LazyMan.html

<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>LazyMan</title>
</head>

<body>
</body>
<script>
    class LazyMan {
        constructor(name) {
            this.name = name;
            console.log(`Hi, I am ${name}`)
            this.taskQueue = []
            setTimeout(() => {
                this.start()
            })
        }

        async start() {
            for (let task of this.taskQueue) {
                await task()
            }
        }

        eat(dinner) {
            this.taskQueue.push(() => {
                console.log(`I am eating ${dinner}`)
            })
            return this;
        }

        wait(time) {
            return () => new Promise(resolve => {
                setTimeout(() => {
                    console.log(`waiting ${time} second`)
                    resolve()
                }, time * 1000)
            })
        }

        sleep(time) {
            this.taskQueue.push(this.wait(time))
            return this;
        }

        sleepFirst(time) {
            this.taskQueue.unshift(this.wait(time))
            return this
        }
    }

    // new LazyMan('test1').sleep(2).eat('lunch')
    // new LazyMan('test2').eat('lunch').sleep(5).eat('dinner')
    new LazyMan('test3').eat('lunch').eat('dinner').sleepFirst(2).sleep(3).eat('junk food')

</script>


</html>