fix: resolve SYSTEM theme to concrete DARK/LIGHT before crossing process boundary

Instead of passing the raw ThemeType name ("SYSTEM") to the :napplet process,
resolve it to the actual dark/light value in the main process by reading
context.resources.configuration.uiMode before the launch. The napplet process
now always receives "DARK" or "LIGHT" and sets UiModeManager.nightMode
unconditionally, making prefers-color-scheme reliable on all ThemeType choices.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_0198rKcuv32DEoUPpLqsBYbx

amethyst/src/main/java/com/vitorpamplona/amethyst/favorites/FavoriteAppLauncher.kt

@@ -22,6 +22,7 @@ package com.vitorpamplona.amethyst.favorites
 
 import android.app.Activity
 import android.content.Context
+import android.content.res.Configuration
 import android.os.Bundle
 import android.util.Log
 import android.widget.Toast
@@ -29,6 +30,7 @@ import com.vitorpamplona.amethyst.Amethyst
 import com.vitorpamplona.amethyst.R
 import com.vitorpamplona.amethyst.commons.favorites.FavoriteApp
 import com.vitorpamplona.amethyst.model.LocalCache
+import com.vitorpamplona.amethyst.model.ThemeType
 import com.vitorpamplona.amethyst.napplet.NappletLauncher
 import com.vitorpamplona.amethyst.napplet.WebUrlNetworkRegistry
 import com.vitorpamplona.amethyst.napplethost.NappletBrowserActivity
@@ -77,7 +79,16 @@ object FavoriteAppLauncher {
     ) {
         val proxyPort = Amethyst.instance.torManager.activePortOrNull.value ?: -1
         val useTor = proxyPort > 0 && (preferTor || WebUrlNetworkRegistry.useTor(url))
-        val theme = Amethyst.instance.uiPrefs.value.theme.value.name
+        val themeType = Amethyst.instance.uiPrefs.value.theme.value
+        val theme =
+            when (themeType) {
+                ThemeType.DARK -> "DARK"
+                ThemeType.LIGHT -> "LIGHT"
+                ThemeType.SYSTEM -> {
+                    val nightMask = context.resources.configuration.uiMode and Configuration.UI_MODE_NIGHT_MASK
+                    if (nightMask == Configuration.UI_MODE_NIGHT_YES) "DARK" else "LIGHT"
+                }
+            }
         val intent =
             NappletBrowserActivity.intent(context, url, proxyPort, useTor, theme = theme).apply {
                 if (context !is Activity) addFlags(android.content.Intent.FLAG_ACTIVITY_NEW_TASK)

amethyst/src/main/java/com/vitorpamplona/amethyst/napplet/NappletLauncher.kt

@@ -22,12 +22,14 @@ package com.vitorpamplona.amethyst.napplet
 
 import android.content.Context
 import android.content.Intent
+import android.content.res.Configuration
 import android.os.Bundle
 import com.vitorpamplona.amethyst.Amethyst
 import com.vitorpamplona.amethyst.commons.napplet.NappletCapability
 import com.vitorpamplona.amethyst.commons.napplet.NappletIdentity
 import com.vitorpamplona.amethyst.commons.napplet.resolveRequiredCapabilities
 import com.vitorpamplona.amethyst.model.LocalCache
+import com.vitorpamplona.amethyst.model.ThemeType
 import com.vitorpamplona.amethyst.napplethost.NappletHostActivity
 import com.vitorpamplona.amethyst.napplethost.NappletHostContract
 import com.vitorpamplona.quartz.nip01Core.core.HexKey
@@ -134,7 +136,16 @@ object NappletLauncher {
         // Resolve capability labels here (the app has the resources) so the sandbox module needs none.
         val capLabels = declared.map { context.getString(it.labelRes()) }
 
-        val theme = Amethyst.instance.uiPrefs.value.theme.value.name
+        val themeType = Amethyst.instance.uiPrefs.value.theme.value
+        val theme =
+            when (themeType) {
+                ThemeType.DARK -> "DARK"
+                ThemeType.LIGHT -> "LIGHT"
+                ThemeType.SYSTEM -> {
+                    val nightMask = context.resources.configuration.uiMode and Configuration.UI_MODE_NIGHT_MASK
+                    if (nightMask == Configuration.UI_MODE_NIGHT_YES) "DARK" else "LIGHT"
+                }
+            }
 
         return Bundle().apply {
             putStringArrayList(NappletHostContract.EXTRA_PATHS, ArrayList(paths.map { it.path }))

amethyst/src/main/java/com/vitorpamplona/amethyst/ui/screen/loggedIn/embed/EmbeddedTabFactory.kt

@@ -21,6 +21,7 @@
 package com.vitorpamplona.amethyst.ui.screen.loggedIn.embed
 
 import android.content.Context
+import android.content.res.Configuration
 import android.os.Build
 import android.os.Bundle
 import androidx.annotation.RequiresApi
@@ -28,6 +29,7 @@ import com.vitorpamplona.amethyst.Amethyst
 import com.vitorpamplona.amethyst.commons.favorites.FavoriteApp
 import com.vitorpamplona.amethyst.commons.tor.TorType
 import com.vitorpamplona.amethyst.favorites.FavoriteAppLauncher
+import com.vitorpamplona.amethyst.model.ThemeType
 import com.vitorpamplona.amethyst.napplet.WebUrlNetworkRegistry
 import com.vitorpamplona.amethyst.napplethost.NappletHostContract
 import com.vitorpamplona.amethyst.ui.screen.loggedIn.browser.EmbeddedBrowserController
@@ -57,7 +59,16 @@ object EmbeddedTabFactory {
         EmbeddedTabHost.acquire(browserId(url)) {
             val proxyPort = Amethyst.instance.torManager.activePortOrNull.value ?: -1
             val initialUseTor = proxyPort > 0 && WebUrlNetworkRegistry.useTor(url)
-            val theme = Amethyst.instance.uiPrefs.value.theme.value.name
+            val themeType = Amethyst.instance.uiPrefs.value.theme.value
+            val theme =
+                when (themeType) {
+                    ThemeType.DARK -> "DARK"
+                    ThemeType.LIGHT -> "LIGHT"
+                    ThemeType.SYSTEM -> {
+                        val nightMask = context.resources.configuration.uiMode and Configuration.UI_MODE_NIGHT_MASK
+                        if (nightMask == Configuration.UI_MODE_NIGHT_YES) "DARK" else "LIGHT"
+                    }
+                }
             EmbeddedBrowserController(context.applicationContext, proxyPort, initialUseTor, backgroundColor, theme).also { it.bind(url) }
         } as EmbeddedBrowserController
 

nappletHost/src/main/kotlin/com/vitorpamplona/amethyst/napplethost/NappletBrowserActivity.kt

@@ -624,7 +624,6 @@ class NappletBrowserActivity : ComponentActivity() {
         when (themeType) {
             "DARK" -> uiManager.nightMode = android.app.UiModeManager.MODE_NIGHT_YES
             "LIGHT" -> uiManager.nightMode = android.app.UiModeManager.MODE_NIGHT_NO
-            else -> {} // SYSTEM: follow the device setting (process default)
         }
     }
 

nappletHost/src/main/kotlin/com/vitorpamplona/amethyst/napplethost/NappletBrowserService.kt

@@ -143,7 +143,6 @@ class NappletBrowserService : Service() {
         when (themeType) {
             "DARK" -> uiManager.nightMode = android.app.UiModeManager.MODE_NIGHT_YES
             "LIGHT" -> uiManager.nightMode = android.app.UiModeManager.MODE_NIGHT_NO
-            else -> {} // SYSTEM: follow the device setting (process default)
         }
     }
 

nappletHost/src/main/kotlin/com/vitorpamplona/amethyst/napplethost/NappletHostActivity.kt

@@ -803,7 +803,6 @@ class NappletHostActivity : ComponentActivity() {
         when (themeType) {
             "DARK" -> uiManager.nightMode = android.app.UiModeManager.MODE_NIGHT_YES
             "LIGHT" -> uiManager.nightMode = android.app.UiModeManager.MODE_NIGHT_NO
-            else -> {} // SYSTEM: follow the device setting (process default)
         }
     }
 

nappletHost/src/main/kotlin/com/vitorpamplona/amethyst/napplethost/NappletHostService.kt

@@ -192,7 +192,6 @@ class NappletHostService : Service() {
         when (themeType) {
             "DARK" -> uiManager.nightMode = android.app.UiModeManager.MODE_NIGHT_YES
             "LIGHT" -> uiManager.nightMode = android.app.UiModeManager.MODE_NIGHT_NO
-            else -> {} // SYSTEM: follow the device setting (process default)
         }
     }