post-install Intent to tell OsmAnd to import "installed" OBF

OsmAnd will import map files from a file:// URL pointing to an OBF file,
but this currently only works for file:// and not the proper content://.
This uses a hack to disable the warning about file:// URIs but only for the
final stage of installing the .obf file.

Hopefully in the future, this can be changed to use a proper content:// URL
as I suggested to them in this merge request:
https://github.com/osmandapp/OsmAnd/pull/10043

app/src/main/java/org/fdroid/fdroid/data/Apk.java

@@ -569,12 +569,15 @@ public class Apk extends ValueObject implements Comparable<Apk>, Parcelable {
         String fileExtension = MimeTypeMap.getFileExtensionFromUrl(this.getCanonicalUrl());
         if (TextUtils.isEmpty(fileExtension)) return path;
         MimeTypeMap mimeTypeMap = MimeTypeMap.getSingleton();
-        String[] mimeType = mimeTypeMap.getMimeTypeFromExtension(fileExtension).split("/");
+        String mimeType = mimeTypeMap.getMimeTypeFromExtension(fileExtension);
-        String topLevelType;
+        String topLevelType = null;
-        if (mimeType.length == 0) {
+        if (!TextUtils.isEmpty(mimeType)) {
+            String[] mimeTypeSections = mimeType.split("/");
+            if (mimeTypeSections.length == 0) {
                 topLevelType = "";
             } else {
-            topLevelType = mimeType[0];
+                topLevelType = mimeTypeSections[0];
+            }
         }
         if ("audio".equals(topLevelType)) {
             path = Environment.getExternalStoragePublicDirectory(

app/src/main/java/org/fdroid/fdroid/installer/FileInstallerActivity.java

@@ -5,8 +5,12 @@ import android.content.DialogInterface;
 import android.content.Intent;
 import android.content.pm.PackageManager;
 import android.net.Uri;
+import android.os.Build;
 import android.os.Bundle;
+import android.os.StrictMode;
+import android.util.Log;
 import android.view.ContextThemeWrapper;
+import android.webkit.MimeTypeMap;
 import android.widget.Toast;
 import androidx.annotation.NonNull;
 import androidx.appcompat.app.AlertDialog;
@@ -21,6 +25,7 @@ import org.fdroid.fdroid.data.Apk;
 
 import java.io.File;
 import java.io.IOException;
+import java.lang.reflect.Method;
 
 public class FileInstallerActivity extends FragmentActivity {
 
@@ -161,12 +166,44 @@ public class FileInstallerActivity extends FragmentActivity {
             Toast.makeText(this, String.format(this.getString(R.string.app_installed_media), path.toString()),
                     Toast.LENGTH_LONG).show();
             installer.sendBroadcastInstall(canonicalUri, Installer.ACTION_INSTALL_COMPLETE);
+            postInstall(path);
         } else {
             installer.sendBroadcastInstall(canonicalUri, Installer.ACTION_INSTALL_INTERRUPTED);
         }
         finish();
     }
 
+    /**
+     * Run any file-type-specific processes after the file has been copied into place.
+     * <p>
+     * When this was written, OsmAnd only supported importing OBF files via a
+     * {@code file:///} URL, so this disables {@link android.os.FileUriExposedException}.
+     */
+    private void postInstall(File path) {
+        if (path.getName().endsWith(".obf")) {
+            if (Build.VERSION.SDK_INT >= 24) {
+                try {
+                    Method m = StrictMode.class.getMethod("disableDeathOnFileUriExposure");
+                    m.invoke(null);
+                } catch (Exception e) {
+                    e.printStackTrace();
+                }
+            }
+            Intent intent = new Intent(Intent.ACTION_VIEW);
+            intent.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP | Intent.FLAG_ACTIVITY_NEW_TASK);
+            String mimeType = MimeTypeMap.getSingleton().getMimeTypeFromExtension("obf");
+            intent.setDataAndType(Uri.fromFile(path), mimeType);
+            if (Build.VERSION.SDK_INT >= 23) {
+                intent.addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION);
+            }
+            if (intent.resolveActivity(getPackageManager()) != null) {
+                startActivity(intent);
+            } else {
+                Log.i(TAG, "No Activity available to handle " + intent);
+            }
+        }
+    }
+
     private void uninstallPackage(Apk apk) {
         if (apk.isMediaInstalled(activity.getApplicationContext())) {
             File file = apk.getInstalledMediaFile(activity.getApplicationContext());

app/src/test/java/org/fdroid/fdroid/data/ApkTest.java

@@ -2,7 +2,6 @@ package org.fdroid.fdroid.data;
 
 import android.content.ContextWrapper;
 import android.os.Environment;
-import android.util.Log;
 import android.webkit.MimeTypeMap;
 import androidx.test.core.app.ApplicationProvider;
 import org.apache.commons.io.FileUtils;
@@ -58,6 +57,16 @@ public class ApkTest {
         assertEquals(new File(context.getApplicationInfo().dataDir + "/ota"), path);
     }
 
+    @Test
+    public void testGetMediaInstallPathWithObf() {
+        Apk apk = new Apk();
+        apk.apkName = "Norway_bouvet_europe_2.obf";
+        apk.repoAddress = "https://example.com/fdroid/repo";
+        assertFalse(apk.isApk());
+        File path = apk.getMediaInstallPath(context);
+        assertEquals(Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_DOWNLOADS), path);
+    }
+
     @Test
     public void testGetMediaInstallPathWithObfZip() throws IOException {
         Apk apk = new Apk();

app/src/test/java/org/fdroid/fdroid/installer/ApkCacheTest.java

@@ -54,5 +54,9 @@ public class ApkCacheTest {
                 new File(cacheDir, "example.com--1/Norway_bouvet_europe_2.obf.zip"),
                 ApkCache.getApkDownloadPath(context,
                         "https://example.com/fdroid/repo/Norway_bouvet_europe_2.obf.zip"));
+        assertEquals("Should work for OBF files also",
+                new File(cacheDir, "example.com--1/Norway_bouvet_europe_2.obf"),
+                ApkCache.getApkDownloadPath(context,
+                        "https://example.com/fdroid/repo/Norway_bouvet_europe_2.obf"));
     }
 }