/*
 * Copyright (c) 1998-2011 Caucho Technology -- all rights reserved
 *
 * This file is part of Resin(R) Open Source
 *
 * Each copy or derived work must preserve the copyright notice and this
 * notice unmodified.
 *
 * Resin Open Source is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * Resin Open Source is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE, or any warranty
 * of NON-INFRINGEMENT.  See the GNU General Public License for more
 * details.
 *
 * You should have received a copy of the GNU General Public License
 * along with Resin Open Source; if not, write to the
 *   Free SoftwareFoundation, Inc.
 *   59 Temple Place, Suite 330
 *   Boston, MA 02111-1307  USA
 *
 * @author Scott Ferguson
 */

package com.caucho.eswrap.java.io;

import com.caucho.util.CharBuffer;

import java.io.IOException;
import java.io.Reader;

public class ReaderEcmaWrap {
  public static int readByte(Reader is)
  throws IOException
  {
    return is.read();
  }

  public static String read(Reader is)
  throws IOException
  {
    int ch = is.read();

    if (ch == -1)
      return null;

    return String.valueOf((char) ch);
  }

  public static String read(Reader is, int length)
  throws IOException
  {
    CharBuffer bb = new CharBuffer();

    for (; length > 0; length--) {
      int ch = is.read();

      if (ch == -1)
        break;

      bb.append((char) ch);
    }

    if (bb.length() == 0)
      return null;

    return bb.toString();
  }

  public static String readln(Reader is)
  throws IOException
  {
    CharBuffer bb = new CharBuffer();

    boolean hasCr = false;
    boolean hasData = false;
    while (true) {
      int ch = is.read();

      if (ch == -1)
        break;
      else if (ch == '\n') {
        hasData = true;
        break;
      }
      else if (hasCr) {
        hasData = true;
        break;
      }

      if (ch == '\r')
        hasCr = true;
      else
        bb.append((char) ch);
    }

    if (bb.length() == 0 && ! hasData)
      return null;

    return bb.toString();
  }
}