package i18n

// Stable machine codes that must never be translated when used as the JSON
// "error" / "code" field value. Clients branch on these exact strings.
var stableCodes = map[string]struct{}{
	"password_not_set":         {},
	"email_mismatch":           {},
	"maintenance":              {},
	"read_only":                {},
	"already_claimed":          {},
	"not_claimable":            {},
	"invalid_credentials":      {},
	"user_already_exists":      {},
	"password_too_short":       {},
	"register_fields_required": {},
}

// IsStableCode reports whether msg is a machine-stable error token.
func IsStableCode(msg string) bool {
	_, ok := stableCodes[msg]
	return ok
}

// T returns msg translated for locale. Missing entries fall back to English msg.
// Stable machine codes are returned unchanged.
func T(locale, msg string) string {
	if msg == "" || IsStableCode(msg) {
		return msg
	}
	lang := Normalize(locale)
	if lang == Default {
		return msg
	}
	if pack, ok := catalogs[lang]; ok {
		if translated, ok := pack[msg]; ok && translated != "" {
			return translated
		}
	}
	return msg
}

// catalogs maps locale → (English source message → translation).
// English is the identity key; add entries here when introducing new public copy.
var catalogs = map[string]map[string]string{
	"es": esMessages,
	"fr": frMessages,
	"de": deMessages,
	"it": itMessages,
	"pt": ptMessages,
	"nl": nlMessages,
	"pl": plMessages,
	"ja": jaMessages,
}