balazimichal/react-car-counter

## react-car-counter
<!DOCTYPE html>
<html>
  <head>
    <meta charset="UTF-8" />
    <title>Car counter</title>
    <script src="https://unpkg.com/react@16/umd/react.development.js"></script>
    <script src="https://unpkg.com/react-dom@16/umd/react-dom.development.js"></script>
    <script src="https://unpkg.com/babel-standalone@6.15.0/babel.min.js"></script>
  </head>
  <body>
    <div id="root"></div>
    <script type="text/babel">


    class CarCounter extends React.Component {

      constructor(props) {
        super(props);
        this.state = {
          cars : [
          {id: 1, color: 'red', count: -1},
          {id: 2, color: 'green', count: 2},
          {id: 3, color: 'blue', count: 3}
          ],
          value : ''
        };
        this.formChangeHandle = this.formChangeHandle.bind(this);
        this.formSubmitHandle = this.formSubmitHandle.bind(this);
        this.removeHandler = this.removeHandler.bind(this);
        this.addHandler = this.addHandler.bind(this);
        this.deductHandler = this.deductHandler.bind(this);


      }


      removeHandler(c) {
        this.setState(prevState => ({
            cars : prevState.cars.filter((car) => {
                        return car.id !== c.id
                    })
        }))
      }


      addHandler(c) {
        this.setState((prevState) => ({
        cars: prevState.cars.map((car) => {
            if (car.id === c.id) {
            car.count = car.count + 1
            return car
            } else {
            return car
            }
        })
        }))
      }


      deductHandler(c) {
        this.setState((prevState) => ({
        cars: prevState.cars.map((car) => {
            if (car.id === c.id) {
            car.count = car.count - 1
            return car
            } else {
            return car
            }
        })
        }))
      }


      formSubmitHandle(e) {
        e.preventDefault();
        this.setState({
          cars: [...this.state.cars, {id: this.randID(), color: this.state.value, count: 0}],
          value: ''
        });
      }

      formChangeHandle(e) {
        this.setState({ value: e.target.value})
      }

      randID() {
        return Math.random().toString(36).replace(/[^a-z]+/g, '').substr(2, 10);
      }


      render() {
        return (
          <div>
            <h1>Car Counter</h1>
            <p>Add new car color:</p>
            {JSON.stringify(this.state)}

            <form onSubmit={this.formSubmitHandle} onChange={this.formChangeHandle}><input type="text" value={this.state.value} /><input type="submit" value="Add" /></form>
                <ul>
                  {
                    this.state.cars.sort((a, b) => a.count < b.count).map((car) =>
                      <li key={car.id}>{car.color} (ID:{car.id}) ({car.count}) <button onClick={(e) => {this.addHandler(car)}}>+</button><button onClick={(e) => {this.deductHandler(car)}}>-</button><button onClick={(e) => {this.removeHandler(car)}}>Remove</button></li>
                    )
                  }
                </ul>
          </div>
        );
      }
    }


    ReactDOM.render(
      <CarCounter />,
      document.getElementById('root')
    );

    </script>
    <!--
      Note: this page is a great way to try React but it's not suitable for production.
      It slowly compiles JSX with Babel in the browser and uses a large development build of React.

      To set up a production-ready React build environment, follow these instructions:
      * https://reactjs.org/docs/add-react-to-a-new-app.html
      * https://reactjs.org/docs/add-react-to-an-existing-app.html

      You can also use React without JSX, in which case you can remove Babel:
      * https://reactjs.org/docs/react-without-jsx.html
      * https://reactjs.org/docs/cdn-links.html
    -->
  </body>
</html>
	<!DOCTYPE html>
	<html>
	<head>
	<meta charset="UTF-8" />
	<title>Car counter</title>
	<script src="https://unpkg.com/react@16/umd/react.development.js"></script>
	<script src="https://unpkg.com/react-dom@16/umd/react-dom.development.js"></script>
	<script src="https://unpkg.com/babel-standalone@6.15.0/babel.min.js"></script>
	</head>
	<body>
	<div id="root"></div>
	<script type="text/babel">






	class CarCounter extends React.Component {

	constructor(props) {
	super(props);
	this.state = {
	cars : [
	{id: 1, color: 'red', count: -1},
	{id: 2, color: 'green', count: 2},
	{id: 3, color: 'blue', count: 3}
	],
	value : ''
	};
	this.formChangeHandle = this.formChangeHandle.bind(this);
	this.formSubmitHandle = this.formSubmitHandle.bind(this);
	this.removeHandler = this.removeHandler.bind(this);
	this.addHandler = this.addHandler.bind(this);
	this.deductHandler = this.deductHandler.bind(this);


	}


	removeHandler(c) {
	this.setState(prevState => ({
	cars : prevState.cars.filter((car) => {
	return car.id !== c.id
	})
	}))
	}



	addHandler(c) {
	this.setState((prevState) => ({
	cars: prevState.cars.map((car) => {
	if (car.id === c.id) {
	car.count = car.count + 1
	return car
	} else {
	return car
	}
	})
	}))
	}



	deductHandler(c) {
	this.setState((prevState) => ({
	cars: prevState.cars.map((car) => {
	if (car.id === c.id) {
	car.count = car.count - 1
	return car
	} else {
	return car
	}
	})
	}))
	}




	formSubmitHandle(e) {
	e.preventDefault();
	this.setState({
	cars: [...this.state.cars, {id: this.randID(), color: this.state.value, count: 0}],
	value: ''
	});
	}

	formChangeHandle(e) {
	this.setState({ value: e.target.value})
	}

	randID() {
	return Math.random().toString(36).replace(/[^a-z]+/g, '').substr(2, 10);
	}


	render() {
	return (
	<div>
	<h1>Car Counter</h1>
	<p>Add new car color:</p>
	{JSON.stringify(this.state)}

	<form onSubmit={this.formSubmitHandle} onChange={this.formChangeHandle}><input type="text" value={this.state.value} /><input type="submit" value="Add" /></form>
	<ul>
	{
	this.state.cars.sort((a, b) => a.count < b.count).map((car) =>
	<li key={car.id}>{car.color} (ID:{car.id}) ({car.count}) <button onClick={(e) => {this.addHandler(car)}}>+</button><button onClick={(e) => {this.deductHandler(car)}}>-</button><button onClick={(e) => {this.removeHandler(car)}}>Remove</button></li>
	)
	}
	</ul>
	</div>
	);
	}
	}







	ReactDOM.render(
	<CarCounter />,
	document.getElementById('root')
	);

	</script>
	<!--
	Note: this page is a great way to try React but it's not suitable for production.
	It slowly compiles JSX with Babel in the browser and uses a large development build of React.

	To set up a production-ready React build environment, follow these instructions:
	* https://reactjs.org/docs/add-react-to-a-new-app.html
	* https://reactjs.org/docs/add-react-to-an-existing-app.html

	You can also use React without JSX, in which case you can remove Babel:
	* https://reactjs.org/docs/react-without-jsx.html
	* https://reactjs.org/docs/cdn-links.html
	-->
	</body>
	</html>