H-412: cover legacy widget attachment parity (#73)

Co-authored-by: Rogee <rogee@ipao.vip>

backend/internal/handler/widget/widget_handler_test.go

@@ -1933,7 +1933,7 @@ func TestWidgetHandler_ChatwootLabelsReturnNotFoundWithoutConversationContext(t
 
 func TestWidgetHandler_LegacySendMessageUsesWidgetPayload(t *testing.T) {
 	db, router, _ := setupWidgetHandlerTest(t)
-	_, _ = seedWidgetHandlerData(t, db)
+	account, _ := seedWidgetHandlerData(t, db)
 
 	// First init to get a widget_token
 	initBody := map[string]interface{}{
@@ -1971,19 +1971,46 @@ func TestWidgetHandler_LegacySendMessageUsesWidgetPayload(t *testing.T) {
 	require.NoError(t, db.First(&conversation).Error)
 	displayID := uint(42)
 	require.NoError(t, db.Model(&conversation).Update("display_id", displayID).Error)
+	upload := &model.DirectUpload{
+		UploadUUID:   "signed-legacy-widget-upload",
+		AccountID:    account.ID,
+		Status:       model.DirectUploadStatusPending,
+		Source:       model.DirectUploadSourceWidget,
+		OriginalName: "legacy.png",
+		FileType:     "image",
+		MimeType:     "image/png",
+		FileSize:     12,
+		FileURL:      "/uploads/widget_direct/signed-legacy-widget-upload.png",
+		ThumbURL:     "/uploads/widget_direct/signed-legacy-widget-upload.png",
+		ExpiresAt:    time.Now().Add(time.Hour),
+	}
+	require.NoError(t, db.Create(upload).Error)
+	body := &bytes.Buffer{}
+	writer := multipart.NewWriter(body)
+	require.NoError(t, writer.WriteField("content", "Hello from handler test!"))
+	require.NoError(t, writer.WriteField("message[attachments][]", upload.UploadUUID))
+	require.NoError(t, writer.Close())
 
 	w = httptest.NewRecorder()
-	req, _ = http.NewRequest("POST", "/widget/messages", bytes.NewReader(msgJSON))
-	req.Header.Set("Content-Type", "application/json")
+	req, _ = http.NewRequest("POST", "/widget/messages", body)
+	req.Header.Set("Content-Type", writer.FormDataContentType())
 	req.Header.Set("X-Widget-Token", widgetToken)
 	router.ServeHTTP(w, req)
 	require.Equal(t, http.StatusOK, w.Code)
 
 	var msgResp map[string]interface{}
 	require.NoError(t, json.Unmarshal(w.Body.Bytes(), &msgResp))
+	assertWidgetMessageFixtureShape(t, msgResp)
 	assert.Nil(t, msgResp["message"])
 	assert.Equal(t, float64(0), msgResp["message_type"])
 	assert.Equal(t, float64(displayID), msgResp["conversation_id"])
+	attachments := msgResp["attachments"].([]interface{})
+	require.Len(t, attachments, 1)
+	attachment := attachments[0].(map[string]interface{})
+	assertWidgetAttachmentFixtureShape(t, attachment)
+	assert.Equal(t, upload.FileURL, attachment["data_url"])
+	assert.Equal(t, "image", attachment["file_type"])
+	assert.Equal(t, float64(account.ID), attachment["account_id"])
 }
 
 func TestWidgetHandler_SendMessage_NoWidgetToken(t *testing.T) {