// ==UserScript==
// @name         水源显示回复可见
// @namespace    CCCC_David
// @version      0.3.1
// @description  可在水源论坛显示仅回复可见的回帖内容
// @author       CCCC_David
// @match        https://shuiyuan.sjtu.edu.cn/*
// @grant        none
// ==/UserScript==
(async () => {
'use strict';
// From Font Awesome Free v5.15 by @fontawesome - https://fontawesome.com
// License - https://fontawesome.com/license/free (Icons: CC BY 4.0, Fonts: SIL OFL 1.1, Code: MIT License)
// Modified class attribute to fit in.
const PREV_REPLY_ICON = '<svg aria-hidden="true" focusable="false" data-prefix="fas" data-icon="caret-left" class="svg-icon" role="img" xmlns="http://www.w3.org/2000/svg" viewBox="0 0 192 512"><path fill="currentColor" d="M192 127.338v257.324c0 17.818-21.543 26.741-34.142 14.142L29.196 270.142c-7.81-7.81-7.81-20.474 0-28.284l128.662-128.662c12.599-12.6 34.142-3.676 34.142 14.142z"></path></svg>';
const NEXT_REPLY_ICON = '<svg aria-hidden="true" focusable="false" data-prefix="fas" data-icon="caret-right" class="svg-icon" role="img" xmlns="http://www.w3.org/2000/svg" viewBox="0 0 192 512"><path fill="currentColor" d="M0 384.662V127.338c0-17.818 21.543-26.741 34.142-14.142l128.662 128.662c7.81 7.81 7.81 20.474 0 28.284L34.142 398.804C21.543 411.404 0 402.48 0 384.662z"></path></svg>';
const LOAD_ALL_REPLIES_ICON = '<svg aria-hidden="true" focusable="false" data-prefix="fas" data-icon="angle-double-right" class="svg-icon" role="img" xmlns="http://www.w3.org/2000/svg" viewBox="0 0 448 512"><path fill="currentColor" d="M224.3 273l-136 136c-9.4 9.4-24.6 9.4-33.9 0l-22.6-22.6c-9.4-9.4-9.4-24.6 0-33.9l96.4-96.4-96.4-96.4c-9.4-9.4-9.4-24.6 0-33.9L54.3 103c9.4-9.4 24.6-9.4 33.9 0l136 136c9.5 9.4 9.5 24.6.1 34zm192-34l-136-136c-9.4-9.4-24.6-9.4-33.9 0l-22.6 22.6c-9.4 9.4-9.4 24.6 0 33.9l96.4 96.4-96.4 96.4c-9.4 9.4-9.4 24.6 0 33.9l22.6 22.6c9.4 9.4 24.6 9.4 33.9 0l136-136c9.4-9.2 9.4-24.4 0-33.8z"></path></svg>';
// Parameters.
const FETCH_MAX_RETRIES = 15;
const EXP_BACKOFF_START = 0.1;
const EXP_BACKOFF_BASE = 1.2;
const ADJUST_AVATAR_SIZE = 90;
const EMPTY_IMG = 'data:image/gif;base64,R0lGODlhAQABAAD/ACwAAAAAAQABAAACADs=';
const INITIAL_REPLY_ID = 1;
const MIN_WAIT_MS_BETWEEN_REPLIES = 600;
const APPEND_VIEWER_TARGET_CLASS = 'post-stream';
// Utility functions.
const escapeRegExpOutsideCharacterClass = (s) => s.replace(/[.*+?^${}()|[\]\\]/gu, '\\$&');
const escapeHtml = (html) => html.replace(/&/gu, '&amp;').replace(/</gu, '&lt;').replace(/>/gu, '&gt;').replace(/"/gu, '&quot;').replace(/'/gu, '&#039;');
// eslint-disable-next-line no-promise-executor-return
const sleep = (ms) => new Promise((resolve) => setTimeout(resolve, ms));
const allowedPolicy = window.trustedTypes?.createPolicy?.('allowedPolicy', {createHTML: (x) => x});
const createTrustedHTML = (html) => (allowedPolicy ? allowedPolicy.createHTML(html) : html);
const htmlParser = new DOMParser();
const generateErrorOneboxR###lt = (msg) => `<aside><blockquote>[color=red](${escapeHtml(msg)})[/color]</blockquote></aside>`;
// Fetch wrapper with:
// - Discourse special headers.
// - Response status code check.
// - Limited exponential backoff retry upon 429 status code.
const discourseFetch = async (url, options) => {
let currentAttempt = 0;
// eslint-disable-next-line no-constant-condition
while (true) {
// eslint-disable-next-line no-await-in-loop
const response = await fetch(url, {
method: options?.method ?? 'GET',
headers: {
'Discourse-Present': 'true',
'Discourse-Logged-In': 'true',
'X-Requested-With': 'XMLHttpRequest',
'X-CSRF-Token': document.querySelector('meta[name=csrf-token]').content,
...options?.headers,
},
body: options?.body,
mode: 'same-origin',
credentials: 'include',
redirect: 'follow',
});
if (response.status === 429) {
currentAttempt += 1;
if (currentAttempt > FETCH_MAX_RETRIES) {
throw new Error('Max retries exceeded');
}
// eslint-disable-next-line no-await-in-loop
await sleep(1000 * EXP_BACKOFF_START * EXP_BACKOFF_BASE ** (currentAttempt - 1));
continue;
}
if (!response.ok) {
throw new Error(`${response.status}${response.statusText ? ` ${response.statusText}` : ''}`);
}
return response;
}
};
const fetchReply = async (topicId, replyId) => {
const replyURL = `/t/topic/${topicId}/${replyId}`;
try {
const response = await discourseFetch(`/onebox?url=${encodeURIComponent(replyURL)}`);
return response.text();
} catch (e) {
return generateErrorOneboxR###lt(e.toString());
}
};
const fetchTopicInfo = async (topicId) => {
const [topicInfo1, topicInfo2] = await Promise.all([
`/t/${topicId}.json`,
`/latest.json?topic_ids=${topicId}`,
].map(async (url) => (await discourseFetch(url, {headers: {Accept: 'application/json'}})).json()));
return {
isPrivateReply: topicInfo1.private_replies,
maxReplyId: topicInfo2.topic_list?.topics?.[0]?.highest_post_number ?? 0,
participants: topicInfo1.details?.participants ?? [],
};
};
const fetchUserInfo = async (username) => {
if (!username) {
return {
error: false,
username: null,
name: null,
title: null,
};
}
try {
const response = await discourseFetch(`/u/${encodeURIComponent(username)}/card.json`, {headers: {Accept: 'application/json'}});
const userInfo = await response.json();
return {
error: false,
username: userInfo.user.username,
name: userInfo.user.name,
title: userInfo.user.title,
};
} catch (e) {
// eslint-disable-next-line no-console
console.error(e);
return {
error: true,
username: null,
name: null,
title: null,
};
}
};
const renderReply = (tree) => {
const blockquote = tree.querySelector('aside > blockquote');
if (!blockquote) {
return '<p>(帖子已被作者删除)</p>';
}
const reply = blockquote.innerHTML.trim();
if (!reply) {
return '<p>&nbsp;</p>';
}
// eslint-disable-next-line no-undef
return require('discourse/lib/text').cookAsync(reply);
};
const getAvatarURLFromReply = (tree) => {
const img = tree.querySelector('aside > div > img');
if (!img) {
return '';
}
// Resize the avatar.
return img.src.replace(/\/user_avatar\/([^/]+)\/([^/]+)\/40\//u, `/user_avatar/$1/$2/${ADJUST_AVATAR_SIZE}/`)
.replace(/\/letter_avatar_proxy\/([^/]+)\/letter\/([^/]+)\/([^/]+)\/40\./u, `/letter_avatar_proxy/$1/letter/$2/$3/${ADJUST_AVATAR_SIZE}.`);
};
const tryToFindUserByAvatar = async (avatarURL, participants) => {
// Case 1: Extract username from URL if it is user avatar.
const username = avatarURL.match(/\/user_avatar\/(?:[^/]+)\/([^/]+)\//u)?.[1];
if (username) {
return {
error: false,
username: decodeURIComponent(username),
name: null,
title: null,
};
}
// Case 2: Try to match letter avatar with top participants of this topic.
const letterAvatarMatch = avatarURL.match(/\/letter_avatar_proxy\/(?:[^/]+)\/letter\/([^/]+)\/([^/]+)\//u); // Letter and color
if (!letterAvatarMatch) { // Unexpected format.
return {
error: false,
username: null,
name: null,
title: null,
};
}
const letterAvatarTag = ['letter', letterAvatarMatch[1], letterAvatarMatch[2]].join('/');
for (const participant of participants) {
if ((participant.avatar_template ?? '').includes(letterAvatarTag)) {
return {
error: false,
username: participant.username,
name: participant.name,
title: null,
};
}
}
// Case 3: Search for users with the letter and try to match letter avatar.
let searchUsersByLetterR###lt;
try {
searchUsersByLetterR###lt = await (await discourseFetch(`/directory_items?period=all&order=username&name=${encodeURIComponent(decodeURIComponent(letterAvatarMatch[1]))}`)).json();
} catch (e) {
// eslint-disable-next-line no-console
console.error(e);
return {
error: true,
username: null,
name: null,
title: null,
};
}
for (const user of searchUsersByLetterR###lt.directory_items) {
if ((user.user.avatar_template ?? '').includes(letterAvatarTag)) {
return {
error: false,
username: user.user.username,
name: user.user.name,
title: user.user.title ?? '',
};
}
}
// We are unable to figure out the username by avatar.
return {
error: false,
username: null,
name: null,
title: null,
};
};
const viewerTemplate = (options) => `
<div class="topic-post clearfix regular">
<article role="region" class="boxed">
<div class="row">
<div class="topic-avatar">
<a ${options.hasElementId ? 'id="show-private-reply-avatar"' : ''} class="trigger-user-card main-avatar" href="${options.userPage}" data-user-card="${options.dataUserCard}" aria-hidden="true" style="${options.avatarStyle}">
<img width="45" height="45" src="${options.avatarURL}" class="avatar" loading="lazy">
</a>
</div>
<div class="topic-body clearfix">
<div role="heading" class="topic-meta-data">
<div class="names trigger-user-card">
<span class="first full-name">
<a ${options.hasElementId ? 'id="show-private-reply-name"' : ''} href="${options.userPage}" data-user-card="${options.dataUserCard}" style="${options.nameStyle}">${options.name}</a>
</span>
<span class="second username" style="${options.usernameStyle}">
<a ${options.hasElementId ? 'id="show-private-reply-username"' : ''} href="${options.userPage}" data-user-card="${options.dataUserCard}">${options.username}</a>
</span>
<span ${options.hasElementId ? 'id="show-private-reply-user-title"' : ''} class="user-title" style="${options.userTitleStyle}">${options.userTitle}</span>
</div>
<span style="text-align: right; margin-left: auto;">
${options.hasElementId ? `
<span id="show-private-reply-id" title="跳转到回复..." style="font-size: var(--font-up-2); cursor: pointer;">${options.replyId}</span>
` : `
<span style="font-size: var(--font-up-2);">${options.replyId}</span>
`}
${options.hasElementId ? `
<button id="show-private-reply-dec-id" class="btn" title="上一条" style="margin-left: 0.5em;">${PREV_REPLY_ICON}</button>
<button id="show-private-reply-inc-id" class="btn" title="下一条" style="margin-left: 0.5em;">${NEXT_REPLY_ICON}</button>
<button id="show-private-reply-load-all" class="btn" title="加载剩余所有回复" style="margin-left: 0.5em;">${LOAD_ALL_REPLIES_ICON}</button>
` : ''}
</span>
</div>
<div class="regular contents">
<div ${options.hasElementId ? 'id="show-private-reply-content"' : ''} class="cooked">${options.content}</div>
</div>
</div>
</div>
</article>
</div>
`;
let viewerInitialized = false;
const addViewer = async (parentNode) => {
if (!parentNode) {
return;
}
// Do not add the viewer more than once for a page.
if (document.getElementById('show-private-reply-div')) {
return;
}
viewerInitialized = false;
const topicId = parseInt(window.location.pathname.match(/^\/t\/topic\/(\d+)(?=\/|$)/u)?.[1], 10);
if (Number.isNaN(topicId)) { // Unable to parse topic ID, maybe not a topic page, give up.
return;
}
const {isPrivateReply, maxReplyId, participants} = await fetchTopicInfo(topicId);
// Do not add viewer if current topic is not private reply.
// Double check for race condition after await.
if (!isPrivateReply || maxReplyId < 1 || document.getElementById('show-private-reply-div')) {
return;
}
const viewerContainer = document.createElement('div');
viewerContainer.id = 'show-private-reply-div';
viewerContainer.style.visibility = 'hidden';
viewerContainer.innerHTML = createTrustedHTML(viewerTemplate({
hasElementId: true,
userPage: '',
dataUserCard: '',
avatarStyle: 'visibility: hidden; cursor: default;',
avatarURL: escapeHtml(EMPTY_IMG),
nameStyle: 'display: none;',
name: '&nbsp;',
usernameStyle: 'display: none;',
username: '',
userTitleStyle: 'display: none;',
userTitle: '',
replyId: INITIAL_REPLY_ID,
content: '<p>正在加载回复可见内容...</p>',
}));
parentNode.appendChild(viewerContainer);
const replyAvatarElement = document.getElementById('show-private-reply-avatar');
const replyNameElement = document.getElementById('show-private-reply-name');
const replyUsernameElement = document.getElementById('show-private-reply-username');
const replyUserTitleElement = document.getElementById('show-private-reply-user-title');
const replyIdElement = document.getElementById('show-private-reply-id');
const replyContentElement = document.getElementById('show-private-reply-content');
const replyLoadAllButton = document.getElementById('show-private-reply-load-all');
let lastGetReplyFullInfoTime = null;
const getReplyFullInfo = async (replyId) => {
// Require a minimum wait time between two fetches of replies.
if (lastGetReplyFullInfoTime) {
const remainingTimeMs = MIN_WAIT_MS_BETWEEN_REPLIES - (new Date() - lastGetReplyFullInfoTime);
if (remainingTimeMs > 0) {
await sleep(remainingTimeMs);
}
}
// eslint-disable-next-line require-atomic-updates
lastGetReplyFullInfoTime = new Date();
const reply = await fetchReply(topicId, replyId);
let tree;
try {
tree = htmlParser.parseFromString(reply, 'text/html');
} catch (e) {
// eslint-disable-next-line no-console
console.error(e);
tree = htmlParser.parseFromString(generateErrorOneboxR###lt('Unable to parse r###lt from `/onebox`'), 'text/html');
}
const avatarURL = getAvatarURLFromReply(tree);
// eslint-disable-next-line no-shadow
let {error, username, name, title} = await tryToFindUserByAvatar(avatarURL, participants);
if (title === null && !error) {
({error, username, name, title} = await fetchUserInfo(username));
}
return {
error,
avatarURL,
username,
name,
title,
content: await renderReply(tree),
};
};
const updateView = async (replyId) => {
// eslint-disable-next-line no-shadow
const {error, avatarURL, username, name, title, content} = await getReplyFullInfo(replyId);
const nameToShow = name || username;
replyAvatarElement.href = replyNameElement.href = replyUsernameElement.href = username ? `/u/${encodeURIComponent(username)}` : '';
for (const userCardElement of [replyAvatarElement, replyNameElement, replyUsernameElement]) {
userCardElement.setAttribute('data-user-card', username ?? '');
// eslint-disable-next-line no-undef
jQuery(userCardElement).data('user-card', username ?? '');
}
replyAvatarElement.children[0].src = avatarURL || EMPTY_IMG;
replyAvatarElement.style.visibility = avatarURL ? 'visible' : 'hidden';
replyAvatarElement.style.cursor = username ? 'pointer' : 'default';
replyNameElement.textContent = error ? '(加载用户信息失败)' : nameToShow || '未知用户的回复';
replyNameElement.style.cursor = nameToShow ? 'pointer' : 'text';
replyNameElement.style.display = '';
replyUsernameElement.textContent = username ?? '';
replyUsernameElement.parentNode.style.display = name && name !== username ? '' : 'none';
replyUserTitleElement.textContent = title ?? '';
replyUserTitleElement.style.display = title ? '' : 'none';
replyIdElement.textContent = replyId.toString();
replyContentElement.innerHTML = createTrustedHTML(content);
};
for (const userCardElement of [replyAvatarElement, replyNameElement, replyUsernameElement]) {
userCardElement.addEventListener('click', (e) => {
if (!userCardElement.getAttribute('data-user-card')) {
e.preventDefault();
e.stopPropagation();
}
});
}
viewerContainer.style.visibility = '';
let replyNavigationInProgress = false;
document.getElementById('show-private-reply-inc-id').addEventListener('click', async () => {
if (!viewerInitialized || replyNavigationInProgress) {
return;
}
let replyId = parseInt(replyIdElement.textContent, 10);
replyId = Math.max(replyId < maxReplyId ? replyId + 1 : 1, 1);
replyNavigationInProgress = true;
try {
await updateView(replyId);
} catch (e) {
// eslint-disable-next-line no-console
console.error(e);
}
// eslint-disable-next-line require-atomic-updates
replyNavigationInProgress = false;
});
document.getElementById('show-private-reply-dec-id').addEventListener('click', async () => {
if (!viewerInitialized || replyNavigationInProgress) {
return;
}
let replyId = parseInt(replyIdElement.textContent, 10);
replyId = Math.min(replyId > 1 ? replyId - 1 : maxReplyId, maxReplyId);
replyNavigationInProgress = true;
try {
await updateView(replyId);
} catch (e) {
// eslint-disable-next-line no-console
console.error(e);
}
// eslint-disable-next-line require-atomic-updates
replyNavigationInProgress = false;
});
replyIdElement.addEventListener('click', async () => {
if (!viewerInitialized || replyNavigationInProgress) {
return;
}
const newReplyIdText = prompt('跳转到回复...', replyIdElement.textContent);
if (!newReplyIdText) {
return;
}
let newReplyId = parseInt(newReplyIdText, 10);
if (Number.isNaN(newReplyId)) {
newReplyId = 1;
}
newReplyId = Math.min(Math.max(newReplyId, 1), maxReplyId);
replyNavigationInProgress = true;
try {
await updateView(newReplyId);
} catch (e) {
// eslint-disable-next-line no-console
console.error(e);
}
// eslint-disable-next-line require-atomic-updates
replyNavigationInProgress = false;
});
replyLoadAllButton.addEventListener('click', async () => {
if (!viewerInitialized) {
return;
}
replyLoadAllButton.style.display = 'none';
let currentReplyId = parseInt(replyIdElement.textContent, 10);
if (Number.isNaN(currentReplyId)) {
currentReplyId = 1;
}
currentReplyId = Math.min(Math.max(currentReplyId, 1), maxReplyId);
const loadingStateNode = document.createTextNode('加载中...');
parentNode.parentNode.appendChild(loadingStateNode);
for (let replyId = currentReplyId + 1; replyId <= maxReplyId; replyId += 1) {
// eslint-disable-next-line no-shadow, no-await-in-loop
const {error, avatarURL, username, name, title, content} = await getReplyFullInfo(replyId);
const nameToShow = name || username;
const replyContainer = document.createElement('div');
replyContainer.style.visibility = 'hidden';
replyContainer.innerHTML = createTrustedHTML(viewerTemplate({
hasElementId: false,
userPage: escapeHtml(username ? `/u/${encodeURIComponent(username)}` : ''),
dataUserCard: escapeHtml(username ?? ''),
avatarStyle: `visibility: ${avatarURL ? 'visible' : 'hidden'}; cursor: ${username ? 'pointer' : 'default'};`,
avatarURL: escapeHtml(avatarURL || EMPTY_IMG),
nameStyle: `cursor: ${nameToShow ? 'pointer' : 'text'};`,
name: escapeHtml(error ? '(加载用户信息失败)' : nameToShow || '未知用户的回复'),
usernameStyle: name && name !== username ? '' : 'display: none;',
username: escapeHtml(username ?? ''),
userTitleStyle: title ? '' : 'display: none;',
userTitle: escapeHtml(title ?? ''),
replyId,
content,
}));
parentNode.appendChild(replyContainer);
for (const selector of ['.main-avatar', '.full-name > a', '.username > a']) {
const userCardElement = replyContainer.querySelector(selector);
// eslint-disable-next-line no-undef
jQuery(userCardElement).data('user-card', username ?? '');
userCardElement.addEventListener('click', (e) => {
if (!userCardElement.getAttribute('data-user-card')) {
e.preventDefault();
e.stopPropagation();
}
});
}
// Reload avatar image if failed.
const avatarElement = replyContainer.querySelector('.avatar');
avatarElement.reloadAttempt = 0;
avatarElement.addEventListener('error', async () => {
if (!avatarElement.src || avatarElement.src === EMPTY_IMG) {
return;
}
avatarElement.reloadAttempt += 1;
if (avatarElement.reloadAttempt > FETCH_MAX_RETRIES) {
return;
}
await sleep(1000 * EXP_BACKOFF_START * EXP_BACKOFF_BASE ** (avatarElement.reloadAttempt - 1));
// eslint-disable-next-line no-self-assign
avatarElement.src = avatarElement.src;
});
replyContainer.style.visibility = '';
loadingStateNode.textContent = `加载中 (${replyId} / ${maxReplyId}) ...`;
}
loadingStateNode.textContent = '加载完成';
});
await updateView(INITIAL_REPLY_ID);
viewerInitialized = true;
};
const observer = new MutationObserver(async (mutationsList) => {
for (const mutation of mutationsList) {
if (mutation.type === 'childList') {
for (const el of mutation.addedNodes) {
if (el.classList?.contains(APPEND_VIEWER_TARGET_CLASS)) {
// eslint-disable-next-line no-await-in-loop -- addViewer should ideally only happen once
await addViewer(el);
}
}
} else if (mutation.type === 'attributes') {
if (!mutation.oldValue?.match(new RegExp(`(?:^|\\s)${escapeRegExpOutsideCharacterClass(APPEND_VIEWER_TARGET_CLASS)}(?:\\s|$)`, 'u')) &&
mutation.target.classList?.contains(APPEND_VIEWER_TARGET_CLASS)) {
// eslint-disable-next-line no-await-in-loop -- addViewer should ideally only happen once
await addViewer(mutation.target);
}
}
}
});
observer.observe(document.documentElement, {
subtree: true,
childList: true,
attributeFilter: ['class'],
attributeOldValue: true,
});
await addViewer(document.getElementsByClassName(APPEND_VIEWER_TARGET_CLASS)[0]);
})();