Function writeConfig

src/setup/wizard.ts:579–721

Write the assembled config to disk, merging with existing values.

(picks: {
  primaryModel: string;
  provider: string;
  primaryDetected?: DetectedModel;
  subagentMode: 'off' | 'sequential' | 'parallel';
  subagentRole?: { provider: string; model: string };
  subagentDetected?: DetectedModel;
  visionRole?: { provider: string; model: string };
  visionDetected?: DetectedModel;
  anthropicCaching: boolean;
  autoSnapshot: boolean;
  hardware: HardwareProfile;
})

/** Write the assembled config to disk, merging with existing values. */
async function writeConfig(picks: {
  primaryModel: string;
  provider: string;
  primaryDetected?: DetectedModel;
  subagentMode: 'off' | 'sequential' | 'parallel';
  subagentRole?: { provider: string; model: string };
  subagentDetected?: DetectedModel;
  visionRole?: { provider: string; model: string };
  visionDetected?: DetectedModel;
  anthropicCaching: boolean;
  autoSnapshot: boolean;
  hardware: HardwareProfile;
}): Promise<void> {
  await fs.mkdir(QODEX_HOME, { recursive: true });

  await withLock(QODEX_CONFIG_FILE + '.lock', async () => {
  // Try to load existing config and merge; if missing, start from DEFAULT_CONFIG.
  let existing: QodexConfig;
  try {
    existing = await loadConfig(process.cwd());
  } catch (err: any) {
    if (err?.code === 'ENOENT') {
      // No config yet — fresh start.
      existing = JSON.parse(JSON.stringify(DEFAULT_CONFIG));
    } else {
      // A real parse/IO error (corrupt YAML, permission denied, etc.). Do NOT
      // silently reset over the user's config. Back the existing file up to a
      // timestamped copy first, warn loudly, then continue from defaults so the
      // original data is preserved on disk and recoverable.
      const backup = `${QODEX_CONFIG_FILE}.bak-${new Date().toISOString().replace(/[:.]/g, '-')}`;
      let backedUp = false;
      try {
        await fs.copyFile(QODEX_CONFIG_FILE, backup);
        backedUp = true;
      } catch {
        // If even the backup fails, fall through to the abort below.
      }
      if (!backedUp) {
        throw new Error(
          `Could not read existing config at ${QODEX_CONFIG_FILE} (${err?.message ?? err}), ` +
          `and could not back it up before overwriting. Aborting to avoid losing your settings. ` +
          `Fix or move ${QODEX_CONFIG_FILE} aside, then re-run \`qx setup\`.`,
        );
      }
      console.error(
        `⚠ Could not read existing config at ${QODEX_CONFIG_FILE} (${err?.message ?? err}).\n` +
        `  Your previous config was backed up to ${backup} before continuing from defaults.`,
      );
      existing = JSON.parse(JSON.stringify(DEFAULT_CONFIG));
    }
  }

  const updated: QodexConfig = {
    ...existing,
    defaults: {
      ...existing.defaults,
      provider: picks.provider,
      model: picks.primaryModel,