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

  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 cmDependsC_h
#define cmDependsC_h

#include "cmDepends.h"
#include <cmsys/RegularExpression.hxx>
#include <queue>

/** \class cmDependsC
 * \brief Dependency scanner for C and C++ object files.
 */
class cmDependsC: public cmDepends
{
public:
  /** Checking instances need to know the build directory name and the
      relative path from the build directory to the target file.  */
  cmDependsC();
  cmDependsC(std::vector<std::string> const& includes,
             const char* scanRegex, const char* complainRegex,
             std::set<cmStdString> const& generatedFiles, const cmStdString& cachFileName);

  /** Virtual destructor to cleanup subclasses properly.  */
  virtual ~cmDependsC();
  
protected:
  typedef std::vector<char> t_CharBuffer;

  // Implement writing/checking methods required by superclass.
  virtual bool WriteDependencies(const char *src, 
                                 const char *file,
                                 std::ostream& makeDepends,
                                 std::ostream& internalDepends);

  // Method to scan a single file.
  void Scan(std::istream& is, const char* directory, const cmStdString& fullName);

  // Method to test for the existence of a file.
  bool FileExistsOrIsGenerated(const std::string& fname,
                               std::set<cmStdString>& scanned,
                               std::set<cmStdString>& dependencies);
  bool FileIsGenerated(const std::string& fname,
                       std::set<cmStdString>& scanned,
                       std::set<cmStdString>& dependencies);

  // The include file search path.
  std::vector<std::string> const* m_IncludePath;

  // Regular expression to identify C preprocessor include directives.
  cmsys::RegularExpression m_IncludeRegexLine;

  // Regular expressions to choose which include files to scan
  // recursively and which to complain about not finding.
  cmsys::RegularExpression m_IncludeRegexScan;
  cmsys::RegularExpression m_IncludeRegexComplain;

  // Set of generated files available.
  std::set<cmStdString> const* m_GeneratedFiles;
public:
  // Data structures for dependency graph walk.
  struct UnscannedEntry
  {
    cmStdString FileName;
    cmStdString QuotedLocation;
  };

  struct cmIncludeLines
  {
    cmIncludeLines(): m_Used(false) {}
    std::vector<UnscannedEntry> m_UnscannedEntries;
    bool m_Used;
  };
protected:
  std::set<cmStdString> m_Encountered;
  std::queue<UnscannedEntry> m_Unscanned;
  t_CharBuffer m_Buffer;

  std::map<cmStdString, cmIncludeLines *> m_fileCache;

  cmStdString m_cacheFileName;

  void WriteCacheFile() const;
  void ReadCacheFile();
private:
  cmDependsC(cmDependsC const&); // Purposely not implemented.
  void operator=(cmDependsC const&); // Purposely not implemented.
};

#endif