#include <iostream>
#include "clang/Lex/Token.h"
#include "clang/Basic/IdentifierTable.h"
#include "FindTrickICG.hh"
#include "Utilities.hh"

FindTrickICG::FindTrickICG(clang::CompilerInstance & in_ci, HeaderSearchDirs & in_hsd , bool in_print_msgs )
 : ci(in_ci) , hsd(in_hsd) , print_msgs(in_print_msgs) , header_printed(false) { }

void FindTrickICG::FileChanged(clang::SourceLocation Loc, FileChangeReason Reason,
                         clang::SrcMgr::CharacteristicKind FileType,
                         clang::FileID PrevFID ) {
    /*
       We are interested when the file changes, specifically when we enter and exit a file.
       We are maintaining a stack of file names.  When a file is entered the name is
       pushed to the stack.  When a file is exited, we pop a name from the stack.
    */
    if ( Loc.isValid() and Loc.isFileID() ) {
        clang::PresumedLoc PLoc = ci.getSourceManager().getPresumedLoc(Loc) ;
        std::string loc_str ;
        if ( ! PLoc.isInvalid()) {
            loc_str = PLoc.getFilename() ;
            switch (Reason) {
                case EnterFile :
                    included_files.push_back(loc_str) ;
                    break ;
                case ExitFile :
                    included_files.pop_back() ;
                    break ;
                default:
                    break ;
            }
        }
    }
}

#if (LIBCLANG_MAJOR < 10) // TODO delete when RHEL 7 no longer supported
void FindTrickICG::FileSkipped(const clang::FileEntry &SkippedFile,
                           const clang::Token &FilenameTok,
                           clang::SrcMgr::CharacteristicKind FileType) {
    std::string file_name = SkippedFile.getName() ;
#else
void FindTrickICG::FileSkipped(const clang::FileEntryRef & SkippedFile, const clang::Token & FilenameTok,
                        clang::SrcMgr::CharacteristicKind FileType) {
    /* Files that have header guards are only preprocessed once because of an optimization.
    We still need to add its include chain to compat15 if TRICK_ICG was found when it was
    originally preprocessed */
    std::string file_name = SkippedFile.getName().str() ;
#endif
    std::string file_path;
    {
        char* path_cstr = almostRealPath(file_name.c_str());
        if(path_cstr != NULL) {
            file_path = std::string(path_cstr);
            free(path_cstr);
        }
    }

    // Check if skipped header is in Compat15
    if(hsd.isPathInCompat15(file_path)) {
        // for each header in the stack, mark them as being exposed to TRICK_ICG
        for (std::string& file : included_files) {
            hsd.addTrickICGFoundFile(file);
        }
    }
}


#if (LIBCLANG_MAJOR > 3) || ((LIBCLANG_MAJOR == 3) && (LIBCLANG_MINOR >= 5))
void FindTrickICG::If(clang::SourceLocation Loc, clang::SourceRange ConditionRange, clang::PPCallbacks::ConditionValueKind ConditionValue)
#else
void FindTrickICG::If(clang::SourceLocation Loc, clang::SourceRange ConditionRange, bool ConditionValue)
#endif
{
    if ( ConditionRange.isValid() ) {
        // Get the full text of the if statement into a string
        llvm::StringRef ref = clang::Lexer::getSourceText(clang::CharSourceRange::getCharRange(ConditionRange), ci.getSourceManager(), clang::LangOptions());
        // if the if statement contains TRICK_ICG we need to mark it.
        if ( ref.str().find("TRICK_ICG") != std::string::npos ) {
            // for each header in the stack, mark them as being exposed to TRICK_ICG
            std::vector<std::string>::iterator it ;
            for ( it = included_files.begin() ; it != included_files.end() ; ++it ) {
                hsd.addTrickICGFoundFile(*it) ;
            }
            // print warning messages.
            if ( print_msgs ) {
                print_header() ;
                std::string loc_str = Loc.printToString(ci.getSourceManager()) ;
                char * rpath = almostRealPath(loc_str.c_str()) ;
                if ( rpath ) {
                     std::cout << color(WARNING,
                      std::string("Warning: TRICK_ICG used in preprocessor conditional ") + rpath) << std::endl ;
                } else {
                     std::cout << color(WARNING,
                      std::string("Warning: TRICK_ICG used in preprocessor conditional ") + loc_str) << std::endl ;
                }
            }
        }
    }
}

#if (LIBCLANG_MAJOR > 3) || ((LIBCLANG_MAJOR == 3) && (LIBCLANG_MINOR >= 5))
void FindTrickICG::ElIf(clang::SourceLocation Loc, clang::SourceRange ConditionRange, clang::PPCallbacks::ConditionValueKind ConditionValue)
#else
void FindTrickICG::ElIf(clang::SourceLocation Loc, clang::SourceRange ConditionRange, bool ConditionValue)
#endif
{
    // Do the same processing for an #elif statement as an #if statement.
    If(Loc,ConditionRange,ConditionValue) ;
}

#if (LIBCLANG_MAJOR > 3) || ((LIBCLANG_MAJOR == 3) && (LIBCLANG_MINOR >= 7))
void FindTrickICG::Ifdef(clang::SourceLocation Loc, const clang::Token &MacroNameTok, const clang::MacroDefinition &MD)
#else
void FindTrickICG::Ifdef(clang::SourceLocation Loc, const clang::Token &MacroNameTok, const clang::MacroDirective *MD)
#endif
{
    // Get the token name that is being tested.
    std::string name = MacroNameTok.getIdentifierInfo()->getName().str() ;
    if ( ! name.compare("TRICK_ICG") ) {
        std::string loc_str = Loc.printToString(ci.getSourceManager()) ;
        // There is a singular ifdef TRICK_ICG in S_source.hh we need to ignore.
        if ( (loc_str.find("S_source.hh") == std::string::npos) ) {
            // for each header in the stack, mark them as being exposed to TRICK_ICG
            std::vector<std::string>::iterator it ;
            for ( it = included_files.begin() ; it != included_files.end() ; ++it ) {
                hsd.addTrickICGFoundFile(*it) ;
            }
            // print warning messages.
            if ( print_msgs ) {
                print_header() ;
                std::cout << color(WARNING,std::string("Warning: ifdef TRICK_ICG found ") + loc_str) << std::endl ;
            }
        }
    }

}

#if (LIBCLANG_MAJOR > 3) || ((LIBCLANG_MAJOR == 3) && (LIBCLANG_MINOR >= 7))
void FindTrickICG::Ifndef(clang::SourceLocation Loc, const clang::Token &MacroNameTok, const clang::MacroDefinition &MD)
#else
void FindTrickICG::Ifndef(clang::SourceLocation Loc, const clang::Token &MacroNameTok, const clang::MacroDirective *MD)
#endif
{
    // Get the token name that is being tested.
    std::string name = MacroNameTok.getIdentifierInfo()->getName().str() ;
    if ( ! name.compare("TRICK_ICG") ) {
        std::string loc_str = Loc.printToString(ci.getSourceManager()) ;
        // for each header in the stack, mark them as being exposed to TRICK_ICG
        std::vector<std::string>::iterator it ;
        for ( it = included_files.begin() ; it != included_files.end() ; ++it ) {
            hsd.addTrickICGFoundFile(*it) ;
        }
        // print warning messages.
        if ( print_msgs ) {
            print_header() ;
            std::cout << color(WARNING, std::string("Warning: ifndef TRICK_ICG found ") + loc_str) << std::endl ;
        }
    }
}

void FindTrickICG::print_header() {
    // Print the warning message once.
    if ( ! header_printed ) {
        std::cout << color(WARNING, std::string(
         "Warning: TRICK_ICG found in one or more header files.  The use of TRICK_ICG precludes the use of\n"
         "some C++ class/structures in these headers.  Consider removing the TRICK_ICG preprocessor conditionals\n")) ;
        header_printed = true ;
    }
}