/**
 * $Id: $
 * $Date: $
 *
 */

package org.xmlsh.sh.core;

import java.io.IOException;
import java.io.PrintWriter;
import java.io.StringWriter;
import java.util.ArrayList;
import java.util.List;
import org.apache.logging.log4j.LogManager;
import org.xmlsh.core.CoreException;
import org.xmlsh.core.EvalEnv;
import org.xmlsh.core.XValue;
import org.xmlsh.sh.grammar.Token;
import org.xmlsh.sh.shell.ParseResult;
import org.xmlsh.sh.shell.Shell;
import org.xmlsh.util.Util;

/*
 * A Value that evaulates to a "cmd_word" which is either a simple string,
 * or a subprocess expression
 * 
 */
public abstract class Word {

  private Token mFirstToken;

  public abstract void print(PrintWriter out);

  static org.apache.logging.log4j.Logger mLogger = LogManager.getLogger();

  /*
   * protected Word() {
   * mFirst = null ;
   * }
   */
  protected Word(Token t) {
    mFirstToken = t;

  }

  public boolean isJoinable() {
    return mFirstToken != null &&
        mFirstToken.specialToken == null &&
        !isDelim();

  }

  // Expand a word into an existing result class
  protected abstract ParseResult expandToResult(Shell shell, EvalEnv env,
      ParseResult result) throws IOException, CoreException;

  public final XValue expand(Shell shell, EvalEnv env)
      throws IOException, CoreException {

    mLogger.entry(shell, env);
    ParseResult result = new ParseResult();
    env = evalEnv(env);
    expandToResult(shell, env, result);
    return mLogger.exit(EvalUtils.expandResultToValue(shell, result, env));

  }

  public String expandString(Shell shell, EvalEnv env)
      throws IOException, CoreException {
    mLogger.entry(shell, env);

    env = evalEnv(env);
    return mLogger.exit(expand(shell, env).toString());
  }

  public List<XValue> expandToList(Shell shell, EvalEnv env)
      throws IOException, CoreException {

    mLogger.entry(shell, env);
    env = evalEnv(env);
    XValue v = expand(shell, env);
    List<XValue> list = new ArrayList<XValue>(1);
    if(v != null && !v.isNull())
      list.add(v);
    if(env.expandSequences())
      list = Util.expandSequences(list);
    return mLogger.exit(list);

  }

  public abstract boolean isEmpty();

  @Override
  public String toString() {

    StringWriter sw;
    PrintWriter w = new PrintWriter(sw = new StringWriter());
    print(w);
    w.close();
    return sw.toString();
  }

  public EvalEnv evalEnv(EvalEnv parent) {
    return parent;
  }

  abstract String getSimpleName();

  public boolean isDelim() {
    return false;
  }

  /**
   * @return the first
   */
  public Token getFirstToken() {
    return mFirstToken;
  }

  /**
   * @param first
   *          the first to set
   */
  public void setFirstToken(Token first) {
    mFirstToken = first;
  }

}

//
//
// Copyright (C) 2008-2014 David A. Lee.
//
// The contents of this file are subject to the "Simplified BSD License" (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.opensource.org/licenses/bsd-license.php
//
// Software distributed under the License is distributed on an "AS IS" basis,
// WITHOUT WARRANTY OF ANY KIND, either express or implied.
// See the License for the specific language governing rights and limitations
// under the License.
//
// The Original Code is: all this file.
//
// The Initial Developer of the Original Code is David A. Lee
//
// Portions created by (your name) are Copyright (C) (your legal entity). All
// Rights Reserved.
//
// Contributor(s): none.
//