jQuery(document).ready(function() { fadeThumbs(); })
var cur_first = 4;
var direction = '';
var cur_pos = 0;
var cur_max = 0;

function opacity(id, opacStart, opacEnd, millisec) { 
    //speed for each frame 
    var speed = Math.round(millisec / 100); 
    var timer = 0; 

    //determine the direction for the blending, if start and end are the same nothing happens 
    if(opacStart > opacEnd) { 
        for(i = opacStart; i >= opacEnd; i--) { 
            setTimeout("changeOpac(" + i + ",'" + id + "')",(timer * speed)); 
            timer++; 
        } 
    } else if(opacStart < opacEnd) { 
        for(i = opacStart; i <= opacEnd; i++) 
            { 
            setTimeout("changeOpac(" + i + ",'" + id + "')",(timer * speed)); 
            timer++; 
        } 
    } 
} 

//change the opacity for different browsers 
function changeOpac(opacity, id) { 
	if(id != 'main-img'){
		//alert(id);
    //var object = document.getElementById(id).style; 
		var object = $('#'+id);
    object.opacity = (opacity / 100); 
    object.MozOpacity = (opacity / 100); 
    object.KhtmlOpacity = (opacity / 100); 
    object.filter = "alpha(opacity=" + opacity + ")"; 
} }


function changePhoto( idx ) {
	var main_img = document.getElementById( 'main-img' );
	main_img.src = photos['photo_'+idx];
	changeOpac( 0, 'main-img' );
	opacity( 'main-img', 0, 100, 500 );
}

function fadeThumbs() {
	for ( var i=0; i<5; i++ ) {
		changeOpac( 80, 'im_'+i );
	}
}
	
function showNextThumb() {
	if ( cur_pos<cur_max ) {
		opacity('im_'+cur_pos, 0, 80, 70);
		cur_pos++;
		setTimeout('this.showNextThumb()', 70);
	}
}

/* generate navigation */
function fillThumbs( pos, dir ) {
	nav_obj = document.getElementById('thumbs');
	var str='';
	var max = 4;
	
	page = pos/max;
	
	
	if ( dir == 'next' && pos<photos_count ) {
		nav_obj.innerHTML = '';
		
		
		if ( direction == 'prev' ) { pos=pos+max; cur_first=cur_first+max; }
		max = pos;
		pos = pos-3;
		
		//max = 1 + pos;
		cur_max = max;
		cur_pos = pos;
		changePhoto(pos);
		
		//max2 = max;
		//alert(pos+'--'+max);
		if(max>photos_count){ max = photos_count; }
		if(pos<0){ pos = 0; max = 4;}
		
		for ( var i=pos; i<=max; i++) {
			nav_obj.innerHTML += '<a href="javascript://" title=""><span class="div_img"><img id="im_'+i+'" src="'+thumbs['thumb_'+i]+'" onClick="changePhoto('+i+')" onMouseOver="changeOpac( 100, \'im_'+i+'\')" onMouseOut="changeOpac( 80, \'im_'+i+'\')"/></span></a>';
			changeOpac( 0,'im_'+i );
		}
		
		cur_first = cur_first+1;
		direction = 'next';
		if ( max>photos_count ) { cur_first=cur_first-max; }
		
	}
	
	if ( dir == 'prev' && pos>0) {
		nav_obj.innerHTML = '';
		//alert(pos+'--'+max+'---'+cur_first);
		
		if ( pos!=0 ) {
			if ( direction=='next') { pos=pos-max; cur_first=cur_first-max;}
		}
		
		
		
		pos = pos-1;
		max = pos+3;
		
		cur_max = max;
		cur_pos = pos; 
		changePhoto(pos);
	//alert(pos+'--'+max+'---'+cur_first);
		
		for ( var i=pos; i<=max; i++ ) {
			nav_obj.innerHTML += '<a href="javascript://" title=""><span class="div_img"><img id="im_'+i+'" src="'+thumbs['thumb_'+i]+'" onClick="changePhoto('+i+')" onMouseOver="changeOpac( 100, \'im_'+i+'\')" onMouseOut="changeOpac( 80, \'im_'+i+'\')"/></span></a>';
			changeOpac( 0,'im_'+i );
		}
		
		direction = 'prev';
		
		
		cur_first=cur_first-1;
		if ( cur_first<0 ) { cur_first = cur_first+1 };
	}
	showNextThumb();
}