import { describe, it, expect } from 'vitest';
import { generateI18nFile } from './language-config';

describe('generateI18nFile', () => {
  it('guards the i18next singleton with isInitialized before calling .init()', () => {
    const output = generateI18nFile(['pt-BR', 'en', 'es']);

    expect(output).toContain('if (!i18n.isInitialized) {');
    expect(output).toMatch(/}\s*else\s*{/);
  });

  it('merges default resources via addResourceBundle with deep merge and no overwrite', () => {
    const output = generateI18nFile(['pt-BR', 'en', 'es']);

    expect(output).toContain(
      "i18n.addResourceBundle(lang, 'translation', resources, true, false);"
    );
  });

  it('builds a defaultResourcesByLang map covering every selected language', () => {
    const output = generateI18nFile(['pt-BR', 'en']);

    expect(output).toContain('const defaultResourcesByLang');
    expect(output).toContain("'pt-BR': ptBR,");
    expect(output).toContain('en,');
    expect(output).not.toContain("'es': es,");
  });

  it('throws when no languages are selected', () => {
    expect(() => generateI18nFile([])).toThrow(/must include at least one language/);
  });
});