import { describe, it, expect } from 'vitest';
import { createCurr } from '@/glob/lib/curr_engine.ts';
import { createLing, p } from '@/ling/lib/engine.ts';
import type { CurrDefinition } from '../lib/curr_types.ts';

// =============================================================================
// FIXTURES
// =============================================================================

const ling = createLing({ common: { ok: { es: 'Aceptar', en: 'OK' } } } as const, 'es');

const definitions: Record<string, CurrDefinition> = {
    EUR: {
        symbol         : '€',
        code           : 'EUR',
        name           : p({ es: { one: 'euro',           other: 'euros'           }, en: { one: 'euro',         other: 'euros'         } }),
        conversionValue: 1,
    },
    USD: {
        symbol         : '$',
        code           : 'USD',
        name           : p({ es: { one: 'dólar',          other: 'dólares'         }, en: { one: 'dollar',       other: 'dollars'       } }),
        conversionValue: 1.08,
    },
    MXN: {
        symbol         : '$',
        code           : 'MXN',
        name           : p({ es: { one: 'peso mexicano',  other: 'pesos mexicanos' }, en: { one: 'Mexican peso', other: 'Mexican pesos' } }),
        conversionValue: 18.5,
    },
    GBP: {
        symbol         : '£',
        code           : 'GBP',
        name           : p({ es: { one: 'libra esterlina', other: 'libras esterlinas' }, en: { one: 'pound sterling', other: 'pounds sterling' } }),
        conversionValue: 0.85,
    },
    JPY: {
        symbol         : '¥',
        code           : 'JPY',
        name           : p({ es: { one: 'yen',            other: 'yenes'           }, en: { one: 'yen',          other: 'yen'           } }),
        conversionValue: null, // sin conversión disponible
    },
};

// =============================================================================
// CURR — Formato y conversión de moneda
// =============================================================================

describe('createCurr', () => {

    describe('selectedCurrency', () => {

        it('usa la primera moneda definida por defecto', () => {
            const curr = createCurr(definitions, ling, {}, 'es');
            expect(curr.getCurrency()).toBe('EUR');
        });

        it('acepta selectedCurrency en la configuración', () => {
            const curr = createCurr(definitions, ling, { selectedCurrency: 'MXN' }, 'es');
            expect(curr.getCurrency()).toBe('MXN');
        });

        it('setCurrency cambia la moneda activa', () => {
            const curr = createCurr(definitions, ling, { selectedCurrency: 'EUR' }, 'es');
            curr.setCurrency('USD');
            expect(curr.getCurrency()).toBe('USD');
        });

        it('setCurrency acepta minúsculas', () => {
            const curr = createCurr(definitions, ling, {}, 'es');
            curr.setCurrency('gbp');
            expect(curr.getCurrency()).toBe('GBP');
        });

    });

    describe('f() — display symbol (por defecto)', () => {

        it('formatea con símbolo en es', () => {
            const curr = createCurr(definitions, ling, { selectedCurrency: 'EUR' }, 'es');
            expect(curr.f(99.5)).toBe('99,50 €');
        });

        it('formatea con símbolo en en', () => {
            const curr = createCurr(definitions, ling, { selectedCurrency: 'EUR' }, 'en');
            expect(curr.f(99.5)).toBe('99.50 €');
        });

        it('usa selectedCurrency activa', () => {
            const curr = createCurr(definitions, ling, { selectedCurrency: 'EUR' }, 'es');
            curr.setCurrency('GBP');
            expect(curr.f(99.5)).toBe('99,50 £');
        });

    });

    describe('f() — display code', () => {

        it('formatea con código ISO', () => {
            const curr = createCurr(definitions, ling, { selectedCurrency: 'EUR' }, 'es');
            expect(curr.f(99.5, 'code')).toBe('99,50 EUR');
        });

    });

    describe('f() — display name (pluralización)', () => {

        it('singular en es', () => {
            const curr = createCurr(definitions, ling, { selectedCurrency: 'EUR' }, 'es');
            expect(curr.f(1, 'name')).toBe('1,00 euro');
        });

        it('plural en es', () => {
            const curr = createCurr(definitions, ling, { selectedCurrency: 'EUR' }, 'es');
            expect(curr.f(99.5, 'name')).toBe('99,50 euros');
        });

        it('singular en en', () => {
            const curr = createCurr(definitions, ling, { selectedCurrency: 'EUR' }, 'en');
            expect(curr.f(1, 'name')).toBe('1.00 euro');
        });

        it('plural MXN en es', () => {
            const curr = createCurr(definitions, ling, { selectedCurrency: 'MXN' }, 'es');
            expect(curr.f(2, 'name')).toBe('2,00 pesos mexicanos');
        });

    });

    describe('f() — locale reactivo via función', () => {

        it('responde a cambios de locale sin recrear el módulo', () => {
            let locale = 'es';
            const curr = createCurr(definitions, ling, { selectedCurrency: 'EUR' }, () => locale);

            expect(curr.f(99.5)).toContain(',50 €');

            locale = 'en';
            expect(curr.f(99.5)).toContain('.50 €');
        });

    });

    describe('f() — moneda no registrada', () => {

        it('fallback al código ISO si la moneda no está definida', () => {
            const curr = createCurr(definitions, ling, {}, 'es');
            curr.setCurrency('XXX');
            expect(curr.f(99.5)).toBe('99,50 XXX');
        });

    });

    describe('convert()', () => {

        it('convierte EUR a USD', () => {
            const curr = createCurr(definitions, ling, { selectedCurrency: 'EUR' }, 'es');
            expect(curr.convert(100, 'EUR', 'USD')).toBeCloseTo(108, 1);
        });

        it('convierte EUR a MXN', () => {
            const curr = createCurr(definitions, ling, { selectedCurrency: 'EUR' }, 'es');
            expect(curr.convert(100, 'EUR', 'MXN')).toBeCloseTo(1850, 0);
        });

        it('misma moneda devuelve el mismo valor', () => {
            const curr = createCurr(definitions, ling, { selectedCurrency: 'EUR' }, 'es');
            expect(curr.convert(100, 'EUR', 'EUR')).toBe(100);
        });

        it('devuelve null si conversionValue es null', () => {
            const curr = createCurr(definitions, ling, { selectedCurrency: 'EUR' }, 'es');
            expect(curr.convert(100, 'EUR', 'JPY')).toBeNull();
        });

        it('conversionValue como función dinámica', () => {
            let rate = 1.08;
            const defs = {
                EUR: { ...definitions.EUR },
                USD: { ...definitions.USD, conversionValue: () => rate },
            };
            const curr = createCurr(defs, ling, { selectedCurrency: 'EUR' }, 'es');

            expect(curr.convert(100, 'EUR', 'USD')).toBeCloseTo(108, 1);

            rate = 1.20;
            expect(curr.convert(100, 'EUR', 'USD')).toBeCloseTo(120, 1);
        });

    });

    describe('convertTo()', () => {

        it('convierte desde selectedCurrency a otra moneda', () => {
            const curr = createCurr(definitions, ling, { selectedCurrency: 'EUR' }, 'es');
            expect(curr.convertTo(100, 'USD')).toBeCloseTo(108, 1);
        });

        it('respeta la moneda activa cambiada con setCurrency', () => {
            const curr = createCurr(definitions, ling, { selectedCurrency: 'EUR' }, 'es');
            curr.setCurrency('USD');
            expect(curr.convertTo(108, 'EUR')).toBeCloseTo(100, 1);
        });

    });

    describe('get()', () => {

        it('devuelve la definición de una moneda registrada', () => {
            const curr = createCurr(definitions, ling, {}, 'es');
            expect(curr.get('EUR')?.symbol).toBe('€');
        });

        it('devuelve undefined para moneda no registrada', () => {
            const curr = createCurr(definitions, ling, {}, 'es');
            expect(curr.get('XXX')).toBeUndefined();
        });

        it('acepta minúsculas', () => {
            const curr = createCurr(definitions, ling, {}, 'es');
            expect(curr.get('eur')).toBeDefined();
        });

    });

});