From 46f57800576a9c3c69e607ff6e8c340081bde110 Mon Sep 17 00:00:00 2001
From: m1ngsama <contact@m1ng.space>
Date: Sun, 24 May 2026 15:20:01 +0800
Subject: [PATCH] i18n: index text catalog by language

---
 docs/CHANGELOG.md      |  2 ++
 include/common.h       |  3 ++-
 src/i18n.c             |  2 ++
 src/i18n_text.c        | 17 ++++++++++-------
 tests/unit/test_i18n.c |  2 ++
 5 files changed, 18 insertions(+), 8 deletions(-)

diff --git a/docs/CHANGELOG.md b/docs/CHANGELOG.md
index f945963..82b42c4 100644
--- a/docs/CHANGELOG.md
+++ b/docs/CHANGELOG.md
@@ -52,6 +52,8 @@
   one internal language registry.
 - Removed the unused `MODE_HELP` enum value and refreshed development-guide
   module descriptions for the split between language parsing and text lookup.
+- `i18n_text` now indexes localized strings by `UI_LANG_*` instead of storing
+  English/Chinese as hard-coded struct fields.
 - Documented i18n and user-facing text rules for English-first source text,
   stable command syntax, concise help copy, and translation-only localization.
 
diff --git a/include/common.h b/include/common.h
index bbdff97..14ba70f 100644
--- a/include/common.h
+++ b/include/common.h
@@ -46,7 +46,8 @@ typedef enum {
 /* UI language */
 typedef enum {
     UI_LANG_EN,
-    UI_LANG_ZH
+    UI_LANG_ZH,
+    UI_LANG_COUNT
 } ui_lang_t;
 
 /* Runtime helpers */
diff --git a/src/i18n.c b/src/i18n.c
index 850d01f..8a06c4c 100644
--- a/src/i18n.c
+++ b/src/i18n.c
@@ -12,6 +12,8 @@ static const ui_lang_definition_t ui_lang_defs[] = {
     {UI_LANG_EN, "en", {"en", "c", "posix", NULL}},
     {UI_LANG_ZH, "zh", {"zh", NULL}}
 };
+typedef char ui_lang_defs_must_cover_enum[
+    sizeof(ui_lang_defs) / sizeof(ui_lang_defs[0]) == UI_LANG_COUNT ? 1 : -1];
 
 static const char *skip_space(const char *value) {
     while (value && *value &&
diff --git a/src/i18n_text.c b/src/i18n_text.c
index cfe5368..6221972 100644
--- a/src/i18n_text.c
+++ b/src/i18n_text.c
@@ -1,8 +1,7 @@
 #include "i18n.h"
 
 typedef struct {
-    const char *en;
-    const char *zh;
+    const char *text[UI_LANG_COUNT];
 } i18n_text_entry_t;
 
 static const i18n_text_entry_t text_catalog[I18N_TEXT_COUNT] = {
@@ -209,12 +208,16 @@ const char *i18n_text(ui_lang_t lang, i18n_text_id_t id) {
         return "";
     }
 
-    const i18n_text_entry_t *entry = &text_catalog[id];
-    if (lang == UI_LANG_ZH && entry->zh) {
-        return entry->zh;
+    if ((int)lang < 0 || lang >= UI_LANG_COUNT) {
+        lang = UI_LANG_EN;
     }
-    if (entry->en) {
-        return entry->en;
+
+    const i18n_text_entry_t *entry = &text_catalog[id];
+    if (entry->text[lang]) {
+        return entry->text[lang];
+    }
+    if (entry->text[UI_LANG_EN]) {
+        return entry->text[UI_LANG_EN];
     }
     return "";
 }
diff --git a/tests/unit/test_i18n.c b/tests/unit/test_i18n.c
index 5fa2a7d..4c0af8c 100644
--- a/tests/unit/test_i18n.c
+++ b/tests/unit/test_i18n.c
@@ -83,6 +83,8 @@ TEST(text_lookup_matches_language) {
                   "display name") != NULL);
     assert(strstr(i18n_text(UI_LANG_ZH, I18N_USERNAME_PROMPT),
                   "用户名") != NULL);
+    assert(strstr(i18n_text((ui_lang_t)99, I18N_USERNAME_PROMPT),
+                  "display name") != NULL);
     assert(strstr(i18n_text(UI_LANG_EN, I18N_WELCOME_SUBTITLE),
                   "anonymous chat") != NULL);
     assert(strstr(i18n_text(UI_LANG_ZH, I18N_WELCOME_SUBTITLE),