#!/usr/bin/env node
/**
 * Customer-service department API: goodwill credits, CS notes.
 * Source of truth for balances remains zappier-edge admin.
 */
import http from 'node:http';
import fs from 'node:fs';
import path from 'node:path';

const PORT = Number(process.env.PORT || 3011);
const EDGE = (process.env.ZAPPIER_ADMIN_URL || 'http://127.0.0.1:3000').replace(/\/$/, '');
const KEY = process.env.ZAPPIER_ADMIN_KEY || 'admin-dev-key';
const STORE = process.env.CS_STORE || path.join(process.cwd(), 'data', 'credits.json');

function load() {
  try {
    return JSON.parse(fs.readFileSync(STORE, 'utf8'));
  } catch {
    return { credits: [] };
  }
}
function save(data) {
  fs.mkdirSync(path.dirname(STORE), { recursive: true });
  fs.writeFileSync(STORE, JSON.stringify(data, null, 2));
}

async function edge(pathname, { method = 'GET', body } = {}) {
  const r = await fetch(`${EDGE}${pathname}`, {
    method,
    headers: { 'content-type': 'application/json', 'x-admin-key': KEY },
    body: body ? JSON.stringify(body) : undefined,
  });
  const text = await r.text();
  try {
    return { status: r.status, body: JSON.parse(text) };
  } catch {
    return { status: r.status, body: text };
  }
}

const server = http.createServer(async (req, res) => {
  const url = new URL(req.url || '/', `http://127.0.0.1:${PORT}`);
  const json = (code, obj) => {
    res.writeHead(code, { 'content-type': 'application/json' });
    res.end(JSON.stringify(obj));
  };
  try {
    if (req.method === 'GET' && url.pathname === '/health') {
      return json(200, { ok: true, role: 'zappier-customer-service' });
    }
    if (req.method === 'POST' && url.pathname === '/credits') {
      const chunks = [];
      for await (const c of req) chunks.push(c);
      const payload = JSON.parse(Buffer.concat(chunks).toString('utf8') || '{}');
      const forwarded = await edge('/admin/api/credits', { method: 'POST', body: payload });
      const data = load();
      data.credits.unshift({ ...payload, at: new Date().toISOString(), edge: forwarded.status });
      save(data);
      return json(forwarded.status, forwarded.body);
    }
    if (req.method === 'GET' && url.pathname === '/credits') {
      const forwarded = await edge(`/admin/api/credits${url.search}`);
      return json(forwarded.status, forwarded.body);
    }
    json(404, { error: 'not found' });
  } catch (err) {
    json(502, { error: err.message });
  }
});

server.listen(PORT, '0.0.0.0', () => {
  process.stdout.write(`zappier-customer-service http://127.0.0.1:${PORT}/\n`);
});