var timer; 
var current_location = 1;
var next_location = 1; 
var pics_loaded = 0;
var onoff = 0;
var direction = 1;
var timeout_value;
var images = new Array;
var photo_urls = new Array;

var transitionNames = new Array;
var transitions = new Array;
var current_transition = 0;

//----- LOOP
//var loop = 0; //--- PARA QUE NO HAYA LOOP
var loop = 1;   //--- PARA QUE SI HAYA LOOP


transitions[0] = "progid:DXImageTransform.Microsoft.Fade(duration=1)";
transitions[1] = "progid:DXImageTransform.Microsoft.Blinds(Duration=1,bands=20)";
transitions[2] = "progid:DXImageTransform.Microsoft.Checkerboard(Duration=1,squaresX=20,squaresY=20)";
transitions[3] = "progid:DXImageTransform.Microsoft.Strips(Duration=1,motion=rightdown)";
transitions[4] = "progid:DXImageTransform.Microsoft.Barn(Duration=1,orientation=vertical)";
transitions[5] = "progid:DXImageTransform.Microsoft.GradientWipe(duration=1)";
transitions[6] = "progid:DXImageTransform.Microsoft.Iris(Duration=1,motion=out)";
transitions[7] = "progid:DXImageTransform.Microsoft.Wheel(Duration=1,spokes=12)";
transitions[8] = "progid:DXImageTransform.Microsoft.Pixelate(maxSquare=10,duration=1)";
transitions[9] = "progid:DXImageTransform.Microsoft.RadialWipe(Duration=1,wipeStyle=clock)";
transitions[10] = "progid:DXImageTransform.Microsoft.RandomBars(Duration=1,orientation=vertical)";
transitions[11] = "progid:DXImageTransform.Microsoft.Slide(Duration=1,slideStyle=push)";
transitions[12] = "progid:DXImageTransform.Microsoft.RandomDissolve(Duration=1,orientation=vertical)";
transitions[13] = "progid:DXImageTransform.Microsoft.Spiral(Duration=1,gridSizeX=40,gridSizeY=40)";
transitions[14] = "progid:DXImageTransform.Microsoft.Stretch(Duration=1,stretchStyle=push)";
transitions[15] = "special case";
var transition_count = 15;
//var photo_count = 5; //----- en el slideshow.html

var slideShowLow = "index.php";
//var slideShowLow = "http://www.cpt.org/gallery/slideshow_low.php?set_albumName=album03";

// Browser capabilities detection ---
// - assume only IE4+ and NAV6+ can do image resizing, others redirect to low 
if (is_ie4up || is_opera5up || is_nav6up) {
    //-- it's all good ---
} else {
    //-- any other browser we go low-tech ---
    document.location = slideShowLow;
}

// - IE5.5 and up can do the blending transition.
var browserCanBlend = (is_ie5_5up);

function stopOrStart() {
    if (onoff) {
	stop();
    } else {
	play();
    }
}

function toggleLoop() {
//    /*
		if (loop) {
	loop = 0;
    } else {
	loop = 1;
    }
//		*/
}

function changeElementText(id, newText) {
    element = document.getElementById(id);
    element.innerHTML = newText;
}

document.all.botonSlideShow = new Image;

function stop() {
    //changeElementText("stopOrStartText", "Iniciar");
    //changeElementText("stopOrStartText", "<img src='images/iniciar-on.gif' border=0 align='absmiddle'>");
    document.all.botonSlideShow.src='images/iniciar-on.gif';

    onoff = 0;
    status = "El slide show está detenido.  Utilice el botón [Iniciar] para volver a ver el slide show.";
    clearTimeout(timer);

}


function play() {
    //changeElementText("stopOrStartText", "Detener");
    //changeElementText("stopOrStartText", "<img src='images/detener-on.gif' border=0 align='absmiddle'>");
    document.all.botonSlideShow.src='images/detener-on.gif';
    
    onoff = 1;
    status = "El slide show está corriendo.  Utilice el botón [Detener] si desea ver las fotos manualmente.";
    go_to_next_photo();
}

function changeDirection() {
    if (direction == 1) {
	direction = -1;
	//changeElementText("changeDirText", "<img src='images/normal-on.gif' border=0 align='absmiddle'>");
    } else {
	direction = 1;
	//changeElementText("changeDirText", "<img src='images/reversa-on.gif' border=0 align='absmiddle'>");
    }
    preload_next_photo();

}

/*
function change_transition() {
    current_transition = document.TopForm.transitionType.selectedIndex;
    play();
}
*/

function preload_complete() {
}


function reset_timer() {
    clearTimeout(timer);
    if (onoff) {
	//timeout_value = document.TopForm.time.options[document.TopForm.time.selectedIndex].value * 1000;
	timeout_value = document.TopForm.time.value * 1000;
	timer = setTimeout('go_to_next_photo()', timeout_value);
    }
}


function wait_for_current_photo() {

    /* Show the current photo */
    if (!show_current_photo()) {

	/*
	 * The current photo isn't loaded yet.  Set a short timer just to wait
	 * until the current photo is loaded.
	 */
	status = "Las imágenes están cargando...(" + current_location + " of " + photo_count +
		").  espere por favor..." ;
	clearTimeout(timer);
	timer = setTimeout('wait_for_current_photo()', 500);
	return 0;
    } else {
	status = "El slide show está corriendo...";
	preload_next_photo();
	reset_timer();
    }
}

function go_to_next_photo() {
    /* Go to the next location */
    if(direction!=1) direction=1;
    current_location = next_location;

    /* Show the current photo */
    if (!show_current_photo()) {
	wait_for_current_photo();
	return 0;
    }

    preload_next_photo();
    reset_timer();
}

function go_to_prev_photo() {
 		//alert('direction: '+direction);
 		if (direction==1)
			changeDirection();
		//alert('eNTRE');
		go_to_next_photo();
	
}

function preload_next_photo() {
    
    /* Calculate the new next location */
    next_location = (parseInt(current_location) + parseInt(direction));
    if (next_location > photo_count) {
	next_location = 1;
	if (!loop) {
	    stop();
	}
    }
    if (next_location == 0) {
        next_location = photo_count;
	if (!loop) {
	    stop();
	}
    }
    
    /* Preload the next photo */
    preload_photo(next_location);
}

function show_current_photo() {

    /*
     * If the current photo is not completely loaded don't display it.
     */
    if (!images[current_location] || !images[current_location].complete) {
	preload_photo(current_location);
	return 0;
    }
    
    /* transistion effects */
    if (browserCanBlend){
	var do_transition;
	if (current_transition == (transition_count)) {
	    do_transition = Math.floor(Math.random() * transition_count);
	} else {
	    do_transition = current_transition;
	}
	document.images.slide.style.filter=transitions[do_transition];
	document.images.slide.filters[0].Apply();
    }
    document.slide.src = images[current_location].src;
    setCaption(photo_captions[current_location]);

    if (browserCanBlend) {
	document.images.slide.filters[0].Play();
    }

    return 1;
}

function preload_photo(index) {

    /* Load the next picture */
    if (pics_loaded < photo_count) {

	/* not all the pics are loaded.  Is the next one loaded? */
	if (!images[index]) {
	    images[index] = new Image;
	    images[index].onLoad = preload_complete();
	    images[index].src = document.getElementById("photo_urls_" + index).href;
	    pics_loaded++;
	}
    } 
}

function setCaption(text) {
    changeElementText("caption", " " + current_location + " de " + photo_count + " ... " + text);
}