// PicShow, Copyright 2004, Spanto Soft sl. www.spanto.com, info@spanto.com
var PS_totalImages=0;
var PS_loopingmode;
var PS_usealpha;
var PS_alpha;
var PS_lastImageSelected;
var PS_lastImageIndexSelected;
var PS_alpha_step;
var PS_index;
var PS_aheadOn=0;
var PS_backOn=0;
var PS_scroll_speed_min=500;
var PS_scroll_speed_max=100;
var PS_scroll_speed_step=5;
var PS_scroll_speed_actual=500;
var PS_img_lit = new Array();
var PS_img_big = new Array();
var PS_button_ahead=new Array();
var PS_button_back=new Array();

function PicShow_Init(totalimages,numOnScreen,loopingmode,usealpha,alphastep,scrollspeedmin,scrollspeedmax,scrollspeedstep)
		{
		PS_alpha=0;
		PS_index=0;
		PS_totalImages=totalimages;
		PS_imagesOnScreen=numOnScreen;
		PS_loopingmode=loopingmode;
		PS_usealpha=usealpha;
		PS_alpha_step=alphastep;
		PS_scroll_speed_min=scrollspeedmin;
		PS_scroll_speed_max=scrollspeedmax;
		PS_scroll_speed_step=scrollspeedstep;
		PS_scroll_speed_actual=scrollspeedmin;
		}
		
function PicShow_InitImg(numimg,name_lit,name_big)
		 {
		 PS_img_lit[numimg] = new Image();
		 PS_img_lit[numimg].src = name_lit;
		 PS_img_big[numimg] = new Image();
		 PS_img_big[numimg].src = name_big;
		 }
													 
function PicShow_InitButtonBack(button_off,button_on)
		{
		 PS_button_back[0] = new Image();
		 PS_button_back[0].src = button_off;
		 PS_button_back[1] = new Image();
		 PS_button_back[1].src = button_on;
		 
		 document.PicShowButtonBack.src= PS_button_back[0].src;
		}

function PicShow_InitButtonAhead(button_off,button_on)
		{
		 PS_button_ahead[0] = new Image();
		 PS_button_ahead[0].src = button_off;
		 PS_button_ahead[1] = new Image();
		 PS_button_ahead[1].src = button_on;
		 
		 document.PicShowButtonAhead.src= PS_button_ahead[0].src;		 
		}
		 
function PicShow_Refresh()
		{
		var t;
		var ele;
		var rt;
		
		for (t=0; t<PS_imagesOnScreen; t++)
			{
			ele='PicShow'+t;
			rt=PS_index+t;
			if (rt>=PS_totalImages) { rt-=PS_totalImages; }
			
			document.getElementById(ele).src= PS_img_lit[rt].src;
			}
			
		
		}
		
function PicShow_GoAhead()
		{
		PS_aheadOn=1;
		document.PicShowButtonAhead.src= PS_button_ahead[1].src;
		PS_scroll_speed_actual=PS_scroll_speed_min;
		PicShow_Ahead();
		}
function PicShow_GoBack()
		{
		PS_backOn=1;
		document.PicShowButtonBack.src= PS_button_back[1].src;
		PS_scroll_speed_actual=PS_scroll_speed_min;						
		PicShow_Back();
		}
function PicShow_StopAhead()
		{
		PS_aheadOn=0;
		document.PicShowButtonAhead.src= PS_button_ahead[0].src;
		}
function PicShow_StopBack()
		{
		PS_backOn=0;
		document.PicShowButtonBack.src= PS_button_back[0].src;						
		}
		
		
function PicShow_Ahead()
		{
		var maxindex;
		
		if (PS_aheadOn!=1) return;
		
		PS_index++;
		
		switch(PS_loopingmode)
			  {
			  case 0: // no looping mode activated
			  	maxindex=(PS_totalImages-PS_imagesOnScreen);
				if (PS_index>=maxindex)
					{
					PS_index=maxindex;
					}
			    break;
			  case 1: // looping mode activated
 			    maxindex=PS_totalImages;
				if (PS_index>=maxindex)
					{
					PS_index-=maxindex;
					}
			    break;
			  }
		PicShow_Refresh();
		
		if (PS_aheadOn==1) { setTimeout('PicShow_Ahead()',PS_scroll_speed_actual); }					
		PS_scroll_speed_actual-=PS_scroll_speed_step;
		if (PS_scroll_speed_actual<PS_scroll_speed_max) { PS_scroll_speed_actual=PS_scroll_speed_max; }
		}
		
		
function PicShow_Back()
		{
		if (PS_backOn!=1) return;
		
		PS_index--;
		switch(PS_loopingmode)
			  {
			  case 0: // no looping mode activated
				if (PS_index<0) { PS_index=0; }
			    break;
			  case 1: // looping mode activated
			    if (PS_index<0) { PS_index=PS_totalImages+PS_index; }
			    break;
			  }
				
		PicShow_Refresh();		
		if (PS_backOn==1) { setTimeout('PicShow_Back()',PS_scroll_speed_actual); }							
		PS_scroll_speed_actual-=PS_scroll_speed_step;
		if (PS_scroll_speed_actual<PS_scroll_speed_max) { PS_scroll_speed_actual=PS_scroll_speed_max; }

		}


function PicShow_Select(numImgSelected)
		{
		PS_lastImageSelected=numImgSelected;
		PS_lastImageIndexSelected=PS_index;
		PicShow_Selected();
		}
		
function PicShow_Selected()
		{
		var ni;

		ni=PS_lastImageIndexSelected+PS_lastImageSelected;
		if (ni>=PS_totalImages) { ni-=PS_totalImages; }		
		

		if (document.PicShowBig.src!=PS_img_big[ni].src)
			{
			if (PS_usealpha==1)
				{
				if (PS_alpha>0) {
								PicShow_ChangeAlpha(PS_alpha-PS_alpha_step);					
								setTimeout('PicShow_Selected()',10)
								return;
								}	
							
				PS_alpha=0;
				}
			else{
				PS_alpha=100;
				}
			
			PicShow_ChangeAlpha(PS_alpha);					
			document.PicShowBig.src= PS_img_big[ni].src;
			if (PS_alpha<100) { setTimeout('PicShow_Selected()',10); }
			}
		else{
			if (PS_alpha<100) 
				{
				PicShow_ChangeAlpha(PS_alpha+PS_alpha_step);
				setTimeout('PicShow_Selected()',10)
				}
			}
		}
		
function PicShow_ChangeAlpha(nalpha)
		{
		PS_alpha=nalpha;
		if (PS_alpha<0) { PS_alpha=0; }
		if (PS_alpha>100) { PS_alpha=100; }
		
		
		if (navigator.appName == "Microsoft Internet Explorer")
			{
			document.PicShowBig.filters.alpha.opacity = PS_alpha ;
			}
		else{
			document.PicShowBig.style.MozOpacity = PS_alpha + "%";
			}			
		
		}