feat(youtube): add language-switch patch

src/main/kotlin/app/revanced/patches/youtube/misc/language/fingerprints/GeneralPrefsFingerprint.kt

@@ -0,0 +1,18 @@
+package app.revanced.patches.youtube.misc.language.fingerprints
+
+import app.revanced.patcher.fingerprint.method.impl.MethodFingerprint
+import org.jf.dexlib2.Opcode
+
+object GeneralPrefsFingerprint : MethodFingerprint(
+    returnType = "V",
+    parameters = listOf(),
+    opcodes = listOf(
+        Opcode.INVOKE_VIRTUAL,
+        Opcode.MOVE_RESULT,
+        Opcode.IF_NEZ,
+        Opcode.INVOKE_VIRTUAL,
+        Opcode.MOVE_RESULT_OBJECT
+    ),
+    strings = listOf("bedtime_reminder_toggle"),
+    customFingerprint = { it, _ -> it.definingClass.endsWith("GeneralPrefsFragment;") }
+)

src/main/kotlin/app/revanced/patches/youtube/misc/language/patch/LanguageSelectorPatch.kt

@@ -0,0 +1,47 @@
+package app.revanced.patches.youtube.misc.language.patch
+
+import app.revanced.extensions.toErrorResult
+import app.revanced.patcher.annotation.Description
+import app.revanced.patcher.annotation.Name
+import app.revanced.patcher.annotation.Version
+import app.revanced.patcher.data.BytecodeContext
+import app.revanced.patcher.extensions.InstructionExtensions.addInstruction
+import app.revanced.patcher.extensions.InstructionExtensions.getInstruction
+import app.revanced.patcher.patch.BytecodePatch
+import app.revanced.patcher.patch.PatchResult
+import app.revanced.patcher.patch.PatchResultSuccess
+import app.revanced.patcher.patch.annotations.DependsOn
+import app.revanced.patcher.patch.annotations.Patch
+import app.revanced.patches.shared.annotation.YouTubeCompatibility
+import app.revanced.patches.youtube.misc.language.fingerprints.GeneralPrefsFingerprint
+import app.revanced.patches.youtube.utils.settings.resource.patch.SettingsPatch
+import org.jf.dexlib2.iface.instruction.OneRegisterInstruction
+
+@Patch
+@Name("language-switch")
+@Description("Add language switch toggle.")
+@DependsOn([SettingsPatch::class])
+@YouTubeCompatibility
+@Version("0.0.1")
+class LanguageSelectorPatch : BytecodePatch(
+    listOf(GeneralPrefsFingerprint)
+) {
+    override fun execute(context: BytecodeContext): PatchResult {
+
+        GeneralPrefsFingerprint.result?.let {
+            it.mutableMethod.apply {
+                val targetIndex = it.scanResult.patternScanResult!!.startIndex + 2
+                val targetRegister = getInstruction<OneRegisterInstruction>(targetIndex).registerA
+
+                addInstruction(
+                    targetIndex,
+                    "const/4 v$targetRegister, 0x1"
+                )
+            }
+        } ?: return GeneralPrefsFingerprint.toErrorResult()
+
+        SettingsPatch.updatePatchStatus("language-switch")
+
+        return PatchResultSuccess()
+    }
+}