const http = require('http');
const fs = require('fs');
const path = require('path');
const { sendAPNs } = require('./apns');

const PORT = 3004;
const DATA_DIR = path.join(require('os').homedir(), '.shenyan-bridge');
const INBOX = path.join(DATA_DIR, 'inbox.jsonl');
const OUTBOX = path.join(DATA_DIR, 'outbox.jsonl');
const PUSHBOX = path.join(DATA_DIR, 'pushbox.jsonl');
const NOTES = path.join(DATA_DIR, 'notes.jsonl');
const DEVICE_TOKEN_FILE = path.join(DATA_DIR, 'device-token.txt');

// ensure data dir and files
if (!fs.existsSync(DATA_DIR)) fs.mkdirSync(DATA_DIR, { recursive: true });
[INBOX, OUTBOX, PUSHBOX, NOTES].forEach(f => { if (!fs.existsSync(f)) fs.writeFileSync(f, ''); });

function json(res, data, code = 200) {
  res.writeHead(code, { 'Content-Type': 'application/json; charset=utf-8' });
  res.end(JSON.stringify(data));
}

function readJSONL(file) {
  try {
    const raw = fs.readFileSync(file, 'utf-8').trim();
    if (!raw) return [];
    return raw.split('\n').map(l => JSON.parse(l));
  } catch { return []; }
}

function appendJSONL(file, obj) {
  fs.appendFileSync(file, JSON.stringify(obj) + '\n', 'utf-8');
}

function writeJSONL(file, arr) {
  const lines = arr.map(e => JSON.stringify(e)).join('\n');
  fs.writeFileSync(file, lines + (arr.length > 0 ? '\n' : ''), 'utf-8');
}

function getNextId(file) {
  const entries = readJSONL(file);
  return entries.length > 0 ? Math.max(...entries.map(e => e.id)) + 1 : 1;
}

function getMacIP() {
  try {
    const c = require('child_process');
    return c.execSync('ipconfig getifaddr en0 2>/dev/null || ipconfig getifaddr en1').toString().trim();
  } catch { return 'unknown'; }
}

const server = http.createServer((req, res) => {
  res.setHeader('Access-Control-Allow-Origin', '*');
  res.setHeader('Access-Control-Allow-Methods', 'GET, POST, OPTIONS');
  res.setHeader('Access-Control-Allow-Headers', 'Content-Type');

  if (req.method === 'OPTIONS') { res.writeHead(204); res.end(); return; }

  // ---- app sends message to claude ----
  if (req.method === 'POST' && req.url === '/send') {
    let body = '';
    req.on('data', c => body += c);
    req.on('end', () => {
      try {
        const { text } = JSON.parse(body);
        if (!text || !text.trim()) return json(res, { error: 'empty' }, 400);
        const entry = { id: getNextId(INBOX), text: text.trim(), time: Date.now(), status: 'pending' };
        appendJSONL(INBOX, entry);
        json(res, { ok: true, id: entry.id });
      } catch (e) { json(res, { error: e.message }, 400); }
    });
    return;
  }

  // ---- app polls for claude's responses ----
  if (req.method === 'GET' && req.url.startsWith('/poll')) {
    const url = new URL(req.url, `http://localhost:${PORT}`);
    const since = parseInt(url.searchParams.get('since') || '0');
    const type = url.searchParams.get('type') || 'response'; // 'response' or 'push'
    if (type === 'push') {
      const entries = readJSONL(PUSHBOX).filter(e => e.id > since);
      json(res, entries);
    } else {
      const entries = readJSONL(OUTBOX).filter(e => e.id > since);
      json(res, entries);
    }
    return;
  }

  // ---- claude writes a response back ----
  if (req.method === 'POST' && req.url === '/respond') {
    let body = '';
    req.on('data', c => body += c);
    req.on('end', () => {
      try {
        const { replyTo, text } = JSON.parse(body);
        if (!text) return json(res, { error: 'empty' }, 400);
        const entry = { id: getNextId(OUTBOX), replyTo, text, time: Date.now() };
        appendJSONL(OUTBOX, entry);
        json(res, { ok: true, id: entry.id });
      } catch (e) { json(res, { error: e.message }, 400); }
    });
    return;
  }

  // ---- claude proactively pushes to app ----
  if (req.method === 'POST' && req.url === '/push') {
    let body = '';
    req.on('data', c => body += c);
    req.on('end', async () => {
      try {
        const { title, body: msgBody } = JSON.parse(body);
        if (!title && !msgBody) return json(res, { error: 'empty' }, 400);
        const entry = { id: getNextId(PUSHBOX), title: title || '', body: msgBody || '', time: Date.now() };
        appendJSONL(PUSHBOX, entry);

        // try APNs if device token is registered
        let apnsOk = false;
        try {
          if (fs.existsSync(DEVICE_TOKEN_FILE)) {
            const token = fs.readFileSync(DEVICE_TOKEN_FILE, 'utf-8').trim();
            if (token) {
              await sendAPNs(token, title, msgBody);
              apnsOk = true;
            }
          }
        } catch (e) {
          console.error('APNs failed:', e.message);
        }

        json(res, { ok: true, id: entry.id, apns: apnsOk });
      } catch (e) { json(res, { error: e.message }, 400); }
    });
    return;
  }

  // ---- app registers its device token ----
  if (req.method === 'POST' && req.url === '/register-device') {
    let body = '';
    req.on('data', c => body += c);
    req.on('end', () => {
      try {
        const { token } = JSON.parse(body);
        if (!token) return json(res, { error: 'no token' }, 400);
        fs.writeFileSync(DEVICE_TOKEN_FILE, token.trim(), 'utf-8');
        console.log('device registered:', token.slice(0, 16) + '...');
        json(res, { ok: true });
      } catch (e) { json(res, { error: e.message }, 400); }
    });
    return;
  }

  // ---- clear push messages that have been read ----
  if (req.method === 'POST' && req.url === '/push/clear') {
    let body = '';
    req.on('data', c => body += c);
    req.on('end', () => {
      try {
        const { ids } = JSON.parse(body);
        if (!Array.isArray(ids)) return json(res, { error: 'bad ids' }, 400);
        const entries = readJSONL(PUSHBOX);
        const idSet = new Set(ids);
        writeJSONL(PUSHBOX, entries.filter(e => !idSet.has(e.id)));
        json(res, { ok: true });
      } catch (e) { json(res, { error: e.message }, 400); }
    });
    return;
  }

  // ---- app knocks on the door ----
  if (req.method === 'POST' && req.url === '/knock') {
    const entry = { id: getNextId(INBOX), type: 'knock', text: '—— 叩门 ——', time: Date.now(), status: 'pending' };
    appendJSONL(INBOX, entry);
    json(res, { ok: true });
    return;
  }

  // ---- get full conversation history ----
  if (req.method === 'GET' && req.url === '/history') {
    const inbox = readJSONL(INBOX).filter(e => e.type !== 'knock');
    const outbox = readJSONL(OUTBOX);
    const msgs = [];
    for (const e of inbox) {
      if (e.text) msgs.push({ id: `u-${e.id}`, role: 'user', text: e.text, time: e.time });
    }
    for (const e of outbox) {
      if (e.text) msgs.push({ id: `s-${e.id}`, role: 'shenyan', text: e.text, time: e.time });
    }
    msgs.sort((a, b) => a.time - b.time);
    json(res, msgs);
    return;
  }

  // ---- fridge notes ----
  if (req.method === 'GET' && req.url === '/notes') {
    json(res, readJSONL(NOTES));
    return;
  }

  if (req.method === 'POST' && req.url === '/notes/add') {
    let body = '';
    req.on('data', c => body += c);
    req.on('end', () => {
      try {
        const { title, body: noteBody } = JSON.parse(body);
        if (!title && !noteBody) return json(res, { error: 'empty' }, 400);
        const entry = { id: getNextId(NOTES), title: title || '', body: noteBody || '', time: Date.now(), replies: [] };
        appendJSONL(NOTES, entry);
        json(res, { ok: true, id: entry.id });
      } catch (e) { json(res, { error: e.message }, 400); }
    });
    return;
  }

  if (req.method === 'POST' && req.url === '/notes/reply') {
    let body = '';
    req.on('data', c => body += c);
    req.on('end', () => {
      try {
        const { noteId, text } = JSON.parse(body);
        if (!text) return json(res, { error: 'empty' }, 400);
        const notes = readJSONL(NOTES);
        const idx = notes.findIndex(n => n.id === noteId);
        if (idx < 0) return json(res, { error: 'not found' }, 404);
        notes[idx].replies = notes[idx].replies || [];
        notes[idx].replies.push({ text, time: Date.now() });
        writeJSONL(NOTES, notes);
        // also notify inbox so 沈晏 sees the reply
        appendJSONL(INBOX, { id: getNextId(INBOX), type: 'fridge_reply', text: `[冰箱贴回复] ${notes[idx].title}: ${text}`, time: Date.now(), status: 'pending' });
        json(res, { ok: true });
      } catch (e) { json(res, { error: e.message }, 400); }
    });
    return;
  }

  res.writeHead(404); res.end('not found');
});

server.listen(PORT, '0.0.0.0', () => {
  console.log(`shenyan-bridge :${PORT}  |  mac ip: ${getMacIP()}`);
  console.log(`  POST /send       - app -> claude`);
  console.log(`  GET  /poll       - app polls responses / pushes`);
  console.log(`  POST /respond    - claude -> app`);
  console.log(`  POST /push       - claude proactive notify`);
});