const path = require("node:path");

const ONE_DAY_SECONDS = 24 * 60 * 60;

function requiredEnv(name) {
  const value = process.env[name];
  if (!value) {
    throw new Error(`Missing required env: ${name}`);
  }
  return value;
}

function getConfig() {
  const nodeEnv = process.env.NODE_ENV ?? "development";
  const serverRoot = path.resolve(__dirname, "..");
  const storageDir = process.env.STORAGE_DIR ?? "generated/storage";

  return {
    nodeEnv,
    port: Number(process.env.PORT ?? 3000),
    host: process.env.HOST ?? "0.0.0.0",

    appOrigin: process.env.APP_ORIGIN ?? "",
    jwtSecret: requiredEnv("JWT_SECRET"),

    accessTokenTtl: "15m",
    refreshTtlSeconds: 7 * ONE_DAY_SECONDS,

    refreshCookieName: "refresh_token",
    cookieSecure:
      process.env.COOKIE_SECURE != null
        ? process.env.COOKIE_SECURE === "true"
        : nodeEnv === "production",

    passwordResetCodeTtlSeconds: Number(
      process.env.PASSWORD_RESET_CODE_TTL_SECONDS ?? 10 * 60,
    ),

    devShowPasswordResetCode: process.env.DEV_SHOW_PASSWORD_RESET_CODE === "true",

    appTimezone: process.env.APP_TIMEZONE ?? "Asia/Shanghai",
    storageDir: path.resolve(serverRoot, storageDir),
    signedUrlTtlSeconds: Number(process.env.SIGNED_URL_TTL_SECONDS ?? 600),
    maxUploadSizeBytes: Number(process.env.MAX_UPLOAD_SIZE_BYTES ?? 10 * 1024 * 1024),

    rateLimitEnabled:
      process.env.RATE_LIMIT_ENABLED != null
        ? process.env.RATE_LIMIT_ENABLED === "true"
        : nodeEnv === "production",
    rateLimitLoginMax: Number(process.env.RATE_LIMIT_LOGIN_MAX ?? 10),
    rateLimitLoginWindow: process.env.RATE_LIMIT_LOGIN_WINDOW ?? "1 minute",

    delegationRevokeCron: process.env.DELEGATION_REVOKE_CRON ?? "0 * * * *",

    ocrProvider: process.env.OCR_PROVIDER ?? "off",
    ocrBatchSize: Number(process.env.OCR_BATCH_SIZE ?? 10),
    ocrLockTtlSeconds: Number(process.env.OCR_LOCK_TTL_SECONDS ?? 300),
    ocrPollCron: process.env.OCR_POLL_CRON ?? "* * * * *",
    ocrMaxAttempts: Number(process.env.OCR_MAX_ATTEMPTS ?? 3),
    ocrTimeoutMs: Number(process.env.OCR_TIMEOUT_MS ?? 5000),

    tencentSecretId: process.env.TENCENT_SECRET_ID ?? "",
    tencentSecretKey: process.env.TENCENT_SECRET_KEY ?? "",
    tencentOcrRegion: process.env.TENCENT_OCR_REGION ?? "ap-beijing",
  };
}

module.exports = { getConfig };