<h1>Things to do</h1>
<h2></h2>
<div id="app">
	<form>
		<input
			autocomplete="off"
			type="text"
			name="item"
			class="item"
			placeholder="Add new item...">
		<button type="submit">+ Add</button>
	</form>
	<ul></ul>
</div>

* {
	margin: 0;
	padding: 0;
}

ul {
	list-style: none;
}

html, body {
	background: #CB356B;
	background: -webkit-linear-gradient(to right, #BD3F32, #CB356B);
	background: linear-gradient(to right, #BD3F32, #CB356B);
}

body {
	padding: 20px;
	-webkit-font-smoothing: antialiased;
}

body,
button,
input {
	font-family: -apple-system,system-ui,BlinkMacSystemFont,"Segoe UI",Roboto,"Helvetica Neue",Arial,sans-serif;
	line-height: 1.2;
}

#app {
	margin: 0 auto;
	max-width: 440px;
	position: relative;
}

#app:before {
	background: #fff;
	content: ' ';
	display: block;
	height: 10px;
	opacity: .5;
	width: 420px;
	top: -10px;
	left: 10px;
	position: absolute;
}

#app:after {
	background: #fff;
	content: ' ';
	display: block;
	height: 10px;
	opacity: .3;
	width: 400px;
	top: -20px;
	left: 20px;
	position: absolute;
}

h1,
h2 {
	color: #fff;
	font-size: 24px;
	font-weight: 300;
	margin: 0 auto;
	max-width: 420px;
	opacity: .5;
	text-align: center;
}

h2 {
	font-size: 32px;
	opacity: 1;
	padding: 0 0 40px;
}

form {
	background: transparent;
	position: ;
	transition: all linear .1s;
}

form input {
	background: rgba(255,255,255,.7);
	border: 0;
	box-sizing: border-box;
	display: block;
	font-size: 18px;
	line-height: 50px;
	height: 50px;
	padding: 0 10px;
	position: relative;
	transition: all linear .1s;
	width: 440px;
}

form.focus {
	background: #3F1E24;
	padding: 10px 0;
}

form.focus input {
	background: #fff;
	margin-left: -10px;
	width: 460px;
}

form.focus button {
	top: 25px;
	right: 5px;
}

form input:focus,
form button:focus,
li button:focus {
	outline: none;
}

form button {
	background: transparent;
	border: 0;
	color: #000;
	cursor: pointer;
	font-weight: 600;
	font-size: 18px;
	opacity: .3;
	position: absolute;
	transition: all linear .1s;
	top: 15px;
	right: 15px;
}

form.valid button {
	color: #BD3F32;
	opacity: 1;
}

li {
	background: #FFFFFF;
	border-top: 1px solid #CB356B;
	height: 50px;
	line-height: 50px;
	padding: 0 15px 0 50px;
	position: relative;
}

li button {
	background: #FF4954;
	bottom: 0;
	border: none;
	border-radius: 100%;
	color: #FF4954;
	cursor: pointer;
	font-size: 14px;
	font-weight: 400;
	line-height: 10px;
	opacity: 0;
	position: absolute;
	transition: all ease-in .2s;
	right: 13px;
	top: 13px;
	transform-origin: 0 0;
    width: 24px;
    height: 24px;
}

li button:before {
  content: ' ';
  display: block;
  position: absolute;
  -webkit-transform: rotate(-45deg);
  -moz-transform: rotate(-45deg);
  -o-transform: rotate(-45deg);
  transform: rotate(-45deg);
  width: 12px;
  opacity: 1;
  border-top: solid white 2px;
  top: 11px;
  left: 6px;
}

li button:after {
  content: ' ';
  display: block;
  position: absolute;
  -webkit-transform: rotate(45deg);
  -moz-transform: rotate(45deg);
  -o-transform: rotate(45deg);
  transform: rotate(45deg);
  width: 12px;
  opacity: 1;
  border-top: solid white 2px;
  top: 11px;
  left: 6px;
}

li:hover button {
	opacity: 1;
}

li input[type='checkbox'] {
	cursor: pointer;
    width: 20px;
    height: 20px;
	position: absolute;
	left: 15px;
	top: 15px;
}

li input[type='checkbox']:before {
	border: 2px solid #9d9d9d;
	border-radius: 100%;
    content: '';
    margin-right: 10px;
    display: inline-block;
    vertical-align: text-top;
    width: 20px;
    height: 20px;
    left: -2px;
    position: absolute;
    top: -2px;
    background: white;
}

li.done input[type='checkbox']:before {
	border-color: #005500;
}

li.done input[type='checkbox']:after {
    content: '';
    position: absolute;
    left: 5px;
    top: 10px;
    background: #005500;
    width: 2px;
    height: 2px;
    -webkit-box-shadow: 2px 0 0 #005500, 4px 0 0 #005500, 4px -2px 0 #005500, 4px -4px 0 #005500, 4px -6px 0 #005500, 4px -8px 0 #005500;
    box-shadow: 2px 0 0 #005500, 4px 0 0 #005500, 4px -2px 0 #005500, 4px -4px 0 #005500, 4px -6px 0 #005500, 4px -8px 0 #005500;
    -webkit-transform: rotate(45deg);
    transform: rotate(45deg);
}

.done {
	border-top: 1px solid #97A79B;
	background: #D7E7DB;
	color: #005500;
	text-decoration: line-through;
}

@media (max-width: 560px) {
	#app {
		max-width: 340px;
	}
	#app:before {
		width: 320px;
	}
	#app:after {
		width: 300px;
	}
	body {
		padding: 20px;
	}
	form input {
		width: 340px;
	}
	form.focus input {
		width: 360px;
	}
}

@media (max-width: 390px) {
	#app {
		max-width: 300px;
	}
	#app:before {
		width: 280px;
	}
	#app:after {
		width: 260px;
	}
	form input {
		width: 300px;
	}
	form.focus input {
		width: 320px;
	}
}

@media (max-width: 340px) {
	#app {
		max-width: 260px;
	}
	#app:before {
		width: 240px;
	}
	#app:after {
		width: 220px;
	}
	form input {
		width: 260px;
	}
	form.focus input {
		width: 280px;
	}
}

;(function(window){

	'use strict';

	class Store {

		constructor(name) {
			let isSupported;
			try {
				window.localStorage.setItem('test', 'test');
				window.localStorage.removeItem('test');
				isSupported = true;
			} catch(e) {
				isSupported = false;
			}
			this.name = name;
			this.isSupported = isSupported;
		}

		save(items) {
			const json = JSON.stringify(items);
			window.localStorage.setItem(this.name, json)
		}

		load() {
			const items = window.localStorage.getItem(this.name);
			return (items && items.length) ? JSON.parse(items) : [];
		}

	}

	window.Store = Store;

})(window);

;(function(window, Store){

	'use strict';

	class State {

		constructor(name) {
			this.itemId = 1;
			this.date = this.setDate();
			this.form = {
				focus: false,
				valid: false
			};
			this.items = [];
			this.store = new Store(name);
			if (this.store.isSupported) {
				this.items = this.store.load();
			}
			if (this.items.length) {
				for (const item of this.items) {
					if (item.id >= this.itemId) {
						this.itemId = item.id + 1;
					}
				}
			}
			this.orderItems();
		}

		saveItems() {
			if (this.store.isSupported) {
				this.store.save(this.items);
			}
		}

		addItem(item) {
			this.items.unshift({
				id: this.itemId++,
				status: 0,
				value: item
			});
			this.saveItems();
		}

		orderItems() {
			const todo = this.items.filter((item) => {
				return item.status === 0;
			});
			const done = this.items.filter((item) => {
				return item.status === 1;
			});
			this.items = todo.concat(done);
		}

		findItemIndex(id) {
			return this.items.findIndex((item) => {
				return item.id === id;
			});
		}

		deleteItem(id) {
			const itemIndex = this.findItemIndex(id);
			this.items.splice(itemIndex, 1);
			this.saveItems();
		}


		toggleItemStatus(id) {
			const itemIndex = this.findItemIndex(id);
			this.items[itemIndex].status = this.items[itemIndex].status ? 0 : 1;
			this.orderItems();
			this.saveItems();
		}

		setDate() {
			const date = new Date();
			const monthNames = [
				'January', 'February', 'March',
				'April', 'May', 'June', 'July',
				'August', 'September', 'October',
				'November', 'December'
			];
			let day = date.getDate();
			let monthIndex = date.getMonth();
			let year = date.getFullYear();
			return day + ' ' + monthNames[monthIndex] + ' ' + year;
		}

	}

	window.State = State;

})(window, window.Store);

;(function(State){

	'use strict';

	class App {

		constructor(name) {
			this.name = name;
			this.state = new State(name);
			this.date = document.querySelector('h2');
			this.list = document.querySelector('ul');
			this.button = document.querySelector('button');
			this.form = document.querySelector('form');
			this.input = document.querySelector('input');
			this.bindEvents();
			this.render();
		}

		bindEvents() {
			this.list.addEventListener('click', this.handleClick.bind(this));
			this.form.addEventListener('submit', this.submitForm.bind(this));
			this.input.addEventListener('keyup', this.keyUp.bind(this));
			this.input.addEventListener('focus', this.focus.bind(this));
			this.input.addEventListener('blur', this.blur.bind(this));
			this.button.addEventListener('focus', this.focus.bind(this));
			this.button.addEventListener('blur', this.blur.bind(this));
		}

		submitForm(event) {
			event.preventDefault();
			if (!this.input.value.length) {
				return;
			}
			this.state.addItem(this.input.value);
			this.input.value = '';
			this.render();
		}

		handleClick(event) {
			const e = event;
			if (e && e.target) {
				const element = e.target.type;
				if (element == 'submit' || element == 'checkbox') {
					const id = parseInt(e.target.parentNode.getAttribute('data-id'));
					if (element == 'submit') {
						this.state.deleteItem(id);
					} else {
						this.state.toggleItemStatus(id);
					}
				}
			}
			this.render();
		}

		render() {
			let listHTML = '';
			for (const item of this.state.items) {
				const className = item.status ? 'done' : '';
				listHTML += '<li class="' + className + '" data-id="' + item.id + '">';
				listHTML += '<input type="checkbox"' + (item.status ? ' checked' : '') + '>';
				listHTML += item.value + '<button>x</button></li>';
			}

			this.date.innerHTML = this.state.date;
			this.form.classList.toggle('focus', this.state.form.focus);
			this.form.classList.toggle('valid', this.state.form.valid);
			this.list.innerHTML = listHTML;
		}

		keyUp() {
			this.state.form.valid = (this.input.value.length) ? 1 : 0;
			this.render();
		}

		blur() {
			this.state.form.focus = 0;
			this.render();
		}

		focus() {
			this.state.form.focus = 1;
			this.render();
		}

	}

	const app = new App('todo-list-state-example');

})(window.State);