feat(proxy): add single node delay testing with UI integration

ref: MetaCubeX/ClashMetaForAndroid#683
MetaCubeX/ClashMetaForAndroid#683

Author: YumeYuka

app/src/main/kotlin/com/github/yumelira/yumebox/screen/settings/AppSettingsScreen.kt

@@ -251,6 +251,12 @@ fun AppSettingsScreen(
                         checked = showTrafficNotification,
                         onCheckedChange = { viewModel.onShowTrafficNotificationChange(it) },
                     )
+                    SuperSwitch(
+                        title = MLang.AppSettings.ServiceSection.SingleNodeTestTitle,
+                        summary = MLang.AppSettings.ServiceSection.SingleNodeTestSummary,
+                        checked = viewModel.singleNodeTest.state.collectAsState().value,
+                        onCheckedChange = { viewModel.onSingleNodeTestChange(it) },
+                    )
                 }
                 SmallTitle(MLang.AppSettings.Section.Network)
                 Card {

app/src/main/kotlin/com/github/yumelira/yumebox/screen/settings/AppSettingsViewModel.kt

@@ -45,6 +45,7 @@ class AppSettingsViewModel(
     val bottomBarAutoHide: Preference<Boolean> = repository.bottomBarAutoHide
     val topBarBlurEnabled: Preference<Boolean> = repository.topBarBlurEnabled
     val pageScale: Preference<Float> = repository.pageScale
+    val singleNodeTest: Preference<Boolean> = repository.singleNodeTest
 
     val customUserAgent: Preference<String> = repository.customUserAgent
 
@@ -61,6 +62,7 @@ class AppSettingsViewModel(
     fun onHideAppIconChange(hide: Boolean) = hideAppIcon.set(hide)
     fun onExcludeFromRecentsChange(exclude: Boolean) = excludeFromRecents.set(exclude)
     fun onShowTrafficNotificationChange(show: Boolean) = showTrafficNotification.set(show)
+    fun onSingleNodeTestChange(enabled: Boolean) = singleNodeTest.set(enabled)
 
     fun applyCustomUserAgent(userAgent: String) = repository.applyCustomUserAgent(userAgent)
 

core/src/cpp/main.c

@@ -233,6 +233,18 @@ Java_com_github_yumelira_yumebox_core_bridge_Bridge_nativeHealthCheckAll(JNIEnv
     healthCheckAll();
 }
 
+JNIEXPORT void JNICALL
+Java_com_github_yumelira_yumebox_core_bridge_Bridge_nativeHealthCheckProxy(JNIEnv *env, jobject thiz,
+jobject completable,
+jstring proxy_name) {
+TRACE_METHOD();
+
+jobject _completable = new_global(completable);
+scoped_string _proxy_name = get_string(proxy_name);
+
+healthCheckProxy(_completable, _proxy_name);
+}
+
 JNIEXPORT jboolean JNICALL
 Java_com_github_yumelira_yumebox_core_bridge_Bridge_nativePatchSelector(JNIEnv *env, jobject thiz,
                                                                    jstring selector, jstring name) {
@@ -345,6 +357,7 @@ static jmethodID m_tun_interface_mark_socket;
 static jmethodID m_tun_interface_query_socket_uid;
 static jmethodID m_completable_complete;
 static jmethodID m_completable_complete_exceptionally;
+    static jmethodID m_completable_complete_with_string;
 static jmethodID m_logcat_interface_received;
 static jmethodID m_clash_exception;
 static jmethodID m_fetch_callback_report;
@@ -403,6 +416,17 @@ static void call_completable_complete_impl(void *completable, const char *except
     }
 }
 
+    static void call_completable_complete_with_string_impl(void *completable, const char *result) {
+    TRACE_METHOD();
+
+    ATTACH_JNI();
+
+    (*env)->CallBooleanMethod(env,
+    (jobject) completable,
+    (jmethodID) m_completable_complete_with_string,
+    (jstring) new_string(result));
+    }
+
 static void call_fetch_callback_report_impl(void *fetch_callback, const char *status_json) {
     TRACE_METHOD();
 
@@ -521,6 +545,8 @@ JNI_OnLoad(JavaVM *vm, void *reserved) {
                                             "(Ljava/lang/String;)V");
     m_completable_complete_exceptionally = find_method(c_completable, "completeExceptionally",
                                                        "(Ljava/lang/Throwable;)Z");
+    // Reuse complete(Object) for complete_with_string - String is an Object
+    m_completable_complete_with_string = m_completable_complete;
     m_logcat_interface_received = find_method(c_logcat_interface, "received",
                                               "(Ljava/lang/String;)V");
     m_clash_exception = find_method(_c_clash_exception, "<init>",
@@ -541,6 +567,7 @@ JNI_OnLoad(JavaVM *vm, void *reserved) {
     mark_socket_func = &call_tun_interface_mark_socket_impl;
     query_socket_uid_func = &call_tun_interface_query_socket_uid_impl;
     complete_func = &call_completable_complete_impl;
+    complete_with_string_func = &call_completable_complete_with_string_impl;
     fetch_report_func = &call_fetch_callback_report_impl;
     fetch_complete_func = &call_fetch_callback_complete_impl;
     logcat_received_func = &call_logcat_interface_received_impl;

core/src/golang/native/bridge.c

@@ -13,6 +13,8 @@ int (*query_socket_uid_func)(void *tun_interface, int protocol, const char *sour
 
 void (*complete_func)(void *completable, const char *exception);
 
+void (*complete_with_string_func)(void *completable, const char *result);
+
 void (*fetch_report_func)(void *fetch_callback, const char *status_json);
 
 void (*fetch_complete_func)(void *fetch_callback, const char *error);
@@ -48,6 +50,14 @@ void complete(void *obj, char *error) {
     free(error);
 }
 
+void complete_with_string(void *obj, char *result) {
+TRACE_METHOD();
+
+complete_with_string_func(obj, result);
+
+free(result);
+}
+
 void fetch_complete(void *fetch_callback, char *exception) {
     TRACE_METHOD();
 

core/src/golang/native/bridge.h

@@ -21,6 +21,8 @@ extern int (*query_socket_uid_func)(void *tun_interface, int protocol, const cha
 
 extern void (*complete_func)(void *completable, const char *exception);
 
+extern void (*complete_with_string_func)(void *completable, const char *result);
+
 extern void (*fetch_report_func)(void *fetch_callback, const char *status_json);
 
 extern void (*fetch_complete_func)(void *fetch_callback, const char *error);
@@ -38,6 +40,8 @@ extern int query_socket_uid(void *interface, int protocol, char *source, char *t
 
 extern void complete(void *obj, char *error);
 
+extern void complete_with_string(void *obj, char *result);
+
 extern void fetch_complete(void *completable, char *exception);
 
 extern void fetch_report(void *fetch_callback, char *status_json);

core/src/golang/native/tunnel.go

@@ -79,6 +79,20 @@ func healthCheckAll() {
 	tunnel.HealthCheckAll()
 }
 
+//export healthCheckProxy
+func healthCheckProxy(completable unsafe.Pointer, proxyName C.c_string) {
+	go func(name string) {
+		delay := tunnel.HealthCheckProxy(name)
+
+		// Return delay as JSON response
+		response := &struct {
+			Delay int `json:"delay"`
+		}{delay}
+
+		C.complete_with_string(completable, marshalJson(response))
+	}(C.GoString(proxyName))
+}
+
 //export patchSelector
 func patchSelector(selector, name C.c_string) C.int {
 	s := C.GoString(selector)

core/src/golang/native/tunnel/connectivity.go

@@ -1,7 +1,9 @@
 package tunnel
 
 import (
+	"context"
 	"sync"
+	"time"
 
 	"github.com/metacubex/mihomo/adapter/outboundgroup"
 	"github.com/metacubex/mihomo/constant/provider"
@@ -47,3 +49,28 @@ func HealthCheckAll() {
 		}(g)
 	}
 }
+
+// HealthCheckProxy performs health check on a single proxy by name
+func HealthCheckProxy(proxyName string) int {
+	p := tunnel.Proxies()[proxyName]
+	if p == nil {
+		log.Warnln("HealthCheckProxy: proxy `%s` not found", proxyName)
+		return -1
+	}
+
+	ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
+	defer cancel()
+
+	testURL := "https://www.gstatic.com/generate_204"
+	_, _ = p.URLTest(ctx, testURL, nil)
+	delay := p.LastDelayForTestUrl(testURL)
+
+	// Convert 65535 (failure) to -1
+	if delay == 0xffff {
+		log.Debugln("HealthCheckProxy: proxy=%s, timeout/failed", proxyName)
+		return -1
+	}
+
+	log.Debugln("HealthCheckProxy: proxy=%s, delay=%dms", proxyName, delay)
+	return int(delay)
+}

core/src/kotlin/com/github/yumelira/yumebox/core/Clash.kt

@@ -174,6 +174,12 @@ object Clash {
         }
     }
 
+    fun healthCheckProxy(proxyName: String): CompletableDeferred<String> {
+        return CompletableDeferred<String>().apply {
+            Bridge.nativeHealthCheckProxy(this, proxyName)
+        }
+    }
+
     fun healthCheckAll() {
         Bridge.nativeHealthCheckAll()
     }

core/src/kotlin/com/github/yumelira/yumebox/core/bridge/Bridge.kt

@@ -47,6 +47,7 @@ object Bridge {
     external fun nativeQueryProfileGroups(path: String, excludeNotSelectable: Boolean): String?
     external fun nativeQueryGroup(name: String, sort: String): String?
     external fun nativeHealthCheck(completable: CompletableDeferred<Unit>, name: String)
+    external fun nativeHealthCheckProxy(completable: CompletableDeferred<String>, proxyName: String)
     external fun nativeHealthCheckAll()
     external fun nativePatchSelector(selector: String, name: String): Boolean
     external fun nativeFetchAndValid(

data/settings/src/main/kotlin/com/github/yumelira/yumebox/data/repository/AppSettingsRepository.kt

@@ -43,6 +43,7 @@ class AppSettingsRepository(
     val bottomBarAutoHide: Preference<Boolean> = storage.bottomBarAutoHide
     val topBarBlurEnabled: Preference<Boolean> = storage.topBarBlurEnabled
     val pageScale: Preference<Float> = storage.pageScale
+    val singleNodeTest: Preference<Boolean> = storage.singleNodeTest
 
     val customUserAgent: Preference<String> = storage.customUserAgent