import { tap, expect } from '@git.zone/tstest/tapbundle';
import { SmartMigration, SmartMigrationError } from '../ts/index.js';

// Pure-logic tests for the SmartMigration constructor — no database required.

tap.test('constructor: rejects empty options', async () => {
  expect(() => new (SmartMigration as any)()).toThrow();
  expect(() => new (SmartMigration as any)(null)).toThrow();
});

tap.test('constructor: requires targetVersion', async () => {
  expect(() => new SmartMigration({} as any)).toThrow();
});

tap.test('constructor: rejects invalid targetVersion', async () => {
  let caught: SmartMigrationError | undefined;
  try {
    // not a real semver
    new SmartMigration({ targetVersion: 'not-a-version', db: {} as any });
  } catch (err) {
    caught = err as SmartMigrationError;
  }
  expect(caught).toBeInstanceOf(SmartMigrationError);
  expect(caught!.code).toEqual('INVALID_VERSION');
});

tap.test('constructor: rejects when neither db nor bucket given', async () => {
  let caught: SmartMigrationError | undefined;
  try {
    new SmartMigration({ targetVersion: '1.0.0' });
  } catch (err) {
    caught = err as SmartMigrationError;
  }
  expect(caught).toBeInstanceOf(SmartMigrationError);
  expect(caught!.code).toEqual('NO_RESOURCES');
});

tap.test('constructor: defaults ledgerBackend to "mongo" when db is given', async () => {
  const m = new SmartMigration({
    targetVersion: '1.0.0',
    db: {} as any,
  });
  expect(m.settings.ledgerBackend).toEqual('mongo');
  expect(m.settings.ledgerName).toEqual('smartmigration');
  expect(m.settings.lockWaitMs).toEqual(60_000);
  expect(m.settings.lockTtlMs).toEqual(600_000);
  expect(m.settings.dryRun).toBeFalse();
});

tap.test('constructor: defaults ledgerBackend to "s3" when only bucket is given', async () => {
  const m = new SmartMigration({
    targetVersion: '1.0.0',
    bucket: {} as any,
  });
  expect(m.settings.ledgerBackend).toEqual('s3');
});

tap.test('constructor: rejects mongo backend without db', async () => {
  let caught: SmartMigrationError | undefined;
  try {
    new SmartMigration({
      targetVersion: '1.0.0',
      bucket: {} as any,
      ledgerBackend: 'mongo',
    });
  } catch (err) {
    caught = err as SmartMigrationError;
  }
  expect(caught).toBeInstanceOf(SmartMigrationError);
  expect(caught!.code).toEqual('LEDGER_BACKEND_MISMATCH');
});

tap.test('constructor: rejects s3 backend without bucket', async () => {
  let caught: SmartMigrationError | undefined;
  try {
    new SmartMigration({
      targetVersion: '1.0.0',
      db: {} as any,
      ledgerBackend: 's3',
    });
  } catch (err) {
    caught = err as SmartMigrationError;
  }
  expect(caught).toBeInstanceOf(SmartMigrationError);
  expect(caught!.code).toEqual('LEDGER_BACKEND_MISMATCH');
});

tap.test('step(): rejects empty id', async () => {
  const m = new SmartMigration({ targetVersion: '1.0.0', db: {} as any });
  expect(() => m.step('')).toThrow();
});

export default tap.start();