/*=========================================================================

  Program:   CMake - Cross-Platform Makefile Generator
  Module:    $RCSfile$
  Language:  C++
  Date:      $Date$
  Version:   $Revision$

  Copyright (c) 2002 Kitware, Inc., Insight Consortium.  All rights reserved.
  See Copyright.txt or http://www.cmake.org/HTML/Copyright.html for details.

     This software is distributed WITHOUT ANY WARRANTY; without even 
     the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR 
     PURPOSE.  See the above copyright notices for more information.

=========================================================================*/
#ifndef cmLoadCacheCommand_h
#define cmLoadCacheCommand_h

#include "cmCommand.h"

/** \class cmLoadCacheCommand
 * \brief load a cache file
 *
 * cmLoadCacheCommand loads the non internal values of a cache file
 */
class cmLoadCacheCommand : public cmCommand
{
public:
  /**
   * This is a virtual constructor for the command.
   */
  virtual cmCommand* Clone() 
    {
    return new cmLoadCacheCommand;
    }

  /**
   * This is called when the command is first encountered in
   * the CMakeLists.txt file.
   */
  virtual bool InitialPass(std::vector<std::string> const& args,
                           cmExecutionStatus &status);

  /**
   * The name of the command as specified in CMakeList.txt.
   */
  virtual const char* GetName() { return "load_cache";}

  /**
   * Succinct documentation.
   */
  virtual const char* GetTerseDocumentation() 
    {
    return "Load in the values from another project's CMake cache.";
    }
  
  /**
   * More documentation.
   */
  virtual const char* GetFullDocumentation()
    {
    return
      "  load_cache(pathToCacheFile READ_WITH_PREFIX\n"
      "             prefix entry1...)\n"
      "Read the cache and store the requested entries in variables with "
      "their name prefixed with the given prefix.  "
      "This only reads the values, and does not create entries in the local "
      "project's cache.\n"
      "  load_cache(pathToCacheFile [EXCLUDE entry1...]\n"
      "             [INCLUDE_INTERNALS entry1...])\n"
      "Load in the values from another cache and store them in the local "
      "project's cache as internal entries.  This is useful for a project "
      "that depends on another project built in a different tree.  "
      "EXCLUDE option can be used to provide a list of entries to be "
      "excluded.  "
      "INCLUDE_INTERNALS can be used to provide a list of internal entries "
      "to be included.  Normally, no internal entries are brought in.  Use "
      "of this form of the command is strongly discouraged, but it is "
      "provided for backward compatibility.";
    }
  
  cmTypeMacro(cmLoadCacheCommand, cmCommand);
protected:
  
  std::set<cmStdString> VariablesToRead;
  std::string Prefix;
  
  bool ReadWithPrefix(std::vector<std::string> const& args);
  void CheckLine(const char* line);
  bool ParseEntry(const char* entry, std::string& var, std::string& value);
};


#endif