Initial commit of Descrybe v2 without local scratch artifacts.

Drop one-shot tmp/axe scripts and agent i18n scratch so the Gitea tree is deployable.

apps/api/internal/i18n/locale.go

@@ -0,0 +1,125 @@
+package i18n
+
+import (
+	"context"
+	"strconv"
+	"strings"
+)
+
+// Default is the fallback UI/API locale when Accept-Language is missing or unsupported.
+const Default = "en"
+
+// Supported UI/API locales for public error/validation copy.
+// Keep aligned with apps/web/src/lib/i18n/locales.ts (UI_LOCALES).
+var Supported = []string{"en", "es", "fr", "de", "it", "pt", "nl", "pl", "ja"}
+
+var supportedSet map[string]struct{}
+
+func init() {
+	supportedSet = make(map[string]struct{}, len(Supported))
+	for _, code := range Supported {
+		supportedSet[code] = struct{}{}
+	}
+}
+
+type ctxKey struct{}
+
+// WithLocale stores a resolved locale on ctx.
+func WithLocale(ctx context.Context, locale string) context.Context {
+	return context.WithValue(ctx, ctxKey{}, Normalize(locale))
+}
+
+// FromContext returns the locale stored by middleware, or Default.
+func FromContext(ctx context.Context) string {
+	if ctx == nil {
+		return Default
+	}
+	if v, ok := ctx.Value(ctxKey{}).(string); ok && v != "" {
+		return v
+	}
+	return Default
+}
+
+// Normalize lowercases/trims and maps to a supported primary language tag, or Default.
+func Normalize(raw string) string {
+	code := strings.ToLower(strings.TrimSpace(raw))
+	if code == "" || code == "*" {
+		return Default
+	}
+	if i := strings.IndexByte(code, '-'); i > 0 {
+		code = code[:i]
+	}
+	if i := strings.IndexByte(code, '_'); i > 0 {
+		code = code[:i]
+	}
+	if _, ok := supportedSet[code]; ok {
+		return code
+	}
+	return Default
+}
+
+// IsSupported reports whether the primary language tag is in Supported.
+func IsSupported(raw string) bool {
+	code := strings.ToLower(strings.TrimSpace(raw))
+	if code == "" {
+		return false
+	}
+	if i := strings.IndexByte(code, '-'); i > 0 {
+		code = code[:i]
+	}
+	if i := strings.IndexByte(code, '_'); i > 0 {
+		code = code[:i]
+	}
+	_, ok := supportedSet[code]
+	return ok
+}
+
+// Resolve picks the best supported locale from an Accept-Language header value.
+// Quality values are respected; unsupported tags are skipped; empty → Default.
+func Resolve(acceptLanguage string) string {
+	header := strings.TrimSpace(acceptLanguage)
+	if header == "" {
+		return Default
+	}
+	bestTag := ""
+	bestQ := -1.0
+	for _, part := range strings.Split(header, ",") {
+		part = strings.TrimSpace(part)
+		if part == "" {
+			continue
+		}
+		tag := part
+		q := 1.0
+		if i := strings.IndexByte(part, ';'); i >= 0 {
+			tag = strings.TrimSpace(part[:i])
+			for _, p := range strings.Split(part[i+1:], ";") {
+				p = strings.TrimSpace(p)
+				if len(p) >= 2 && (p[0] == 'q' || p[0] == 'Q') && p[1] == '=' {
+					if parsed, err := strconv.ParseFloat(strings.TrimSpace(p[2:]), 64); err == nil {
+						q = parsed
+					}
+				}
+			}
+		}
+		primary := strings.ToLower(strings.TrimSpace(tag))
+		if primary == "*" {
+			if q > bestQ {
+				bestQ = q
+				bestTag = Default
+			}
+			continue
+		}
+		if !IsSupported(primary) {
+			continue
+		}
+		norm := Normalize(primary)
+		if q > bestQ {
+			bestQ = q
+			bestTag = norm
+		}
+	}
+	if bestTag == "" {
+		return Default
+	}
+	return bestTag
+}