// sendy.js — silent newsletter opt-in via Sendy.
// API key from SENDY_API_KEY env, else DATA_DIR/sendy.key on the volume (same
// pattern as sendgrid.key). URL + list have safe non-secret defaults (the
// hashed list id is public — it appears in Sendy's own subscribe-form HTML).
// subscribe() is fire-and-forget and never throws: a Sendy hiccup must never
// break signup. boolean=true = silent (no confirmation email); Sendy itself
// refuses unsubscribed/bounced addresses, so opt-out always wins.
const https = require('https');
const fs = require('fs');
const path = require('path');

const DATA_DIR = process.env.DATA_DIR || path.join(__dirname, 'data');
const URL_BASE = (process.env.SENDY_URL || 'https://valuedreply.xyz').replace(/\/+$/, '');
const LIST = process.env.SENDY_LIST || 'W892hm1pgk3pIiK7OBYfHTWw'; // LinkSpin Newsletter (brand 3)

function apiKey() {
  if (process.env.SENDY_API_KEY) return process.env.SENDY_API_KEY.trim();
  try { return fs.readFileSync(path.join(DATA_DIR, 'sendy.key'), 'utf8').trim(); } catch (e) { return ''; }
}
function enabled() { return !!apiKey(); }

function subscribe(email, name) {
  const key = apiKey();
  const e = String(email || '').trim();
  if (!key || !e) return Promise.resolve(false);
  const body = new URLSearchParams({ api_key: key, list: LIST, email: e, name: String(name || ''), boolean: 'true' }).toString();
  const u = new URL(URL_BASE + '/subscribe');
  return new Promise(resolve => {
    const req = https.request({ hostname: u.hostname, path: u.pathname, method: 'POST',
      headers: { 'Content-Type': 'application/x-www-form-urlencoded', 'Content-Length': Buffer.byteLength(body) }, timeout: 10000 },
      res => { let d = ''; res.on('data', c => d += c); res.on('end', () => resolve(/^(1|true|already)/i.test(d.trim()))); });
    req.on('error', () => resolve(false));
    req.on('timeout', () => { req.destroy(); resolve(false); });
    req.end(body);
  });
}

// 'Subscribed' | 'Unsubscribed' | 'Unconfirmed' | 'Bounced' | 'Soft bounced' | 'Complained' | 'Email does not exist in list' | '' (no key / unreachable)
function status(email) {
  const key = apiKey(); const e = String(email || '').trim();
  if (!key || !e) return Promise.resolve('');
  const body = new URLSearchParams({ api_key: key, email: e, list_id: LIST }).toString();
  const u = new URL(URL_BASE + '/api/subscribers/subscription-status.php');
  return new Promise(resolve => {
    const req = https.request({ hostname: u.hostname, path: u.pathname, method: 'POST',
      headers: { 'Content-Type': 'application/x-www-form-urlencoded', 'Content-Length': Buffer.byteLength(body) }, timeout: 10000 },
      res => { let d = ''; res.on('data', c => d += c); res.on('end', () => resolve(d.trim().slice(0, 60))); });
    req.on('error', () => resolve('')); req.on('timeout', () => { req.destroy(); resolve(''); }); req.end(body);
  });
}
module.exports = { subscribe, enabled, status };