
	break;
    }
    current[0]=position*step;
    for (i=piccount-1;i>=0;i--)
      window.document.images[start+current[i]].src=pic[i].src;
  }
}

function Wave_Stop()
{
  var oldrun=this.timestep;
  this.timestep=0;
  if ((this.EventHandler)&&(oldrun>0))
    this.EventHandler(0);
}

function Wave_Run(direction)
{
  this.Stop();
  this.direction=direction;
  if (this.EventHandler)
    this.EventHandler(1);
  this.timestep=this.time_step;
  u_timer_continue();
}

function Wave_Time_Step(time_step)
{
  this.Stop();
  this.time_step=time_step;
  if (this.EventHandler)
    this.EventHandler(1);
  this.timestep=this.time_step;
  u_timer_continue();
}

function Wave_Clear()
{
  var i;
  with (this)
  {
    for (i=0;i<piccount;i++)
      window.document.images[start+current[i]].src=pic[piccount-1].src;
  }
}

function Wave_Right()
{
  if (this.timestep>0)
    this.Clear();
  with (this)
  {
    position=count-1;
    Align();
  }
}

function Wave_Left()
{
  if (this.timestep>0)
    this.Clear();
  with (this)
  {
    position=0;
    Align();
  }
}

function Wave_Align()
{
  var i;
  for (i=0;i<this.piccount;i++)
    this.current[i]=this.position*this.step;
}

function Wave_Set_Event_Handler(eventhandler)
{
  this.EventHandler=eventhandler;
}

function Wave_Add_Picture(picture)
{
  with (this)
  {
    pic[piccount]=picture;
    current[piccount]=current[0];
    piccount++;
  }
}

function Wave(start,count,step,time_step)
{
  this.current=new Array();
  this.pic=new Array();
  this.piccount=0;
  this.start=start;
  this.count=count;
  this.time_step=time_step;
  this.direction=1;
  this.position=0;
  this.step=step;
  this.Step=Wave_Step;
  this.TimerFunc=Wave_TimerFunc;
  this.Stop=Wave_Stop;
  this.Run=Wave_Run;
  this.Right=Wave_Right;
  this.Left=Wave_Left;
  this.TimeStep=Wave_Time_Step;
  this.Clear=Wave_Clear;
  this.SetEventHandler=Wave_Set_Event_Handler;
  this.AddPicture=Wave_Add_Picture;
  this.Align=Wave_Align;
  this.timestep=0;
  this.timeval=0;
  u_timer_add_object(this);
}