refactor(common): decouple ConfigHttpServer from Swing dialogs

src/main/java/core/packetproxy/common/ConfigHttpServer.java

@@ -6,17 +6,20 @@
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
-import javax.swing.*;
-import packetproxy.gui.GUIMain;
 import packetproxy.model.*;
 
 public class ConfigHttpServer extends NanoHTTPD {
 
 	private final String allowedAccessToken;
+	private final ConfigHttpUiActions uiActions;
+	private final ConfigSettingsWriter settingsWriter;
 
-	public ConfigHttpServer(String hostname, int port, String allowedAccessToken) {
+	public ConfigHttpServer(String hostname, int port, String allowedAccessToken, ConfigHttpUiActions uiActions,
+			ConfigSettingsWriter settingsWriter) {
 		super(hostname, port);
 		this.allowedAccessToken = allowedAccessToken;
+		this.uiActions = uiActions;
+		this.settingsWriter = settingsWriter;
 	}
 
 	private void fixUpServerList(Map<Integer, Integer> serverMap, List<Server> serverList) {
@@ -117,18 +120,7 @@ public Response serve(IHTTPSession session) {
 
 			try {
 
-				GUIMain.getInstance().setAlwaysOnTop(true);
-				GUIMain.getInstance().setVisible(true);
-
-				GUIMain.getInstance().getTabbedPane().setSelectedIndex(GUIMain.Panes.OPTIONS.ordinal());
-
-				int option = JOptionPane.showConfirmDialog(GUIMain.getInstance(),
-						I18nString.get("Do you want to overwrite config?"), I18nString.get("Loading config"),
-						JOptionPane.YES_NO_OPTION, JOptionPane.WARNING_MESSAGE);
-
-				GUIMain.getInstance().setAlwaysOnTop(false);
-
-				if (option != JOptionPane.YES_OPTION) {
+				if (!uiActions.confirmOverwriteConfig()) {
 
 					return NanoHTTPD.newFixedLengthResponse(Response.Status.UNAUTHORIZED, MIME_HTML, null);
 				}
@@ -137,26 +129,7 @@ public Response serve(IHTTPSession session) {
 				session.parseBody(map);
 				String json = map.get("postData");
 
-				ConfigDaoHub daoHub = new Gson().fromJson(json, ConfigDaoHub.class);
-
-				Database.getInstance().dropConfigs();
-
-				for (ListenPort listenPort : daoHub.listenPortList) {
-
-					ListenPorts.getInstance().create(listenPort);
-				}
-				for (Server server : daoHub.serverList) {
-
-					Servers.getInstance().create(server);
-				}
-				for (Modification mod : daoHub.modificationList) {
-
-					Modifications.getInstance().create(mod);
-				}
-				for (SSLPassThrough passThrough : daoHub.sslPassThroughList) {
-
-					SSLPassThroughs.getInstance().create(passThrough);
-				}
+				settingsWriter.applyFromJson(json);
 
 				Response res = NanoHTTPD.newFixedLengthResponse(Response.Status.OK, "application/json",
 						"{\"status\": \"ok\"}");

src/main/java/core/packetproxy/common/ConfigHttpUiActions.java

@@ -0,0 +1,27 @@
+/*
+ * Copyright 2026 DeNA Co., Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package packetproxy.common;
+
+/** リモート設定 HTTP API から必要な GUI 操作。 */
+public interface ConfigHttpUiActions {
+
+	/**
+	 * 設定タブを表示し、設定を上書きしてよいかユーザーに確認する。
+	 *
+	 * @return 上書きを許可する場合 true
+	 */
+	boolean confirmOverwriteConfig();
+}

src/main/java/core/packetproxy/common/ConfigSettingsWriter.java

@@ -0,0 +1,46 @@
+/*
+ * Copyright 2026 DeNA Co., Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package packetproxy.common;
+
+import com.google.gson.Gson;
+import packetproxy.model.*;
+
+/** リモート設定 JSON を DB に反映する。 */
+public class ConfigSettingsWriter {
+
+	public void applyFromJson(String json) throws Exception {
+		var daoHub = new Gson().fromJson(json, ConfigDaoHub.class);
+
+		Database.getInstance().dropConfigs();
+
+		for (ListenPort listenPort : daoHub.listenPortList) {
+
+			ListenPorts.getInstance().create(listenPort);
+		}
+		for (Server server : daoHub.serverList) {
+
+			Servers.getInstance().create(server);
+		}
+		for (Modification mod : daoHub.modificationList) {
+
+			Modifications.getInstance().create(mod);
+		}
+		for (SSLPassThrough passThrough : daoHub.sslPassThroughList) {
+
+			SSLPassThroughs.getInstance().create(passThrough);
+		}
+	}
+}

src/main/java/core/packetproxy/gui/GUIOptionHubServer.java

@@ -11,6 +11,7 @@
 import javax.swing.*;
 import org.apache.commons.lang3.RandomStringUtils;
 import packetproxy.common.ConfigHttpServer;
+import packetproxy.common.ConfigSettingsWriter;
 import packetproxy.common.I18nString;
 import packetproxy.model.ConfigBoolean;
 import packetproxy.model.ConfigString;
@@ -104,7 +105,8 @@ private void stopServer() {
 
 	private void startServer() throws Exception {
 		String accessToken = new ConfigString("SharingConfigsAccessToken").getString();
-		this.server = new ConfigHttpServer("localhost", 32349, accessToken);
+		this.server = new ConfigHttpServer("localhost", 32349, accessToken, new SwingConfigHttpUiActions(),
+				new ConfigSettingsWriter());
 		this.server.start();
 	}
 

src/main/java/core/packetproxy/gui/SwingConfigHttpUiActions.java

@@ -0,0 +1,46 @@
+/*
+ * Copyright 2026 DeNA Co., Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package packetproxy.gui;
+
+import javax.swing.JOptionPane;
+import packetproxy.common.ConfigHttpUiActions;
+import packetproxy.common.I18nString;
+
+public class SwingConfigHttpUiActions implements ConfigHttpUiActions {
+
+	@Override
+	public boolean confirmOverwriteConfig() {
+		try {
+			return confirmOverwriteConfigInternal();
+		} catch (Exception e) {
+			throw new IllegalStateException(e);
+		}
+	}
+
+	private boolean confirmOverwriteConfigInternal() throws Exception {
+		var main = GUIMain.getInstance();
+		main.setAlwaysOnTop(true);
+		try {
+			main.setVisible(true);
+			main.getTabbedPane().setSelectedIndex(GUIMain.Panes.OPTIONS.ordinal());
+			int option = JOptionPane.showConfirmDialog(main, I18nString.get("Do you want to overwrite config?"),
+					I18nString.get("Loading config"), JOptionPane.YES_NO_OPTION, JOptionPane.WARNING_MESSAGE);
+			return option == JOptionPane.YES_OPTION;
+		} finally {
+			main.setAlwaysOnTop(false);
+		}
+	}
+}

src/test/java/packetproxy/common/ConfigHttpServerTest.java

@@ -0,0 +1,123 @@
+/*
+ * Copyright 2026 DeNA Co., Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package packetproxy.common;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.mockito.ArgumentMatchers.any;
+import static org.mockito.ArgumentMatchers.anyString;
+import static org.mockito.Mockito.doAnswer;
+import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.never;
+import static org.mockito.Mockito.verify;
+import static org.mockito.Mockito.when;
+
+import fi.iki.elonen.NanoHTTPD.IHTTPSession;
+import fi.iki.elonen.NanoHTTPD.Method;
+import fi.iki.elonen.NanoHTTPD.Response;
+import java.io.InputStream;
+import java.nio.charset.StandardCharsets;
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.Map;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.NullAndEmptySource;
+import org.junit.jupiter.params.provider.ValueSource;
+
+public class ConfigHttpServerTest {
+
+	private static final String TOKEN = "secret-token";
+
+	private ConfigHttpUiActions uiActions;
+	private ConfigSettingsWriter settingsWriter;
+	private ConfigHttpServer server;
+
+	@BeforeEach
+	public void setUp() {
+		uiActions = mock(ConfigHttpUiActions.class);
+		settingsWriter = mock(ConfigSettingsWriter.class);
+		server = new ConfigHttpServer("127.0.0.1", 0, TOKEN, uiActions, settingsWriter);
+	}
+
+	@ParameterizedTest
+	@NullAndEmptySource
+	@ValueSource(strings = {"wrong-token"})
+	public void serve_rejectsUnauthorizedToken(String authorization) throws Exception {
+		var session = mockSession(Method.POST, "/config", authorization, null);
+
+		var response = server.serve(session);
+
+		assertEquals(Response.Status.UNAUTHORIZED, response.getStatus());
+		verify(uiActions, never()).confirmOverwriteConfig();
+		verify(settingsWriter, never()).applyFromJson(anyString());
+	}
+
+	@Test
+	public void serve_postConfig_rejectsWhenConfirmDenied() throws Exception {
+		when(uiActions.confirmOverwriteConfig()).thenReturn(false);
+		var session = mockSession(Method.POST, "/config", TOKEN, "{\"servers\":[]}");
+
+		var response = server.serve(session);
+
+		assertEquals(Response.Status.UNAUTHORIZED, response.getStatus());
+		verify(uiActions).confirmOverwriteConfig();
+		verify(settingsWriter, never()).applyFromJson(anyString());
+	}
+
+	@Test
+	public void serve_postConfig_appliesJsonWhenConfirmAccepted() throws Exception {
+		when(uiActions.confirmOverwriteConfig()).thenReturn(true);
+		var postData = "{\"servers\":[]}";
+		var session = mockSession(Method.POST, "/config", TOKEN, postData);
+
+		var response = server.serve(session);
+
+		assertEquals(Response.Status.OK, response.getStatus());
+		assertEquals("application/json", response.getMimeType());
+		assertEquals("{\"status\": \"ok\"}", readBody(response));
+		verify(uiActions).confirmOverwriteConfig();
+		verify(settingsWriter).applyFromJson(postData);
+	}
+
+	private static IHTTPSession mockSession(Method method, String uri, String authorization, String postData)
+			throws Exception {
+		var session = mock(IHTTPSession.class);
+		when(session.getMethod()).thenReturn(method);
+		when(session.getUri()).thenReturn(uri);
+		Map<String, String> headers = new HashMap<>();
+		if (authorization != null) {
+			headers.put("authorization", authorization);
+		}
+		when(session.getHeaders()).thenReturn(Collections.unmodifiableMap(headers));
+		if (postData != null) {
+			doAnswer(invocation -> {
+				Map<String, String> map = invocation.getArgument(0);
+				map.put("postData", postData);
+				return null;
+			}).when(session).parseBody(any());
+		}
+		return session;
+	}
+
+	private static String readBody(Response response) throws Exception {
+		InputStream data = response.getData();
+		if (data == null) {
+			return null;
+		}
+		return new String(data.readAllBytes(), StandardCharsets.UTF_8);
+	}
+}