/*
 *  Licensed to the Apache Software Foundation (ASF) under one
 *  or more contributor license agreements.  See the NOTICE file
 *  distributed with this work for additional information
 *  regarding copyright ownership.  The ASF licenses this file
 *  to you 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.apache.synapse.util;

import java.io.ByteArrayInputStream;
import java.io.DataInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.Arrays;
import java.util.Random;

import org.apache.axiom.util.blob.OverflowBlob;
import org.apache.commons.io.IOUtils;

import junit.framework.TestCase;

public class TemporaryDataTest extends TestCase {
    private final static Random random = new Random();
    
    private void doTestRandomReadWrite(int size) throws IOException {
        byte[] data = new byte[size];
        random.nextBytes(data);
        OverflowBlob tmp = new OverflowBlob(16, 1024, "test", ".dat");
        try {
            OutputStream out = tmp.getOutputStream();
            // Write the test data in chunks with random size
            int offset = 0;
            while (offset < data.length) {
                int c = Math.min(512 + random.nextInt(1024), data.length - offset);
                out.write(data, offset, c);
                offset += c;
            }
            out.close();
            assertEquals(size, tmp.getLength());
            // Reread the test data, again in chunks with random size
            InputStream in = tmp.getInputStream();
            offset = 0;
            byte[] data2 = new byte[data.length];
            byte[] buffer = new byte[2048];
            while (true) {
                int bufferOffset = random.nextInt(512);
                int c = 512 + random.nextInt(1024);
                int read = in.read(buffer, bufferOffset, c);
                if (read == -1) {
                    break;
                }
                int newOffset = offset + read;
                assertTrue(newOffset <= data2.length);
                System.arraycopy(buffer, bufferOffset, data2, offset, read);
                offset = newOffset;
            }
            assertEquals(data2.length, offset);
            in.close();
            assertTrue(Arrays.equals(data, data2));
        }
        finally {
            tmp.release();
        }
    }
    
    public void testRandomReadWriteInMemory() throws IOException {
        doTestRandomReadWrite(10000);
    }
    
    public void testRandomReadWriteWithTemporaryFile() throws IOException {
        doTestRandomReadWrite(100000);
    }
    
    public void testMarkReset() throws IOException {
        byte[] sourceData1 = new byte[2000];
        byte[] sourceData2 = new byte[2000];
        random.nextBytes(sourceData1);
        random.nextBytes(sourceData2);
        OverflowBlob tmp = new OverflowBlob(16, 512, "test", ".dat");
        OutputStream out = tmp.getOutputStream();
        out.write(sourceData1);
        out.write(sourceData2);
        out.close();
        DataInputStream in = new DataInputStream(tmp.getInputStream());
        byte[] data1 = new byte[sourceData1.length];
        byte[] data2 = new byte[sourceData2.length];
        in.readFully(data1);
        in.mark(sourceData2.length);
        in.readFully(data2);
        in.reset();
        in.readFully(data2);
        assertTrue(Arrays.equals(sourceData1, data1));
        assertTrue(Arrays.equals(sourceData2, data2));
    }
    
    private void testReadFrom(int size) throws IOException {
        byte[] data = new byte[size];
        random.nextBytes(data);
        OverflowBlob tmp = new OverflowBlob(16, 1024, "test", ".dat");
        try {
            tmp.readFrom(new ByteArrayInputStream(data), -1);
            InputStream in = tmp.getInputStream();
            try {
                assertTrue(Arrays.equals(data, IOUtils.toByteArray(in)));
            }
            finally {
                in.close();
            }
        }
        finally {
            tmp.release();
        }
    }
    
    public void testReadFromInMemory() throws IOException {
        testReadFrom(10000);
    }
    
    public void testReadFromWithTemporaryFile() throws IOException {
        testReadFrom(100000);
    }
}