Refactor VPN mode checks and TUN config logic

Centralizes VPN mode detection in SettingsManager with a new isVpnMode() method and updates all usages to reference it. Refactors TUN configuration logic in V2rayConfigManager for clarity and correctness, ensuring proper config and routing rules are applied based on VPN and HEV TUN settings.

V2rayNG/app/src/main/java/com/v2ray/ang/handler/SettingsManager.kt

@@ -10,6 +10,7 @@ import com.v2ray.ang.AppConfig.ANG_PACKAGE
 import com.v2ray.ang.AppConfig.GEOIP_PRIVATE
 import com.v2ray.ang.AppConfig.GEOSITE_PRIVATE
 import com.v2ray.ang.AppConfig.TAG_DIRECT
+import com.v2ray.ang.AppConfig.VPN
 import com.v2ray.ang.dto.EConfigType
 import com.v2ray.ang.dto.Language
 import com.v2ray.ang.dto.ProfileItem
@@ -386,6 +387,15 @@ object SettingsManager {
         return MmkvManager.decodeSettingsBool(AppConfig.PREF_USE_HEV_TUNNEL, true)
     }
 
+    /**
+     * Check if VPN mode is enabled.
+     * @return True if VPN mode is enabled, false otherwise.
+     */
+    fun isVpnMode(): Boolean {
+        val mode = MmkvManager.decodeSettingsString(AppConfig.PREF_MODE)
+        return mode == null || mode == VPN
+    }
+
     /**
      * Ensure default settings are present in MMKV.
      */

V2rayNG/app/src/main/java/com/v2ray/ang/handler/V2RayServiceManager.kt

@@ -108,7 +108,7 @@ object V2RayServiceManager {
         } else {
             context.toast(R.string.toast_services_start)
         }
-        val intent = if ((MmkvManager.decodeSettingsString(AppConfig.PREF_MODE) ?: AppConfig.VPN) == AppConfig.VPN) {
+        val intent = if (SettingsManager.isVpnMode()) {
             Intent(context.applicationContext, V2RayVpnService::class.java)
         } else {
             Intent(context.applicationContext, V2RayProxyOnlyService::class.java)

V2rayNG/app/src/main/java/com/v2ray/ang/handler/V2rayConfigManager.kt

@@ -91,7 +91,7 @@ object V2rayConfigManager {
     private fun getV2rayCustomConfig(context: Context, guid: String, config: ProfileItem): ConfigResult {
         val raw = MmkvManager.decodeServerRaw(guid) ?: return ConfigResult(false)
         val result = ConfigResult(true, guid, raw)
-        if (SettingsManager.isUsingHevTun()) {
+        if (!needTun()) {
             return result
         }
 
@@ -334,18 +334,18 @@ object V2rayConfigManager {
      */
     private fun initV2rayConfig(context: Context): V2rayConfig? {
         var assets = ""
-        if (SettingsManager.isUsingHevTun()) {
-            assets = initConfigCache ?: Utils.readTextFromAssets(context, "v2ray_config.json")
-            if (TextUtils.isEmpty(assets)) {
-                return null
-            }
-            initConfigCache = assets
-        } else {
+        if (needTun()) {
             assets = initConfigCacheWithTun ?: Utils.readTextFromAssets(context, "v2ray_config_with_tun.json")
             if (TextUtils.isEmpty(assets)) {
                 return null
             }
             initConfigCacheWithTun = assets
+        } else {
+            assets = initConfigCache ?: Utils.readTextFromAssets(context, "v2ray_config.json")
+            if (TextUtils.isEmpty(assets)) {
+                return null
+            }
+            initConfigCache = assets
         }
         val config = JsonUtil.fromJson(assets, V2rayConfig::class.java)
         return config
@@ -357,6 +357,10 @@ object V2rayConfigManager {
 
     //region some sub function
 
+    private fun needTun(): Boolean {
+        return SettingsManager.isVpnMode() && !SettingsManager.isUsingHevTun()
+    }
+
     /**
      * Configures the inbound settings for V2ray.
      *
@@ -395,7 +399,7 @@ object V2rayConfigManager {
                 v2rayConfig.inbounds.add(inbound2)
             }
 
-            if (!SettingsManager.isUsingHevTun()) {
+            if (needTun()) {
                 val inboundTun = v2rayConfig.inbounds.firstOrNull { e -> e.tag == "tun" }
                 inboundTun?.settings?.mtu = SettingsManager.getVpnMtu()
                 inboundTun?.sniffing = inbound1.sniffing
@@ -520,6 +524,7 @@ object V2rayConfigManager {
                 )
             }
 
+            if(SettingsManager.isVpnMode()) {
                 if (SettingsManager.isUsingHevTun()) {
                     //hev-socks5-tunnel dns routing
                     v2rayConfig.routing.rules.add(
@@ -538,6 +543,7 @@ object V2rayConfigManager {
                         )
                     )
                 }
+            }
 
             // DNS outbound
             if (v2rayConfig.outbounds.none { e -> e.protocol == "dns" && e.tag == "dns-out" }) {

V2rayNG/app/src/main/java/com/v2ray/ang/ui/MainActivity.kt

@@ -34,6 +34,7 @@ import com.v2ray.ang.extension.toastError
 import com.v2ray.ang.handler.AngConfigManager
 import com.v2ray.ang.handler.MmkvManager
 import com.v2ray.ang.handler.SettingsChangeManager
+import com.v2ray.ang.handler.SettingsManager
 import com.v2ray.ang.handler.V2RayServiceManager
 import com.v2ray.ang.util.Utils
 import com.v2ray.ang.viewmodel.MainViewModel
@@ -188,7 +189,7 @@ class MainActivity : BaseActivity(), NavigationView.OnNavigationItemSelectedList
 
         if (mainViewModel.isRunning.value == true) {
             V2RayServiceManager.stopVService(this)
-        } else if ((MmkvManager.decodeSettingsString(AppConfig.PREF_MODE) ?: VPN) == VPN) {
+        } else if (SettingsManager.isVpnMode()) {
             val intent = VpnService.prepare(this)
             if (intent == null) {
                 startV2Ray()