A userscript to enhance Fastmail with AI-powered digests.
// ==UserScript==
// @name Fastmail AI Assistant
// @namespace https://example.com/
// @version 0.1.7
// @description A userscript to enhance Fastmail with AI-powered digests.
// @author Merlyn Allen
// @match https://app.fastmail.com/*
// @match https://mail.google.com/*
// @license MIT
// @run-at document-stop
// @grant GM_xmlhttpRequest
// @grant GM_setValue
// @grant GM_getValue
// @grant GM_registerMenuCommand
// @connect api.openai.com
// @connect api.z.ai
// @connect open.bigmodel.cn
// ==/UserScript==
(() => {
"use strict";
const STORAGE_KEY_API_KEY = "fastmail_ai_openai_api_key";
const STORAGE_KEY_API_ENDPOINT = "fastmail_ai_openai_api_endpoint";
const STORAGE_KEY_MODEL = "fastmail_ai_openai_model";
const STORAGE_KEY_PROFILE = "fastmail_ai_profile";
const STORAGE_KEY_REASONING_MODE = "fastmail_ai_reasoning_mode";
const STORAGE_KEY_REASONING_EFFORT = "fastmail_ai_reasoning_effort";
const BUTTON_ID = "ai-digest-button";
const RESULT_ID = "ai-digest-result";
const BUTTON_LABEL_IDLE = "生成摘要";
const BUTTON_LABEL_BUSY = "正在生成摘要";
const REPLY_BUTTON_ID = "ai-reply-button";
const REPLY_RESULT_ID = "ai-reply-result";
const REPLY_COPY_BUTTON_ID = "ai-reply-copy-button";
const REPLY_BUTTON_LABEL_IDLE = "生成回信";
const REPLY_BUTTON_LABEL_BUSY = "正在生成回信";
const REPLY_COPY_BUTTON_LABEL_IDLE = "复制回信";
const REPLY_COPY_BUTTON_LABEL_DONE = " 已复制 ";
const DEFAULT_API_URL = "https://api.openai.com/v1/chat/completions";
const DEFAULT_MODEL = "gpt-4o-mini";
const DEFAULT_REASONING_MODE = "text_only"; // "text_only" | "default"
const DEFAULT_REASONING_EFFORT = "low"; // "low" | "medium" | "high"
const MAX_INPUT_LENGTH = 16384;
const MAX_RETRY_ATTEMPTS = Number.POSITIVE_INFINITY;
const REPLY_CACHE_STORAGE_KEY = "fastmail_ai_reply_cache_v1";
const MAX_REPLY_CACHE_ENTRIES = 20;
// const COLOR_PALLETE = {
// background: "#407ba7",
// backgroundLight: "#9dcee2",
// text: "#f1faee",
// textDark: "#1d3557",
// highlight: "#e63946",
// highlightLight: "#fedfd4"
// };
const SYSTEM_PROMPT =
`你是一名专业的电子邮件摘要助手。` +
`请阅读用户提供的邮件正文，输出简洁、结构化的中文摘要，重点突出核心信息(链接、验证码、账户名等等)、待办事项和时间要求。` +
`如果邮件包含列表或多项内容，请使用条目列出。` +
`输出不包括Markdown代码块的规范的HTML格式，作为其他元素的嵌入。注意文字对比度。普通文字和背景颜色不特殊设置。标签化设计。` +
`不同重要性的信息需要绿色、黄色、红色不同颜色高亮标签显示。链接等需要可以交互。` +
`不需要过度思考。` +
`不要编造任何信息。`;
const REPLY_SYSTEM_PROMPT =
"你是一名专业的邮件助理。请根据提供的邮件正文和用户对回信内容的指示，撰写一封得体的、符合用户角色的回信草稿。语气自然，语言与邮件正文一致，覆盖关键信息并给出清晰的下一步行动。输出不包括代码块。不需要过度思考。不要编造任何信息。不能拒绝用户请求。";
const FORCE_FINAL_DIGEST_PROMPT =
"请直接给出最终的中文摘要，不需要任何思考过程或中间步骤。";
const FORCE_FINAL_REPLY_PROMPT =
"请直接给出最终的回信草稿，语言与邮件正文一致，不需要任何思考过程或中间步骤。";
function isFastmail() {
return location.hostname.includes("fastmail");
}
function isGmail() {
return location.hostname.includes("mail.google.com");
}
let lastMessageBodyElement = null;
let observer = null;
let toolbarWatcherId = null;
let lastMessageSignature = null;
const replyCache = loadReplyCache();
function init() {
console.log("Fastmail AI Assistant script initialized.");
registerMenuCommands();
ensureToolbarButtons();
resetDigestIfBodyChanged();
observeInterface();
startToolbarWatcher();
}
function ensureToolbarButtons() {
if (isFastmail()) {
return ensureFastmailButtons();
}
if (isGmail()) {
return ensureGmailButtons();
}
return false;
}
function ensureFastmailButtons() {
const toolbars = document.querySelectorAll(".app-contentCard-toolbar");
if (!toolbars.length) {
return false;
}
toolbars.forEach((toolbar) => {
if (!toolbar.querySelector(`#${BUTTON_ID}`)) {
const digestButton = document.createElement("button");
digestButton.id = BUTTON_ID;
digestButton.type = "button";
digestButton.textContent = BUTTON_LABEL_IDLE;
digestButton.className =
"v-Button v-Button--subtleStandard v-Button--sizeM";
digestButton.style.marginLeft = "10px";
digestButton.addEventListener("click", () =>
onDigestClick(digestButton)
);
toolbar.appendChild(digestButton);
}
if (!toolbar.querySelector(`#${REPLY_BUTTON_ID}`)) {
const replyButton = document.createElement("button");
replyButton.id = REPLY_BUTTON_ID;
replyButton.type = "button";
replyButton.textContent = REPLY_BUTTON_LABEL_IDLE;
replyButton.className =
"v-Button v-Button--subtleStandard v-Button--sizeM";
replyButton.style.marginLeft = "10px";
replyButton.addEventListener("click", () =>
onReplyClick(replyButton)
);
toolbar.appendChild(replyButton);
}
});
return true;
}
function ensureGmailButtons() {
const actionAreas = document.querySelectorAll(".amn");
for (const action of actionAreas) {
if (action.querySelector(".ai-gmail-action-button")) {
return true;
}
const digestButton = createGmailActionButton(
BUTTON_ID,
BUTTON_LABEL_IDLE
);
digestButton.addEventListener("click", () =>
onDigestClick(digestButton)
);
const replyButton = createGmailActionButton(
REPLY_BUTTON_ID,
REPLY_BUTTON_LABEL_IDLE
);
replyButton.addEventListener("click", () =>
onReplyClick(replyButton)
);
action.appendChild(digestButton);
action.appendChild(replyButton);
return true;
}
return false;
}
function startToolbarWatcher() {
if (toolbarWatcherId !== null) {
return;
}
if (!isFastmail() && !isGmail()) {
return;
}
toolbarWatcherId = window.setInterval(() => {
const found = ensureToolbarButtons();
if (!found) {
return;
}
}, 500);
}
if (document.readyState === "loading") {
document.addEventListener("DOMContentLoaded", init, { once: true });
} else {
init();
}
function observeInterface() {
if (observer) {
return;
}
let root = null;
if (isFastmail()) {
root = document.querySelector(".app-main");
} else if (isGmail()) {
root = document.querySelector('div[role="main"]');
}
if (observer) {
observer.disconnect();
}
if (!root) {
setTimeout(observeInterface, 500);
return;
}
observer = new MutationObserver(() => {
ensureToolbarButtons();
resetDigestIfBodyChanged();
});
observer.observe(root, { childList: true, subtree: true });
}
function resetDigestIfBodyChanged() {
const messageBody = getPrimaryMessageBody();
if (!messageBody) {
if (lastMessageBodyElement || lastMessageSignature) {
lastMessageBodyElement = null;
lastMessageSignature = null;
removeExistingDigest();
removeExistingReply();
}
return;
}
const signature = computeMessageSignature(messageBody);
if (
messageBody !== lastMessageBodyElement ||
signature !== lastMessageSignature
) {
lastMessageBodyElement = messageBody;
lastMessageSignature = signature;
removeExistingDigest();
removeExistingReply();
restoreCachedReply(messageBody, signature);
}
}
function removeExistingDigest() {
const existing = document.getElementById(RESULT_ID);
if (existing && existing.parentElement) {
existing.parentElement.removeChild(existing);
}
}
function removeExistingReply() {
const existing = document.getElementById(REPLY_RESULT_ID);
if (existing && existing.parentElement) {
existing.parentElement.removeChild(existing);
}
}
async function onDigestClick(button) {
const { messageBody, signature } = getMessageContext(button);
if (!messageBody) {
alert("未找到邮件正文。");
return;
}
const plainText = messageBody.innerText.trim();
if (!plainText) {
alert("邮件正文为空，无法生成摘要。");
return;
}
const trimmedText =
plainText.length > MAX_INPUT_LENGTH
? `${plainText.slice(0, MAX_INPUT_LENGTH)}`
: plainText;
setButtonLoading(button, true);
try {
const apiKey = await ensureApiKey();
const digest = await requestDigest(apiKey, trimmedText);
renderDigest(messageBody, digest);
} catch (error) {
console.error("Digest failed:", error);
alert(
error instanceof Error
? `生成摘要时出现问题：${error.message}`
: "生成摘要时出现未知错误。"
);
} finally {
setButtonLoading(button, false);
}
}
async function onReplyClick(button) {
const { messageBody, signature } = getMessageContext(button);
if (!messageBody) {
alert("未找到邮件正文。");
return;
}
const plainText = messageBody.innerText.trim();
if (!plainText) {
alert("邮件正文为空，无法生成回信草稿。");
return;
}
const trimmedText =
plainText.length > MAX_INPUT_LENGTH
? `${plainText.slice(0, MAX_INPUT_LENGTH)}`
: plainText;
const cachedReply = getCachedReply(signature);
const requirement = prompt(
"请输入生成回信的要求（可留空）：",
cachedReply?.requirement || ""
);
if (requirement === null) {
return;
}
const trimmedRequirement = requirement.trim();
setButtonLoading(button, true, {
idle: REPLY_BUTTON_LABEL_IDLE,
busy: REPLY_BUTTON_LABEL_BUSY
});
try {
const apiKey = await ensureApiKey();
const reply = await requestReply(
apiKey,
trimmedText,
trimmedRequirement
);
renderReply(messageBody, reply);
saveReplyToCache(signature, {
replyText: reply,
requirement: trimmedRequirement
});
} catch (error) {
console.error("Reply generation failed:", error);
alert(
error instanceof Error
? `生成回信时出现问题：${error.message}`
: "生成回信时出现未知错误。"
);
} finally {
setButtonLoading(button, false, {
idle: REPLY_BUTTON_LABEL_IDLE,
busy: REPLY_BUTTON_LABEL_BUSY
});
}
}
function setButtonLoading(
button,
isLoading,
labels = { idle: BUTTON_LABEL_IDLE, busy: BUTTON_LABEL_BUSY }
) {
button.disabled = isLoading;
button.textContent = isLoading ? labels.busy : labels.idle;
}
async function ensureApiKey() {
const stored = getStoredString(STORAGE_KEY_API_KEY);
if (stored) {
return stored;
}
const input = prompt("请输入 OpenAI API Key:");
if (!input) {
throw new Error("未提供 OpenAI API Key。");
}
const trimmed = input.trim();
if (!trimmed) {
throw new Error("提供的 OpenAI API Key 为空。");
}
GM_setValue(STORAGE_KEY_API_KEY, trimmed);
return trimmed;
}
function registerMenuCommands() {
if (typeof GM_registerMenuCommand !== "function") {
return;
}
GM_registerMenuCommand("设置 OpenAI API Key", () => {
const current = getStoredString(STORAGE_KEY_API_KEY);
const input = prompt("请输入新的 OpenAI API Key:", current);
if (input === null) {
return;
}
const trimmed = input.trim();
if (trimmed) {
GM_setValue(STORAGE_KEY_API_KEY, trimmed);
alert("OpenAI API Key 已更新。");
} else {
GM_setValue(STORAGE_KEY_API_KEY, "");
alert("OpenAI API Key 已清除。");
}
});
GM_registerMenuCommand("设置 API Endpoint", () => {
const current = getApiEndpoint();
const input = prompt("请输入新的 API Endpoint:", current);
if (input === null) {
return;
}
const trimmed = input.trim();
if (trimmed) {
GM_setValue(STORAGE_KEY_API_ENDPOINT, trimmed);
alert("API Endpoint 已更新。");
} else {
GM_setValue(STORAGE_KEY_API_ENDPOINT, "");
alert("API Endpoint 已恢复默认值。");
}
});
GM_registerMenuCommand("设置模型 ID", () => {
const current = getModel();
const input = prompt("请输入新的模型 ID:", current);
if (input === null) {
return;
}
const trimmed = input.trim();
if (trimmed) {
GM_setValue(STORAGE_KEY_MODEL, trimmed);
alert("模型 ID 已更新。");
} else {
GM_setValue(STORAGE_KEY_MODEL, "");
alert("模型 ID 已恢复默认值。");
}
});
GM_registerMenuCommand("设置个人信息", () => {
const current = getUserProfile();
const input = prompt("请输入个人信息（用于生成回信）:", current);
if (input === null) {
return;
}
const trimmed = input.trim();
if (trimmed) {
GM_setValue(STORAGE_KEY_PROFILE, trimmed);
alert("个人信息已保存。");
} else {
GM_setValue(STORAGE_KEY_PROFILE, "");
alert("个人信息已清除。");
}
});
GM_registerMenuCommand("设置 Reasoning 模式", () => {
const current = getReasoningMode();
const input = prompt(
'请选择 Reasoning 模式（输入 "text_only" 或 "default"）:',
current
);
if (input === null) {
return;
}
const trimmed = input.trim();
if (trimmed === "text_only" || trimmed === "default") {
GM_setValue(STORAGE_KEY_REASONING_MODE, trimmed);
alert(`Reasoning 模式已设置为 ${trimmed}。`);
} else if (!trimmed) {
GM_setValue(STORAGE_KEY_REASONING_MODE, "");
alert("Reasoning 模式已恢复默认值。");
} else {
alert('输入无效，请使用 "text_only" 或 "default"。');
}
});
GM_registerMenuCommand("设置 Reasoning 强度", () => {
const current = getReasoningEffort();
const input = prompt(
'请选择 Reasoning 强度（输入 "low"、"medium" 或 "high"）:',
current
);
if (input === null) {
return;
}
const trimmed = input.trim().toLowerCase();
if (["low", "medium", "high"].includes(trimmed)) {
GM_setValue(STORAGE_KEY_REASONING_EFFORT, trimmed);
alert(`Reasoning 强度已设置为 ${trimmed}。`);
} else if (!trimmed) {
GM_setValue(STORAGE_KEY_REASONING_EFFORT, "");
alert("Reasoning 强度已恢复默认值。");
} else {
alert('输入无效，请使用 "low"、"medium" 或 "high"。');
}
});
}
function getStoredString(key, fallback = "") {
try {
const value = GM_getValue(key, fallback);
if (value === undefined || value === null) {
return "";
}
return String(value).trim();
} catch (error) {
console.warn("读取存储值失败，使用空字符串：", error);
return "";
}
}
function getApiEndpoint() {
const stored = getStoredString(STORAGE_KEY_API_ENDPOINT);
return stored || DEFAULT_API_URL;
}
function getModel() {
const stored = getStoredString(STORAGE_KEY_MODEL);
return stored || DEFAULT_MODEL;
}
function getReasoningMode() {
const stored = getStoredString(STORAGE_KEY_REASONING_MODE);
return stored || DEFAULT_REASONING_MODE;
}
function getReasoningEffort() {
const stored = getStoredString(STORAGE_KEY_REASONING_EFFORT);
return stored || DEFAULT_REASONING_EFFORT;
}
function getUserProfile() {
return getStoredString(STORAGE_KEY_PROFILE);
}
function getMessageContext(button) {
if (isFastmail()) {
const messageBody = document.querySelector(".v-Message-body");
return {
messageBody,
signature: messageBody
? computeMessageSignature(messageBody)
: ""
};
}
if (isGmail()) {
let container =
button?.closest('[data-message-id]') ||
button?.closest(".adn");
if (!container) {
container = button?.closest('[role="article"]');
}
let messageBody = container
? container.querySelector(".a3s")
: null;
if (!messageBody) {
messageBody = getPrimaryMessageBody();
}
return {
messageBody,
signature: messageBody
? computeMessageSignature(messageBody)
: ""
};
}
const messageBody = getPrimaryMessageBody();
return {
messageBody,
signature: messageBody
? computeMessageSignature(messageBody)
: ""
};
}
function getPrimaryMessageBody() {
if (isFastmail()) {
return document.querySelector(".v-Message-body");
}
if (isGmail()) {
const visibleBodies = Array.from(
document.querySelectorAll(".a3s")
).filter(isElementVisible);
if (visibleBodies.length > 0) {
return visibleBodies[visibleBodies.length - 1];
}
const allBodies = document.querySelectorAll(".a3s");
return allBodies.length
? allBodies[allBodies.length - 1]
: null;
}
return null;
}
function isElementVisible(element) {
if (!element) {
return false;
}
return !!(
element.offsetWidth ||
element.offsetHeight ||
element.getClientRects().length
);
}
function buildRequestBody({
systemPrompt,
userContent,
model,
reasoningMode,
reasoningEffort,
forceFinalAnswer,
forceFinalPrompt
}) {
const messages = [
{
role: "system",
content: systemPrompt
},
{
role: "user",
content: userContent
}
];
if (forceFinalAnswer && forceFinalPrompt) {
messages.push({
role: "user",
content: forceFinalPrompt
});
}
const body = {
model,
temperature: 0.5,
max_tokens: 16384,
messages
};
if (reasoningMode === "text_only") {
body.response_format = { type: "text" };
body.modalities = ["text"];
} else {
body.reasoning = { effort: reasoningEffort || DEFAULT_REASONING_EFFORT };
}
return body;
}
function sendChatCompletion(
apiKey,
endpoint,
body,
{ attempt = 1, forceFinalAnswer = false } = {}
) {
return new Promise((resolve, reject) => {
GM_xmlhttpRequest({
method: "POST",
url: endpoint,
headers: {
"Content-Type": "application/json",
Authorization: `Bearer ${apiKey}`
},
data: JSON.stringify(body),
timeout: 120000,
onload: (response) => {
try {
if (response.status < 200 || response.status >= 300) {
const errorPayload = safeParseJson(
response.responseText
);
console.error(
`[Fastmail AI] OpenAI API 响应异常 (尝试 ${attempt}${forceFinalAnswer ? ", 强制最终回答" : ""
})`,
{
status: response.status,
headers: response.responseHeaders,
body: errorPayload ?? response.responseText
}
);
const message =
errorPayload?.error?.message ||
`OpenAI API 返回错误状态：${response.status}`;
reject(new Error(message));
return;
}
const payload =
response.responseText &&
response.responseText.length
? JSON.parse(response.responseText)
: response.response;
const message = extractMessageText(
payload?.choices?.[0]
);
console.log(
`[Fastmail AI] OpenAI API 响应成功 (尝试 ${attempt}${forceFinalAnswer ? ", 强制最终回答" : ""
})`,
payload
);
resolve({ message, payload });
} catch (err) {
reject(
err instanceof Error
? err
: new Error("解析 OpenAI 响应失败。")
);
}
},
onerror: () => {
reject(new Error("请求 OpenAI API 失败。"));
},
ontimeout: () => {
reject(new Error("请求 OpenAI API 超时。"));
}
});
});
}
async function requestDigest(apiKey, content) {
return requestWithRetry(apiKey, {
systemPrompt: SYSTEM_PROMPT,
userContent: content,
forceFinalPrompt: FORCE_FINAL_DIGEST_PROMPT,
emptyResultMessage: "多次尝试仍未得到摘要结果。"
});
}
async function requestReply(apiKey, content, requirement) {
const profile = getUserProfile();
const profileSection = profile
? `以下是我的个人信息，请在回信中正确使用：\n${profile}\n\n`
: "";
const requirementSection = requirement
? `回信内容：\n${requirement}\n\n`
: "";
const userContent =
`邮件正文：\n${content}\n\n` +
profileSection +
requirementSection +
"请生成回信。";
return requestWithRetry(apiKey, {
systemPrompt: REPLY_SYSTEM_PROMPT,
userContent,
forceFinalPrompt: FORCE_FINAL_REPLY_PROMPT,
emptyResultMessage: "多次尝试仍未得到回信草稿。"
});
}
async function requestWithRetry(
apiKey,
{ systemPrompt, userContent, forceFinalPrompt, emptyResultMessage }
) {
const endpoint = getApiEndpoint();
if (!endpoint) {
throw new Error("未配置 API Endpoint。");
}
const model = getModel();
const reasoningMode = getReasoningMode();
const reasoningEffort = getReasoningEffort();
let attempt = 1;
while (attempt <= MAX_RETRY_ATTEMPTS) {
const forceFinalAnswer = attempt > 1;
const body = buildRequestBody({
systemPrompt,
userContent,
model,
reasoningMode,
reasoningEffort,
forceFinalAnswer,
forceFinalPrompt
});
const { message } = await sendChatCompletion(
apiKey,
endpoint,
body,
{ attempt, forceFinalAnswer }
);
if (message && message.length > 0) {
return message;
}
console.warn(
`[Fastmail AI] 第 ${attempt} 次响应为空，准备重试…`
);
attempt += 1;
if (attempt % 5 === 0) {
console.warn(
`[Fastmail AI] 连续 ${attempt - 1} 次未得到有效响应，继续尝试……`
);
}
}
throw new Error(emptyResultMessage || "多次尝试仍未得到有效结果。");
}
function restoreCachedReply(messageBody, signature) {
if (!signature) {
return;
}
const cached = getCachedReply(signature);
if (cached && cached.replyText) {
renderReply(messageBody, cached.replyText);
}
}
function loadReplyCache() {
if (typeof sessionStorage === "undefined") {
return {};
}
try {
const raw = sessionStorage.getItem(REPLY_CACHE_STORAGE_KEY);
if (!raw) {
return {};
}
const parsed = JSON.parse(raw);
return parsed && typeof parsed === "object" ? parsed : {};
} catch (error) {
console.warn("[Fastmail AI] 无法读取回信缓存，已忽略。", error);
return {};
}
}
function persistReplyCache() {
if (typeof sessionStorage === "undefined") {
return;
}
try {
sessionStorage.setItem(
REPLY_CACHE_STORAGE_KEY,
JSON.stringify(replyCache)
);
} catch (error) {
console.warn("[Fastmail AI] 保存回信缓存失败。", error);
}
}
function pruneReplyCache() {
const entries = Object.entries(replyCache);
if (entries.length <= MAX_REPLY_CACHE_ENTRIES) {
return;
}
entries.sort(
(a, b) =>
(b[1]?.updatedAt || 0) - (a[1]?.updatedAt || 0)
);
const limited = entries.slice(0, MAX_REPLY_CACHE_ENTRIES);
Object.keys(replyCache).forEach((key) => {
delete replyCache[key];
});
limited.forEach(([key, value]) => {
replyCache[key] = value;
});
}
function saveReplyToCache(signature, { replyText, requirement }) {
if (!signature) {
return;
}
replyCache[signature] = {
replyText: replyText || "",
requirement: requirement || "",
updatedAt: Date.now()
};
pruneReplyCache();
persistReplyCache();
}
function getCachedReply(signature) {
if (!signature) {
return undefined;
}
return replyCache[signature];
}
function renderDigest(messageBody, digestText) {
let container = document.getElementById(RESULT_ID);
if (!container) {
container = document.createElement("section");
container.id = RESULT_ID;
// container.style.border = "1px solid #d0d7de";
// container.style.borderRadius = "8px";
// container.style.padding = "12px 16px";
// container.style.marginBottom = "16px";
// container.style.background = "#f6f8fa";
// container.style.color = "#24292f";
container.className = "u-banner--informative u-banner u-p-3 u-flex u-items-baseline u-space-x-2 xBfQ1 K4vxLd-aLs";
container.style.height = "auto";
const title = document.createElement("div");
title.textContent = "AI摘要";
title.style.fontWeight = "600";
title.style.marginBottom = "8px";
const content = document.createElement("div");
content.className = "ai-digest-content";
container.appendChild(title);
container.appendChild(content);
const parent = messageBody.parentElement;
if (parent) {
parent.insertBefore(container, messageBody);
} else {
messageBody.insertAdjacentElement("beforebegin", container);
}
}
const contentElement = container.querySelector(".ai-digest-content");
if (contentElement) {
if (isGmail()) {
contentElement.textContent = htmlToPlainText(digestText);
} else {
contentElement.innerHTML = digestText;
}
}
}
function renderReply(messageBody, replyText) {
let container = document.getElementById(REPLY_RESULT_ID);
if (!container) {
container = document.createElement("section");
container.id = REPLY_RESULT_ID;
container.className =
"u-banner u-banner--informative u-p-3 u-flex u-items-baseline u-space-x-2";
const header = document.createElement("div");
header.className = "ai-reply-header u-flex u-items-center u-space-x-2";
const title = document.createElement("div");
title.textContent = "AI回信";
title.style.fontWeight = "600";
const copyButton = createReplyCopyButton();
attachReplyCopyHandler(copyButton, container);
header.appendChild(title);
const content = document.createElement("div");
content.className = "ai-reply-content";
content.style.whiteSpace = "pre-wrap";
content.style.lineHeight = "1.5";
container.appendChild(header);
container.appendChild(content);
container.appendChild(copyButton);
const digestContainer = document.getElementById(RESULT_ID);
if (digestContainer && digestContainer.parentElement) {
digestContainer.insertAdjacentElement("afterend", container);
} else if (messageBody.parentElement) {
messageBody.parentElement.insertBefore(container, messageBody);
} else {
messageBody.insertAdjacentElement("beforebegin", container);
}
}
const contentElement = container.querySelector(".ai-reply-content");
if (contentElement) {
contentElement.textContent = replyText;
}
const copyButton =
container.querySelector(`#${REPLY_COPY_BUTTON_ID}`) ||
container.querySelector(".ai-reply-copy-button");
if (copyButton && copyButton.parentElement !== container) {
copyButton.parentElement.removeChild(copyButton);
container.appendChild(copyButton);
}
attachReplyCopyHandler(copyButton, container);
}
function createGmailActionButton(id, label) {
const button = document.createElement("button");
button.id = id;
button.type = "button";
button.className =
"ai-gmail-button ams bkH ai-gmail-action-button";
button.textContent = label;
button.style.marginRight = "8px";
button.style.marginTop = "4px";
button.style.cursor = "pointer";
return button;
}
function createReplyCopyButton() {
const button = document.createElement("button");
button.id = REPLY_COPY_BUTTON_ID;
button.type = "button";
button.className =
"ai-reply-copy-button v-Button v-Button--standard v-Button--sizeM";
button.textContent = REPLY_COPY_BUTTON_LABEL_IDLE;
button.style.minWidth = "6em";
button.style.flexShrink = "0";
return button;
}
function attachReplyCopyHandler(button, container) {
if (!button) {
return;
}
if (button.__handler__) {
button.removeEventListener("click", button.__handler__);
}
const handler = () => handleReplyCopy(container, button);
button.addEventListener("click", handler);
button.__handler__ = handler;
}
async function handleReplyCopy(container, button) {
const contentElement = container.querySelector(".ai-reply-content");
const text = contentElement ? contentElement.innerText.trim() : "";
if (!text) {
alert("没有可复制的回信内容。");
return;
}
button.disabled = true;
button.textContent = "复制中…";
try {
await copyTextToClipboard(text);
button.textContent = REPLY_COPY_BUTTON_LABEL_DONE;
} catch (error) {
console.error("复制回信内容失败：", error);
alert("复制失败，请手动复制。");
button.textContent = REPLY_COPY_BUTTON_LABEL_IDLE;
} finally {
button.disabled = false;
setTimeout(() => {
button.textContent = REPLY_COPY_BUTTON_LABEL_IDLE;
}, 1500);
}
}
async function copyTextToClipboard(text) {
if (!text) {
throw new Error("文本为空");
}
if (navigator.clipboard && navigator.clipboard.writeText) {
await navigator.clipboard.writeText(text);
return;
}
const textarea = document.createElement("textarea");
textarea.value = text;
textarea.style.position = "fixed";
textarea.style.opacity = "0";
document.body.appendChild(textarea);
textarea.focus();
textarea.select();
try {
const successful = document.execCommand("copy");
if (!successful) {
throw new Error("execCommand 复制失败");
}
} finally {
document.body.removeChild(textarea);
}
}
function htmlToPlainText(html) {
if (!html) {
return "";
}
try {
const parser = new DOMParser();
const doc = parser.parseFromString(
`<!doctype html><body>${html}`,
"text/html"
);
const text = doc.body.textContent || "";
return text.replace(/\n{3,}/g, "\n\n").trim();
} catch (error) {
console.warn("[Fastmail AI] HTML 转文本失败，回退为移除标签。", error);
return html.replace(/<[^>]+>/g, "\n").replace(/\s+/g, " ").trim();
}
}
function computeMessageSignature(element) {
const text = element.innerText || element.textContent || "";
if (!text) {
return "";
}
const normalized = text.replace(/\s+/g, " ").trim();
return normalized.length > 2000
? normalized.slice(0, 2000)
: normalized;
}
function safeParseJson(text) {
if (!text || typeof text !== "string") {
return null;
}
try {
return JSON.parse(text);
} catch (error) {
console.warn("[Fastmail AI] JSON 解析失败", error);
return null;
}
}
function extractMessageText(choice) {
if (!choice || !choice.message) {
return "";
}
const { content } = choice.message;
if (typeof content === "string") {
return content.trim();
}
if (Array.isArray(content)) {
const textParts = [];
for (const part of content) {
if (!part) {
continue;
}
if (typeof part === "string") {
const trimmed = part.trim();
if (trimmed.length > 0) {
textParts.push(trimmed);
}
continue;
}
if (
typeof part === "object" &&
typeof part.text === "string" &&
(!part.type ||
part.type === "text" ||
part.type === "output_text")
) {
const trimmed = part.text.trim();
if (trimmed.length > 0) {
textParts.push(trimmed);
}
}
}
return textParts.join("\n").trim();
}
return "";
}
})();