feat(backdrops): pro-unlock patch (#1121)

src/main/kotlin/app/revanced/patches/backdrops/misc/pro/annotations/ProUnlockCompatibility.kt

@@ -0,0 +1,7 @@
+package app.revanced.patches.backdrops.misc.pro.annotations
+
+import app.revanced.patcher.annotation.Compatibility
+import app.revanced.patcher.annotation.Package
+
+@Compatibility([Package("com.backdrops.wallpapers")])
+internal annotation class ProUnlockCompatibility

src/main/kotlin/app/revanced/patches/backdrops/misc/pro/fingerprints/ProUnlockFingerprint.kt

@@ -0,0 +1,15 @@
+package app.revanced.patches.backdrops.misc.pro.fingerprints
+
+import app.revanced.patcher.fingerprint.method.impl.MethodFingerprint
+import org.jf.dexlib2.Opcode
+
+object ProUnlockFingerprint : MethodFingerprint(
+    opcodes = listOf(
+        Opcode.INVOKE_VIRTUAL,
+        Opcode.MOVE_RESULT_OBJECT,
+        Opcode.INVOKE_INTERFACE,
+        Opcode.MOVE_RESULT,
+        Opcode.IF_EQZ
+    ),
+    customFingerprint = { it.definingClass == "Lcom/backdrops/wallpapers/data/local/DatabaseHandlerIAB;" && it.name == "lambda\$existPurchase\$0" }
+)

src/main/kotlin/app/revanced/patches/backdrops/misc/pro/patch/ProUnlockPatch.kt

@@ -0,0 +1,42 @@
+package app.revanced.patches.backdrops.misc.pro.patch
+
+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.MethodFingerprintExtensions.name
+import app.revanced.patcher.extensions.addInstructions
+import app.revanced.patcher.extensions.instruction
+import app.revanced.patcher.patch.BytecodePatch
+import app.revanced.patcher.patch.PatchResult
+import app.revanced.patcher.patch.PatchResultError
+import app.revanced.patcher.patch.PatchResultSuccess
+import app.revanced.patcher.patch.annotations.Patch
+import app.revanced.patches.backdrops.misc.pro.annotations.ProUnlockCompatibility
+import app.revanced.patches.backdrops.misc.pro.fingerprints.ProUnlockFingerprint
+import org.jf.dexlib2.iface.instruction.OneRegisterInstruction
+
+@Patch
+@Name("pro-unlock")
+@Description("Unlocks pro-only functions.")
+@ProUnlockCompatibility
+@Version("0.0.1")
+class ProUnlockPatch : BytecodePatch(
+    listOf(ProUnlockFingerprint)
+) {
+    override fun execute(context: BytecodeContext): PatchResult {
+        val result = ProUnlockFingerprint.result ?: return PatchResultError("${ProUnlockFingerprint.name} not found")
+
+        val moveRegisterInstruction = result.mutableMethod.instruction(result.scanResult.patternScanResult!!.endIndex - 1)
+        val register = (moveRegisterInstruction as OneRegisterInstruction).registerA
+
+        result.mutableMethod.addInstructions(
+            result.scanResult.patternScanResult!!.endIndex,
+            """
+                const/4 v$register, 0x1
+            """
+        )
+
+        return PatchResultSuccess()
+    }
+}