From 61a7533136f38d7a308e31c9f250baad00515d6a Mon Sep 17 00:00:00 2001
From: Karol <karol.czeryna@gmail.com>
Date: Thu, 24 Aug 2023 22:21:33 +0200
Subject: [PATCH] feat(Duolingo): Add `Unlock Duolingo Super` patch (#2862)

---
 .../IsUserSuperMethodFingerprint.kt           | 14 ++++
 .../UserSerializationMethodFingerprint.kt     | 20 ++++++
 .../patch/UnlockDuolingoSuperPatch.kt         | 64 +++++++++++++++++++
 3 files changed, 98 insertions(+)
 create mode 100644 src/main/kotlin/app/revanced/patches/duolingo/unlocksuper/fingerprints/IsUserSuperMethodFingerprint.kt
 create mode 100644 src/main/kotlin/app/revanced/patches/duolingo/unlocksuper/fingerprints/UserSerializationMethodFingerprint.kt
 create mode 100644 src/main/kotlin/app/revanced/patches/duolingo/unlocksuper/patch/UnlockDuolingoSuperPatch.kt

diff --git a/src/main/kotlin/app/revanced/patches/duolingo/unlocksuper/fingerprints/IsUserSuperMethodFingerprint.kt b/src/main/kotlin/app/revanced/patches/duolingo/unlocksuper/fingerprints/IsUserSuperMethodFingerprint.kt
new file mode 100644
index 0000000000..8ee88fdcee
--- /dev/null
+++ b/src/main/kotlin/app/revanced/patches/duolingo/unlocksuper/fingerprints/IsUserSuperMethodFingerprint.kt
@@ -0,0 +1,14 @@
+package app.revanced.patches.duolingo.unlocksuper.fingerprints
+
+import app.revanced.patcher.extensions.or
+import app.revanced.patcher.fingerprint.method.impl.MethodFingerprint
+import com.android.tools.smali.dexlib2.AccessFlags
+import com.android.tools.smali.dexlib2.Opcode
+
+object IsUserSuperMethodFingerprint : MethodFingerprint(
+    returnType = "Ljava/lang/Object",
+    parameters = listOf("Ljava/lang/Object"),
+    accessFlags = AccessFlags.PUBLIC or AccessFlags.FINAL,
+    strings = listOf("user"),
+    opcodes = listOf(Opcode.IGET_BOOLEAN),
+)
\ No newline at end of file
diff --git a/src/main/kotlin/app/revanced/patches/duolingo/unlocksuper/fingerprints/UserSerializationMethodFingerprint.kt b/src/main/kotlin/app/revanced/patches/duolingo/unlocksuper/fingerprints/UserSerializationMethodFingerprint.kt
new file mode 100644
index 0000000000..2d8bcdda14
--- /dev/null
+++ b/src/main/kotlin/app/revanced/patches/duolingo/unlocksuper/fingerprints/UserSerializationMethodFingerprint.kt
@@ -0,0 +1,20 @@
+package app.revanced.patches.duolingo.unlocksuper.fingerprints
+
+import app.revanced.patcher.extensions.or
+import app.revanced.patcher.fingerprint.method.impl.MethodFingerprint
+import com.android.tools.smali.dexlib2.AccessFlags
+import com.android.tools.smali.dexlib2.Opcode
+
+object UserSerializationMethodFingerprint : MethodFingerprint(
+    returnType = "V",
+    accessFlags = AccessFlags.PUBLIC or AccessFlags.CONSTRUCTOR,
+    strings = listOf(
+        "betaStatus",
+        "coachOutfit",
+        "globalAmbassadorStatus",
+    ),
+    opcodes = listOf(
+        Opcode.MOVE_FROM16,
+        Opcode.IPUT_BOOLEAN,
+    ),
+)
\ No newline at end of file
diff --git a/src/main/kotlin/app/revanced/patches/duolingo/unlocksuper/patch/UnlockDuolingoSuperPatch.kt b/src/main/kotlin/app/revanced/patches/duolingo/unlocksuper/patch/UnlockDuolingoSuperPatch.kt
new file mode 100644
index 0000000000..86d2ecbc78
--- /dev/null
+++ b/src/main/kotlin/app/revanced/patches/duolingo/unlocksuper/patch/UnlockDuolingoSuperPatch.kt
@@ -0,0 +1,64 @@
+package app.revanced.patches.duolingo.unlocksuper.patch
+
+import app.revanced.extensions.toErrorResult
+import app.revanced.patcher.annotation.Compatibility
+import app.revanced.patcher.annotation.Description
+import app.revanced.patcher.annotation.Name
+import app.revanced.patcher.annotation.Package
+import app.revanced.patcher.data.BytecodeContext
+import app.revanced.patcher.extensions.InstructionExtensions.getInstructions
+import app.revanced.patcher.extensions.InstructionExtensions.replaceInstructions
+import app.revanced.patcher.patch.BytecodePatch
+import app.revanced.patcher.patch.PatchException
+import app.revanced.patcher.patch.annotations.Patch
+import app.revanced.patcher.util.proxy.mutableTypes.MutableMethod
+import app.revanced.patches.duolingo.unlocksuper.fingerprints.IsUserSuperMethodFingerprint
+import app.revanced.patches.duolingo.unlocksuper.fingerprints.UserSerializationMethodFingerprint
+import com.android.tools.smali.dexlib2.Opcode
+import com.android.tools.smali.dexlib2.builder.instruction.BuilderInstruction22c
+import com.android.tools.smali.dexlib2.iface.reference.Reference
+
+@Patch
+@Name("Unlock Duolingo Super")
+@Description("Unlocks Duolingo Super features.")
+@Compatibility([Package("com.duolingo")])
+class UnlockDuolingoSuperPatch : BytecodePatch(
+    listOf(UserSerializationMethodFingerprint, IsUserSuperMethodFingerprint)
+) {
+
+    /* First find the reference to the isUserSuper field, then patch the instruction that assigns it to false.
+    * This strategy is used because the method that sets the isUserSuper field is difficult to fingerprint reliably.
+    */
+    override fun execute(context: BytecodeContext) {
+        // Find the reference to the isUserSuper field.
+        val isUserSuperReference = IsUserSuperMethodFingerprint
+            .result
+            ?.mutableMethod
+            ?.getInstructions()
+            ?.filterIsInstance<BuilderInstruction22c>()
+            ?.firstOrNull { it.opcode == Opcode.IGET_BOOLEAN }
+            ?.reference
+            ?: throw IsUserSuperMethodFingerprint.toErrorResult()
+
+        // Patch the instruction that assigns isUserSuper to true.
+        UserSerializationMethodFingerprint
+            .result
+            ?.mutableMethod
+            ?.apply {
+                replaceInstructions(
+                    indexOfReference(isUserSuperReference) - 1,
+                    "const/4 v2, 0x1"
+                )
+            }
+            ?: throw UserSerializationMethodFingerprint.toErrorResult()
+    }
+
+    private companion object {
+        private fun MutableMethod.indexOfReference(reference: Reference) = getInstructions()
+            .filterIsInstance<BuilderInstruction22c>()
+            .filter { it.opcode == Opcode.IPUT_BOOLEAN }.indexOfFirst { it.reference == reference }.let {
+                if (it == -1) throw PatchException("Could not find index of instruction with supplied reference.")
+                else it
+            }
+    }
+}
\ No newline at end of file