const xhr = new XMLHttpRequest()
const URL = 'https://jsonplaceholder.typicode.com/todos/1'
xhr.open('GET',URL)
xhr.send()
xhr.onreadystatechange = function(event) {
    if (xhr.readyState === XMLHttpRequest.DONE) {
        const status = event.target.status
        if (status ===0 || (status>=200 && status <400)){
            const res = event.target.response
            const data = JSON.parse(res)
            console.log(data)
            console.log(data.title)
        }else {
            console.error('Error!')
        }
    } 
}

const URL = 'https://jsonplaceholder.typicode.com/todos/1'

// const responsePromise = axios.get(URL)
// responsePromise
//   .then(function(res){return res.data} )
//   .then(function (x) {console.log(x.title)})


axios.get(URL) //Promise 리턴 
	//data 받아오기 
    .then(res => res.data)
	//data에서 title 뽑기 
    .then(todo => todo.title)
	//title 출력하기 
    .then(title => console.log( title ))
	//문제가 발생하면 에러 뱉기 
    .catch(err => console.error(err)
     .finally(x) => console.log('끝'))

	const URL = 'https://jsonplaceholder.typicode.com/todos/'
    
    // const responsePromise = axios.get(URL)
    // responsePromise
    //   .then(function(res){return res.data} )
    //   .then(function (x) {console.log(x.title)})

    
    axios.get(URL) //Promise 리턴 
	//data 받아오기  
    .then(res => {
      const todoArray = res.data
      const todo = todoArray.find(todo => todo.id === 10)
      return axios.get(`${URL}${todo.id}`)
    } )
    .then(res => console.log(res.data))
	//문제가 발생하면 에러 뱉기 
    .catch(err => console.error(err))
     .finally(x => console.log('끝'))