import { formatCurrency } from '../shared/utils/currency';

describe( 'formatCurrency', () => {
	// ---- Positive tests ----

	it( 'formats a GBP amount', () => {
		const result = formatCurrency( 9.99, 'GBP' );
		expect( result ).toContain( '9.99' );
	} );

	it( 'formats an EUR amount', () => {
		const result = formatCurrency( 12.5, 'EUR' );
		expect( result ).toContain( '12' );
	} );

	it( 'formats a USD amount', () => {
		const result = formatCurrency( 100, 'USD' );
		expect( result ).toContain( '100' );
	} );

	it( 'defaults to GBP when currency is omitted', () => {
		const result = formatCurrency( 5 );
		expect( result ).toContain( '5' );
	} );

	it( 'formats zero correctly', () => {
		const result = formatCurrency( 0, 'GBP' );
		expect( result ).toContain( '0' );
	} );

	// ---- Negative tests ----

	it( 'does not throw for an invalid currency code — falls back gracefully', () => {
		expect( () => formatCurrency( 5, 'NOTACURRENCY' ) ).not.toThrow();
	} );

	it( 'fallback result still contains the numeric amount', () => {
		const result = formatCurrency( 42.5, 'NOTACURRENCY' );
		expect( result ).toContain( '42' );
	} );
} );