#include <vector>
#include <string>
#include "clang/Frontend/CompilerInstance.h"
#include "clang/Lex/PPCallbacks.h"
#include "HeaderSearchDirs.hh"

/*
   FindTrickICG searches preprocessor directives #if/#elif/#ifdef/#ifndef to see if they use TRICK_ICG
   If they do reference TRICK_ICG we need to mark the stack of incude files that include the TRICK_ICG.
   We also print a warning to the screen where the TRICK_ICG was found.
 */

class FindTrickICG : public clang::PPCallbacks {
  public:
    FindTrickICG(clang::CompilerInstance & in_ci , HeaderSearchDirs & in_hsd , bool in_print_msgs ) ;

    // called when the file changes for a variety of reasons.
    virtual void FileChanged(clang::SourceLocation Loc, FileChangeReason Reason,
                           clang::SrcMgr::CharacteristicKind FileType,
                           clang::FileID PrevFID = clang::FileID()) ;

#if (LIBCLANG_MAJOR < 10) // TODO delete when RHEL 7 no longer supported
  virtual void FileSkipped(const clang::FileEntry &SkippedFile,
                           const clang::Token &FilenameTok,
                           clang::SrcMgr::CharacteristicKind FileType) ;
#else
    // called when a header file is skipped because of a header guard optimization.
    virtual void FileSkipped(const clang::FileEntryRef & SkippedFile,
                        const clang::Token & FilenameTok,
                        clang::SrcMgr::CharacteristicKind FileType) ;
#endif

    // callbacks called when the preprocessor directives of types are processed.
#if (LIBCLANG_MAJOR > 3) || ((LIBCLANG_MAJOR == 3) && (LIBCLANG_MINOR >= 5))
    virtual void If(clang::SourceLocation Loc, clang::SourceRange ConditionRange, clang::PPCallbacks::ConditionValueKind ConditionValue) ;
    virtual void ElIf(clang::SourceLocation Loc, clang::SourceRange ConditionRange, clang::PPCallbacks::ConditionValueKind ConditionValue) ;
#else
    virtual void If(clang::SourceLocation Loc, clang::SourceRange ConditionRange, bool ConditionValue) ;
    virtual void ElIf(clang::SourceLocation Loc, clang::SourceRange ConditionRange, bool ConditionValue) ;
#endif
#if (LIBCLANG_MAJOR > 3) || ((LIBCLANG_MAJOR == 3) && (LIBCLANG_MINOR >= 7))
    virtual void Ifdef(clang::SourceLocation Loc, const clang::Token &MacroNameTok, const clang::MacroDefinition &MD) ;
    virtual void Ifndef(clang::SourceLocation Loc, const clang::Token &MacroNameTok, const clang::MacroDefinition &MD) ;
#else
    virtual void Ifdef(clang::SourceLocation Loc, const clang::Token &MacroNameTok, const clang::MacroDirective *MD) ;
    virtual void Ifndef(clang::SourceLocation Loc, const clang::Token &MacroNameTok, const clang::MacroDirective *MD) ;
#endif

    // print a warning about using TRICK_ICG.
    void print_header() ;

  private:

    // compiler instance to help locating file names
    clang::CompilerInstance & ci ;

    HeaderSearchDirs & hsd ;

    // Are we printing warning messages?
    bool print_msgs ;

    // Have we printed the big warning about TRICK_ICG?
    bool header_printed ;

    // Using a vector as a stack to hold the stack of included headers we have entered.
    std::vector<std::string> included_files ;
} ;