package org.armedbear.lisp.util;

import java.io.*;
import java.util.*;

import junit.framework.*;

public class RACFTest extends TestCase {

  public RACFTest(String name) {
    super(name);
  }

//  public void test1() throws Exception {
//    RandomAccessCharacterFile f = new RandomAccessCharacterFile(
//                                    new RandomAccessFile(new File("test.dat"),
//                                                         "rw"),
//                                    null);
//    try {
//      InputStream in = f.getInputStream();
//      OutputStream out = f.getOutputStream();
//      out.write('a');
//      f.position(0);
//      
//      assertEquals('a', (char) in.read());
////      in.read(); //passes if you do this
//      
//      //alt
////      byte[] buf = new byte[1]; //passes if len is 2
////      assertEquals(1, in.read(buf));
////      assertEquals('a', (char)buf[0]);
//      
//      assertEquals(1, f.position());
//      out.write('b');
//      assertEquals(2, f.position());
//    } finally {
//      f.close();
//    }
//  }

  public void test2() throws Exception {
    RandomAccessCharacterFile f = openRacf("test.dat");
    try {
      write(f, 'a');
      f.position(0);
      
      byte[] buf = new byte[1]; //passes if len is 2
      assertEquals(1, f.read(buf, 0, buf.length));
      assertEquals('a', (char)buf[0]);
      
      assertEquals(1, f.position());
      write(f, 'b');
      assertEquals(2, f.position());
    } finally {
      f.close();
    }
  }

  private RandomAccessCharacterFile openRacf(String name) throws IOException,
      FileNotFoundException {
    return new RandomAccessCharacterFile(
                                    new RandomAccessFile(new File(name),
                                                         "rw"),
                                    null);
  }

  void write(RandomAccessCharacterFile f, char c) throws IOException {
    byte[] buf = new byte[1];
    buf[0] = (byte) c;
    f.write(buf, 0, buf.length);
  }

  public void test3() throws Exception {
    int iters = 1500;
    int arraySize = 1025;
    byte[] b = new byte[arraySize];
    Random rand = new Random();
    RandomAccessCharacterFile f = openRacf("test3.dat");
    byte[] buf = new byte[1];
    for(int i = 0; i < iters; i++) {
      int nbytes = rand.nextInt(arraySize);
      if (rand.nextInt(2) == 0 || f.length() == 0) {
        long before = f.length();
        f.position(before);
        write2(f, b, 0, nbytes);
//        f.flushBbuf(false); //on ABCL, don't need this before file-length
        assertEquals("iter " + i, nbytes, f.length() - before);
      } else {
        f.position(rand.nextInt((int) f.length()));
        f.read(buf, 0, buf.length);
      }
    }
  }

  private void write2(RandomAccessCharacterFile f, byte[] b, int offset,
      int len) throws IOException {
    f.write(b, offset, len);
  }

}