vt-social/spec/lib/translation_service/libre_translate_spec.rb

# frozen_string_literal: true

require 'rails_helper'

RSpec.describe TranslationService::LibreTranslate do
  subject(:service) { described_class.new('https://libretranslate.example.com', 'my-api-key') }

  before do
    stub_request(:get, 'https://libretranslate.example.com/languages').to_return(
      body: '[{"code": "en","name": "English","targets": ["de","en","es"]},{"code": "da","name": "Danish","targets": ["en","pt"]}]'
    )
  end

  describe '#languages' do
    subject(:languages) { service.languages }

    it 'returns source languages' do
      expect(languages.keys).to eq ['en', 'da', nil]
    end

    it 'returns target languages for each source language' do
      expect(languages['en']).to eq %w(de es)
      expect(languages['da']).to eq %w(en pt)
    end

    it 'returns target languages for auto-detected language' do
      expect(languages[nil]).to eq %w(de en es pt)
    end
  end

  describe '#translate' do
    it 'returns translation with specified source language' do
      stub_request(:post, 'https://libretranslate.example.com/translate')
        .with(body: '{"q":["Hasta la vista"],"source":"es","target":"en","format":"html","api_key":"my-api-key"}')
        .to_return(body: '{"translatedText": ["See you"]}')

      translations = service.translate(['Hasta la vista'], 'es', 'en')
      expect(translations.size).to eq 1

      translation = translations.first
      expect(translation.detected_source_language).to be 'es'
      expect(translation.provider).to eq 'LibreTranslate'
      expect(translation.text).to eq 'See you'
    end

    it 'returns translation with auto-detected source language' do
      stub_request(:post, 'https://libretranslate.example.com/translate')
        .with(body: '{"q":["Guten Morgen"],"source":"auto","target":"en","format":"html","api_key":"my-api-key"}')
        .to_return(body: '{"detectedLanguage": [{"confidence": 92, "language": "de"}], "translatedText": ["Good morning"]}')

      translations = service.translate(['Guten Morgen'], nil, 'en')
      expect(translations.size).to eq 1

      translation = translations.first
      expect(translation.detected_source_language).to eq 'de'
      expect(translation.provider).to eq 'LibreTranslate'
      expect(translation.text).to eq 'Good morning'
    end

    it 'returns translation of multiple texts' do
      stub_request(:post, 'https://libretranslate.example.com/translate')
        .with(body: '{"q":["Guten Morgen","Gute Nacht"],"source":"de","target":"en","format":"html","api_key":"my-api-key"}')
        .to_return(body: '{"translatedText": ["Good morning", "Good night"]}')

      translations = service.translate(['Guten Morgen', 'Gute Nacht'], 'de', 'en')
      expect(translations.size).to eq 2

      expect(translations.first.text).to eq 'Good morning'
      expect(translations.last.text).to eq 'Good night'
    end
  end
end