feat: translation middleware

internal/components/translate/context.go

@@ -0,0 +1,81 @@
+package translate
+
+import (
+	"context"
+	"log/slog"
+	"path"
+)
+
+type contextKey string
+
+const (
+	serviceKey contextKey = "translationService"
+	langKey    contextKey = "language"
+)
+
+func Language(ctx context.Context) string {
+	lang, ok := ctx.Value(langKey).(string)
+	if !ok {
+		return ""
+	}
+	return lang
+}
+
+func SupportedLanguages(ctx context.Context) []string {
+	s, ok := ctx.Value(serviceKey).(*Service)
+	if !ok {
+		slog.Error("could not extract translation service from context for getting supported languages")
+	}
+	return s.SupportedLanguages()
+}
+
+func T(ctx context.Context, key string) string {
+	s, ok := ctx.Value(serviceKey).(*Service)
+	if !ok {
+		slog.Error("could not extract translation service from context", "ctx", ctx, "key", key)
+		return key
+	}
+
+	lang := Language(ctx)
+
+	translation, ok := s.translations[lang][key]
+	if !ok {
+		slog.Warn("could not translate", "key", key, "language", lang)
+		return key
+	}
+
+	return translation
+}
+
+func Path(ctx context.Context, pp ...string) string {
+	return PathForLang(ctx, Language(ctx), pp...)
+}
+
+func PathForLang(ctx context.Context, lang string, pp ...string) string {
+	slog.Info("path for lang", "path", pp)
+	s, ok := ctx.Value(serviceKey).(*Service)
+	if !ok {
+		slog.Error("could not extract translation service from context for translating path", "ctx", ctx, "path", pp)
+		return path.Join(pp...)
+	}
+
+	if len(pp) > 0 {
+		if _, ok := s.translations[pp[0]]; ok {
+			pp = pp[1:]
+		}
+	}
+
+	return path.Join(append([]string{lang}, pp...)...)
+}
+
+func (s *Service) SupportedLanguages() (languages []string) {
+	for lang := range s.translations {
+		languages = append(languages, lang)
+	}
+
+	return
+}
+
+func (s *Service) DefaultLanguage() string {
+	return s.defaultLanguage
+}