// ==UserScript==
// @name        OptiFine Download Links
// @namespace   zomo.dev
// @match       https://optifine.net/*
// @grant       none
// @version     1.0
// @author      zomo
// @description automatically grab optifine links through the ads
// @downloadURL https://git.zomo.dev/zomo/browser-scripts/raw/branch/main/dist/optifine-download-links.zomo.js
// @updateURL   https://git.zomo.dev/zomo/browser-scripts/raw/branch/main/dist/optifine-download-links.zomo.js
// ==/UserScript==

const onhover = false // when to load link, false will load immediately

async function getDownload(href: string): Promise<string | null> {
    let resp = await fetch(href)
    let text = await resp.text()
    let match = text.match(/<a href=['"](downloadx.*?)['"]/i)
    if (match) {
        return match[1]
    }
    return null
}

function attachFetchDownloadLink(a: HTMLLinkElement, depth = 0) {
    function run() {
        a.innerText = 'Loading'
        let url = new URL(a.href)
        if (url.pathname === '/adloadx') {
            getDownload(a.href).then(downloadUrl => {
                if (downloadUrl) {
                    a.href = downloadUrl
                    a.innerText = 'Download'
                } else {
                    a.innerText = 'Failed'
                    if (onhover) attachFetchDownloadLink(a, ++depth)
                    else
                        setTimeout(
                            () => attachFetchDownloadLink(a, ++depth),
                            1000
                        )
                }
            })
        }
    }

    if (depth > 5) return

    if (onhover) {
        a.addEventListener('mouseover', run, { once: true })
    } else {
        run()
    }
}

addEventListener('load', () => {
    document.querySelectorAll<HTMLLinkElement>('a').forEach(a => {
        let href = new URL(a.href)
        if (href.hostname === 'adfoc.us') {
            let params = href.searchParams
            if (params.has('url')) {
                let url = params.get('url')?.replace('http://', 'https://')
                if (url) {
                    a.href = url
                    attachFetchDownloadLink(a)
                }
            }
        }
    })
})