/**
 * Trigger-service config. All env-resolved; the service token falls back to the
 * 0600 plum secret file. No secrets are baked in.
 */
import { readFileSync } from 'node:fs';
import { homedir } from 'node:os';
import { join } from 'node:path';

function fileOrEnv(envVar: string, file: string): string {
  if (process.env[envVar]) return process.env[envVar] as string;
  try {
    return readFileSync(file, 'utf8').trim();
  } catch {
    return '';
  }
}

export interface ServiceConfig {
  readonly port: number;
  /** Bearer token Prospector must present to POST /api/screening/requests. */
  readonly serviceToken: string;
  /** Absolute path to client/mr_lookup.py. */
  readonly lookupScript: string;
  readonly python: string;
  /** SQLite file backing the durable queue. */
  readonly dbPath: string;
  /** Worker poll interval (ms) when the queue is empty. */
  readonly pollIntervalMs: number;
  /** Per-lookup timeout (ms) — a lookup sleeps ~9s for paid content + vision. */
  readonly lookupTimeoutMs: number;
}

export function loadConfig(): ServiceConfig {
  const root = join(import.meta.dir, '..');
  return {
    port: Number(process.env['MRNUMBER_PORT'] ?? 8787),
    serviceToken: fileOrEnv(
      'MRNUMBER_SERVICE_TOKEN',
      join(homedir(), '.config/cocotte-secrets/mr-number.service-token'),
    ),
    lookupScript: process.env['MR_NUMBER_LOOKUP_SCRIPT'] ?? join(root, 'client', 'mr_lookup.py'),
    python: process.env['MR_NUMBER_PYTHON'] ?? '/opt/homebrew/bin/python3',
    dbPath: process.env['MRNUMBER_QUEUE_DB'] ?? join(root, 'service', 'queue.sqlite'),
    pollIntervalMs: Number(process.env['MRNUMBER_POLL_MS'] ?? 2000),
    lookupTimeoutMs: Number(process.env['MRNUMBER_LOOKUP_TIMEOUT_MS'] ?? 180_000),
  };
}