/*
 * 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 Software Foundation, Inc.
 *   59 Temple Place, Suite 330
 *   Boston, MA 02111-1307  USA
 *
 * @author Scott Ferguson
 */

package com.caucho.quercus.env;

/**
 * Encapsulates an environment entry for a variable.  The EnvVar is a
 * container for Vars.
 */
public class LazySaveEnvVar extends EnvVar
{
  private int _id;
  private Value _value;

  public LazySaveEnvVar(int id, Value value)
  {
    _id = id;
    _value = value;
  }
  
  /**
   * Returns the current value.
   */
  public Value get()
  {
    return getEnvVar().get();
  }

  /**
   * Sets the current value.
   */
  public Value set(Value value)
  {
    return getEnvVar().set(value);
  }

  /**
   * Returns the current Var.
   */
  public Var getVar()
  {
    return getEnvVar().getVar();
  }

  /**
   * Sets the var.
   */
  public Var setVar(Var var)
  {
    return getEnvVar().setVar(var);
  }

  private EnvVar getEnvVar()
  {
    Env env = Env.getCurrent();
    EnvVar []globals = env.getGlobalList();

    if (globals[_id] == this) {
      EnvVar var = new EnvVarImpl(new Var());

      var.set(_value.copy(env));

      globals[_id] = var;
    }

    return globals[_id];
  }
}