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#include "clangcodemodelserver.h"

#include "clangdocuments.h"
#include "clangfilesystemwatcher.h"
#include "clangtranslationunits.h"
#include "codecompleter.h"
#include "diagnosticset.h"
#include "highlightingmarks.h"
#include "clangexceptions.h"
#include "skippedsourceranges.h"

#include <clangbackendipcdebugutils.h>
#include <cmbcodecompletedmessage.h>
#include <cmbcompletecodemessage.h>
#include <cmbregisterprojectsforeditormessage.h>
#include <cmbregistertranslationunitsforeditormessage.h>
#include <cmbunregisterprojectsforeditormessage.h>
#include <cmbunregistertranslationunitsforeditormessage.h>
#include <documentannotationschangedmessage.h>
#include <registerunsavedfilesforeditormessage.h>
#include <requestdocumentannotations.h>
#include <projectpartsdonotexistmessage.h>
#include <translationunitdoesnotexistmessage.h>
#include <unregisterunsavedfilesforeditormessage.h>
#include <updatetranslationunitsforeditormessage.h>
#include <updatevisibletranslationunitsmessage.h>

#include <utils/qtcassert.h>

#include <QCoreApplication>
#include <QDebug>

static bool useSupportiveTranslationUnit()
{
    static bool use = !qEnvironmentVariableIntValue("QTC_CLANG_NO_SUPPORTIVE_TRANSLATIONUNIT");
    return use;
}

namespace ClangBackEnd {

ClangCodeModelServer::ClangCodeModelServer()
    : documents(projects, unsavedFiles)
{
    updateDocumentAnnotationsTimer.setSingleShot(true);
    QObject::connect(&updateDocumentAnnotationsTimer,
                     &QTimer::timeout,
                     [this]() {
        processJobsForDirtyAndVisibleDocuments();
    });

    updateVisibleButNotCurrentDocumentsTimer.setSingleShot(true);
    QObject::connect(&updateVisibleButNotCurrentDocumentsTimer,
                     &QTimer::timeout,
                     [this]() {
        processJobsForDirtyAndVisibleButNotCurrentDocuments();
    });

    QObject::connect(documents.clangFileSystemWatcher(),
                     &ClangFileSystemWatcher::fileChanged,
                     [this](const Utf8String &filePath) {
        ClangCodeModelServer::startDocumentAnnotationsTimerIfFileIsNotOpenAsDocument(filePath);
    });
}

void ClangCodeModelServer::end()
{
    QCoreApplication::exit();
}

void ClangCodeModelServer::registerTranslationUnitsForEditor(const ClangBackEnd::RegisterTranslationUnitForEditorMessage &message)
{
    TIME_SCOPE_DURATION("ClangCodeModelServer::registerTranslationUnitsForEditor");

    try {
        auto createdDocuments = documents.create(message.fileContainers());
        unsavedFiles.createOrUpdate(message.fileContainers());
        documents.setUsedByCurrentEditor(message.currentEditorFilePath());
        documents.setVisibleInEditors(message.visibleEditorFilePaths());

        processInitialJobsForDocuments(createdDocuments);
    } catch (const std::exception &exception) {
        qWarning() << "Error in ClangCodeModelServer::registerTranslationUnitsForEditor:" << exception.what();
    }
}

void ClangCodeModelServer::updateTranslationUnitsForEditor(const UpdateTranslationUnitsForEditorMessage &message)
{
    TIME_SCOPE_DURATION("ClangCodeModelServer::updateTranslationUnitsForEditor");

    try {
        const auto newerFileContainers = documents.newerFileContainers(message.fileContainers());
        if (newerFileContainers.size() > 0) {
            const std::vector<Document> updateDocuments = documents.update(newerFileContainers);
            unsavedFiles.createOrUpdate(newerFileContainers);

            // Start the jobs on the next event loop iteration since otherwise
            // we might block the translation unit for a completion request
            // that comes right after this message.
            updateDocumentAnnotationsTimer.start(0);
            delayStartInitializingSupportiveTranslationUnits(updateDocuments);
        }
    } catch (const std::exception &exception) {
        qWarning() << "Error in ClangCodeModelServer::updateTranslationUnitsForEditor:" << exception.what();
    }
}

void ClangCodeModelServer::unregisterTranslationUnitsForEditor(const ClangBackEnd::UnregisterTranslationUnitsForEditorMessage &message)
{
    TIME_SCOPE_DURATION("ClangCodeModelServer::unregisterTranslationUnitsForEditor");

    try {
        for (const auto &fileContainer : message.fileContainers()) {
            const Document &document = documents.document(fileContainer);
            documentProcessors().remove(document);
        }
        documents.remove(message.fileContainers());
        unsavedFiles.remove(message.fileContainers());
    } catch (const std::exception &exception) {
        qWarning() << "Error in ClangCodeModelServer::unregisterTranslationUnitsForEditor:" << exception.what();
    }
}

void ClangCodeModelServer::registerProjectPartsForEditor(const RegisterProjectPartsForEditorMessage &message)
{
    TIME_SCOPE_DURATION("ClangCodeModelServer::registerProjectPartsForEditor");

    try {
        projects.createOrUpdate(message.projectContainers());
        documents.setDocumentsDirtyIfProjectPartChanged();

        processJobsForDirtyAndVisibleDocuments();
    } catch (const std::exception &exception) {
        qWarning() << "Error in ClangCodeModelServer::registerProjectPartsForEditor:" << exception.what();
    }
}

void ClangCodeModelServer::unregisterProjectPartsForEditor(const UnregisterProjectPartsForEditorMessage &message)
{
    TIME_SCOPE_DURATION("ClangCodeModelServer::unregisterProjectPartsForEditor");

    try {
        projects.remove(message.projectPartIds());
    } catch (const std::exception &exception) {
        qWarning() << "Error in ClangCodeModelServer::unregisterProjectPartsForEditor:" << exception.what();
    }
}

void ClangCodeModelServer::registerUnsavedFilesForEditor(const RegisterUnsavedFilesForEditorMessage &message)
{
    TIME_SCOPE_DURATION("ClangCodeModelServer::registerUnsavedFilesForEditor");

    try {
        unsavedFiles.createOrUpdate(message.fileContainers());
        documents.updateDocumentsWithChangedDependencies(message.fileContainers());

        updateDocumentAnnotationsTimer.start(updateDocumentAnnotationsTimeOutInMs);
    } catch (const std::exception &exception) {
        qWarning() << "Error in ClangCodeModelServer::registerUnsavedFilesForEditor:" << exception.what();
    }
}

void ClangCodeModelServer::unregisterUnsavedFilesForEditor(const UnregisterUnsavedFilesForEditorMessage &message)
{
    TIME_SCOPE_DURATION("ClangCodeModelServer::unregisterUnsavedFilesForEditor");

    try {
        unsavedFiles.remove(message.fileContainers());
        documents.updateDocumentsWithChangedDependencies(message.fileContainers());
    } catch (const std::exception &exception) {
        qWarning() << "Error in ClangCodeModelServer::unregisterUnsavedFilesForEditor:" << exception.what();
    }
}

void ClangCodeModelServer::completeCode(const ClangBackEnd::CompleteCodeMessage &message)
{
    TIME_SCOPE_DURATION("ClangCodeModelServer::completeCode");

    try {
        auto document = documents.document(message.filePath(), message.projectPartId());

        JobRequest jobRequest = createJobRequest(document, JobRequest::Type::CompleteCode);
        jobRequest.line = message.line();
        jobRequest.column = message.column();
        jobRequest.ticketNumber = message.ticketNumber();

        DocumentProcessor processor = documentProcessors().processor(document);
        processor.addJob(jobRequest);
        processor.process();
    }  catch (const std::exception &exception) {
        qWarning() << "Error in ClangCodeModelServer::completeCode:" << exception.what();
    }
}

void ClangCodeModelServer::requestDocumentAnnotations(const RequestDocumentAnnotationsMessage &message)
{
    TIME_SCOPE_DURATION("ClangCodeModelServer::requestDocumentAnnotations");

    try {
        auto document = documents.document(message.fileContainer().filePath(),
                                           message.fileContainer().projectPartId());

        const JobRequest jobRequest = createJobRequest(document,
                                                       JobRequest::Type::RequestDocumentAnnotations);

        DocumentProcessor processor = documentProcessors().processor(document);
        processor.addJob(jobRequest);
        processor.process();
    }  catch (const std::exception &exception) {
        qWarning() << "Error in ClangCodeModelServer::requestDocumentAnnotations:" << exception.what();
    }
}

void ClangCodeModelServer::updateVisibleTranslationUnits(const UpdateVisibleTranslationUnitsMessage &message)
{
    TIME_SCOPE_DURATION("ClangCodeModelServer::updateVisibleTranslationUnits");

    try {
        documents.setUsedByCurrentEditor(message.currentEditorFilePath());
        documents.setVisibleInEditors(message.visibleEditorFilePaths());
        updateDocumentAnnotationsTimer.start(0);
    }  catch (const std::exception &exception) {
        qWarning() << "Error in ClangCodeModelServer::updateVisibleTranslationUnits:" << exception.what();
    }
}

const Documents &ClangCodeModelServer::documentsForTestOnly() const
{
    return documents;
}

void ClangCodeModelServer::startDocumentAnnotationsTimerIfFileIsNotOpenAsDocument(const Utf8String &filePath)
{
    if (!documents.hasDocumentWithFilePath(filePath))
        updateDocumentAnnotationsTimer.start(0);
}

QList<Jobs::RunningJob> ClangCodeModelServer::runningJobsForTestsOnly()
{
    return documentProcessors().runningJobs();
}

int ClangCodeModelServer::queueSizeForTestsOnly()
{
    return documentProcessors().queueSize();
}

bool ClangCodeModelServer::isTimerRunningForTestOnly() const
{
    return updateDocumentAnnotationsTimer.isActive();
}

void ClangCodeModelServer::processJobsForDirtyAndVisibleDocuments()
{
    processJobsForDirtyCurrentDocument();
    processTimerForVisibleButNotCurrentDocuments();
}

void ClangCodeModelServer::processJobsForDirtyCurrentDocument()
{
    const auto currentDirtyDocuments = documents.filtered([](const Document &document) {
        return document.isDirty() && document.isUsedByCurrentEditor();
    });
    QTC_CHECK(currentDirtyDocuments.size() <= 1);

    addAndRunUpdateJobs(currentDirtyDocuments);
}

void ClangCodeModelServer::addAndRunUpdateJobs(const std::vector<Document> &documents)
{
    for (const auto &document : documents) {
        DocumentProcessor processor = documentProcessors().processor(document);
        processor.addJob(createJobRequest(document,
                                          JobRequest::Type::UpdateDocumentAnnotations,
                                          PreferredTranslationUnit::PreviouslyParsed));
        processor.process();
    }
}

void ClangCodeModelServer::processTimerForVisibleButNotCurrentDocuments()
{
    if (documents.dirtyAndVisibleButNotCurrentDocuments().empty()) {
        updateVisibleButNotCurrentDocumentsTimer.stop();
    } else {
        updateVisibleButNotCurrentDocumentsTimer.start(
                    updateVisibleButNotCurrentDocumentsTimeOutInMs);
    }
}

void ClangCodeModelServer::processJobsForDirtyAndVisibleButNotCurrentDocuments()
{
    addAndRunUpdateJobs(documents.dirtyAndVisibleButNotCurrentDocuments());
}

void ClangCodeModelServer::processInitialJobsForDocuments(const std::vector<Document> &documents)
{
    for (const auto &document : documents) {
        DocumentProcessor processor = documentProcessors().create(document);
        const auto jobRequestCreator = [this](const Document &document,
                JobRequest::Type jobRequestType,
                PreferredTranslationUnit preferredTranslationUnit) {
            return createJobRequest(document, jobRequestType, preferredTranslationUnit);
        };
        processor.setJobRequestCreator(jobRequestCreator);

        processor.addJob(createJobRequest(document, JobRequest::Type::UpdateDocumentAnnotations));
        processor.addJob(createJobRequest(document, JobRequest::Type::CreateInitialDocumentPreamble));
        processor.process();
    }
}

void ClangCodeModelServer::delayStartInitializingSupportiveTranslationUnits(
        const std::vector<Document> &documents)
{
    if (useSupportiveTranslationUnit()) {
        QTimer::singleShot(0, [this, documents](){
            startInitializingSupportiveTranslationUnits(documents);
        });
    }
}

void ClangCodeModelServer::startInitializingSupportiveTranslationUnits(
        const std::vector<Document> &documents)
{
    for (const Document &document : documents) {
        try {
            DocumentProcessor processor = documentProcessors().processor(document);
            if (!processor.hasSupportiveTranslationUnit())
                processor.startInitializingSupportiveTranslationUnit();
        } catch (const DocumentProcessorDoesNotExist &) {
            // OK, document was already closed.
        }
    }
}

JobRequest ClangCodeModelServer::createJobRequest(
        const Document &document,
        JobRequest::Type type,
        PreferredTranslationUnit preferredTranslationUnit) const
{
    JobRequest jobRequest;
    jobRequest.type = type;
    jobRequest.requirements = JobRequest::requirementsForType(type);
    jobRequest.filePath = document.filePath();
    jobRequest.projectPartId = document.projectPartId();
    jobRequest.unsavedFilesChangeTimePoint = unsavedFiles.lastChangeTimePoint();
    jobRequest.documentRevision = document.documentRevision();
    jobRequest.preferredTranslationUnit = preferredTranslationUnit;
    const ProjectPart &projectPart = projects.project(document.projectPartId());
    jobRequest.projectChangeTimePoint = projectPart.lastChangeTimePoint();

    return jobRequest;
}

void ClangCodeModelServer::setUpdateDocumentAnnotationsTimeOutInMsForTestsOnly(int value)
{
    updateDocumentAnnotationsTimeOutInMs = value;
}

void ClangCodeModelServer::setUpdateVisibleButNotCurrentDocumentsTimeOutInMsForTestsOnly(int value)
{
    updateVisibleButNotCurrentDocumentsTimeOutInMs = value;
}

DocumentProcessors &ClangCodeModelServer::documentProcessors()
{
    if (!documentProcessors_) {
        // DocumentProcessors needs a reference to the client, but the client
        // is not known at construction time of ClangCodeModelServer, so
        // construct DocumentProcessors in a lazy manner.
        documentProcessors_.reset(new DocumentProcessors(documents, unsavedFiles, projects, *client()));
    }

    return *documentProcessors_.data();
}

} // namespace ClangBackEnd