// Copyright (C) 2011, 2012  Strahinja Val Markovic  <val@markovic.io>
//
// This file is part of YouCompleteMe.
//
// YouCompleteMe 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 3 of the License, or
// (at your option) any later version.
//
// YouCompleteMe 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.  See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with YouCompleteMe.  If not, see <http://www.gnu.org/licenses/>.

#ifndef CLANGCOMPLETE_H_WLKDU0ZV
#define CLANGCOMPLETE_H_WLKDU0ZV

#include "ConcurrentLatestValue.h"
#include "Future.h"
#include "UnsavedFile.h"

#include <boost/utility.hpp>
#include <boost/unordered_map.hpp>

#include <string>

typedef void *CXIndex;
typedef struct CXTranslationUnitImpl *CXTranslationUnit;

namespace YouCompleteMe
{

class CandidateRepository;
struct CompletionData;

typedef boost::shared_ptr< std::vector< CompletionData > > AsyncCompletions;

typedef boost::unordered_map< std::string, std::vector< std::string > >
  FlagsForFile;

typedef boost::unordered_map< std::string, CXTranslationUnit >
  TranslationUnitForFilename;


class ClangCompleter : boost::noncopyable
{
public:
  ClangCompleter();
  ~ClangCompleter();

  void EnableThreading();

  void SetGlobalCompileFlags( const std::vector< std::string > &flags );

  void SetFileCompileFlags( const std::string &filename,
                            const std::vector< std::string > &flags );

  void UpdateTranslationUnit( const std::string &filename,
                              const std::vector< UnsavedFile > &unsaved_files );

  std::vector< CompletionData > CandidatesForLocationInFile(
      const std::string &filename,
      int line,
      int column,
      const std::vector< UnsavedFile > &unsaved_files );

  Future< AsyncCompletions > CandidatesForQueryAndLocationInFileAsync(
      const std::string &query,
      const std::string &filename,
      int line,
      int column,
      const std::vector< UnsavedFile > &unsaved_files );

private:
  typedef ConcurrentLatestValue<
            boost::shared_ptr<
              boost::packaged_task< AsyncCompletions > > > LatestTask;

  // caller takes ownership of translation unit
  CXTranslationUnit CreateTranslationUnit(
      const std::string &filename,
      const std::vector< UnsavedFile > &unsaved_files );

  std::vector< const char* > ClangFlagsForFilename(
      const std::string &filename );

  CXTranslationUnit GetTranslationUnitForFile(
      const std::string &filename,
      const std::vector< UnsavedFile > &unsaved_files );

  std::vector< CompletionData > SortCandidatesForQuery(
      const std::string &query,
      const std::vector< CompletionData > &completion_datas );

  void InitThreads();

  void ClangThreadMain( LatestTask &clang_task );

  void SortingThreadMain( LatestTask &sorting_task );


  /////////////////////////////
  // PRIVATE MEMBER VARIABLES
  /////////////////////////////

  CXIndex clang_index_;

  FlagsForFile flags_for_file_;

  TranslationUnitForFilename filename_to_translation_unit_;

  std::vector< std::string > global_flags_;

  CandidateRepository &candidate_repository_;

  mutable LatestTask clang_task_;

  mutable LatestTask sorting_task_;

  bool threading_enabled_;

  // TODO: use boost.atomic for clang_data_ready_
  bool clang_data_ready_;
  boost::mutex clang_data_ready_mutex_;
  boost::condition_variable clang_data_ready_condition_variable_;

  std::vector< CompletionData > latest_clang_results_;
  boost::shared_mutex latest_clang_results_shared_mutex_;

  // Unfortunately clang is not thread-safe so we can only ever use one thread
  // to access it. So this one background thread will be the only thread that
  // can access libclang.
  boost::thread clang_thread_;

  boost::thread_group sorting_threads_;
};

} // namespace YouCompleteMe

#endif /* end of include guard: CLANGCOMPLETE_H_WLKDU0ZV */