From 91f9bd944210afe4d6869cae3c6c20d8db0bf3c7 Mon Sep 17 00:00:00 2001
From: Alex Gleason <alex@alexgleason.me>
Date: Thu, 20 Feb 2025 11:04:41 -0600
Subject: [PATCH] Add mock LibreTranslate tests

---
 .../LibreTranslateTranslator.test.ts          | 68 ++++++++++++++-----
 .../translators/LibreTranslateTranslator.ts   | 25 +++++--
 2 files changed, 71 insertions(+), 22 deletions(-)

diff --git a/packages/translators/LibreTranslateTranslator.test.ts b/packages/translators/LibreTranslateTranslator.test.ts
index ca8c1d79..94da0ec0 100644
--- a/packages/translators/LibreTranslateTranslator.test.ts
+++ b/packages/translators/LibreTranslateTranslator.test.ts
@@ -1,21 +1,10 @@
-import { DittoConf } from '@ditto/conf';
 import { detectLanguage } from '@ditto/lang';
 import { assertEquals } from '@std/assert';
 
 import { LibreTranslateTranslator } from './LibreTranslateTranslator.ts';
 
-const {
-  libretranslateBaseUrl: baseUrl,
-  libretranslateApiKey: apiKey,
-  translationProvider,
-} = new DittoConf(Deno.env);
-
-const libretranslate = 'libretranslate';
-
-Deno.test('LibreTranslate translation with source language omitted', {
-  ignore: !(translationProvider === libretranslate && apiKey),
-}, async () => {
-  const translator = new LibreTranslateTranslator({ fetch: fetch, baseUrl, apiKey: apiKey! });
+Deno.test('LibreTranslate translation with source language omitted', async () => {
+  const translator = mockLibreTranslate();
 
   const data = await translator.translate(
     [
@@ -33,10 +22,8 @@ Deno.test('LibreTranslate translation with source language omitted', {
   assertEquals(detectLanguage(data.results[2], 0), 'ca');
 });
 
-Deno.test('LibreTranslate translation with source language set', {
-  ignore: !(translationProvider === libretranslate && apiKey),
-}, async () => {
-  const translator = new LibreTranslateTranslator({ fetch: fetch, baseUrl, apiKey: apiKey! });
+Deno.test('LibreTranslate translation with source language set', async () => {
+  const translator = mockLibreTranslate();
 
   const data = await translator.translate(
     [
@@ -53,3 +40,50 @@ Deno.test('LibreTranslate translation with source language set', {
   assertEquals(detectLanguage(data.results[1], 0), 'ca');
   assertEquals(detectLanguage(data.results[2], 0), 'ca');
 });
+
+function mockLibreTranslate(): LibreTranslateTranslator {
+  return new LibreTranslateTranslator({
+    apiKey: 'libretranslate',
+    fetch: async (input, init) => {
+      const req = new Request(input, init);
+      const body = await req.json();
+
+      switch (body.q) {
+        case 'Bom dia amigos':
+          return jsonResponse({
+            detectedLanguage: { language: 'pt' },
+            translatedText: 'Bon dia, amics.',
+          });
+        case 'Meu nome é Patrick, um nome belo ou feio? A questão é mais profunda do que parece.':
+          return jsonResponse({
+            detectedLanguage: { language: 'pt' },
+            translatedText: 'Em dic Patrick, un nom molt o lleig? La pregunta és més profunda del que sembla.',
+          });
+        case 'A respiração é mais importante do que comer e tomar agua.':
+          return jsonResponse({
+            detectedLanguage: { language: 'pt' },
+            translatedText: 'La respiració és més important que menjar i prendre aigua.',
+          });
+      }
+
+      return new Response(JSON.stringify({ error: 'Not found' }), { status: 404 });
+    },
+  });
+}
+
+interface LibreTranslateResponse {
+  translatedText: string;
+  detectedLanguage?: {
+    language: string;
+  };
+}
+
+function jsonResponse(json: LibreTranslateResponse): Response {
+  const body = JSON.stringify(json);
+
+  return new Response(body, {
+    headers: {
+      'Content-Type': 'application/json',
+    },
+  });
+}
diff --git a/packages/translators/LibreTranslateTranslator.ts b/packages/translators/LibreTranslateTranslator.ts
index a8145223..cc978e90 100644
--- a/packages/translators/LibreTranslateTranslator.ts
+++ b/packages/translators/LibreTranslateTranslator.ts
@@ -71,12 +71,20 @@ export class LibreTranslateTranslator implements DittoTranslator {
 
     const response = await this.fetch(request);
     const json = await response.json();
-    if (!response.ok) {
-      throw new Error(json['error']);
-    }
-    const data = LibreTranslateTranslator.schema().parse(json);
 
-    return data;
+    console.log(json);
+
+    if (!response.ok) {
+      const result = LibreTranslateTranslator.errorSchema().safeParse(json);
+
+      if (result.success) {
+        throw new Error(result.data.error);
+      } else {
+        throw new Error(`Unexpected LibreTranslate error: ${response.statusText} (${response.status})`);
+      }
+    }
+
+    return LibreTranslateTranslator.schema().parse(json);
   }
 
   /** Libretranslate response schema.
@@ -90,4 +98,11 @@ export class LibreTranslateTranslator implements DittoTranslator {
       }).optional(),
     });
   }
+
+  /** Libretranslate error response schema. */
+  private static errorSchema() {
+    return z.object({
+      error: z.string(),
+    });
+  }
 }