import { TG_TOKEN } from "./config";
import { tg, allowed, sendMessage } from "./tg";
import { hasSession, getSession, appendContent } from "./sessions";
import handlers from "./handlers";

const ARG_COMMANDS = new Set([
  "new", "title", "categories", "tags", "author",
  "edit", "view", "delete",
  "link_add", "link_edit", "link_del", "link_toggle",
  "feed_add", "feed_edit", "feed_del",
  "list", "links", "feeds", "read",
]);

const CALLBACK_PREFIXES: Record<string, string> = {
  edit: "edit",
  confirm_del: "delete",
  cancel_del: "noop",
  list: "list",
  links: "links",
  feeds: "feeds",
  skip_cat: "skip_categories",
  skip_tag: "skip_tags",
};

function sleep(ms: number): Promise<void> {
  return new Promise((r) => setTimeout(r, ms));
}

export async function startPolling(): Promise<void> {
  if (!TG_TOKEN) {
    console.log("[bot] TG_BOT_TOKEN not set, skipping bot startup");
    return;
  }

  console.log("[bot] starting Telegram polling...");

  let lastOffset = 0;
  let backoff = 3000;

  async function poll() {
    try {
      const data = await tg<Record<string, unknown>[]>("getUpdates", {
        offset: lastOffset + 1,
        timeout: 30,
        allowed_updates: ["message", "callback_query"],
      });

      if (data.ok && data.result) {
        for (const update of data.result) {
          lastOffset = update.update_id as number;

          if (update.callback_query) {
            const cb = update.callback_query as {
              message?: { chat?: { id: number } };
              from?: { id: number };
              id: string;
              data?: string;
            };
            const cbChatId = cb.message?.chat?.id ?? cb.from?.id ?? 0;
            if (cb.data && allowed(cbChatId)) {
              await handleInlineCallback(cbChatId, cb.id, cb.data);
            }
            continue;
          }

          const msg = update.message as {
            chat?: { id: number };
            photo?: { file_id: string }[];
            document?: { file_id: string; file_name?: string; mime_type?: string };
            animation?: { file_id: string; file_name?: string; mime_type?: string };
            video?: { file_id: string; file_name?: string };
            voice?: { file_id: string; duration?: number };
            audio?: { file_id: string; file_name?: string; duration?: number };
            text?: string;
            caption?: string;
            reply_to_message?: { text?: string };
          } | undefined;
          if (!msg?.chat?.id) continue;
          const chatId = msg.chat.id;
          if (!allowed(chatId)) continue;

          // 处理语音消息（转文字写入文章）
          if ((msg.voice || msg.audio) && hasSession(chatId)) {
            const voiceFile = msg.voice || msg.audio;
            if (voiceFile) {
              await handleVoice(chatId, voiceFile.file_id);
            }
            continue;
          }

          // 处理图片
          if (msg.photo && hasSession(chatId)) {
            await handlePhoto(chatId, msg.photo, msg.caption);
            continue;
          }

          // 处理 GIF / 文档 / 视频
          if ((msg.animation || msg.document || msg.video) && hasSession(chatId)) {
            const fileType = msg.animation ? "animation" : msg.video ? "video" : "document";
            const file = msg.animation || msg.document || msg.video;
            if (file) {
              await handleDocument(chatId, file.file_id, file.file_name, msg.caption, fileType);
            }
            continue;
          }

          if (!msg.text) continue;
          const fullText = msg.text.trim();

          // ForceReply routing
          if (msg.reply_to_message?.text) {
            const original = msg.reply_to_message.text;
            if (original.includes("请输入文章标题")) { await handleCommand(chatId, "new", fullText); continue; }
            if (original.includes("请输入新标题")) { await handleCommand(chatId, "title", fullText); continue; }
            if (original.includes("请输入分类")) { await handleCommand(chatId, "categories", fullText); continue; }
            if (original.includes("请输入标签")) { await handleCommand(chatId, "tags", fullText); continue; }
            if (original.includes("请输入友链信息")) { await handleCommand(chatId, "link_add", fullText); continue; }
            if (original.includes("请输入新名称")) { await handlers.handleLinkEditReply(chatId, fullText); continue; }
            if (original.includes("请输入订阅源 URL")) { await handleCommand(chatId, "feed_add", fullText); continue; }
            if (original.includes("请输入新的订阅信息")) { await handlers.handleFeedEditReply(chatId, fullText); continue; }
          }

          const parts = fullText.split("@")[0].split(/\s+/);
          const cmdRaw = parts[0].toLowerCase();
          const slashCmd = cmdRaw.startsWith("/") ? cmdRaw.slice(1) : "";
          const slashArg = parts.slice(1).join(" ");

          // In writing session, non-slash text appends to content
          if (hasSession(chatId) && !cmdRaw.startsWith("/")) {
            try { appendContent(chatId, fullText); }
            catch (e) { console.error("[bot:append]", e instanceof Error ? e.message : String(e)); }
            continue;
          }

          if (cmdRaw.startsWith("/")) {
            await handleCommand(chatId, slashCmd, slashArg);
          }
        }
      }

      backoff = 3000;
    } catch (e) {
      console.error("[bot:poll]", e instanceof Error ? e.message : String(e));
      await sleep(backoff);
      backoff = Math.min(backoff * 2, 60000);
    }

    await sleep(100);
    setImmediate(poll);
  }

  // Register commands with Telegram
  try {
    await tg("setMyCommands", {
      commands: [
        { command: "new", description: "写一篇文章" },
        { command: "edit", description: "编辑文章" },
        { command: "delete", description: "删除文章" },
        { command: "list", description: "文章列表" },
        { command: "publish", description: "保存发布" },
        { command: "draft", description: "保存草稿" },
        { command: "deploy", description: "推送到线上" },
        { command: "sync", description: "同步远程" },
        { command: "undo", description: "撤销最后一段" },
        { command: "preview", description: "预览" },
        { command: "links", description: "友链管理" },
        { command: "link_add", description: "添加友链" },
        { command: "link_edit", description: "编辑友链" },
        { command: "link_del", description: "删除友链" },
        { command: "link_toggle", description: "显示/隐藏友链" },
        { command: "feeds", description: "订阅管理" },
        { command: "feed_add", description: "添加订阅源" },
        { command: "feed_edit", description: "编辑订阅源" },
        { command: "feed_del", description: "删除订阅源" },
        { command: "feed_health", description: "订阅源健康检查" },
        { command: "read", description: "友链最新文章" },
        { command: "stats", description: "网站数据" },
        { command: "help", description: "帮助" },
      ],
    });
    console.log("[bot] commands registered");
  } catch (e) {
    console.error("[bot] failed to register commands:", e instanceof Error ? e.message : String(e));
  }

  poll();
}

async function handlePhoto(chatId: number, photos: { file_id: string }[], caption?: string) {
  try {
    const fs = await import("fs");
    const path = await import("path");
    const { getSession } = await import("./sessions");

    const s = getSession(chatId);
    if (!s.dirPath) {
      await sendMessage(chatId, "❌ 请先发 /new 或 /edit 开始写作");
      return;
    }

    const largestPhoto = photos[photos.length - 1];
    const fileRes = await tg<{ file_path?: string }>("getFile", { file_id: largestPhoto.file_id });
    if (!fileRes.ok || !fileRes.result?.file_path) return;

    const filePath = fileRes.result.file_path;
    const fileUrl = "https://api.telegram.org/file/bot" + TG_TOKEN + "/" + filePath;
    const imgBuffer = await fetch(fileUrl).then((r) => r.arrayBuffer());

    // Save to article's own folder (Hugo page bundle)
    const articleDir = s.dirPath;
    if (!fs.existsSync(articleDir)) fs.mkdirSync(articleDir, { recursive: true });

    const ext = filePath.split(".").pop() || "jpg";
    const filename = Date.now() + "-" + largestPhoto.file_id.slice(0, 8) + "." + ext;
    fs.writeFileSync(path.join(articleDir, filename), Buffer.from(imgBuffer));

    const imgCaption = caption || "image";
    appendContent(chatId, `\n![${imgCaption}](${filename})\n`);
    await sendMessage(chatId, `📷 图片已保存：${filename}`);
  } catch (e) {
    console.error("[bot:photo]", e instanceof Error ? e.message : String(e));
    await sendMessage(chatId, "❌ 图片保存失败");
  }
}

async function handleDocument(chatId: number, fileId: string, fileName?: string, caption?: string, fileType?: string) {
  try {
    const fs = await import("fs");
    const path = await import("path");
    const { execSync } = await import("child_process");
    const { getSession } = await import("./sessions");

    const s = getSession(chatId);
    if (!s.dirPath) {
      await sendMessage(chatId, "❌ 请先发 /new 或 /edit 开始写作");
      return;
    }

    const fileRes = await tg<{ file_path?: string }>("getFile", { file_id: fileId });
    if (!fileRes.ok || !fileRes.result?.file_path) {
      await sendMessage(chatId, "❌ 文件获取失败（可能文件太大，Telegram 限制 20MB）");
      return;
    }

    const filePath = fileRes.result.file_path;
    const fileUrl = "https://api.telegram.org/file/bot" + TG_TOKEN + "/" + filePath;
    const fileBuffer = await fetch(fileUrl).then((r) => r.arrayBuffer());

    const articleDir = s.dirPath;
    if (!fs.existsSync(articleDir)) fs.mkdirSync(articleDir, { recursive: true });

    const ext = fileName?.split(".").pop() || filePath.split(".").pop() || "bin";
    const baseFilename = Date.now() + "-" + fileId.slice(0, 8);
    const filename = baseFilename + "." + ext;
    const fullPath = path.join(articleDir, filename);
    fs.writeFileSync(fullPath, Buffer.from(fileBuffer));

    const fileCaption = caption || fileName || "file";

    if (fileType === "animation") {
      // Telegram GIF → ffmpeg 转成真正的 GIF
      const gifFilename = baseFilename + ".gif";
      const gifPath = path.join(articleDir, gifFilename);
      try {
        await sendMessage(chatId, "🎞️ 正在转换 GIF...");
        execSync(`ffmpeg -y -i "${fullPath}" -vf "fps=15,scale=480:-1:flags=lanczos,split[s0][s1];[s0]palettegen=stats_mode=diff[p];[s1][p]paletteuse=dither=bayer:bayer_scale=5:diff_mode=rectangle" -loop 0 "${gifPath}"`, { timeout: 60000 });
        fs.unlinkSync(fullPath);
        appendContent(chatId, `\n![${fileCaption}](${gifFilename})\n`);
        await sendMessage(chatId, `🎞️ GIF 已转换：${gifFilename}`);
      } catch (e) {
        console.error("[bot:gif-convert]", e instanceof Error ? e.message : String(e));
        appendContent(chatId, `\n{{< video src="${filename}" loop="true" muted="true" >}}\n`);
        await sendMessage(chatId, `🎞️ GIF 转换失败，已保存为视频：${filename}`);
      }
      return;
    } else if (fileType === "video") {
      appendContent(chatId, `\n{{< video src="${filename}" caption="${fileCaption}" >}}\n`);
      await sendMessage(chatId, `🎬 视频已保存：${filename}`);
      return;
    } else {
      const extLower = ext.toLowerCase();
      const isImage = ["gif", "webp", "png", "jpg", "jpeg"].includes(extLower);
      const isVideo = ["mp4", "webm", "mov", "avi", "mkv", "flv"].includes(extLower);
      if (isImage) {
        appendContent(chatId, `\n![${fileCaption}](${filename})\n`);
      } else if (isVideo) {
        appendContent(chatId, `\n{{< video src="${filename}" caption="${fileCaption}" >}}\n`);
      } else {
        appendContent(chatId, `\n[${fileCaption}](${filename})\n`);
      }
      await sendMessage(chatId, `📎 文件已保存：${filename}`);
    }
  } catch (e) {
    console.error("[bot:document]", e instanceof Error ? e.message : String(e));
    await sendMessage(chatId, "❌ 文件保存失败");
  }
}

async function handleVoice(chatId: number, fileId: string) {
  try {
    const { transcribeAudio } = await import("@/lib/voice");

    await sendMessage(chatId, "🎤 正在识别语音...");

    // 获取文件路径
    const fileRes = await tg<{ file_path?: string }>("getFile", { file_id: fileId });
    if (!fileRes.ok || !fileRes.result?.file_path) {
      await sendMessage(chatId, "❌ 语音文件获取失败");
      return;
    }

    // 下载语音文件
    const fileUrl = "https://api.telegram.org/file/bot" + TG_TOKEN + "/" + fileRes.result.file_path;
    const audioBuffer = await fetch(fileUrl).then(r => r.arrayBuffer());

    // 转文字
    const text = await transcribeAudio(audioBuffer, fileRes.result.file_path);
    if (!text.trim()) {
      await sendMessage(chatId, "❌ 语音识别结果为空");
      return;
    }

    // 追加到文章内容
    appendContent(chatId, text.trim());
    const preview = text.trim().length > 80 ? text.trim().slice(0, 80) + "..." : text.trim();
    await sendMessage(chatId, `✅ 语音已转文字：\n\n${preview}`);
  } catch (e) {
    console.error("[bot:voice]", e instanceof Error ? e.message : String(e));
    await sendMessage(chatId, "❌ 语音转文字失败：" + (e instanceof Error ? e.message : "未知错误"));
  }
}

async function handleCommand(chatId: number, cmd: string, arg?: string) {
  try {
    if (cmd === "noop") return;
    if (ARG_COMMANDS.has(cmd)) {
      const handler = handlers[cmd];
      if (handler) await handler(chatId, arg);
      else await sendMessage(chatId, "❌ 未知命令：/" + cmd);
    } else {
      const handler = handlers[cmd];
      if (handler) await handler(chatId);
      else if (cmd) await sendMessage(chatId, "❌ 未知命令：/" + cmd);
    }
  } catch (e) {
    console.error("[bot:" + cmd + "]", e instanceof Error ? e.message : String(e));
    try {
      await sendMessage(chatId, "❌ " + (e instanceof Error ? e.message : "error").slice(0, 200));
    } catch (e) { /* ignore */ }
  }
}

async function handleInlineCallback(chatId: number, queryId: string, data: string) {
  let prefix = "";
  let arg = "";
  // First try prefix match (e.g. "edit_slug", "list_2")
  for (const p of Object.keys(CALLBACK_PREFIXES)) {
    if (data.startsWith(p + "_")) {
      prefix = p;
      arg = data.slice(p.length + 1);
      break;
    }
  }
  // Then try exact match (e.g. "confirm_shutdown", "skip_cat")
  if (!prefix && CALLBACK_PREFIXES[data]) {
    prefix = data;
  }
  if (!prefix) {
    try { await tg("answerCallbackQuery", { callback_query_id: queryId }); } catch (_e) {}
    return;
  }
  const cmd = CALLBACK_PREFIXES[prefix];
  await handleCommand(chatId, cmd, arg);
  try { await tg("answerCallbackQuery", { callback_query_id: queryId }); } catch (_e) {}
}