/*global */

(function() {
  // http://paulirish.com/2011/requestanimationframe-for-smart-animating/
  // http://my.opera.com/emoller/blog/2011/12/20/requestanimationframe-for-smart-er-animating
  // requestAnimationFrame polyfill by Erik Möller. fixes from Paul Irish and Tino Zijdel
  // MIT license
  var lastTime = 0;
  var vendors = ['ms', 'moz', 'webkit', 'o'];
  for(var x = 0; x < vendors.length && !window.requestAnimationFrame; ++x) {
    window.requestAnimationFrame = window[vendors[x]+'RequestAnimationFrame'];
    window.cancelAnimationFrame = window[vendors[x]+'CancelAnimationFrame'] ||
                                  window[vendors[x]+'CancelRequestAnimationFrame'];
  }

  if (!window.requestAnimationFrame) {
    window.requestAnimationFrame = function(callback, element) {
      var currTime = new Date().getTime();
      var timeToCall = Math.max(0, 16 - (currTime - lastTime));
      var id = window.setTimeout(function() { callback(currTime + timeToCall); }, 
        timeToCall);
      lastTime = currTime + timeToCall;
      return id;
    };
  }

  if (!window.cancelAnimationFrame) {
    window.cancelAnimationFrame = function(id) {
      clearTimeout(id);
    };
  }
}());

Element.prototype.hasClassName = function (a) {
    return new RegExp("(?:^|\\s+)" + a + "(?:\\s+|$)").test(this.className);
};

Element.prototype.addClassName = function (a) {
    if (!this.hasClassName(a)) {
        this.className = [this.className, a].join(" ");
    }
};

Element.prototype.removeClassName = function (b) {
    if (this.hasClassName(b)) {
        var a = this.className;
        this.className = a.replace(new RegExp("(?:^|\\s+)" + b + "(?:\\s+|$)", "g"), " ");
    }
};

Element.prototype.toggleClassName = function (a) {
  this[this.hasClassName(a) ? "removeClassName" : "addClassName"](a);
};


function toDegrees (angle) {
  return angle * (180 / Math.PI);
}

function toRadians (angle) {
  return angle * (Math.PI / 180);
}

function deadCenter(){
  var el = document.querySelectorAll('#main')[0];
  el.style.lineHeight = window.innerHeight+'px';
}

var Shoreditch = function( elem ) {
  
  this.elem = elem;
  this.panes = parseInt( this.elem.getAttribute('data-panes'), 15 );
  
  this.colorTime = ~~( Math.random() * 360 );
  this.waveTheta = 0;

  this.colorIncrement = -1;
  this.degrees = 1;

  this.animate();
};

Shoreditch.prototype.getTextShadow = function( x, y, blur, hue, alpha ) {
  return ', ' + x + 'px ' + y + 'px ' + blur + 'px ' + 'hsla(' + hue + ', 100%, 45%, ' + alpha + ')';
};

Shoreditch.prototype.animate = function() {
  var shadows = '0 0 transparent',
      i, j, x, y;
  this.degrees  = (this.degrees !== void 0) ? this.degrees - 1 : 0;
  // renders rainbow river
  for ( i = 1; i < this.panes; i++ ) {
    var normI = i / this.panes;
    var hue = ( normI * 50 + this.colorTime * 0.5 ) % 360;
    var alpha = ( 1 - normI ) * 0.8;
    x = Math.cos(toRadians(this.degrees + i*Math.PI*Math.PI)) * i*(i/10);
    // x = 0;
    y = Math.sin(toRadians(this.degrees + i*Math.PI*Math.PI)) * i*(i*2);
    shadows += this.getTextShadow( x, y, i*(i/5), hue, alpha );
  }

  this.elem.style.textShadow = shadows;
  this.colorTime += this.colorIncrement;
  window.requestAnimationFrame( this.animate.bind( this ) );
};

window.addEventListener( 'resize', deadCenter );

window.addEventListener( 'DOMContentLoaded', function() {
  deadCenter();
	var grov = new Shoreditch(document.querySelectorAll('#txt')[0]);
}, false );