Update the GodotHost interface to support signing and verifying Android apks

Update the export logic to enable apk generation and signing for Android editor builds

Note: Only legacy builds are supported. Gradle builds are not supported at this point in time.

platform/android/java/lib/src/org/godotengine/godot/Godot.kt

@@ -50,6 +50,7 @@ import androidx.core.view.ViewCompat
 import androidx.core.view.WindowInsetsAnimationCompat
 import androidx.core.view.WindowInsetsCompat
 import com.google.android.vending.expansion.downloader.*
+import org.godotengine.godot.error.Error
 import org.godotengine.godot.input.GodotEditText
 import org.godotengine.godot.input.GodotInputHandler
 import org.godotengine.godot.io.directory.DirectoryAccessHandler
@@ -96,7 +97,6 @@ class Godot(private val context: Context) {
 		fun isEditorBuild() = BuildConfig.FLAVOR == EDITOR_FLAVOR
 	}
 
-	private val windowManager: WindowManager = context.getSystemService(Context.WINDOW_SERVICE) as WindowManager
 	private val mSensorManager: SensorManager = context.getSystemService(Context.SENSOR_SERVICE) as SensorManager
 	private val mClipboard: ClipboardManager = context.getSystemService(Context.CLIPBOARD_SERVICE) as ClipboardManager
 	private val vibratorService: Vibrator = context.getSystemService(Context.VIBRATOR_SERVICE) as Vibrator
@@ -1054,4 +1054,20 @@ class Godot(private val context: Context) {
 	private fun nativeDumpBenchmark(benchmarkFile: String) {
 		dumpBenchmark(fileAccessHandler, benchmarkFile)
 	}
+
+	@Keep
+	private fun nativeSignApk(inputPath: String,
+							  outputPath: String,
+							  keystorePath: String,
+							  keystoreUser: String,
+							  keystorePassword: String): Int {
+		val signResult = primaryHost?.signApk(inputPath, outputPath, keystorePath, keystoreUser, keystorePassword) ?: Error.ERR_UNAVAILABLE
+		return signResult.toNativeValue()
+	}
+
+	@Keep
+	private fun nativeVerifyApk(apkPath: String): Int {
+		val verifyResult = primaryHost?.verifyApk(apkPath) ?: Error.ERR_UNAVAILABLE
+		return verifyResult.toNativeValue()
+	}
 }

platform/android/java/lib/src/org/godotengine/godot/GodotFragment.java

@@ -30,6 +30,7 @@
 
 package org.godotengine.godot;
 
+import org.godotengine.godot.error.Error;
 import org.godotengine.godot.plugin.GodotPlugin;
 import org.godotengine.godot.utils.BenchmarkUtils;
 
@@ -484,4 +485,20 @@ public class GodotFragment extends Fragment implements IDownloaderClient, GodotH
 		}
 		return Collections.emptySet();
 	}
+
+	@Override
+	public Error signApk(@NonNull String inputPath, @NonNull String outputPath, @NonNull String keystorePath, @NonNull String keystoreUser, @NonNull String keystorePassword) {
+		if (parentHost != null) {
+			return parentHost.signApk(inputPath, outputPath, keystorePath, keystoreUser, keystorePassword);
+		}
+		return Error.ERR_UNAVAILABLE;
+	}
+
+	@Override
+	public Error verifyApk(@NonNull String apkPath) {
+		if (parentHost != null) {
+			return parentHost.verifyApk(apkPath);
+		}
+		return Error.ERR_UNAVAILABLE;
+	}
 }

platform/android/java/lib/src/org/godotengine/godot/GodotHost.java

@@ -30,10 +30,13 @@
 
 package org.godotengine.godot;
 
+import org.godotengine.godot.error.Error;
 import org.godotengine.godot.plugin.GodotPlugin;
 
 import android.app.Activity;
 
+import androidx.annotation.NonNull;
+
 import java.util.Collections;
 import java.util.List;
 import java.util.Set;
@@ -108,4 +111,29 @@ public interface GodotHost {
 	default Set<GodotPlugin> getHostPlugins(Godot engine) {
 		return Collections.emptySet();
 	}
+
+	/**
+	 * Signs the given Android apk
+	 *
+	 * @param inputPath Path to the apk that should be signed
+	 * @param outputPath Path for the signed output apk; can be the same as inputPath
+	 * @param keystorePath Path to the keystore to use for signing the apk
+	 * @param keystoreUser Keystore user credential
+	 * @param keystorePassword Keystore password credential
+	 *
+	 * @return {@link Error#OK} if signing is successful
+	 */
+	default Error signApk(@NonNull String inputPath, @NonNull String outputPath, @NonNull String keystorePath, @NonNull String keystoreUser, @NonNull String keystorePassword) {
+		return Error.ERR_UNAVAILABLE;
+	}
+
+	/**
+	 * Verifies the given Android apk is signed
+	 *
+	 * @param apkPath Path to the apk that should be verified
+	 * @return {@link Error#OK} if verification was successful
+	 */
+	default Error verifyApk(@NonNull String apkPath) {
+		return Error.ERR_UNAVAILABLE;
+	}
 }

platform/android/java/lib/src/org/godotengine/godot/io/StorageScope.kt

@@ -73,6 +73,14 @@ internal enum class StorageScope {
 		private val downloadsSharedDir: String? = Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_DOWNLOADS).canonicalPath
 		private val documentsSharedDir: String? = Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_DOCUMENTS).canonicalPath
 
+		/**
+		 * Determine if the given path is accessible.
+		 */
+		fun canAccess(path: String?): Boolean {
+			val storageScope = identifyStorageScope(path)
+			return storageScope == APP || storageScope == SHARED
+		}
+
 		/**
 		 * Determines which [StorageScope] the given path falls under.
 		 */

platform/android/java/lib/src/org/godotengine/godot/io/file/FileAccessHandler.kt

@@ -107,7 +107,7 @@ class FileAccessHandler(val context: Context) {
 		}
 	}
 
-	private val storageScopeIdentifier = StorageScope.Identifier(context)
+	internal val storageScopeIdentifier = StorageScope.Identifier(context)
 	private val files = SparseArray<DataAccess>()
 	private var lastFileId = STARTING_FILE_ID