homework/hw11-promise/script.js

function createBtn(text) {
    let btn = document.createElement('button')
    btn.innerText = `${text}`
    return btn
}

function drawObjTable(parent, obj) {
    let table = document.createElement('table')
    table.border = 1
    table.style.border = '5px double grey'

    let closeRow = document.createElement('tr')

    let closeTd = document.createElement('td')
    closeTd.style.border = 'none'
    
    let closeBtn = createBtn('Close table')
    closeBtn.style.backgroundColor = 'firebrick'
    closeBtn.style.color = 'white'
    closeBtn.onclick = () => parent.removeChild(table)

    closeTd.append(closeBtn)
    closeRow.append(closeTd)
    table.append(closeRow)

    for (let key in obj) {
        let tr = document.createElement('tr')
        let tdKey = document.createElement('td')
        tdKey.innerText = key
        tdKey.style.backgroundColor = 'black'
        tdKey.style.color = 'white'

        let tdValue = document.createElement('td')
        tdValue.style.backgroundColor = 'grey'
        tdValue.style.color = 'whitesmoke'

        if (obj[key].constructor.name === 'Array') {
            for (let item of obj[key]) {
                if (typeof item === 'string' && /^(https:\/\/|http:\/\/)/.test(item)) {
                    let btn = createBtn(`Loading...`)
                    btn.disabled = true

                    fetch(item)
                        .then((res) => {
                            if(res.ok) {
                                return res.json()
                            } else {
                                throw new Error()
                            }
                        })
                        .then(obj => {
                            btn.disabled = false
                            btn.innerText = obj[Object.keys(obj)[0]]
                            btn.onclick = () => { drawObjTable(container, obj) }
                        })
                        .catch(e => console.warn('something bad happened ', e))

                    tdValue.append(btn)
                } else {
                    tdValue.innerText = item
                }
            }
        } else if (typeof obj[key] === 'string' && /^(https:\/\/|http:\/\/)/.test(obj[key])) {
            let btn = createBtn(key)
            btn.disabled = true
        
            fetch(obj[key])
                .then((res) => {
                    if(res.ok) {
                        return res.json()
                    } else {
                        throw new Error()
                    }
                })
                .then(obj => {
                    btn.disabled = false
                    btn.innerText = obj[Object.keys(obj)[0]]
                    btn.onclick = () => { drawObjTable(container, obj) }
                })
                .catch(e => console.warn('something bad happened ', e))

            tdValue.append(btn)
        } else {
            tdValue.innerText = obj[key]
        }

        tr.append(tdKey, tdValue)
        table.append(tr)
    }
    parent.append(table)
}

let container = document.createElement('div')
document.body.append(container)

//luke skywalker
fetch('https://swapi.dev/api/people/1/')
    .then((res) => {
        if(res.ok) {
            return res.json()
        } else {
            throw new Error()
        }
    })
    .then(luke => {
        drawObjTable(container, luke)
    })
    .catch((e) => console.warn('something bad happpened ', e))

// myFetch
function myFetch(url) {
    return new Promise((resolve, reject) => {
        const xhr = new XMLHttpRequest()
        xhr.open('GET', url, true)
        xhr.onreadystatechange = () => {
            if (xhr.readyState != 4){
                return;
            }
        
            if (xhr.status == 200){
                resolve(JSON.parse(xhr.response))
            }
            else {
                reject(new Error(`smth bad happened during request to ${url}. ${xhr.responseText}`))
            }
        }
        xhr.onerror = () => {
            reject(new Error(`smth bad happened during request to ${url}. ${xhr.responseText}`))
        }

        xhr.send()
    })
}

//darth vader
myFetch('https://swapi.dev/api/people/4/')
    .then((res) => {
        drawObjTable(container, res)
    })
    .catch((e) => {console.warn('error occured!', e)})

//let builtIn = fetch('https://swapi.dev/api/people/1/')
let mine = myFetch('https://swapi.dev/api/people/4/')

//при нормальном инете сначал побеждает дилей потом майн всегда
//let delayPromise = delay(300)

//Promise.race([builtIn, mine]).then((value) => console.log('fastest', value))

function delay(ms) {
    return new Promise((resolve, reject) => {
      setTimeout(resolve, ms);
    });
}

//вот таким образом выходит по разному при условии что симулируется slow 3g
//по разному но не 50 на 50. 
let delayPromise = delay(4299)
Promise.race([delayPromise, mine]).then((value) => console.log('fastest:', value || 'delay'))