var card,
	image,
	cardw,
	cardh,
	cardx,
	cardy,
	ocardx,
	ocardy,
	pinx,
	piny,
	pinxperc,
	pinyperc,
	targetx,
	targety,
	rx,
	ry,
	targetrx,
	targetry,
	scale,
	targetscale,
	ww,
	wh,
	md,
	mx,
	my,
	whoosh,
	whooshvol,
	whooshvoltarget,
	majesty,
	majestyvol,
	majestyvoltarget,
	audioloaded;

function audioload() {
	audioloaded++;
	if( audioloaded == 2 ) {
		document.body.classList.add( 'loaded' );
		majesty.play();
		whoosh.play();
		bindevents();
		loop();
	}
}

function init() {
	onresize();
	card = document.querySelector( '.card' );
	image = document.querySelector( '.card-image' );
	cardw = image.width;
	cardh = image.height;
	cardx = ww / 2 - cardw / 2;
	cardy = wh / 2 - cardh / 2;
	ocardx = cardx;
	ocardy = cardy;
	pinx = 0;
	piny = 0;
	pinxperc = 0;
	pinyperc = 0;
	targetx = cardx;
	targety = cardy;
	rx = 0;
	ry = 0;
	targetrx = 0;
	targetry = 0;
	scale = 1;
	targetscale = scale;
	md = false;
	mx = cardx;
	my = cardy;
	audioloaded = 0;
	
	whooshvol = 0;
	whooshvoltarget = 0;
	whoosh = new Audio();
	whoosh.addEventListener( 'canplaythrough', audioload );
	whoosh.src = 'https://s3-us-west-2.amazonaws.com/s.cdpn.io/836/hs-whoosh.ogg';
	whoosh.volume = 0;
	whoosh.loop = true;
	
	majestyvol = 0;
	majestyvoltarget = 0;
	majesty = new Audio();
	majesty.addEventListener( 'canplaythrough', audioload );
	majesty.src = 'https://s3-us-west-2.amazonaws.com/s.cdpn.io/836/hs-majesty.ogg';
	majesty.volume = 0;
	majesty.loop = true;
}

function bindevents() {
	card.addEventListener( 'mousedown', onmousedown );
	window.addEventListener( 'mouseup', onmouseup );
	window.addEventListener( 'mousemove', onmousemove );
	window.addEventListener( 'resize', onresize );
}

function onmousedown( e ) {
	md = true;
	mx = e.pageX;
	my = e.pageY;
	pinx = cardw / 2; // pin to center
	piny = cardh / 2; // pin to center
	//pinx = mx - cardx; // pin to click point
	//piny = my - cardy; // pin to click point
	pinxperc = 100 - ( pinx / cardw ) * 100; // transform based on the pin position
	pinyperc = 100 - ( piny / cardh ) * 100; // transform based on the pin position
}

function onmouseup() {
	md = false;
}

function onmousemove( e ) {
	if( md ) {
		mx = e.pageX;
		my = e.pageY;
	}
}

function onresize() {
	ww = window.innerWidth;
	wh = window.innerHeight;
}

function loop() {
	requestAnimationFrame( loop )
	
	// set new target position
	targetx = mx - cardx - pinx;
	targety = my - cardy - piny;
	
	// lerp to new position
	cardx += targetx * 0.25;
	cardy += targety * 0.25;
	
	// contain card to window bounds
	if( cardx < -cardw / 2 ) {
		cardx = -cardw / 2;
	}
	if( cardx > ww - cardw / 2 ) {
		cardx = ww - cardw / 2;
	}
	if( cardy < -cardh / 2 ) {
		cardy = -cardh / 2;
	}
	if( cardy > wh - cardh / 2 ) {
		cardy = wh - cardh / 2;
	}
	
	// get rotation based on how much card moved
	targetrx = ( ocardy - cardy - rx ) * 3;
	targetry = ( cardx - ocardx - ry ) * 3;
	
	// lock rotation so things don't get too crazy
	targetrx = Math.min( targetrx, 90 );
	targetrx = Math.max( targetrx, -90 );
	targetry = Math.min( targetry, 90 );
	targetry = Math.max( targetry, -90 );
	
	// lerp to new rotation
	rx += targetrx * 0.1;
	ry += targetry * 0.1;
		
	// scale up when the mouse is pressed
	targetscale = md ? 1.2 - scale : 1 - scale;
	scale += targetscale * 0.2;
	
	// apply the transform
	card.style[ 'transform' ] = 'translate3d(' + cardx + 'px, ' + cardy + 'px, 0)';
	image.style[ 'transform-origin' ] = pinxperc + '% ' + pinyperc + '%';
	image.style[ 'transform' ] = 'scale(' + scale + ') rotateY(' + ry + 'deg) rotateX(' + rx + 'deg)';

	majestyvoltarget = md ? 0.2 : 0;
	majestyvol += ( majestyvoltarget - majestyvol ) * 0.1;
	majesty.volume = majestyvol;
	
	whooshvoltarget = ( Math.abs( ( ocardy - cardy ) ) + Math.abs( ( ocardx - cardx ) ) ) * 0.003;
	whooshvol += ( whooshvoltarget - whooshvol ) * 0.1;
	whoosh.volume = Math.min( whooshvol, 1 );
	
	// store the old card position
	ocardx = cardx;
	ocardy = cardy;
}

// pull up a chair by the hearth!
window.onload = init;