"use strict";

const HOST_NAME = "com.easygoingaming.firefox_agent_bridge";
const RECONNECT_MS = 2000;

const ALLOWED = {
  "meta.ping": async () => ({ ok: true, extension: "firefox-agent-bridge" }),
  "meta.methods": async () => Object.keys(ALLOWED).sort(),
  "bookmarks.getTree": () => browser.bookmarks.getTree(),
  "bookmarks.getSubTree": (id) => browser.bookmarks.getSubTree(id),
  "bookmarks.getChildren": (id) => browser.bookmarks.getChildren(id),
  "bookmarks.get": (idOrIds) => browser.bookmarks.get(idOrIds),
  "bookmarks.search": (query) => browser.bookmarks.search(query),
  "bookmarks.create": (details) => browser.bookmarks.create(details),
  "bookmarks.update": (id, changes) => browser.bookmarks.update(id, changes),
  "bookmarks.move": (id, destination) => browser.bookmarks.move(id, destination),
  "bookmarks.remove": (id) => browser.bookmarks.remove(id),
  "bookmarks.removeTree": (id) => browser.bookmarks.removeTree(id),
  "bookmarks.getRecent": (numberOfItems) => browser.bookmarks.getRecent(numberOfItems),
};

let port = null;
let reconnectTimer = null;
let hostUp = false;
const adminWait = new Map();

function asArray(value) {
  if (value === undefined || value === null) {
    return [];
  }
  return Array.isArray(value) ? value : [value];
}

async function dispatchBookmark(message) {
  const method = message && message.method;
  const fn = ALLOWED[method];
  if (!fn) {
    throw new Error(`method not allowed: ${method || "(missing)"}`);
  }
  return fn(...asArray(message.args));
}

function adminCall(method, args) {
  if (!port) {
    return Promise.reject(new Error("native host is not connected"));
  }
  const id = crypto.randomUUID();
  return new Promise((resolve, reject) => {
    const timer = setTimeout(() => {
      adminWait.delete(id);
      reject(new Error("host did not answer"));
    }, 8000);
    adminWait.set(id, { resolve, reject, timer });
    port.postMessage({ type: "admin", id, method, args: args || [] });
  });
}

function attach(nextPort) {
  port = nextPort;
  hostUp = true;
  port.onMessage.addListener(async (message) => {
    if (message && message.type === "admin-result") {
      const pending = adminWait.get(message.id);
      if (!pending) {
        return;
      }
      adminWait.delete(message.id);
      clearTimeout(pending.timer);
      if (message.ok) {
        pending.resolve(message.result);
      } else {
        pending.reject(new Error(message.error || "admin failed"));
      }
      return;
    }
    const id = message && message.id;
    try {
      const result = await dispatchBookmark(message);
      port.postMessage({ id, ok: true, result });
    } catch (err) {
      port.postMessage({
        id,
        ok: false,
        error: err && err.message ? err.message : String(err),
      });
    }
  });
  port.onDisconnect.addListener(() => {
    port = null;
    hostUp = false;
    for (const [id, pending] of adminWait.entries()) {
      clearTimeout(pending.timer);
      pending.reject(new Error("native host disconnected"));
      adminWait.delete(id);
    }
    scheduleReconnect();
  });
}

function scheduleReconnect() {
  if (reconnectTimer) {
    return;
  }
  reconnectTimer = setTimeout(() => {
    reconnectTimer = null;
    connect();
  }, RECONNECT_MS);
}

function connect() {
  try {
    attach(browser.runtime.connectNative(HOST_NAME));
  } catch (err) {
    hostUp = false;
    console.error("native host connect failed", err);
    scheduleReconnect();
  }
}

browser.runtime.onMessage.addListener((message) => {
  const kind = message && message.type;
  if (kind === "status") {
    return Promise.resolve({ hostUp, port: 17634 });
  }
  if (kind === "admin") {
    return adminCall(message.method, message.args).then(
      (result) => ({ ok: true, result }),
      (err) => ({ ok: false, error: err.message })
    );
  }
  return undefined;
});

connect();