deepl.go

package translate

import (
	"encoding/json"
	"errors"
	"fmt"
	"io"
	"net/http"
	"net/url"
	"os"
	"strings"
)

// translateTexts sendet einen Batch-Request an die DEEPL API, um alle übergebenen Texte in die Zielsprache zu übersetzen.
func translateTextsDeepl(texts []string, targetLang string) (map[string]string, error) {
	apiKey := os.Getenv("DEEPL_API_KEY")
	if apiKey == "" {
		return nil, errors.New("Missing DEEPL_API_KEY environment variable")
	}

	endpoint := "https://api.deepl.com/v2/translate"
	form := url.Values{}
	form.Set("auth_key", apiKey)
	form.Set("target_lang", strings.ToUpper(targetLang)) // DEEPL erwartet Großbuchstaben

	for _, text := range texts {
		form.Add("text", text)
	}

	resp, err := http.PostForm(endpoint, form)
	if err != nil {
		return nil, err
	}
	defer resp.Body.Close()

	if resp.StatusCode != http.StatusOK {
		body, _ := io.ReadAll(resp.Body)
		return nil, fmt.Errorf("DEEPL API returned status %d: %s", resp.StatusCode, body)
	}

	// Antwort-JSON dekodieren
	var deeplResp struct {
		Translations []struct {
			DetectedSourceLanguage string `json:"detected_source_language"`
			Text                   string `json:"text"`
		} `json:"translations"`
	}

	if err := json.NewDecoder(resp.Body).Decode(&deeplResp); err != nil {
		return nil, err
	}

	if len(deeplResp.Translations) != len(texts) {
		return nil, fmt.Errorf("DEEPL API returned %d translations, expected %d", len(deeplResp.Translations), len(texts))
	}

	result := make(map[string]string)
	for i, orig := range texts {
		result[orig] = deeplResp.Translations[i].Text
	}
	return result, nil
}