import {toNullable} from 'fp-ts/lib/Option';
import {Account, SimpleBank} from './bank';
import {
  Gen,
  Property,
  choose,
  elements,
  forall,
  keyValueOf,
  mapOf,
  mapOf1,
  property,
} from './property';

const sampleAccounts: Account[] = [
  'FR12345678901234',
  'DE2345678901234',
  'IT34567890123412',
];

const genAccount: Gen<Account> = elements(sampleAccounts);

const genBalance: Gen<number> = choose(0, 1000000);

const genAccounts: Gen<Map<Account, number>> = mapOf1(genAccount, genBalance);

describe('Bank Simulator', () => {
  test('can retrieve balance given account exists', () => {
    const prop = forall(genAccounts, accounts => {
      const api = new SimpleBank(accounts);
      return property(keyValueOf(accounts), ([accountNr, bal]) => {
        const retrieved = toNullable(api.balance(accountNr));
        return retrieved == bal;
      });
    });

    const result = Property.run(prop);

    console.log(result);
    expect(result.result).toBe('OK');
  });
});