// Slideshow/image viewer JavaScript - 29/9/09

var image_array = new Array()
var image_names = new Array()
var image_index = 0
var next_image_index = 1
var full_image
var interval_id
var slideshow_running = false

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++; 
        } 
    } 
}

function changeOpac(opacity, id) {
	//change the opacity for different browsers
    var object = document.getElementById(id).style; 
    object.opacity = (opacity / 100); 
    object.MozOpacity = (opacity / 100); 
    object.KhtmlOpacity = (opacity / 100); 
    object.filter = "alpha(opacity=" + opacity + ")"; 
}

function start_slideshow() {
	interval_id = setInterval("next_slide()", 5000 )
	slideshow_running = true
	next_slide()
}

function stop_slideshow() {
	clearInterval(interval_id)
	slideshow_running = false
}

function next_slide() {

	var fullPath
	var lastSlash
	
    // Increment the array index
    image_index++
    
    // Are we past the last item?
    if (image_index == image_array.length) {
    
        // If so, set it to 0 to start at the beginning
        image_index = 0
    }
    
    // Display the new image
    changeOpac(0,"image_holder")
    if (image_array[image_index].src == "") {
    	// If image is not preloaded - could happen if linking directly to image - then load it now
    	image_array[image_index].src = image_names[image_index]
    }
    document.images["image_holder"].src = image_array[image_index].src
    fullPath = image_array[image_index].src
    lastSlash = fullPath.lastIndexOf("/")
    document.getElementById("imageRefID").innerHTML = fullPath.substring(lastSlash+1, fullPath.length-4)
    
    // Load the next image
	next_image_index=image_index+1
	if (next_image_index == image_names.length) {
		next_image_index = 0
	}
	if (image_array[next_image_index].src == "") {
		// Preload the image if it's not already in the image_array
		image_array[next_image_index].src = image_names[next_image_index]
	}
    
}

function next_image() {
	document.images["start_stop"].src = "../graphics/start.gif";
	stop_slideshow()
	var fullPath
	var lastSlash
    // Increment the array index
    image_index++
    
    // Are we past the last item?
    if (image_index == image_array.length) {
    
        // If so, set it to 0 to start at the beginning
        image_index = 0
    }
    
    // Display the new image
    if (image_array[image_index].src == "") {
    	// If image is not preloaded - could happen if linking directly to image - then load it now
    	image_array[image_index].src = image_names[image_index]
    }
    document.images["image_holder"].src = image_array[image_index].src
    fullPath = image_array[image_index].src
    lastSlash = fullPath.lastIndexOf("/")
    document.getElementById("imageRefID").innerHTML = fullPath.substring(lastSlash+1, fullPath.length-4)
    
    // Load the next image
	next_image_index=image_index+1
	if (next_image_index == image_names.length) {
		next_image_index = 0
	}
	if (image_array[next_image_index].src == "") {
		// Preload the image if it's not already in the image_array
		image_array[next_image_index].src = image_names[next_image_index]
	}
}

function previous_image() {
	document.images["start_stop"].src = "../graphics/start.gif";
	stop_slideshow()
	var fullPath
	var lastSlash
    // Decrement the array index
    image_index--
    
    // Is the index negative?
    if (image_index < 0) {
    
        // If so, set it to the last element in the array
        image_index = image_array.length - 1
    }
    // Display the new image
    if (image_array[image_index].src == "") {
    	// If image is not preloaded - could happen if linking directly to image - then load it now
    	image_array[image_index].src = image_names[image_index]
    }
    document.images["image_holder"].src = image_array[image_index].src
    fullPath = image_array[image_index].src
    lastSlash = fullPath.lastIndexOf("/")
    document.getElementById("imageRefID").innerHTML = fullPath.substring(lastSlash+1, fullPath.length-4)
    
	// Load previous image ready for navigation
	next_image_index=image_index-1
	if (next_image_index<0) {
		next_image_index = image_names.length-1
	}
	if (image_array[next_image_index].src == "") {
		// Preload the image if it's not already in the image_array
		image_array[next_image_index].src = image_names[next_image_index]
	}
}

function show_picref() {
	document.getElementById("imageRefID").innerHTML = (full_image.substring(7, full_image.length -4));
	GetImageIndex()
}

function toggle_button() {
	if (document.images["start_stop"].src.indexOf("start.gif") > 0) {
		document.images["start_stop"].src = "../graphics/stop.gif";
		start_slideshow()
	}
	else {
		document.images["start_stop"].src = "../graphics/start.gif";
		stop_slideshow()
	}
}

function fade_up(id, millisec) {
	// fade image from 0% to 100% visible
	var speed = Math.round(millisec / 100);
	var timer = 0;
	for(i = 0; i <= 100; i++) { 
        setTimeout("changeOpac(" + i + ",'" + id + "')",(timer * speed)); 
        timer++; 
    }
}

function GetImageIndex() {
	// Get index of image chosen from thumbnails page - all navigation starts from this index
	
	for (var n = 0; n < image_names.length; n++) {
		if (image_names[n] == full_image) {
			image_index = n
		}
	}
}

function ImageLoadEvent() {
	if (slideshow_running) {
		fade_up("image_holder",500);
	}
}

// Example of what needs to follow:

// image_array[0] = new Image()
// image_names[0] = 'images/D300_1873.jpg'
// image_array[1] = new Image()
// image_names[1] = 'images/D300_4740.jpg'
// etc ...

image_array[0] = new Image()
image_names[0] = 'images/D300_0147.jpg'
image_array[1] = new Image()
image_names[1] = 'images/D300_1360.jpg'
image_array[2] = new Image()
image_names[2] = 'images/D300_1390.jpg'
image_array[3] = new Image()
image_names[3] = 'images/D300_1594.jpg'
image_array[4] = new Image()
image_names[4] = 'images/D300_2756.jpg'
image_array[5] = new Image()
image_names[5] = 'images/D300_3303.jpg'
image_array[6] = new Image()
image_names[6] = 'images/D300_3770.jpg'
image_array[7] = new Image()
image_names[7] = 'images/D300_3802.jpg'
image_array[8] = new Image()
image_names[8] = 'images/D300_3817.jpg'
image_array[9] = new Image()
image_names[9] = 'images/D300_3862.jpg'
image_array[10] = new Image()
image_names[10] = 'images/D300_3886.jpg'
image_array[11] = new Image()
image_names[11] = 'images/D300_4014-2.jpg'
image_array[12] = new Image()
image_names[12] = 'images/D300_4622.jpg'
image_array[13] = new Image()
image_names[13] = 'images/D300_4750.jpg'
image_array[14] = new Image()
image_names[14] = 'images/D300_4763.jpg'
image_array[15] = new Image()
image_names[15] = 'images/D300_4811.jpg'
image_array[16] = new Image()
image_names[16] = 'images/D300_4828.jpg'
image_array[17] = new Image()
image_names[17] = 'images/D300_4831.jpg'
image_array[18] = new Image()
image_names[18] = 'images/D300_5054.jpg'
image_array[19] = new Image()
image_names[19] = 'images/D300_6051.jpg'
image_array[20] = new Image()
image_names[20] = 'images/D300_6172.jpg'
image_array[21] = new Image()
image_names[21] = 'images/D300_6454.jpg'
image_array[22] = new Image()
image_names[22] = 'images/D300_6470.jpg'
image_array[23] = new Image()
image_names[23] = 'images/D300_7182.jpg'
image_array[24] = new Image()
image_names[24] = 'images/D300_7224.jpg'
image_array[25] = new Image()
image_names[25] = 'images/D300_7651.jpg'
image_array[26] = new Image()
image_names[26] = 'images/D300_7664.jpg'
image_array[27] = new Image()
image_names[27] = 'images/D300_9948.jpg'
image_array[28] = new Image()
image_names[28] = 'images/D301_0153.jpg'
image_array[29] = new Image()
image_names[29] = 'images/D301_0343.jpg'
image_array[30] = new Image()
image_names[30] = 'images/D301_0921.jpg'
image_array[31] = new Image()
image_names[31] = 'images/D301_1969.jpg'
image_array[32] = new Image()
image_names[32] = 'images/D301_2050.jpg'
image_array[33] = new Image()
image_names[33] = 'images/D301_2141.jpg'
image_array[34] = new Image()
image_names[34] = 'images/D301_2146.jpg'
image_array[35] = new Image()
image_names[35] = 'images/D301_2159.jpg'
image_array[36] = new Image()
image_names[36] = 'images/D40_0622.jpg'
image_array[37] = new Image()
image_names[37] = 'images/D80_1724.jpg'
image_array[38] = new Image()
image_names[38] = 'images/D80_1741.jpg'
image_array[39] = new Image()
image_names[39] = 'images/D80_1752.jpg'
image_array[40] = new Image()
image_names[40] = 'images/D80_1764.jpg'
image_array[41] = new Image()
image_names[41] = 'images/D80_1825.jpg'
image_array[42] = new Image()
image_names[42] = 'images/D80_2562.jpg'
image_array[43] = new Image()
image_names[43] = 'images/D80_2645.jpg'
image_array[44] = new Image()
image_names[44] = 'images/D80_6504.jpg'

// END