/*==================================================*
 $Id: slideshow.js,v 1.16 2003/10/14 12:39:00 pat Exp $
 Copyright 2000-2003 Patrick Fitzgerald
 http://slideshow.barelyfitz.com/

 This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License 
 as published by  the Free Software Foundation; either version 2 of the License, or (at your option) any later version.

 This program is distributed in the hope that it will be useful,  but WITHOUT ANY WARRANTY; without even the implied warranty of
 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the  GNU General Public License for more details.

 You should have received a copy of the GNU General Public License  along with this program; if not, write to the 
 Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

 There are two objects defined in this file: 
"slide" - contains all the information for a single slide
 "slideshow" - consists of multiple slide objects and runs the slideshow

 slide object
 This is the constructor function for the slide object.
 It is called automatically when you create a new slide object.
 For example:
 s = new slide();
*==================================================*/
 
function slide(src,link,text,target,attr,alt) 
{
		this.src = src;            //=> Image URL
		this.link = link;        //=> Link URL
		this.text = text;         //=> Text to display
		this.target = target;   //=> Name of the target window ("_blank")
		this.attr = attr;          //=> Custom duration for the slide, in milliseconds.
		this.alt = alt;             //=> ALT atribute.
		
		if (document.images) { this.image = new Image(); }
		this.loaded = false;		
		this.load = function() 
		{
				if (!document.images) { return; }
				if (!this.loaded) 
				{
						this.image.src = this.src;						
						this.image.alt = this.alt;						
						this.loaded = true;
				}
		}
		
		this.hotlink = function() 
		{
				var mywindow;
				if (!this.link) return;
				if (this.target) 
				{
						if (this.attr) { mywindow = window.open(this.link, this.target, this.attr); } else {mywindow = window.open(this.link, this.target); }
						if (mywindow && mywindow.focus) mywindow.focus();
				} 
				else { location.href = this.link; }
		}
		
}


function slideshow( slideshowname ) 
{
		this.name = slideshowname;
		this.repeat = true;
		this.prefetch = 2;
		this.image;
		this.textid;
		this.textarea;
		this.timeout = 3000;
		this.slides = new Array();
		this.current = 0;
		this.timeoutid = 0;
		
		this.add_slide = function(slide) 
		{
				var i = this.slides.length;
				if (this.prefetch == -1) {  slide.load();  }
				this.slides[i] = slide;
		}
		
		this.play = function(timeout) 
		{
				this.pause();
				if (timeout) {  this.timeout = timeout;  }
				if (typeof this.slides[ this.current ].timeout != 'undefined') { timeout = this.slides[ this.current ].timeout; } else {  timeout = this.timeout;  }
				this.timeoutid = setTimeout( this.name + ".loop()", timeout);								
				//=> Add on by LS to rotate arrows on the right menu
				var nn=1;	
				nn=this.current+1;
				for (i=1; i<7; i++)	
				{ 
						if (i==nn) {document.getElementById("arr" + nn).src="images/s_arrow1.gif";} 
						else {document.getElementById("arr" + i).src="images/s_arrow0.gif";}
				}
				//=> Add on by LS to rotate arrows on the right menu				
		}
						
		this.pause = function() 
		{
				if (this.timeoutid != 0) {
						clearTimeout(this.timeoutid);
						this.timeoutid = 0;
				}
		}
		
		this.update = function() 
		{
				if (! this.valid_image()) { return; }
				if (typeof this.pre_update_hook == 'function') { this.pre_update_hook(); }
				var slide = this.slides[ this.current ];
				var dofilter = false;
				if (this.image &&  typeof this.image.filters != 'undefined' && typeof this.image.filters[0] != 'undefined') {  dofilter = true;  }				
				slide.load();
				if (dofilter) 
				{
						if (slide.filter && this.image.style && this.image.style.filter) {  this.image.style.filter = slide.filter;  }
						this.image.filters[0].Apply();
				}			
				this.image.alt = slide.image.alt; //=> Add on by LS: to display image alt text
				this.image.src = slide.image.src;
				if (dofilter) {  this.image.filters[0].Play(); }
				this.display_text();
				if (typeof this.post_update_hook == 'function') {  this.post_update_hook();  }
				if (this.prefetch > 0) 	
				{
						var next, prev, count;
						next = this.current;
						prev = this.current;
						count = 0;
						do 
						{
								if (++next >= this.slides.length) next = 0;
								if (--prev < 0) prev = this.slides.length - 1;
								this.slides[next].load();
								this.slides[prev].load();
						} 
						while (++count < this.prefetch);
				}
		}
		
		this.goto_slide = function(n) 
		{
				if (n == -1) { n = this.slides.length - 1;   }
				if (n < this.slides.length && n >= 0) {  this.current = n;   }
				this.update();
		}
		
		this.goto_random_slide = function(include_current) 
		{
				var i;
				if (this.slides.length > 1) 
				{
						do { i = Math.floor(Math.random()*this.slides.length); } while (i == this.current);
						this.goto_slide(i);
				}
		}
		
		this.next = function() 
		{
				if (this.current < this.slides.length - 1) {this.current++;} else if (this.repeat) {this.current = 0;}
				this.update();
		}
		
		this.previous = function() 
		{
				if (this.current > 0) {  this.current--; } else if (this.repeat) { this.current = this.slides.length - 1; }
				this.update();
		}
		
		this.shuffle = function() 
		{
				var i, i2, slides_copy, slides_randomized;
				slides_copy = new Array();
				for (i = 0; i < this.slides.length; i++) {  slides_copy[i] = this.slides[i];  }
				slides_randomized = new Array();
				do 
				{
						i = Math.floor(Math.random()*slides_copy.length);
						slides_randomized[ slides_randomized.length ] =
						slides_copy[i];
						for (i2 = i + 1; i2 < slides_copy.length; i2++) { slides_copy[i2 - 1] = slides_copy[i2]; }
						slides_copy.length--;
				} 
				while (slides_copy.length);
				this.slides = slides_randomized;
		}
		
		this.get_text = function() { return(this.slides[ this.current ].text); }
		
		this.get_all_text = function(before_slide, after_slide) 
		{
				all_text = "";
				for (i=0; i < this.slides.length; i++) {
						slide = this.slides[i];
						if (slide.text) {all_text += before_slide + slide.text + after_slide;}
				}
				return(all_text);
		}
		
		this.display_text = function(text) 	
		{
				if (!text) { text = this.slides[ this.current ].text; }
				if (this.textarea && typeof this.textarea.value != 'undefined') { this.textarea.value = text; }
				if (this.textid) {
						r = this.getElementById(this.textid);
						if (!r) { return false; }
						if (typeof r.innerHTML == 'undefined') { return false; }
						r.innerHTML = text;
				}
		}
		
		this.hotlink = function() 
		{ 
				this.slides[ this.current ].hotlink();
		}
		
		this.save_position = function(cookiename)  
		{
				if (!cookiename) { cookiename = this.name + '_slideshow'; }
				document.cookie = cookiename + '=' + this.current;
		}
		
		this.restore_position = function(cookiename)  
		{
				if (!cookiename) { cookiename = this.name + '_slideshow'; }
				var search = cookiename + "=";
				if (document.cookie.length > 0) 
				{ 
						offset = document.cookie.indexOf(search);
						if (offset != -1) 
						{ 
								offset += search.length;
								end = document.cookie.indexOf(";", offset);
								if (end == -1) end = document.cookie.length;
								this.current = parseInt(unescape(document.cookie.substring(offset, end)));
						}
				}
		}
		
		this.noscript = function() 
		{
				$html = "\n";  
				for (i=0; i < this.slides.length; i++) 
				{  
						slide = this.slides[i];
						$html += '<P>';  
						if (slide.link) { $html += '<a href="' + slide.link + '">'; }  
						//$html += '<img src="' + slide.src + '" ALT="slideshow image">';
						$html += '<img src="' + slide.src + '" ALT="' + slide.alt + '">'; //==>
						if (slide.link) {$html += "<\/a>"; }
						if (slide.text) { $html += "<BR>\n" + slide.text; }
						$html += "<\/P>" + "\n\n";
				}
				$html = $html.replace(/\&/g, "&amp;" );
				$html = $html.replace(/</g, "&lt;" );
				$html = $html.replace(/>/g, "&gt;" );		
				return('<pre>' + $html + '</pre>');
		}
		
		this.loop = function() 
		{
								
				if (this.current < this.slides.length - 1) 
				{
						next_slide = this.slides[this.current + 1];
						if (next_slide.image.complete == null || next_slide.image.complete) { this.next(); }
				} 
				else { 	this.next();}
				this.play( );
		}
				
		this.valid_image = function() 
		{
				if (!this.image){	return false;	}
				else {	return true;}
		}
		
		this.getElementById = function(element_id) 
		{
				if (document.getElementById) { return document.getElementById(element_id); }
				else if (document.all) { return document.all[element_id]; }
				else if (document.layers) { return document.layers[element_id]; } 
				else { return undefined; }
		}
		  
		this.set_image = function(imageobject) 
		{
				if (!document.images) 
				return;
				this.image = imageobject;
		}
		
		this.set_textarea = function(textareaobject) 
		{
				this.textarea = textareaobject;
				this.display_text();
		}
		  
		this.set_textid = function(textidstr) 
		{
				this.textid = textidstr;
				this.display_text();
		}
}