Add an option to copy global settings to per-game ones

app/src/main/java/emu/skyline/preference/CopyGlobalSettingsPreference.kt

@@ -0,0 +1,40 @@
+/*
+ * SPDX-License-Identifier: MPL-2.0
+ * Copyright © 2023 Skyline Team and Contributors (https://github.com/skyline-emu/)
+ */
+
+package emu.skyline.preference
+
+import android.app.Activity
+import android.content.Context
+import android.util.AttributeSet
+import androidx.preference.Preference
+import com.google.android.material.dialog.MaterialAlertDialogBuilder
+import emu.skyline.R
+import emu.skyline.settings.EmulationSettings
+
+/**
+ * Copies global emulation settings into the current shared preferences, showing a dialog to confirm the action
+ * This preference recreates the activity to update the UI after modifying shared preferences
+ */
+class CopyGlobalSettingsPreference @JvmOverloads constructor(context : Context, attrs : AttributeSet? = null, defStyleAttr : Int = androidx.preference.R.attr.preferenceStyle) : Preference(context, attrs, defStyleAttr) {
+    init {
+        setOnPreferenceClickListener {
+            MaterialAlertDialogBuilder(context)
+                .setTitle(title)
+                .setMessage(R.string.copy_global_settings_warning)
+                .setPositiveButton(android.R.string.ok) { _, _ ->
+                    // Copy global settings to the current ones
+                    val emulationSettings = EmulationSettings.forPrefName(preferenceManager.sharedPreferencesName)
+                    emulationSettings.copyFromGlobal()
+
+                    // Recreate the activity to update the UI after modifying shared preferences
+                    (context as? Activity)?.recreate()
+                }
+                .setNegativeButton(android.R.string.cancel, null)
+                .show()
+
+            true
+        }
+    }
+}

app/src/main/java/emu/skyline/settings/EmulationSettings.kt

@@ -10,6 +10,8 @@ import android.content.pm.ActivityInfo
 import emu.skyline.R
 import emu.skyline.SkylineApplication
 import emu.skyline.utils.sharedPreferences
+import kotlin.reflect.KMutableProperty
+import kotlin.reflect.full.memberProperties
 
 /**
  * Settings used during emulation. Use [forTitleId] to retrieve settings for a given `titleId`.
@@ -56,6 +58,23 @@ class EmulationSettings private constructor(context : Context, prefName : String
     // Debug
     var validationLayer by sharedPreferences(context, false, prefName = prefName)
 
+    /**
+     * Copies all settings from the global settings to this instance.
+     * This is a no-op if the instance this is called on is the global one
+     */
+    fun copyFromGlobal() {
+        if (isGlobal)
+            return
+
+        for (prop in EmulationSettings::class.memberProperties) {
+            if (prop.name == "useCustomSettings")
+                continue
+
+            if (prop is KMutableProperty<*>)
+                prop.setter.call(this, prop.get(global))
+        }
+    }
+
     companion object {
         const val SYSTEM_GPU_DRIVER = "system"
 
@@ -71,6 +90,11 @@ class EmulationSettings private constructor(context : Context, prefName : String
          */
         fun forTitleId(titleId : String) = EmulationSettings(SkylineApplication.context, prefNameForTitle(titleId))
 
+        /**
+         * Returns emulation settings for the given preferences name
+         */
+        fun forPrefName(prefName : String) = EmulationSettings(SkylineApplication.context, prefName)
+
         /**
          * Returns emulation settings to be used during emulation of the given `titleId`.
          * Global settings are returned if custom settings are disabled for this title

app/src/main/res/values/strings.xml

@@ -57,6 +57,9 @@
     <string name="reset_custom_settings">Reset Custom Settings</string>
     <string name="reset_custom_settings_desc">Reset custom settings to the default values</string>
     <string name="reset_settings_warning">Are you sure you want to reset all settings to the default values? <b>Current settings will be lost</b></string>
+    <string name="copy_global_settings">Copy Global Settings</string>
+    <string name="copy_global_settings_desc">Copy global settings to this game</string>
+    <string name="copy_global_settings_warning">Are you sure you want to copy global settings to this game? <b>Current settings will be lost</b></string>
     <!-- Settings - System -->
     <string name="system">System</string>
     <string name="use_docked">Use Docked Mode</string>

app/src/main/res/xml/custom_game_preferences.xml

@@ -13,5 +13,9 @@
             android:summary="@string/reset_custom_settings_desc"
             app:key="reset_custom_settings"
             app:title="@string/reset_custom_settings" />
+        <emu.skyline.preference.CopyGlobalSettingsPreference
+            android:summary="@string/copy_global_settings_desc"
+            app:key="copy_global_settings"
+            app:title="@string/copy_global_settings" />
     </PreferenceCategory>
 </androidx.preference.PreferenceScreen>