From 60a9b5a693a76ba07049b03c70e81355fca51d52 Mon Sep 17 00:00:00 2001
From: Joseph Garrone <joseph.garrone.gj@gmail.com>
Date: Fri, 6 Dec 2024 00:38:09 +0100
Subject: [PATCH] Improve i18n api typing

---
 .../src/multi-page/i18n.ts                    |  8 +--
 src/login/i18n/withJsx/i18nBuilder.ts         |  2 +-
 test/login/i18n.typelevel-spec.ts             | 62 +++++++++++++++++++
 3 files changed, 66 insertions(+), 6 deletions(-)

diff --git a/src/bin/initialize-account-theme/src/multi-page/i18n.ts b/src/bin/initialize-account-theme/src/multi-page/i18n.ts
index 49062b8c..6dc2d03a 100644
--- a/src/bin/initialize-account-theme/src/multi-page/i18n.ts
+++ b/src/bin/initialize-account-theme/src/multi-page/i18n.ts
@@ -1,11 +1,9 @@
 import { i18nBuilder } from "keycloakify/account";
 import type { ThemeName } from "../kc.gen";
 
-const { useI18n, ofTypeI18n } = i18nBuilder
-    .withThemeName<ThemeName>()
-    .withExtraLanguages({})
-    .withCustomTranslations({})
-    .build();
+/** @see: https://docs.keycloakify.dev/i18n */
+// eslint-disable-next-line @typescript-eslint/no-unused-vars
+const { useI18n, ofTypeI18n } = i18nBuilder.withThemeName<ThemeName>().build();
 
 type I18n = typeof ofTypeI18n;
 
diff --git a/src/login/i18n/withJsx/i18nBuilder.ts b/src/login/i18n/withJsx/i18nBuilder.ts
index 9ec3c873..f3e9ce5f 100644
--- a/src/login/i18n/withJsx/i18nBuilder.ts
+++ b/src/login/i18n/withJsx/i18nBuilder.ts
@@ -46,7 +46,7 @@ export type I18nBuilder<
             }>
         ) => I18nBuilder<
             ThemeName,
-            MessageKey_themeDefined,
+            string extends MessageKey_themeDefined ? never : MessageKey_themeDefined,
             LanguageTag_notInDefaultSet,
             ExcludedMethod | "withCustomTranslations"
         >;
diff --git a/test/login/i18n.typelevel-spec.ts b/test/login/i18n.typelevel-spec.ts
index bfd0a5d5..af1ebc9a 100644
--- a/test/login/i18n.typelevel-spec.ts
+++ b/test/login/i18n.typelevel-spec.ts
@@ -62,3 +62,65 @@ type I18n = typeof ofTypeI18n;
 
     assert<Equals<typeof node, JSX.Element>>;
 }
+
+{
+    const i18n = Reflect<I18n>();
+
+    i18n.msg("passwordConfirm");
+}
+
+{
+    const i18n = Reflect<I18n>();
+
+    // @ts-expect-error
+    i18n.msg("iDoNotExist");
+}
+
+{
+    const { ofTypeI18n } = i18nBuilder
+        .withThemeName<"keycloakify-starter">()
+        .withCustomTranslations({})
+        .build();
+
+    type I18n = typeof ofTypeI18n;
+
+    {
+        const i18n = Reflect<I18n>();
+
+        // @ts-expect-error
+        const node = i18n.msg("iDoNotExist");
+
+        assert<Equals<typeof node, JSX.Element>>;
+    }
+}
+
+i18nBuilder.withThemeName<"my-theme-1" | "my-theme-2">().withCustomTranslations({
+    en: {
+        myCustomKey1: "my-custom-key-1-en",
+        // @ts-expect-error
+        myCustomKey2: {
+            "my-theme-1": "my-theme-1-en"
+            //"my-theme-2": "my-theme-2-en"
+        }
+    }
+});
+
+i18nBuilder
+    .withThemeName<"my-theme-1" | "my-theme-2">()
+    .withExtraLanguages({
+        he: {
+            label: "עברית",
+            getMessages: () => import("./he")
+        }
+    })
+    .withCustomTranslations({
+        en: {
+            myCustomKey1: "my-custom-key-1-en",
+            myCustomKey2: "my-custom-key-2-en"
+        },
+        // @ts-expect-error
+        he: {
+            myCustomKey1: "my-custom-key-1-he"
+            //myCustomKey2: "my-custom-key-2-he"
+        }
+    });