import { Either } from '@emprespresso/pengueno';

describe('Either.retrying', () => {
    beforeEach(() => {
        jest.clearAllMocks();
    });

    test('succeeds on first attempt', async () => {
        const supplier = jest.fn().mockResolvedValue(Either.right<string, string>('success'));
        const interval = jest.fn().mockResolvedValue(undefined);

        const result = await Either.retrying(supplier, 3, interval);

        expect(result.right().get()).toBe('success');
        expect(supplier).toHaveBeenCalledTimes(1);
    });

    test('never succeeds after all attempts', async () => {
        const supplier = jest.fn().mockResolvedValue(Either.left<string, string>('failed'));
        const interval = jest.fn().mockResolvedValue(undefined);

        const result = await Either.retrying(supplier, 3, interval);

        expect(result.left().get()).toBe('failed');
        expect(supplier).toHaveBeenCalledTimes(3);
    });

    test('attempts correct number of times and calls interval with backoff', async () => {
        const supplier = jest.fn()
            .mockResolvedValueOnce(Either.left<string, string>('attempt 1 failed'))
            .mockResolvedValueOnce(Either.left<string, string>('attempt 2 failed'))
            .mockResolvedValueOnce(Either.right<string, string>('attempt 3 success'));

        const interval = jest.fn().mockResolvedValue(undefined);

        const result = await Either.retrying(supplier, 3, interval);

        expect(result.right().get()).toBe('attempt 3 success');
        expect(supplier).toHaveBeenCalledTimes(3);
        expect(interval).toHaveBeenCalledTimes(3);
        expect(interval).toHaveBeenNthCalledWith(1, 0);
        expect(interval).toHaveBeenNthCalledWith(2, 1);
        expect(interval).toHaveBeenNthCalledWith(3, 2);
    });
});