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** Copyright (C) 2018 The Qt Company Ltd.
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** General Public License version 3 as published by the Free Software
** Foundation with exceptions as appearing in the file LICENSE.GPL3-EXCEPT
** included in the packaging of this file. Please review the following
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#pragma once

#include "sourcelocationsutils.h"
#include "sourcesmanager.h"
#include "symbolentry.h"

#include <filepathcachinginterface.h>

#include <utils/linecolumn.h>
#include <utils/optional.h>

#include <clang/Basic/SourceLocation.h>
#include <clang/Basic/SourceManager.h>
#include <clang/Index/USRGeneration.h>
#include <llvm/ADT/SmallVector.h>

namespace ClangBackEnd {

class SymbolsVisitorBase
{
public:
    SymbolsVisitorBase(const FilePathCachingInterface &filePathCache,
                       const clang::SourceManager *sourceManager,
                       SourcesManager &sourcesManager)
        : m_filePathCache(filePathCache),
          m_sourceManager(sourceManager),
          m_sourcesManager(sourcesManager)
    {}

    FilePathId filePathId(clang::SourceLocation sourceLocation)
    {
        clang::FileID clangFileId = m_sourceManager->getFileID(sourceLocation);
        const clang::FileEntry *fileEntry = m_sourceManager->getFileEntryForID(clangFileId);

        return filePathId(fileEntry);
    }

    bool dependentFilesAreModified()
    {
        return m_sourcesManager.dependentFilesModified();
    }

    bool isAlreadyParsed(clang::FileID fileId)
    {
        const clang::FileEntry *fileEntry = m_sourceManager->getFileEntryForID(fileId);
        if (!fileEntry)
            return false;
        return m_sourcesManager.alreadyParsed(filePathId(fileEntry),
                                              fileEntry->getModificationTime());
    }

    bool alreadyParsed(clang::SourceLocation sourceLocation)
    {
        return isAlreadyParsed(m_sourceManager->getFileID(sourceLocation));
    }

    FilePathId filePathId(const clang::FileEntry *fileEntry)
    {
        if (fileEntry) {
            uint fileId = fileEntry->getUID();

            if (fileId >= m_filePathIndices.size())
                m_filePathIndices.resize(fileId + 1);

            FilePathId &filePathId = m_filePathIndices[fileId];

            if (filePathId.isValid())
                return filePathId;

            auto filePath = fileEntry->getName();
            FilePathId newFilePathId = m_filePathCache.filePathId(FilePath::fromNativeFilePath(absolutePath(filePath)));

            filePathId = newFilePathId;

            return newFilePathId;
        }

        return {};
    }

    Utils::LineColumn lineColum(clang::SourceLocation sourceLocation)
    {
        return {int(m_sourceManager->getSpellingLineNumber(sourceLocation)),
                int(m_sourceManager->getSpellingColumnNumber(sourceLocation))};
    }

    static Utils::optional<Utils::PathString> generateUSR(const clang::Decl *declaration)
    {
        llvm::SmallVector<char, 128> usr;

        Utils::optional<Utils::PathString> usrOptional;

        bool wasNotWorking = clang::index::generateUSRForDecl(declaration, usr);

        if (!wasNotWorking)
            usrOptional.emplace(usr.data(), usr.size());

        return usrOptional;
    }

    Utils::optional<Utils::PathString> generateUSR(clang::StringRef macroName,
                                                   clang::SourceLocation sourceLocation)
    {
        llvm::SmallVector<char, 128> usr;

        Utils::optional<Utils::PathString> usrOptional;

        bool wasNotWorking = clang::index::generateUSRForMacro(macroName,
                                                               sourceLocation,
                                                               *m_sourceManager,
                                                               usr);

        if (!wasNotWorking)
            usrOptional.emplace(usr.data(), usr.size());

        return usrOptional;
    }

    static SymbolIndex toSymbolIndex(const void *pointer)
    {
        return SymbolIndex(reinterpret_cast<std::uintptr_t>(pointer));
    }

    void setSourceManager(clang::SourceManager *sourceManager)
    {
        m_sourceManager = sourceManager;
    }

    bool isInSystemHeader(clang::FileID fileId) const
    {
        return isSystem(m_sourceManager->getSLocEntry(fileId).getFile().getFileCharacteristic());
    }

    static
    bool isSystem(clang::SrcMgr::CharacteristicKind kind)
    {
        return clang::SrcMgr::isSystem(kind);
    }

    void clear()
    {
        m_filePathIndices.clear();
    }

protected:
    std::vector<FilePathId> m_filePathIndices;
    const FilePathCachingInterface &m_filePathCache;
    const clang::SourceManager *m_sourceManager = nullptr;
    SourcesManager &m_sourcesManager;
};

} // namespace ClangBackend