basic dom functionality implemented with prototype

jsCoreDomFunctions.js

document.addEventListener("DOMContentLoaded", function(){
    // write your script here 
    var demo = _("demo");
    demo.html("Hello").addClass("hi").attr('data-name','test')
    	.css('background-color-is-','black');
    // demo.addClass("your anme");
    // demo.fadeIn();
    // demo.remove();
    // demo.hide();
    console.log(demo);
});



function _(id){return document.getElementById(id);}
function get(selector){
	var elms = document.querySelectorAll(selector);
	if(elms != null && elms.length === 1){
		return elms[0];
	}
	return elms;
}
function log(o){console.log(o);}
function warn(o){console.warn(o);}
function err(o){console.error(o);}
function parseCssRule(rule){
	var needToCheck = true;
	var newArr = [];
	while(needToCheck){
		var index = rule.indexOf("-");
		if(index > 0){
			rule = rule.replace("-", "");
			var upcase = rule[index] ? rule[index].toUpperCase(): '';
			newArr = rule.split("");
			newArr[index] ? newArr[index] = upcase : '';
			rule = newArr.join("");
		}else{
			needToCheck = false;
		}
	}
	return rule;
}
HTMLElement.prototype.val = function(val){
    if(!val){
        return this.value;
    }else{
        this.value = val;
    }
	return this;
}
HTMLElement.prototype.attr = function(attr, val){
	if(!val){
		return this.getAttribute(attr);
	}else{
		this.setAttribute(attr, val);
	}
	return this;
}
HTMLElement.prototype.get = function(selector){
	var elms = this.querySelectorAll(selector);
	if(elms != null && elms.length === 1){
		return elms[0];
	}
	return elms;
}
HTMLElement.prototype.before = function(html){
	this.insertAdjacentHTML('beforebegin', html);
	return this;
}
HTMLElement.prototype.after = function(html){
	this.insertAdjacentHTML('afterend', html);
	return this;
}
HTMLElement.prototype.remove = function(){
	this.parentNode.removeChild(this);
}
HTMLElement.prototype.fadeIn = function(){
  this.style.opacity = 0;
  var last = +new Date();
  var tick = function() {
	this.style.opacity = +this.style.opacity + (new Date() - last) / 400;
	last = +new Date();

	if (+el.style.opacity < 1) {
	  (window.requestAnimationFrame && requestAnimationFrame(tick)) || setTimeout(tick, 16);
	}
  };
  tick();
  return this;
}
HTMLElement.prototype.on = function(evtname, listener){
	this.addEventListener(evtname, listener);
	return this;
}
HTMLElement.prototype.hide = function(){
	this.css('display', 'none');
	return this;
}
HTMLElement.prototype.show = function(){
	this.css('display', 'block');
	return this;
}
HTMLElement.prototype.html = function(val){
	if(!val){
        return this.innerHTML;
    }else{
        this.innerHTML = val;
    }
	return this;
}
HTMLElement.prototype.css = function(css, val){
	var rule = parseCssRule(css);
	if(!val){
        return this.style[rule];
    }else{
        this.style[rule] = val;
    }
	return this;
}
HTMLElement.prototype.addClass = function(className){
	if (this.classList){
	  this.classList.add(className);
	}else{
	  this.className += ' ' + className;
	}
	return this;
}
HTMLElement.prototype.removeClass = function(className){
	if (this.classList){
	  this.classList.remove(className);
	} else {
	  this.className = this.className.replace(new RegExp('(^|\\b)' + className.split(' ').join('|') + '(\\b|$)', 'gi'), ' ');
	}
	return this;
}
HTMLElement.prototype.hasClass = function(className){
	if (this.classList){
	  return this.classList.contains(className);
	}else{
	  return new RegExp('(^| )' + className + '( |$)', 'gi').test(this.className)
	}
}
HTMLElement.prototype.toggleClass = function(className){
	if(this.hasClass(className)){
		this.removeClass(className);
	}else{
		this.addClass(className);
	}
	return this;
}