const Koa = require("koa");
const fs = require("fs");
const path = require("path");
const { promisify } = require("util");
const Router = require("@koa/router");
const cors = require("@koa/cors");
const dayjs = require("dayjs");
const { Server } = require("socket.io");
const { createServer } = require("http");
const { bot, getDisplayName } = require("./bot.js");
const { config } = require("./config.js");
const {
  textSHA1,
  ensureAvatarDir,
  ensureUploadDir,
  composeAvatarFileName,
} = require("./util.js");

const DEFAULT_ROOM = "default_room";

const app = new Koa();
const router = new Router();
const httpServer = createServer(app.callback());
const io = new Server(httpServer, {
  cors: true,
  path: "/socket.io",
});
const activeSessions = new Set();

io.use((socket, next) => {
  const auth = socket.handshake.auth;
  if (!auth) {
    next(Error("认证失败"));
    return;
  }
  const appName = auth.appName;
  const appCode = config.appCode[appName];
  if (!appCode || appCode !== auth.appCode) {
    next(Error("认证失败"));
    return;
  }
  if (textSHA1(auth.passphrase) !== config.appAuthHash[appName]) {
    next(Error("口令错误"));
    return;
  }
  if (bot?.state !== bot.CONF.STATE.login) {
    next(Error("服务不可用"));
    return;
  }
  next().then(() => {
    bot.sendText(
      `【上线通知】
  DATETIME: ${dayjs().format("YYYY-MM-DDTHH:MM:ss")}
  APP_NAME: ${appName}
  PLATFORM: ${auth.platform || ""}`,
      "filehelper"
    );
  });
});

function deactivateSession() {
  activeSessions.delete(socket.id);
}

async function pushMessage(message) {
  if (message.filename) {
    for (const sid of await io.allSockets()) {
      const msg = {
        ...message,
        fileUrl: `${config.baseUrl}/session/${sid}/media/${message.composedID}/${message.filename}`,
      };
      io.to(sid).emit("message", msg);
    }
  } else {
    io.in(DEFAULT_ROOM).emit("message", message);
  }
}

function login(sessionID) {
  const u = bot.user;
  return {
    id: u.UserName,
    nickname: u.NickName,
    displayName: u.NickName,
    signature: u.Signature,
    avatar: `${config.baseUrl}/session/${sessionID}/avatar/${u.UserName}`,
  };
}
function getContacts(sessionID) {
  function wrapContact(contact) {
    return {
      id: contact.UserName,
      nickname: contact.NickName,
      displayName: getDisplayName(contact),
      signature: contact.Signature,
      nameInitial: contact.PYInitial || contact.RemarkPYInitial,
      nameQuanPin: contact.PYQuanPin || contact.RemarkPYQuanPin,
      avatar: `${config.baseUrl}/session/${sessionID}/avatar/${contact.UserName}`,
      isFriend: contact.ContactFlag === 1,
    };
  }
  const data = { contacts: [], specialContacts: [], groups: [] };
  for (const uid of Object.keys(bot.contacts)) {
    const contact = bot.contacts[uid];
    if (bot.Contact.isPublicContact(contact)) {
      continue;
    } else if (bot.Contact.isSpContact(contact)) {
      if (["filehelper"].includes(contact.UserName)) {
        data.specialContacts.push(wrapContact(contact));
      }
      continue;
    } else if (bot.Contact.isRoomContact(contact)) {
      data.groups.push(wrapContact(contact));
    } else if (!contact.isSelf) {
      data.contacts.push(wrapContact(contact));
    }
  }
  return data;
}
async function sendMessage({ type, target, filename, fileUri, data }) {
  const targetContact = bot.contacts[target];
  if (!targetContact) {
    return "联系人不存在";
  }
  const to = targetContact.UserName;
  switch (type) {
    case "text":
      await bot.sendText(data, target);
      break;
    case "emotion":
      await bot.sendEmoticon(data, to);
      break;
    case "img":
    case "video":
    case "file": {
      const filepath = path.join(ensureUploadDir(), fileUri);
      if (!fs.existsSync(filepath)) {
        return "图片不存在";
      }
      let mediaId;
      try {
        const { mediaId: id } = await bot.uploadMedia(
          fs.createReadStream(filepath),
          filename,
          targetContact.UserName
        );
        mediaId = id;
      } catch {
        return "上传文件到远程服务器失败";
      }
      try {
        if (type === "img") {
          await bot.sendPic(mediaId, to);
        } else if (type === "video") {
          await bot.sendVideo(mediaId, to);
        } else {
          await bot.sendDoc(
            mediaId,
            filename,
            fs.statSync(filepath).size,
            path.extname(filepath),
            to
          );
        }
      } catch (e) {
        return e?.tips || e?.message || "消息发送失败";
      }
      break;
    }
  }
}
async function revokeMessage({ msgID, target }) {
  await bot.revokeMsg(msgID, target);
}
async function uploadFile({ data }) {
  const uploadDir = ensureUploadDir();
  const filename = dayjs().format("YYYYMMDD_") + String(Math.random()).slice(1);
  const filepath = path.join(uploadDir, filename);
  await promisify(fs.writeFile)(filepath, data);
  // 10分钟后删除上传的临时文件
  setTimeout(() => {
    if (fs.existsSync(filepath)) {
      fs.rmSync(filepath);
    }
  }, 600000);
  return { localFileName: filename };
}
function handleNotImplemented(_, cb) {
  cb?.call(null, "Not Implemented");
}

io.on("connection", (socket) => {
  console.log("connected");
  activeSessions.add(socket.id);
  socket.join(DEFAULT_ROOM);
  socket.on("disconnect", deactivateSession);
  socket.on("login", login.bind(null, socket.id));
  socket.on("get_contacts", getContacts.bind(null, socket.id));
  socket.on("send_message", sendMessage);
  socket.on("revoke_message", revokeMessage);
  socket.on("upload_file", uploadFile);
  socket.onAny(handleNotImplemented);
  socket.use((_, next) => {
    if (bot?.state !== bot.CONF.STATE.login) {
      return next(Error("服务不可用"));
    }
    next();
  });
});

/** 获取头像 */
router.get("/session/:sessionID/avatar/:userID", (ctx, next) => {
  if (!activeSessions.has(ctx.params.sessionID)) {
    ctx.throw(401);
  }
  const contact = bot.contacts[ctx.params.userID];
  if (!contact) {
    ctx.throw(404);
  }
  const filename = composeAvatarFileName(contact);
  const filepath = filename && path.join(ensureAvatarDir(), filename);
  if (filepath && fs.existsSync(filepath)) {
    ctx.response.headers["Content-Type"] = "image/jpeg";
    ctx.response.body = fs.createReadStream(filepath);
  } else {
    ctx.throw(404);
  }
  next();
});
/** 获取消息文件，包含图片 */
router.get("/session/:sessionID/media/:composedID/:filename", (ctx, next) => {
  const filename = composeMediaFilePathFromID(
    ctx.params.composedID,
    ctx.params.filename
  );
  if (fs.existsSync(filename)) {
    ctx.response.body = fs.createReadStream(filename);
  } else {
    ctx.throw(404);
  }
  next();
});

app.use(cors());
app.use(router.routes());
httpServer.listen(config.httpPort, config.httpHost);

module.exports = {
  pushMessage,
};