/**
 * Site configuration loader
 * Loads and manages site-wide settings from config.json
 *
 * Includes automatic migration from older config versions (see migrations.js).
 * Users never see the migration — it runs silently on startup, writes the
 * updated config back, and the rest of the app only ever sees the current
 * schema.
 */
const { validateConfig } = require('../../config-schema');
const { CADDY } = require('../../constants');
const { loadAndMigrate, CURRENT_VERSION } = require('./migrations');

const siteConfig = {
  tld: '.home',
  caName: '',
  dnsServerIp: '',
  dnsServerPort: CADDY.DEFAULT_DNS_PORT,
  dashboardHost: '',
  timezone: 'UTC',
  dnsServers: {},
  configurationType: 'homelab',
  domain: '',
  routingMode: 'subdomain'
};

function loadSiteConfig(CONFIG_FILE, log) {
  try {
    // Run migrations first — this handles config.json files from older
    // versions of DashCaddy and writes the migrated version back to disk.
    const raw = loadAndMigrate(CONFIG_FILE, log);

    if (raw && Object.keys(raw).length > 0) {
      // Validate config and log any issues
      const { valid, errors: configErrors, warnings: configWarnings } = validateConfig(raw);
      if (log && log.warn) {
        if (!valid) {
          log.warn('config', 'Config validation errors', { errors: configErrors });
        }
        for (const w of configWarnings) {
          log.warn('config', w);
        }
      }

      siteConfig.tld = raw.tld || '.home';
      if (!siteConfig.tld.startsWith('.')) siteConfig.tld = '.' + siteConfig.tld;
      siteConfig.caName = raw.caName || '';
      siteConfig.dnsServerIp = (raw.dns && raw.dns.ip) || '';
      siteConfig.dnsServerPort = (raw.dns && raw.dns.port) || CADDY.DEFAULT_DNS_PORT;
      siteConfig.dashboardHost = raw.dashboardHost || `status${siteConfig.tld}`;
      siteConfig.timezone = raw.timezone || 'UTC';
      siteConfig.dnsServers = raw.dnsServers || {};
      siteConfig.configurationType = raw.configurationType || 'homelab';
      siteConfig.domain = raw.domain || '';
      siteConfig.routingMode = raw.routingMode || 'subdomain';
      siteConfig.pylon = raw.pylon || null;
    }
  } catch (e) {
    if (log && log.error) {
      log.error('config', 'Failed to load site config', { error: e.message });
    }
  }
}

/** Build a domain from subdomain + configured TLD or public domain */
function buildDomain(subdomain) {
  if (siteConfig.configurationType === 'public' && siteConfig.domain) {
    return `${subdomain}.${siteConfig.domain}`;
  }
  return `${subdomain}${siteConfig.tld}`;
}

/** Build full service URL (protocol + host + path) */
function buildServiceUrl(subdomain) {
  if (siteConfig.routingMode === 'subdirectory' && siteConfig.domain) {
    return `https://${siteConfig.domain}/${subdomain}`;
  }
  return `https://${buildDomain(subdomain)}`;
}

module.exports = {
  siteConfig,
  loadSiteConfig,
  buildDomain,
  buildServiceUrl,
  CURRENT_VERSION
};