Create new settings category: Backup and restore

Following settings have been move to the new category:
- import database (from ContenttSettings)
- export database (from ContenttSettings)
- reset settings (from DebugSettings)

app/src/main/java/org/schabi/newpipe/settings/BackupRestoreSettingsFragment.java

@@ -0,0 +1,271 @@
+package org.schabi.newpipe.settings;
+
+import static org.schabi.newpipe.extractor.utils.Utils.isBlank;
+import static org.schabi.newpipe.util.Localization.assureCorrectAppLanguage;
+
+import android.app.Activity;
+import android.app.AlertDialog;
+import android.content.Context;
+import android.content.Intent;
+import android.content.SharedPreferences;
+import android.net.Uri;
+import android.os.Bundle;
+import android.widget.Toast;
+
+import androidx.activity.result.ActivityResult;
+import androidx.activity.result.ActivityResultLauncher;
+import androidx.activity.result.contract.ActivityResultContracts;
+import androidx.annotation.NonNull;
+import androidx.annotation.Nullable;
+import androidx.core.content.ContextCompat;
+import androidx.preference.Preference;
+import androidx.preference.PreferenceManager;
+
+import org.schabi.newpipe.NewPipeDatabase;
+import org.schabi.newpipe.R;
+import org.schabi.newpipe.error.ErrorUtil;
+import org.schabi.newpipe.streams.io.NoFileManagerSafeGuard;
+import org.schabi.newpipe.streams.io.StoredFileHelper;
+import org.schabi.newpipe.util.NavigationHelper;
+import org.schabi.newpipe.util.ZipHelper;
+
+import java.io.File;
+import java.io.IOException;
+import java.text.SimpleDateFormat;
+import java.util.Date;
+import java.util.Locale;
+import java.util.Objects;
+
+public class BackupRestoreSettingsFragment extends BasePreferenceFragment {
+
+    private static final String ZIP_MIME_TYPE = "application/zip";
+
+    private final SimpleDateFormat exportDateFormat =
+            new SimpleDateFormat("yyyyMMdd_HHmmss", Locale.US);
+    private ContentSettingsManager manager;
+    private String importExportDataPathKey;
+    private final ActivityResultLauncher<Intent> requestImportPathLauncher =
+            registerForActivityResult(new ActivityResultContracts.StartActivityForResult(),
+                    this::requestImportPathResult);
+    private final ActivityResultLauncher<Intent> requestExportPathLauncher =
+            registerForActivityResult(new ActivityResultContracts.StartActivityForResult(),
+                    this::requestExportPathResult);
+
+
+    @Override
+    public void onCreatePreferences(@Nullable final Bundle savedInstanceState,
+                                    @Nullable final String rootKey) {
+        final File homeDir = ContextCompat.getDataDir(requireContext());
+        Objects.requireNonNull(homeDir);
+        manager = new ContentSettingsManager(new NewPipeFileLocator(homeDir));
+        manager.deleteSettingsFile();
+
+        importExportDataPathKey = getString(R.string.import_export_data_path);
+
+
+        addPreferencesFromResourceRegistry();
+
+        final Preference importDataPreference = requirePreference(R.string.import_data);
+        importDataPreference.setOnPreferenceClickListener((Preference p) -> {
+            NoFileManagerSafeGuard.launchSafe(
+                    requestImportPathLauncher,
+                    StoredFileHelper.getPicker(requireContext(),
+                            ZIP_MIME_TYPE, getImportExportDataUri()),
+                    TAG,
+                    getContext()
+            );
+
+            return true;
+        });
+
+        final Preference exportDataPreference = requirePreference(R.string.export_data);
+        exportDataPreference.setOnPreferenceClickListener((final Preference p) -> {
+            NoFileManagerSafeGuard.launchSafe(
+                    requestExportPathLauncher,
+                    StoredFileHelper.getNewPicker(requireContext(),
+                            "NewPipeData-" + exportDateFormat.format(new Date()) + ".zip",
+                            ZIP_MIME_TYPE, getImportExportDataUri()),
+                    TAG,
+                    getContext()
+            );
+
+            return true;
+        });
+
+        final Preference resetSettings = findPreference(getString(R.string.reset_settings));
+        // Resets all settings by deleting shared preference and restarting the app
+        // A dialogue will pop up to confirm if user intends to reset all settings
+        assert resetSettings != null;
+        resetSettings.setOnPreferenceClickListener(preference -> {
+            // Show Alert Dialogue
+            final AlertDialog.Builder builder = new AlertDialog.Builder(getContext());
+            builder.setMessage(R.string.reset_all_settings);
+            builder.setCancelable(true);
+            builder.setPositiveButton(R.string.ok, (dialogInterface, i) -> {
+                // Deletes all shared preferences xml files.
+                final SharedPreferences sharedPreferences =
+                        PreferenceManager.getDefaultSharedPreferences(requireContext());
+                sharedPreferences.edit().clear().apply();
+                // Restarts the app
+                if (getActivity() == null) {
+                    return;
+                }
+                NavigationHelper.restartApp(getActivity());
+            });
+            builder.setNegativeButton(R.string.cancel, (dialogInterface, i) -> {
+            });
+            final AlertDialog alertDialog = builder.create();
+            alertDialog.show();
+            return true;
+        });
+    }
+
+    private void requestExportPathResult(final ActivityResult result) {
+        assureCorrectAppLanguage(requireContext());
+        if (result.getResultCode() == Activity.RESULT_OK && result.getData() != null) {
+            // will be saved only on success
+            final Uri lastExportDataUri = result.getData().getData();
+
+            final StoredFileHelper file = new StoredFileHelper(
+                    requireContext(), result.getData().getData(), ZIP_MIME_TYPE);
+
+            exportDatabase(file, lastExportDataUri);
+        }
+    }
+
+    private void requestImportPathResult(final ActivityResult result) {
+        assureCorrectAppLanguage(requireContext());
+        if (result.getResultCode() == Activity.RESULT_OK && result.getData() != null) {
+            // will be saved only on success
+            final Uri lastImportDataUri = result.getData().getData();
+
+            final StoredFileHelper file = new StoredFileHelper(
+                    requireContext(), result.getData().getData(), ZIP_MIME_TYPE);
+
+            new androidx.appcompat.app.AlertDialog.Builder(requireActivity())
+                    .setMessage(R.string.override_current_data)
+                    .setPositiveButton(R.string.ok, (d, id) ->
+                            importDatabase(file, lastImportDataUri))
+                    .setNegativeButton(R.string.cancel, (d, id) ->
+                            d.cancel())
+                    .show();
+        }
+    }
+
+    private void exportDatabase(final StoredFileHelper file, final Uri exportDataUri) {
+        try {
+            //checkpoint before export
+            NewPipeDatabase.checkpoint();
+
+            final SharedPreferences preferences = PreferenceManager
+                    .getDefaultSharedPreferences(requireContext());
+            manager.exportDatabase(preferences, file);
+
+            saveLastImportExportDataUri(exportDataUri); // save export path only on success
+            Toast.makeText(requireContext(), R.string.export_complete_toast, Toast.LENGTH_SHORT)
+                    .show();
+        } catch (final Exception e) {
+            ErrorUtil.showUiErrorSnackbar(this, "Exporting database", e);
+        }
+    }
+
+    private void importDatabase(final StoredFileHelper file, final Uri importDataUri) {
+        // check if file is supported
+        if (!ZipHelper.isValidZipFile(file)) {
+            Toast.makeText(requireContext(), R.string.no_valid_zip_file, Toast.LENGTH_SHORT)
+                    .show();
+            return;
+        }
+
+        try {
+            if (!manager.ensureDbDirectoryExists()) {
+                throw new IOException("Could not create databases dir");
+            }
+
+            if (!manager.extractDb(file)) {
+                Toast.makeText(requireContext(), R.string.could_not_import_all_files,
+                                Toast.LENGTH_LONG)
+                        .show();
+            }
+
+            // if settings file exist, ask if it should be imported.
+            if (manager.extractSettings(file)) {
+                new androidx.appcompat.app.AlertDialog.Builder(requireContext())
+                        .setTitle(R.string.import_settings)
+                        .setNegativeButton(R.string.cancel, (dialog, which) -> {
+                            dialog.dismiss();
+                            finishImport(importDataUri);
+                        })
+                        .setPositiveButton(R.string.ok, (dialog, which) -> {
+                            dialog.dismiss();
+                            final Context context = requireContext();
+                            final SharedPreferences prefs = PreferenceManager
+                                    .getDefaultSharedPreferences(context);
+                            manager.loadSharedPreferences(prefs);
+                            cleanImport(context, prefs);
+                            finishImport(importDataUri);
+                        })
+                        .show();
+            } else {
+                finishImport(importDataUri);
+            }
+        } catch (final Exception e) {
+            ErrorUtil.showUiErrorSnackbar(this, "Importing database", e);
+        }
+    }
+
+    /**
+     * Remove settings that are not supposed to be imported on different devices
+     * and reset them to default values.
+     * @param context the context used for the import
+     * @param prefs the preferences used while running the import
+     */
+    private void cleanImport(@NonNull final Context context,
+                             @NonNull final SharedPreferences prefs) {
+        // Check if media tunnelling needs to be disabled automatically,
+        // if it was disabled automatically in the imported preferences.
+        final String tunnelingKey = context.getString(R.string.disable_media_tunneling_key);
+        final String automaticTunnelingKey =
+                context.getString(R.string.disabled_media_tunneling_automatically_key);
+        // R.string.disable_media_tunneling_key should always be true
+        // if R.string.disabled_media_tunneling_automatically_key equals 1,
+        // but we double check here just to be sure and to avoid regressions
+        // caused by possible later modification of the media tunneling functionality.
+        // R.string.disabled_media_tunneling_automatically_key == 0:
+        //     automatic value overridden by user in settings
+        // R.string.disabled_media_tunneling_automatically_key == -1: not set
+        final boolean wasMediaTunnelingDisabledAutomatically =
+                prefs.getInt(automaticTunnelingKey, -1) == 1
+                        && prefs.getBoolean(tunnelingKey, false);
+        if (wasMediaTunnelingDisabledAutomatically) {
+            prefs.edit()
+                    .putInt(automaticTunnelingKey, -1)
+                    .putBoolean(tunnelingKey, false)
+                    .apply();
+            NewPipeSettings.setMediaTunneling(context);
+        }
+    }
+
+    /**
+     * Save import path and restart system.
+     *
+     * @param importDataUri The import path to save
+     */
+    private void finishImport(final Uri importDataUri) {
+        // save import path only on success
+        saveLastImportExportDataUri(importDataUri);
+        // restart app to properly load db
+        NavigationHelper.restartApp(requireActivity());
+    }
+
+    private Uri getImportExportDataUri() {
+        final String path = defaultPreferences.getString(importExportDataPathKey, null);
+        return isBlank(path) ? null : Uri.parse(path);
+    }
+
+    private void saveLastImportExportDataUri(final Uri importExportDataUri) {
+        final SharedPreferences.Editor editor = defaultPreferences.edit()
+                .putString(importExportDataPathKey, importExportDataUri.toString());
+        editor.apply();
+    }
+}