DeleteOperation.java

/*
 * Copyright 2014 Yaroslav Mytkalyk
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package com.docd.purefm.operations;

import android.content.Context;
import android.util.Log;

import com.docd.purefm.Environment;
import com.docd.purefm.commandline.CommandLine;
import com.docd.purefm.commandline.CommandRemove;
import com.docd.purefm.commandline.ShellHolder;
import com.docd.purefm.file.CommandLineFile;
import com.docd.purefm.file.FileObserverNotifier;
import com.docd.purefm.file.GenericFile;
import com.docd.purefm.settings.Settings;
import com.docd.purefm.utils.MediaStoreUtils;
import com.stericson.RootTools.RootTools;

import android.support.annotation.NonNull;

import java.io.File;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.HashSet;
import java.util.LinkedList;
import java.util.List;

/**
 * Operation that performs files deletion
 *
 * @author Doctoror
 */
final class DeleteOperation extends Operation<GenericFile, ArrayList<GenericFile>> {

    @NonNull
    private final Context mContext;

    DeleteOperation(@NonNull final Context context) {
        mContext = context;
    }

    @Override
    protected ArrayList<GenericFile> doInBackground(@NonNull final GenericFile... files) {
        final ArrayList<GenericFile> failed = new ArrayList<>();
        final List<GenericFile> filesAffected = new LinkedList<>();

        final Settings settings = Settings.getInstance(mContext);
        if (files[0] instanceof CommandLineFile) {
            if (!ShellHolder.getInstance().hasShell()) {
                Log.w("DeleteOperation", "No shell, aborting");
                failed.addAll(Arrays.asList(files));
                return failed;
            }

            final HashSet<String> remountPaths = new HashSet<>();
            // find paths to remount as read-write
            if (settings.useCommandLine() && settings.isSuEnabled()) {
                for (GenericFile file : files) {
                    try {
                        file = file.getCanonicalFile();
                    } catch (IOException e) {
                        e.printStackTrace();
                    }
                    final String parent = file.getParent();
                    if (parent != null) {
                        if (Environment.needsRemount(parent)) {
                            remountPaths.add(parent);
                        }
                    } else if (Environment.needsRemount(file.getAbsolutePath())) {
                        remountPaths.add(file.getAbsolutePath());
                    }
                }
            }
            for (final String remountPath : remountPaths) {
                RootTools.remount(remountPath, "RW");
            }

            try {
                for (final GenericFile file : files) {
                    if (isCanceled()) {
                        break;
                    }
                    final File fileFile = file.toFile();
                    if (CommandLine.execute(new CommandRemove(fileFile))) {
                        filesAffected.add(file);
                    } else {
                        failed.add(file);
                    }
                }
            } finally {
                for (final String remountPath : remountPaths) {
                    RootTools.remount(remountPath, "RO");
                }
                postProcess(filesAffected);
            }

        } else {
            try {
                for (final GenericFile file : files) {
                    if (isCanceled()) {
                        break;
                    }
                    if (file.delete()) {
                        filesAffected.add(file);
                    } else {
                        failed.add(file);
                    }
                }
            } finally {
                postProcess(filesAffected);
            }
        }
        return failed;
    }

    private void postProcess(@NonNull final List<GenericFile> filesDeleted) {
        if (!filesDeleted.isEmpty()) {
            MediaStoreUtils.deleteFilesOrDirectories(mContext.getContentResolver(), filesDeleted);
            FileObserverNotifier.notifyDeleted(filesDeleted);
        }
    }
}