var img_actual = 1;
var num_imgs = 4;
var pe;
function init_transition() {
	pe = new PeriodicalExecuter(transition, 7);
}

function transition() {
	$("img_"+img_actual).fade({duration:2.0});
	if (img_actual == num_imgs) {
		img_actual = 1;
	}
	else {
		img_actual++;
	}
		
	$("img_"+img_actual).appear({duration:2.0});
	for (var i=1; i<=num_imgs; i++) {
		$("ball_"+i).className = "";
	}
	$("ball_"+img_actual).className = "activo";
}

function selectball(id) {
	pe.stop();
	
	$("img_"+img_actual).fade({duration:2.0});
	$("img_"+id).appear({duration:2.0});
	
	for (var i=1; i<=num_imgs; i++) {
		$("ball_"+i).className = "";
	}
	$("ball_"+id).className = "activo";
	img_actual = id;
	pe = new PeriodicalExecuter(transition, 8);
}

var scopes = new Array();
function aclarar(id){
	new Effect.Opacity('img_'+id, {
		from: 0.5,
		to: 1.0,
		duration: 0.3
	});
}
function oscurecer(id){
	new Effect.Opacity('img_'+id, {
		from: 1.0,
		to: 0.5,
		duration: 0.2,
		queue:'end'
	});
}

function gotop(id) {
	Effect.ScrollTo(id, {duration:0.7});
}
function go() {
	var dest = document.location.href;
	if (dest.indexOf('?')) {
		var par = dest.substring(dest.indexOf('=')+1);
		switch(par) {
			case '1':
				Effect.ScrollTo('amargos', {duration:0.7});
				break;
			case '2':
				Effect.ScrollTo('munoz', {duration:0.7});
				break;
		}
	}
}

function enfocar(id) {
	new Effect.Opacity(id, {
		from: 1.0,
		to: 0.0,
		duration: 0.3,
		queue:{scope:'scope_links'}
	});
}
function desenfocar(id) {
	new Effect.Opacity(id, {
		from: 0.0,
		to: 1.0,
		duration: 0.2,
		queue:{position:'end', scope:'scope_links'}
	});
}

function muestranombre(id) {
	switch (id) {
		case 1:
			$("nombre_comp").innerHTML = "Francisco Escoda Patrón (Piano)";
			break;
		case 2:
			$("nombre_comp").innerHTML = "Mario Pérez Blanco (Violín)";
			break;
		case 3:
			$("nombre_comp").innerHTML = "Eduardo Raimundo Beltrán (Clarinete)";
			break;
	}
}

function ocultanombre() {
	$("nombre_comp").innerHTML = "";
}


var pagina_actual = 1;
var num_paginas = 4;
function siguiente() {
	$("anterior").style.visibility = "visible";
	if (pagina_actual < num_paginas) {
		new Effect.Parallel([
		  new Effect.Move("pagina_" + pagina_actual, { sync: true, x: 0, y: 0, mode: 'relative'})
		], { 
			duration: 0.2,
		  	delay: 0
		});
		pagina_actual++;
	}
	if (pagina_actual == num_paginas) {
		$("siguiente").style.visibility = "hidden";
	}
}

function anterior() {
	$("siguiente").style.visibility = "visible";
	if (pagina_actual>1) {
		new Effect.Parallel([
		  new Effect.Move("pagina_" + pagina_actual, { sync: true, x: 0, y: 0, mode: 'relative' })
		], { 
		  duration: 0.2,
		  delay: 0.1
		});
		pagina_actual--;
	}
	if (pagina_actual == 1) {
		$("anterior").style.visibility = "hidden";
	}
}