// ==UserScript==
// @name         B站全部取消关注（自动续跑）
// @namespace    codex.local
// @version      1.0.0
// @description  使用B站关注页原生按钮分批取消关注，自动刷新续跑，遇到手机号验证自动暂停。
// @match        https://space.bilibili.com/*/relation/follow*
// @grant        none
// @run-at       document-idle
// ==/UserScript==

(() => {
  "use strict";

  if (window.__CODEX_BILI_UNFOLLOW_ALL__) return;
  window.__CODEX_BILI_UNFOLLOW_ALL__ = true;

  const STORAGE_KEY = "codex:bilibili-unfollow-all:v1";
  const MIN_DELAY_MS = 600;
  const MAX_DELAY_MS = 900;
  const PAGE_SIZE = 24;

  const sleep = ms => new Promise(resolve => setTimeout(resolve, ms));

  const readState = () => {
    try {
      return {
        running: false,
        success: 0,
        startedAt: null,
        ...JSON.parse(localStorage.getItem(STORAGE_KEY) || "{}"),
      };
    } catch {
      return { running: false, success: 0, startedAt: null };
    }
  };

  const writeState = patch => {
    const next = { ...readState(), ...patch };
    localStorage.setItem(STORAGE_KEY, JSON.stringify(next));
    return next;
  };

  const isRunning = () => readState().running === true;

  const currentMid = () => {
    const match = location.pathname.match(/^\/(\d+)\/relation\/follow/);
    return match?.[1] || null;
  };

  const getFollowButtons = () =>
    [...document.querySelectorAll(".follow-btn__trigger.gray")].filter(el =>
      (el.textContent || "").includes("已关注"),
    );

  const isVisible = el =>
    Boolean(el && (el.offsetWidth || el.offsetHeight || el.getClientRects().length));

  const hasPhoneVerification = () =>
    [...document.querySelectorAll("body *")].some(
      el =>
        isVisible(el) &&
        (el.textContent || "").trim() === "请输入您绑定的手机号码",
    );

  const pressEscape = () => {
    for (const type of ["keydown", "keyup"]) {
      document.dispatchEvent(
        new KeyboardEvent(type, {
          key: "Escape",
          code: "Escape",
          keyCode: 27,
          which: 27,
          bubbles: true,
        }),
      );
    }
  };

  const identifyAccount = button => {
    let node = button;

    for (let i = 0; i < 8 && node; i++, node = node.parentElement) {
      const link = [...node.querySelectorAll('a[href*="follow.user_card.click"]')]
        .find(el => (el.textContent || "").trim());

      if (!link) continue;

      const mid = (link.getAttribute("href") || "").match(
        /space\.bilibili\.com\/(\d+)/,
      )?.[1];

      return {
        mid: mid || "unknown",
        name: (link.textContent || "").trim() || "未知账号",
      };
    }

    return { mid: "unknown", name: "未知账号" };
  };

  const waitForButtonDecrease = async (before, timeoutMs = 1800) => {
    const deadline = Date.now() + timeoutMs;

    while (Date.now() < deadline) {
      await sleep(100);
      const count = getFollowButtons().length;

      if (count === before - 1) return count;
      if (hasPhoneVerification()) return count;
    }

    return getFollowButtons().length;
  };

  const fetchLiveTotal = async () => {
    const mid = currentMid();
    if (!mid) return null;

    const params = new URLSearchParams({
      order: "desc",
      order_type: "",
      vmid: mid,
      pn: "1",
      ps: "1",
      gaia_source: "main_web",
      web_location: "333.1387",
    });

    try {
      const response = await fetch(
        `https://api.bilibili.com/x/relation/followings?${params}`,
        { credentials: "include" },
      );
      const result = await response.json();
      return result.code === 0 ? Number(result.data?.total ?? 0) : null;
    } catch {
      return null;
    }
  };

  const waitForPageReady = async (timeoutMs = 30000) => {
    const deadline = Date.now() + timeoutMs;

    while (Date.now() < deadline && isRunning()) {
      if (hasPhoneVerification()) return "verification";
      if (getFollowButtons().length > 0) return "ready";

      const total = await fetchLiveTotal();
      if (total === 0) return "complete";

      await sleep(500);
    }

    return "timeout";
  };

  const panel = document.createElement("div");
  panel.id = "codex-bili-unfollow-panel";
  panel.style.cssText = [
    "position:fixed",
    "right:20px",
    "bottom:20px",
    "z-index:2147483647",
    "width:280px",
    "padding:14px",
    "border-radius:10px",
    "background:rgba(25,25,25,.94)",
    "color:#fff",
    "font:13px/1.6 -apple-system,BlinkMacSystemFont,Segoe UI,sans-serif",
    "box-shadow:0 8px 28px rgba(0,0,0,.35)",
  ].join(";");

  panel.innerHTML = `
    <div style="font-weight:700;font-size:15px;margin-bottom:8px">B站全部取消关注</div>
    <div id="codex-bili-unfollow-status" style="min-height:42px;margin-bottom:10px">等待操作</div>
    <div style="display:flex;gap:8px">
      <button id="codex-bili-unfollow-start" style="flex:1;padding:7px;border:0;border-radius:6px;background:#00aeec;color:#fff;cursor:pointer">开始</button>
      <button id="codex-bili-unfollow-stop" style="flex:1;padding:7px;border:0;border-radius:6px;background:#555;color:#fff;cursor:pointer">停止</button>
    </div>
  `;

  document.body.appendChild(panel);

  const statusElement = panel.querySelector("#codex-bili-unfollow-status");
  const startButton = panel.querySelector("#codex-bili-unfollow-start");
  const stopButton = panel.querySelector("#codex-bili-unfollow-stop");

  const setStatus = text => {
    statusElement.textContent = text;
    console.log(`[B站取消关注] ${text}`);
  };

  const pauseForVerification = async () => {
    setStatus("B站要求手机号验证，请手动完成；验证消失后会自动继续。请勿关闭此页面。");

    while (isRunning() && hasPhoneVerification()) {
      await sleep(1500);
    }

    if (isRunning()) {
      setStatus("验证已解除，准备继续……");
      await sleep(1000);
    }
  };

  const unfollowOne = async () => {
    pressEscape();
    await sleep(150);

    let buttons = getFollowButtons();
    const before = buttons.length;

    if (before === 0) return { status: "empty" };

    const account = identifyAccount(buttons[0]);
    buttons[0].click();

    let after = await waitForButtonDecrease(before);
    pressEscape();

    if (hasPhoneVerification()) {
      return { status: "verification", account };
    }

    // 偶尔第一次点击只会关闭上一条遗留的菜单，确认数量没变化后补点一次。
    if (after !== before - 1) {
      await sleep(250);
      pressEscape();
      buttons = getFollowButtons();

      if (buttons.length === before) {
        buttons[0].click();
        after = await waitForButtonDecrease(before);
        pressEscape();
      }
    }

    if (hasPhoneVerification()) {
      return { status: "verification", account };
    }

    if (after !== before - 1) {
      return { status: "failed", account, before, after };
    }

    return { status: "success", account };
  };

  const run = async () => {
    if (!isRunning()) return;

    const ready = await waitForPageReady();

    if (ready === "verification") {
      await pauseForVerification();
      if (isRunning()) run();
      return;
    }

    if (ready === "complete") {
      writeState({ running: false });
      setStatus(`完成：当前关注数为 0。本次确认取消 ${readState().success} 个。`);
      alert("B站关注数已为 0，自动清理完成。");
      return;
    }

    if (ready !== "ready") {
      writeState({ running: false });
      setStatus("没有等到关注列表加载，已停止。请刷新页面后重试。");
      return;
    }

    let pageSuccess = 0;

    while (isRunning() && pageSuccess < PAGE_SIZE) {
      if (hasPhoneVerification()) {
        await pauseForVerification();
        continue;
      }

      const result = await unfollowOne();

      if (result.status === "empty") break;

      if (result.status === "verification") {
        await pauseForVerification();
        continue;
      }

      if (result.status === "failed") {
        writeState({ running: false });
        setStatus(`账号“${result.account.name}”状态没有变化，已停止，避免误操作。`);
        return;
      }

      pageSuccess++;
      const state = writeState({ success: readState().success + 1 });
      setStatus(
        `本页 ${pageSuccess}/${PAGE_SIZE}；本次累计 ${state.success}。刚取消：${result.account.name}`,
      );

      const delay =
        MIN_DELAY_MS + Math.floor(Math.random() * (MAX_DELAY_MS - MIN_DELAY_MS + 1));
      await sleep(delay);
    }

    if (!isRunning()) {
      setStatus(`已手动停止。本次确认取消 ${readState().success} 个。`);
      return;
    }

    const total = await fetchLiveTotal();

    if (total === 0) {
      writeState({ running: false });
      setStatus(`完成：当前关注数为 0。本次确认取消 ${readState().success} 个。`);
      alert("B站关注数已为 0，自动清理完成。");
      return;
    }

    setStatus(
      total == null
        ? "本页完成，2 秒后刷新并继续。"
        : `当前剩余 ${total} 个，2 秒后刷新并继续。`,
    );

    await sleep(2000);

    if (isRunning()) location.reload();
  };

  startButton.addEventListener("click", () => {
    if (isRunning()) {
      setStatus("任务已经在运行。");
      return;
    }

    const confirmed = confirm(
      "将持续取消此账号的全部关注，并在每页完成后自动刷新续跑。\n\n" +
        "包括特别关注、自建分组和互关账号。是否开始？",
    );

    if (!confirmed) return;

    writeState({ running: true, success: 0, startedAt: new Date().toISOString() });
    setStatus("任务已开始，正在等待关注列表……");
    run();
  });

  stopButton.addEventListener("click", () => {
    writeState({ running: false });
    setStatus(`停止指令已生效。本次确认取消 ${readState().success} 个。`);
  });

  const state = readState();

  if (state.running) {
    setStatus(`检测到未完成任务，本次已确认取消 ${state.success} 个，自动继续……`);
    run();
  } else {
    setStatus("已暂停。点击“开始”后自动处理、刷新并续跑。");
  }
})();