import { deriveEventState, endAfterStartValidator, toDatetimeLocal, toIsoUtc } from '../../frontend/src/app/features/admin/general.pure';

describe('deriveEventState', () => {
  const start = '2026-01-01T00:00:00Z';
  const end = '2026-01-02T00:00:00Z';

  it('returns "unconfigured" when start or end is missing', () => {
    expect(deriveEventState('', '')).toBe('unconfigured');
    expect(deriveEventState(start, '')).toBe('unconfigured');
    expect(deriveEventState('', end)).toBe('unconfigured');
  });

  it('returns "unconfigured" when dates cannot be parsed', () => {
    expect(deriveEventState('not-a-date', end)).toBe('unconfigured');
  });

  it('returns "countdown" when now is before start', () => {
    const s = new Date(Date.now() + 60_000).toISOString();
    const e = new Date(Date.now() + 120_000).toISOString();
    expect(deriveEventState(s, e)).toBe('countdown');
  });

  it('returns "running" when now is between start and end', () => {
    const s = new Date(Date.now() - 60_000).toISOString();
    const e = new Date(Date.now() + 60_000).toISOString();
    expect(deriveEventState(s, e)).toBe('running');
  });

  it('returns "stopped" when now is after end', () => {
    const s = new Date(Date.now() - 120_000).toISOString();
    const e = new Date(Date.now() - 60_000).toISOString();
    expect(deriveEventState(s, e)).toBe('stopped');
  });
});

describe('endAfterStartValidator', () => {
  const ctrl = (start: string, end: string) => ({
    get: (k: string) =>
      k === 'eventStartUtc'
        ? { value: start }
        : k === 'eventEndUtc'
        ? { value: end }
        : { value: '' },
  });

  it('returns null when either field is empty', () => {
    expect(endAfterStartValidator(ctrl('', '2026-01-01T00:00:00Z'))).toBeNull();
    expect(endAfterStartValidator(ctrl('2026-01-01T00:00:00Z', ''))).toBeNull();
  });

  it('returns null when end is strictly after start', () => {
    expect(endAfterStartValidator(ctrl('2026-01-01T00:00:00Z', '2026-01-02T00:00:00Z'))).toBeNull();
  });

  it('returns { endBeforeStart: true } when end equals start', () => {
    expect(endAfterStartValidator(ctrl('2026-01-01T00:00:00Z', '2026-01-01T00:00:00Z'))).toEqual({ endBeforeStart: true });
  });

  it('returns { endBeforeStart: true } when end is before start', () => {
    expect(endAfterStartValidator(ctrl('2026-01-02T00:00:00Z', '2026-01-01T00:00:00Z'))).toEqual({ endBeforeStart: true });
  });
});

describe('datetime helpers', () => {
  it('toDatetimeLocal formats an ISO timestamp with UTC components', () => {
    expect(toDatetimeLocal('2026-01-02T03:04:00Z')).toBe('2026-01-02T03:04');
  });

  it('toDatetimeLocal returns empty string for invalid input', () => {
    expect(toDatetimeLocal('')).toBe('');
    expect(toDatetimeLocal('garbage')).toBe('');
  });

  it('toIsoUtc converts a local datetime back to UTC ISO', () => {
    const iso = toIsoUtc('2026-01-02T03:04');
    expect(iso).toMatch(/^2026-01-02T03:04:00\.000Z$/);
  });

  it('toIsoUtc returns input verbatim when empty', () => {
    expect(toIsoUtc('')).toBe('');
  });
});