/*
 * Copyright (C) 2014-2015 Dominik Schürmann <dominik@dominikschuermann.de>
 *               2013 Florian Schmaus <flo@geekplace.eu>
 *
 * 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 org.openintents.openpgp.util;

import android.os.ParcelFileDescriptor;
import android.util.Log;

import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;

public class ParcelFileDescriptorUtil {

    public static ParcelFileDescriptor pipeFrom(InputStream inputStream)
            throws IOException {
        ParcelFileDescriptor[] pipe = ParcelFileDescriptor.createPipe();
        ParcelFileDescriptor readSide = pipe[0];
        ParcelFileDescriptor writeSide = pipe[1];

        new TransferThread(inputStream, new ParcelFileDescriptor.AutoCloseOutputStream(writeSide))
                .start();

        return readSide;
    }


    public static TransferThread pipeTo(OutputStream outputStream, ParcelFileDescriptor output)
            throws IOException {

        TransferThread t = new TransferThread(new ParcelFileDescriptor.AutoCloseInputStream(output), outputStream);

        t.start();
        return t;
    }


    static class TransferThread extends Thread {
        final InputStream mIn;
        final OutputStream mOut;

        TransferThread(InputStream in, OutputStream out) {
            super("IPC Transfer Thread");
            mIn = in;
            mOut = out;
            setDaemon(true);
        }

        @Override
        public void run() {
            byte[] buf = new byte[4096];
            int len;

            try {
                while ((len = mIn.read(buf)) > 0) {
                    mOut.write(buf, 0, len);
                }
            } catch (IOException e) {
                Log.e(OpenPgpApi.TAG, "IOException when writing to out", e);
            } finally {
                try {
                    mIn.close();
                } catch (IOException ignored) {
                }
                try {
                    mOut.close();
                } catch (IOException ignored) {
                }
            }
        }
    }

}
