feat: Support patching APKM bundles (#40)

Author: prateek-who

build.gradle.kts

@@ -32,12 +32,33 @@ repositories {
     maven { url = uri("https://jitpack.io") }
 }
 
+val apkEditorLib by configurations.creating
+
+val strippedApkEditorLib by tasks.registering(org.gradle.jvm.tasks.Jar::class) {
+    archiveFileName.set("APKEditor-cli.jar")
+    duplicatesStrategy = DuplicatesStrategy.EXCLUDE
+    doFirst {
+        from(apkEditorLib.resolve().map { zipTree(it) })
+    }
+    exclude(
+        "org/xmlpull/**",
+        "antlr/**",
+        "org/antlr/**",
+        "com/beust/jcommander/**",
+        "javax/annotation/**",
+        "smali.properties",
+        "baksmali.properties"
+    )
+}
+
 dependencies {
     implementation(libs.morphe.patcher)
     implementation(libs.morphe.library)
     implementation(libs.kotlinx.coroutines.core)
     implementation(libs.kotlinx.serialization.json)
     implementation(libs.picocli)
+    apkEditorLib(files("$rootDir/libs/APKEditor-1.4.7.jar"))
+    implementation(files(strippedApkEditorLib))
 
     testImplementation(libs.kotlin.test)
 }
@@ -65,7 +86,11 @@ tasks {
     }
 
     shadowJar {
-        exclude("/prebuilt/linux/aapt", "/prebuilt/windows/aapt.exe", "/prebuilt/*/aapt_*")
+        exclude(
+            "/prebuilt/linux/aapt",
+            "/prebuilt/windows/aapt.exe",
+            "/prebuilt/*/aapt_*",
+        )
         minimize {
             exclude(dependency("org.bouncycastle:.*"))
             exclude(dependency("app.morphe:morphe-patcher"))

libs/APKEditor-1.4.7.jar

@@ -14,6 +14,8 @@ import app.morphe.patcher.Patcher
 import app.morphe.patcher.PatcherConfig
 import app.morphe.patcher.patch.Patch
 import app.morphe.patcher.patch.loadPatchesFromJar
+import com.reandroid.apkeditor.merge.Merger
+import com.reandroid.apkeditor.merge.MergerOptions
 import kotlinx.coroutines.runBlocking
 import kotlinx.serialization.ExperimentalSerializationApi
 import kotlinx.serialization.json.Json
@@ -260,7 +262,7 @@ internal object PatchCommand : Runnable {
 
         val outputFilePath =
             outputFilePath ?: File("").absoluteFile.resolve(
-                "${apk.nameWithoutExtension}-patched.${apk.extension}",
+                "${apk.nameWithoutExtension}-patched.apk",
             )
 
         val temporaryFilesPath =
@@ -312,12 +314,34 @@ internal object PatchCommand : Runnable {
 
         val patcherTemporaryFilesPath = temporaryFilesPath.resolve("patcher")
 
+        // Checking if the file is in apkm format (like reddit)
+        var mergedApkToCleanup: File? = null
+        val inputApk = if (apk.extension.equals("apkm", ignoreCase = true)) {
+            logger.info("Merging APKM bundle")
+
+            // Save merged APK to output directory (will be cleaned up after patching)
+            val outputApk = outputFilePath.parentFile.resolve("${apk.nameWithoutExtension}-merged.apk")
+
+            // Use APKEditor's Merger directly (handles extraction and merging)
+            val mergerOptions = MergerOptions().apply {
+                inputFile = apk  // Original APKM file
+                outputFile = outputApk
+                cleanMeta = true
+            }
+            Merger(mergerOptions).run()
+
+            mergedApkToCleanup = outputApk
+            outputApk
+        } else {
+            apk
+        }
+
         val patchingResult = PatchingResult()
 
         try {
             val (packageName, patcherResult) = Patcher(
                 PatcherConfig(
-                    apk,
+                    inputApk,
                     patcherTemporaryFilesPath,
                     aaptBinaryPath?.path,
                     patcherTemporaryFilesPath.absolutePath,
@@ -377,7 +401,7 @@ internal object PatchCommand : Runnable {
 
             // region Save.
 
-            apk.copyTo(temporaryFilesPath.resolve(apk.name), overwrite = true).apply {
+            inputApk.copyTo(temporaryFilesPath.resolve(inputApk.name), overwrite = true).apply {
                 patchingResult.addStepResult(
                     PatchingStep.REBUILDING,
                     {
@@ -406,6 +430,7 @@ internal object PatchCommand : Runnable {
                     patchedApkFile.copyTo(outputFilePath, overwrite = true)
                 }
             }
+
             logger.info("Saved to $outputFilePath")
 
             // endregion
@@ -448,6 +473,13 @@ internal object PatchCommand : Runnable {
             logger.info("Purging temporary files")
             purge(temporaryFilesPath)
         }
+
+        // Clean up merged APK if we created one from APKM
+        mergedApkToCleanup?.let {
+            if (!it.delete()) {
+                logger.warning("Could not clean up merged APK: ${it.path}")
+            }
+        }
     }
 
     /**