import { describe, expect, it } from 'vitest';
import { createActiveFormat, createEngineFormat } from '..';

describe('createEngineFormat()', () => {
	it('composes number, currency, units and dates format engines', async () => {
		const formats = createEngineFormat({
			locale: 'en-US',
			currency: {
				rates: undefined
			}
		});

		expect(formats.getLocale()).toBe('en-US');
		expect(formats.numbers.format(1234.5)).toBe('1,234.5');
		expect(formats.currency.getCurrency()).toBe('USD');
		expect(formats.units.getSystem()).toBe('imperial');
		expect(formats.units.getDefaultUnit('distance')).toBe('mile');
		expect(formats.dates.getHourCycle()).toBe(12);

		formats.setLocale('es-ES');

		expect(formats.getLocale()).toBe('es-ES');
		expect(formats.currency.getCurrency()).toBe('EUR');
		expect(formats.units.getSystem()).toBe('metric');
		expect(formats.units.getDefaultUnit('distance')).toBe('kilometer');
		await expect(formats.currency.convert(1, 'EUR')).resolves.toBe(1);
	});
});

describe('createActiveFormat()', () => {
	it('fans out locale changes to every active format module', () => {
		const formats = createActiveFormat({ locale: 'en-US' });

		expect(formats.getLocale()).toBe('en-US');
		expect(formats.currency.getCurrency()).toBe('USD');
		expect(formats.units.getSystem()).toBe('imperial');
		expect(formats.dates.getHourCycle()).toBe(12);

		formats.setLocale('es-ES');

		expect(formats.getLocale()).toBe('es-ES');
		expect(formats.currency.getCurrency()).toBe('EUR');
		expect(formats.units.getSystem()).toBe('metric');
		expect(formats.dates.getDateOrder()).toBe('DMY');

		formats.dispose();
	});

	it('exposes disposed flag, is idempotent, and ignores setLocale post-dispose', () => {
		const formats = createActiveFormat({ locale: 'en-US' });

		expect(formats.disposed).toBe(false);
		formats.dispose();
		expect(formats.disposed).toBe(true);

		expect(() => formats.dispose()).not.toThrow();

		// setLocale is a silent no-op after dispose; the cached values stay
		// frozen at the last set value.
		const lastLocale = formats.getLocale();
		formats.setLocale('fr-FR');
		expect(formats.getLocale()).toBe(lastLocale);
	});
});