Add app.isNatEnabled for performance and readability

Warning: This is a boring commit.

src/main/scala/com/github/shadowsocks/ServiceBoundContext.scala

@@ -55,8 +55,7 @@ trait ServiceBoundContext extends Context with IBinder.DeathRecipient {
   def attachService(callback: IShadowsocksServiceCallback.Stub = null) {
     this.callback = callback
     if (bgService == null) {
-      val s =
-        if (app.isVpnEnabled) classOf[ShadowsocksVpnService] else classOf[ShadowsocksNatService]
+      val s = if (app.isNatEnabled) classOf[ShadowsocksNatService] else classOf[ShadowsocksVpnService]
 
       val intent = new Intent(this, s)
       intent.setAction(Action.SERVICE)

src/main/scala/com/github/shadowsocks/Shadowsocks.scala

@@ -130,10 +130,10 @@ class Shadowsocks extends AppCompatActivity with ServiceBoundContext {
             changeSwitch(checked = true)
             preferences.setEnabled(false)
             stat.setVisibility(View.VISIBLE)
-            if (app.isVpnEnabled) {
+            if (app.isNatEnabled) connectionTestText.setVisibility(View.GONE) else {
               connectionTestText.setVisibility(View.VISIBLE)
               connectionTestText.setText(getString(R.string.connection_test_pending))
-            } else connectionTestText.setVisibility(View.GONE)
+            }
           case State.STOPPED =>
             fab.setBackgroundTintList(greyTint)
             fabProgressCircle.postDelayed(hideCircle, 1000)
@@ -178,7 +178,7 @@ class Shadowsocks extends AppCompatActivity with ServiceBoundContext {
     // Update the UI
     if (fab != null) fab.setEnabled(true)
     updateState()
-    if (Build.VERSION.SDK_INT >= 21 && !app.isVpnEnabled) {
+    if (Build.VERSION.SDK_INT >= 21 && app.isNatEnabled) {
       val snackbar = Snackbar.make(findViewById(android.R.id.content), R.string.nat_deprecated, Snackbar.LENGTH_LONG)
       snackbar.setAction(R.string.switch_to_vpn, (_ => preferences.natSwitch.setChecked(false)): View.OnClickListener)
       snackbar.show
@@ -307,11 +307,7 @@ class Shadowsocks extends AppCompatActivity with ServiceBoundContext {
       cmd.append("chmod 666 %s/%s-vpn.pid".formatLocal(Locale.ENGLISH, getApplicationInfo.dataDir, task))
     }
 
-    if (app.isVpnEnabled) {
-      Console.runCommand(cmd.toArray)
-    } else {
-      Console.runRootCommand(cmd.toArray)
-    }
+    if (app.isNatEnabled) Console.runRootCommand(cmd.toArray) else Console.runCommand(cmd.toArray)
 
     cmd.clear()
 
@@ -331,10 +327,10 @@ class Shadowsocks extends AppCompatActivity with ServiceBoundContext {
       cmd.append("rm -f %s/%s-vpn.pid".formatLocal(Locale.ENGLISH, getApplicationInfo.dataDir, task))
       cmd.append("rm -f %s/%s-vpn.conf".formatLocal(Locale.ENGLISH, getApplicationInfo.dataDir, task))
     }
-    if (app.isVpnEnabled) Console.runCommand(cmd.toArray) else {
+    if (app.isNatEnabled) {
       Console.runRootCommand(cmd.toArray)
       Console.runRootCommand(Utils.iptables + " -t nat -F OUTPUT")
-    }
+    } else Console.runCommand(cmd.toArray)
   }
 
   def cancelStart() {
@@ -344,15 +340,13 @@ class Shadowsocks extends AppCompatActivity with ServiceBoundContext {
 
   def prepareStartService() {
     Utils.ThrowableFuture {
-      if (app.isVpnEnabled) {
+      if (app.isNatEnabled) serviceLoad() else {
         val intent = VpnService.prepare(this)
         if (intent != null) {
           startActivityForResult(intent, REQUEST_CONNECT)
         } else {
           handler.post(() => onActivityResult(REQUEST_CONNECT, Activity.RESULT_OK, null))
         }
-      } else {
-        serviceLoad()
       }
     }
   }
@@ -412,14 +406,11 @@ class Shadowsocks extends AppCompatActivity with ServiceBoundContext {
                 success = false
                 result = getString(R.string.connection_test_error, e.getMessage)
             }
-            synchronized(if (testCount == id) {
-              if (app.isVpnEnabled) handler.post(() => {
-                if (success) connectionTestText.setText(result) else {
-                  connectionTestText.setText(R.string.connection_test_fail)
-                  Snackbar.make(findViewById(android.R.id.content), result, Snackbar.LENGTH_LONG).show
-                }
-              })
-            })
+            synchronized(if (testCount == id && app.isVpnEnabled) handler.post(() =>
+              if (success) connectionTestText.setText(result) else {
+                connectionTestText.setText(R.string.connection_test_fail)
+                Snackbar.make(findViewById(android.R.id.content), result, Snackbar.LENGTH_LONG).show
+              }))
           }
         }
       }
@@ -470,10 +461,10 @@ class Shadowsocks extends AppCompatActivity with ServiceBoundContext {
           preferences.setEnabled(false)
           fabProgressCircle.postDelayed(hideCircle, 100)
           stat.setVisibility(View.VISIBLE)
-          if (app.isVpnEnabled) {
+          if (app.isNatEnabled) connectionTestText.setVisibility(View.GONE) else {
             connectionTestText.setVisibility(View.VISIBLE)
             connectionTestText.setText(getString(R.string.connection_test_pending))
-          } else connectionTestText.setVisibility(View.GONE)
+          }
         case State.STOPPING =>
           fab.setBackgroundTintList(greyTint)
           serviceStarted = false

src/main/scala/com/github/shadowsocks/ShadowsocksApplication.scala

@@ -67,7 +67,8 @@ class ShadowsocksApplication extends Application {
   lazy val editor = settings.edit
   lazy val profileManager = new ProfileManager(settings, dbHelper)
 
-  def isVpnEnabled = !settings.getBoolean(Key.isNAT, false)
+  def isNatEnabled = settings.getBoolean(Key.isNAT, false)
+  def isVpnEnabled = !isNatEnabled
 
   def getVersionName = try {
     getPackageManager.getPackageInfo(getPackageName, 0).versionName

src/main/scala/com/github/shadowsocks/ShadowsocksRunnerActivity.scala

@@ -65,16 +65,16 @@ class ShadowsocksRunnerActivity extends Activity with ServiceBoundContext {
   }
 
   def startBackgroundService() {
-    if (app.isVpnEnabled) {
+    if (app.isNatEnabled) {
+      bgService.use(ConfigUtils.loadFromSharedPreferences)
+      finish()
+    } else {
       val intent = VpnService.prepare(ShadowsocksRunnerActivity.this)
       if (intent != null) {
         startActivityForResult(intent, REQUEST_CONNECT)
       } else {
         onActivityResult(REQUEST_CONNECT, Activity.RESULT_OK, null)
       }
-    } else {
-      bgService.use(ConfigUtils.loadFromSharedPreferences)
-      finish()
     }
   }
 

src/main/scala/com/github/shadowsocks/ShadowsocksRunnerService.scala

@@ -58,15 +58,13 @@ class ShadowsocksRunnerService extends Service with ServiceBoundContext {
   }
 
   def startBackgroundService() {
-    if (app.isVpnEnabled) {
+    if (app.isNatEnabled) bgService.use(ConfigUtils.loadFromSharedPreferences) else {
       val intent = VpnService.prepare(ShadowsocksRunnerService.this)
       if (intent == null) {
         if (bgService != null) {
           bgService.use(ConfigUtils.loadFromSharedPreferences)
         }
       }
-    } else {
-      bgService.use(ConfigUtils.loadFromSharedPreferences)
     }
     stopSelf()
   }

src/main/scala/com/github/shadowsocks/ShadowsocksSettings.scala

@@ -156,7 +156,7 @@ class ShadowsocksSettings extends PreferenceFragment with OnSharedPreferenceChan
     for (name <- Key.isNAT #:: PROXY_PREFS.toStream #::: FEATURE_PREFS.toStream) {
       val pref = findPreference(name)
       if (pref != null) pref.setEnabled(enabled &&
-        (name != Key.isProxyApps || Utils.isLollipopOrAbove || !app.isVpnEnabled))
+        (name != Key.isProxyApps || Utils.isLollipopOrAbove || app.isNatEnabled))
     }
   }