package com.github.davidmoten.rx2.internal.flowable.buffertofile;
   
   import java.io.File;
   import java.util.Arrays;
   
   public final class Page {
   
       private static final boolean debug = false;
   
      private final int pageSize;
      private final MemoryMappedFile mm;
  
      public Page(File file, int pageSize) {
          this.pageSize = pageSize;
          this.mm = new MemoryMappedFile(file, pageSize);
      }
  
      public int length() {
          return pageSize;
      }
  
      public void put(int position, byte[] bytes, int start, int length) {
          if (debug)
              println("put at " + this.hashCode() + ":" + position + " of "
                      + Arrays.toString(Arrays.copyOfRange(bytes, start, start + length)));
          mm.putBytes(position, bytes, start, length);
      }
  
      public void putIntOrdered(int writePosition, int value) {
          if (debug)
              println("putIntOrdered at " + this.hashCode() + ":" + writePosition + " of " + value);
          mm.putOrderedInt(writePosition, value);
      }
  
      public void putInt(int writePosition, int value) {
          if (debug)
              println("putInt at " + this.hashCode() + ":" + writePosition + " of " + value);
          mm.putInt(writePosition, value);
      }
  
      public void get(byte[] dst, int offset, int readPosition, int length) {
          if (debug)
              println("getting at " + this.hashCode() + ":" + readPosition + " length=" + length);
          mm.getBytes(readPosition, dst, offset, length);
      }
  
      public int getIntVolatile(int readPosition) {
          int n = mm.getIntVolatile(readPosition);
          if (debug)
              println("getting int volatile at " + this.hashCode() + ":" + readPosition + "=" + n);
          return n;
      }
  
      public void close() {
          mm.close();
      }
  
      static void println(String s) {
          System.out.println(Thread.currentThread().getName() + ": " + s);
      }
  
      public int avail(int position) {
          return pageSize - position;
      }
  
      public int getInt(int readPosition) {
          return mm.getInt(readPosition);
      }
  
      public void putByte(int currentWritePosition, byte b) {
          mm.putByte(currentWritePosition, b);
      }
  
      public byte getByte(int readPosition) {
          return mm.getByte(readPosition);
      }
  }