Mastodon - Open post link in WebUI

mastodon-open-link-in-webui.user.js

// ==UserScript==
// @name         Mastodon - Open post link in WebUI
// @description  Click fa-comment just before URLs in posts, then it shows linked page in WebUI
// @namespace    https://github.com/unarist/
// @downloadURL  https://gist.github.com/unarist/9bed2c719f42853b9588104e6fdb0a20/raw/mastodon-open-link-in-webui.user.js
// @version      0.15
// @author       unarist
// @match        https://*/web/*
// @match        https://mstdn.maud.io/*
// @grant        none
// @run-at       document-idle
// @noframes
// ==/UserScript==

/*

* X/Twitter: popup tweet widget
* Pixiv: popup thumbnail (click to open in new window)
* OS/AP compatible account/post: resolve via Mastodon and open in WebUI

Todo

* use lang on twitter widget

Changelog

v0.15:
* APで流れてくる、textContentがhttps://から始まらないURLに対応
v0.14:
* Mastodon 4.4.0 あたりで FontAwesome が使えなくなっていたっぽいので、Unicode 絵文字に乗り換え
v0.13:
* X (formerly Twitter) のドメイン x.com に対応
v0.12:
* Mastodon 4.0.0rc3 で動かなかったところを直した（マウント待ち、 _reactRootContainer が消えてたのをどうにかした、/web/ 廃止対応）
v0.11:
* Firefox + Greasemonkey で動かないのを修正（unsafeWindowを使わないと_reactRootContainerが見えない）
v0.10:
* Twitter投稿をiframeで埋め込む方法を見つけたのでGM.xmlHttpRequestを捨てた。やったぜ。
v0.9:
* Twitter対応を復活させた（CSPを迂回するためにGM.xmlHttpRequestに手を出した…そしてallow-same-originも必須になっていた…）
* Pixiv対応を復活させた（当時の経緯を忘れたがもう普通のプレビューでいいのでは感ある）
* 多分Mastodon投稿も開けなくなっていたのを修正
v0.8:
* react-redux 6.0.0 (Mastodon 2.7.0) 対応 (c.f. reduxjs/react-redux #1000)
* Twitter: CSPでどうしようもないので当面無効化
v0.7: Twitter: support mobile.twitter.com urls
v0.6: React 16.3 (Mastodon 2.4.0)対応
v0.5: Twitter: fix embed shaking, relax sandbox in Firefox
v0.4: Pixiv: click to open
v0.3: Twitter: fix action buttons, set dnt flag

*/

(async function() {
    'use strict';

    const app_root = (typeof unsafeWindow !== 'undefined' ? unsafeWindow : window).document.querySelector('#mastodon');
    if (!app_root) return;

    const wait = t => new Promise(r => setTimeout(r, t));
    const waitForSelector = async (q, t, max_t) => {
        const until = Date.now() + max_t;
        do {
            const v = document.querySelector(q);
            if (v) return v;
            await wait(t);
        } while (Date.now() < until);
        throw new Error(`waiting for query ${q} has been timed out in ${max_t}ms`);
    };
    // Reactのマウントを待つ
    await waitForSelector(".ui", 200, 2000);

    const cache = {};
    const keys = {
        state: 'webuiLinkState',
        icon: 'webuiLinkIcon',
    };

    const tag = (name, props = {}, children = []) => {
        const e = Object.assign(document.createElement(name), props);
        if (typeof props.style === "object") Object.assign(e.style, props.style);
        (children.forEach ? children : [children]).forEach(c => e.appendChild(c));
        return e;
    };

    const defaultOptions = {
        headers: {
            'Authorization': 'Bearer ' + JSON.parse(document.getElementById('initial-state').textContent).meta.access_token
        }
    };
    const api = (path, options) =>
    fetch(location.origin + path, Object.assign({}, defaultOptions, options)) // should be deepMerge
    .then(resp => { if (!resp.ok) throw new Error(new URL(resp.url).pathname + ' ' + resp.status); return resp.json(); });

    const getHtmlLang = () => document.documentElement.getAttribute('lang');
    const getHistory = () => {
        try {
            const v16_root_node_prop = Object.keys(app_root).find(k => k.startsWith("__reactContainer"));
            if (v16_root_node_prop) {
                // >= v16: to descendant
                let current_node = app_root[v16_root_node_prop];
                while (current_node) {
                    const history = current_node.memoizedProps?.history;
                    if (history) return history;
                    current_node = current_node.child;
                }
            } else {
                // < v16: to ancestor
                const root_instance = Object.entries(app_root.firstElementChild).find(prop=>prop[0].startsWith('__reactInternalInstance'))[1];
                let current_node = root_instance._currentElement._owner;
                while (current_node) {
                    const history = current_node._instance.props.history;
                    if (history) return history;
                    current_node = current_node._currentElement._owner;
                }
            }
        } catch (e) {
            console.log('mastodon-open-link-in-webui: Failed to get History instance: ', e);
            return null;
        }
    };

    const modal = {
        open(elem) {
            this.container.appendChild(elem);
            Object.assign(this.container.style, { display: 'block', opacity: 1 });
        },
        close() {
            this.container.addEventListener('transitionend', () => {
                this.container.style.display = 'none';
                while (this.container.firstChild) this.container.removeChild(this.container.firstChild);
            }, { once: 1 });
            this.container.style.opacity = 0;
        },
        container: tag('div', {
            style: "position:fixed; top:0; width:100%; height:100%; background: rgba(0,0,0,0.8); display:none; z-index: 999; transition: 100ms",
            onclick: e => modal.close(),
            onkeydown: e => e.keyCode === 27 && modal.close()
        })
    };

    document.body.appendChild(modal.container);

    const processors = [];
    processors.push(function() {
        window.addEventListener('message', e => {
            const iframe = document.querySelector('.webui-link-iframe');
            if (iframe && iframe.contentWindow === e.source && e.origin === 'https://platform.twitter.com' && e.data['twttr.embed'].method === 'twttr.private.resize') {
                iframe.style.height = e.data['twttr.embed'].params[0].height + 'px';
                iframe.style.opacity = '1';
            }
        });

        return url => {
            const match = url.match(/\/(?:mobile\.)?(?:twitter|x)\.com\/[^/]+\/status\/(\d+)/);
            if (match)
                return Promise.resolve(() => modal.open(tag('iframe', {
                    className: 'webui-link-iframe',
                    style: `
width: 480px; max-width: 90vw; height: 80vh; max-height: 80vh;
position: absolute; top: 0; left: 0; right: 0; bottom: 0; margin: auto; border: none;
opacity:0; transition: opacity .1s ease-in`,
                    // widget.js の中で使われていた
                    src: `https://platform.twitter.com/embed/index.html?dnt=true&id=${match[1]}`
                })));
            else
                return Promise.resolve();
        };
    }());
    processors.push(url => {
        const match = url.match(/\/www\.pixiv\.net\/.*illust_id=(\d+)/) || url.match(/\/www\.pixiv\.net\/.*artworks\/(\d+)/);
        if (match)
            return Promise.resolve(() => modal.open(tag('a', {
                href: url,
                target: '_blank'
            }, [
                tag('img', {
                    src: `https://embed.pixiv.net/decorate.php?illust_id=${match[1]}&mode=sns-automator`,
                    style: 'max-width: 80vw; max-height: 80vh; position: absolute; top: 0; left: 0; right: 0; bottom: 0; margin: auto;'
                })
            ])));
        else
            return Promise.resolve();
    });
    processors.push(function () {
        const history = getHistory();
        if (!history) return () => Promise.reject();

        const openStatus = id => history.push('/statuses/' + id);
        const openAccount = id => history.push('/accounts/' + id);

        return url => api('/api/v2/search?resolve=true&q=' + url)
            .then(json => {
            if (json.statuses.length) {
                return openStatus.bind(null, json.statuses[0].id);
            } else if (json.accounts.length) {
                return openAccount.bind(null, json.accounts[0].id);
            }
        });
    }());

    const actions = {
        _history: undefined,
        attach(elem) {
            elem.insertBefore(tag('span', { className: keys.icon, style: 'margin-right: .1em', textContent: '💬' }), elem.firstChild);
            elem.addEventListener('click', handleClick);
        },
        detatch(elem) {
            elem.removeChild(elem.querySelector('.' + keys.icon));
            elem.removeEventListener('click', handleClick);
        },
        open(elem) {
            cache[elem.href]();
        },
        refresh(elem) {
            const icon_elem = elem.querySelector('.' + keys.icon);

            elem.dataset[keys.state] = 'refreshing';
            icon_elem.classList.replace('fa-comment', 'fa-spinner');

            const tryNext = (url, rest) => {
                rest[0](url).then(result => {
                    if (result) {
                        elem.dataset[keys.state] = 'found';
                        cache[elem.href] = result;
                        icon_elem.classList.replace('fa-spinner', 'fa-comment');
                        result();
                    } else {
                        if (rest.length > 1) {
                            tryNext(url, rest.slice(1));
                        } else {
                            elem.dataset[keys.state] = 'notfound';
                            actions.detatch(elem);
                        }
                    }
                }).catch(e => (console.log(e), elem.dataset[keys.state] = 'error', actions.detatch(elem)));
            };

            tryNext(elem.href, processors);
        }
    };

    const handleClick = e => {
        if (!e.target.classList.contains(keys.icon)) return;

        const link = e.currentTarget;
        switch (link.dataset[keys.state]) {
            case 'candidate':
                actions.refresh(link);
                break;
            case 'found':
                actions.open(link);
                e.preventDefault();
                break;
        }
        e.preventDefault();
    };

    new MutationObserver(mutations => {
        for (const elem of document.querySelectorAll('.status__content a:not([data-webui-link-state])')) {
            // 2025-09-28: 外来のコンテンツによってはhttpsがなく、最近のWebUIは .unhandled-link を足してそうなので入れた。 .unhandled-link だけでいいかも。
            if (!(elem.textContent.startsWith('https') || elem.classList.contains('unhandled-link')) || cache[elem.href] === null) {
                elem.dataset[keys.state] = 'none';
            } else {
                elem.dataset[keys.state] = cache[elem.href] ? 'found' : 'candidate';
                actions.attach(elem);
            }
        }
    }).observe(app_root, {childList: true, subtree: true});
})();