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#include "clangmodelmanagersupport.h"

#include "constants.h"
#include "clangeditordocumentprocessor.h"
#include "clangutils.h"

#include <coreplugin/editormanager/editormanager.h>
#include <cpptools/baseeditordocumentparser.h>
#include <cpptools/editordocumenthandle.h>
#include <projectexplorer/project.h>

#include <clangbackendipc/cmbregisterprojectsforeditormessage.h>
#include <clangbackendipc/filecontainer.h>
#include <clangbackendipc/projectpartcontainer.h>
#include <utils/qtcassert.h>

#include <QCoreApplication>
#include <QMenu>
#include <QTextBlock>

using namespace ClangCodeModel;
using namespace ClangCodeModel::Internal;

static ModelManagerSupportClang *m_instance_forTestsOnly = 0;

static CppTools::CppModelManager *cppModelManager()
{
    return CppTools::CppModelManager::instance();
}

ModelManagerSupportClang::ModelManagerSupportClang()
    : m_completionAssistProvider(m_ipcCommunicator)
{
    QTC_CHECK(!m_instance_forTestsOnly);
    m_instance_forTestsOnly = this;

    Core::EditorManager *editorManager = Core::EditorManager::instance();
    connect(editorManager, &Core::EditorManager::currentEditorChanged,
            this, &ModelManagerSupportClang::onCurrentEditorChanged);
    connect(editorManager, &Core::EditorManager::editorOpened,
            this, &ModelManagerSupportClang::onEditorOpened);

    CppTools::CppModelManager *modelManager = cppModelManager();
    connect(modelManager, &CppTools::CppModelManager::abstractEditorSupportContentsUpdated,
            this, &ModelManagerSupportClang::onAbstractEditorSupportContentsUpdated);
    connect(modelManager, &CppTools::CppModelManager::abstractEditorSupportRemoved,
            this, &ModelManagerSupportClang::onAbstractEditorSupportRemoved);
    connect(modelManager, &CppTools::CppModelManager::projectPartsUpdated,
            this, &ModelManagerSupportClang::onProjectPartsUpdated);
    connect(modelManager, &CppTools::CppModelManager::projectPartsRemoved,
            this, &ModelManagerSupportClang::onProjectPartsRemoved);
}

ModelManagerSupportClang::~ModelManagerSupportClang()
{
    m_instance_forTestsOnly = 0;
}

CppTools::CppCompletionAssistProvider *ModelManagerSupportClang::completionAssistProvider()
{
    return &m_completionAssistProvider;
}

CppTools::BaseEditorDocumentProcessor *ModelManagerSupportClang::editorDocumentProcessor(
        TextEditor::TextDocument *baseTextDocument)
{
    return new ClangEditorDocumentProcessor(this, baseTextDocument);
}

void ModelManagerSupportClang::onCurrentEditorChanged(Core::IEditor *newCurrent)
{
    // If we switch away from a cpp editor, update the backend about
    // the document's unsaved content.
    if (m_previousCppEditor && m_previousCppEditor->document()->isModified()) {
        m_ipcCommunicator.updateTranslationUnitFromCppEditorDocument(
                                m_previousCppEditor->document()->filePath().toString());
    }

    // Remember previous editor
    if (newCurrent && cppModelManager()->isCppEditor(newCurrent))
        m_previousCppEditor = newCurrent;
    else
        m_previousCppEditor.clear();
}

void ModelManagerSupportClang::connectTextDocumentToTranslationUnit(TextEditor::TextDocument *textDocument)
{
    // Handle externally changed documents
    connect(textDocument, &Core::IDocument::reloadFinished,
            this, &ModelManagerSupportClang::onCppDocumentReloadFinishedOnTranslationUnit,
            Qt::UniqueConnection);

    // Handle changes from e.g. refactoring actions
    connect(textDocument, &TextEditor::TextDocument::contentsChangedWithPosition,
            this, &ModelManagerSupportClang::onCppDocumentContentsChangedOnTranslationUnit,
            Qt::UniqueConnection);
}

void ModelManagerSupportClang::connectTextDocumentToUnsavedFiles(TextEditor::TextDocument *textDocument)
{
    // Handle externally changed documents
    connect(textDocument, &Core::IDocument::reloadFinished,
            this, &ModelManagerSupportClang::onCppDocumentReloadFinishedOnUnsavedFile,
            Qt::UniqueConnection);

    // Handle changes from e.g. refactoring actions
    connect(textDocument, &TextEditor::TextDocument::contentsChanged,
            this, &ModelManagerSupportClang::onCppDocumentContentsChangedOnUnsavedFile,
            Qt::UniqueConnection);
}

void ModelManagerSupportClang::connectToWidgetsMarkContextMenuRequested(QWidget *editorWidget)
{
    const auto widget = qobject_cast<TextEditor::TextEditorWidget *>(editorWidget);
    if (widget) {
        connect(widget, &TextEditor::TextEditorWidget::markContextMenuRequested,
                this, &ModelManagerSupportClang::onTextMarkContextMenuRequested);
    }
}

void ModelManagerSupportClang::onEditorOpened(Core::IEditor *editor)
{
    QTC_ASSERT(editor, return);
    Core::IDocument *document = editor->document();
    QTC_ASSERT(document, return);
    TextEditor::TextDocument *textDocument = qobject_cast<TextEditor::TextDocument *>(document);

    if (textDocument && cppModelManager()->isCppEditor(editor)) {
        const QString clangSupportId = QLatin1String(Constants::CLANG_MODELMANAGERSUPPORT_ID);
        if (cppModelManager()->isManagedByModelManagerSupport(textDocument, clangSupportId)) {
            connectTextDocumentToTranslationUnit(textDocument);
            connectToWidgetsMarkContextMenuRequested(editor->widget());
        } else {
            connectTextDocumentToUnsavedFiles(textDocument);
        }

        // TODO: Ensure that not fully loaded documents are updated?
    }
}

void ModelManagerSupportClang::onCppDocumentReloadFinishedOnTranslationUnit(bool success)
{
    if (success) {
        Core::IDocument *document = qobject_cast<Core::IDocument *>(sender());
        m_ipcCommunicator.updateTranslationUnitIfNotCurrentDocument(document);
    }
}

void ModelManagerSupportClang::onCppDocumentContentsChangedOnTranslationUnit(int position,
                                                                             int /*charsRemoved*/,
                                                                             int /*charsAdded*/)
{
    Core::IDocument *document = qobject_cast<Core::IDocument *>(sender());

    m_ipcCommunicator.updateChangeContentStartPosition(document->filePath().toString(),
                                                       position);
    m_ipcCommunicator.updateTranslationUnitIfNotCurrentDocument(document);
}

void ModelManagerSupportClang::onCppDocumentReloadFinishedOnUnsavedFile(bool success)
{
    if (success) {
        Core::IDocument *document = qobject_cast<Core::IDocument *>(sender());
        m_ipcCommunicator.updateUnsavedFile(document);
    }
}

void ModelManagerSupportClang::onCppDocumentContentsChangedOnUnsavedFile()
{
    Core::IDocument *document = qobject_cast<Core::IDocument *>(sender());
    m_ipcCommunicator.updateUnsavedFile(document);
}

void ModelManagerSupportClang::onAbstractEditorSupportContentsUpdated(const QString &filePath,
                                                                      const QByteArray &content)
{
    QTC_ASSERT(!filePath.isEmpty(), return);
    m_ipcCommunicator.updateUnsavedFile(filePath, content, 0);
}

void ModelManagerSupportClang::onAbstractEditorSupportRemoved(const QString &filePath)
{
    QTC_ASSERT(!filePath.isEmpty(), return);
    if (!cppModelManager()->cppEditorDocument(filePath)) {
        const QString projectPartId = Utils::projectPartIdForFile(filePath);
        m_ipcCommunicator.unregisterUnsavedFilesForEditor({{filePath, projectPartId}});
    }
}

void addFixItsActionsToMenu(QMenu *menu, const TextEditor::QuickFixOperations &fixItOperations)
{
    foreach (const auto &fixItOperation, fixItOperations) {
        QAction *action = menu->addAction(fixItOperation->description());
        QObject::connect(action, &QAction::triggered, [fixItOperation]() {
            fixItOperation->perform();
        });
    }
}

static int lineToPosition(const QTextDocument *textDocument, int lineNumber)
{
    QTC_ASSERT(textDocument, return 0);
    const QTextBlock textBlock = textDocument->findBlockByLineNumber(lineNumber);
    return textBlock.isValid() ? textBlock.position() - 1 : 0;
}

static TextEditor::AssistInterface createAssistInterface(TextEditor::TextEditorWidget *widget,
                                                         int lineNumber)
{
    return TextEditor::AssistInterface(widget->document(),
                                       lineToPosition(widget->document(), lineNumber),
                                       widget->textDocument()->filePath().toString(),
                                       TextEditor::IdleEditor);
}

void ModelManagerSupportClang::onTextMarkContextMenuRequested(TextEditor::TextEditorWidget *widget,
                                                              int lineNumber,
                                                              QMenu *menu)
{
    QTC_ASSERT(widget, return);
    QTC_ASSERT(lineNumber >= 1, return);
    QTC_ASSERT(menu, return);

    const auto filePath = widget->textDocument()->filePath().toString();
    ClangEditorDocumentProcessor *processor = ClangEditorDocumentProcessor::get(filePath);
    if (processor) {
        const auto assistInterface = createAssistInterface(widget, lineNumber);
        const auto fixItOperations = processor->extraRefactoringOperations(assistInterface);

        addFixItsActionsToMenu(menu, fixItOperations);
    }
}

void ModelManagerSupportClang::onProjectPartsUpdated(ProjectExplorer::Project *project)
{
    QTC_ASSERT(project, return);
    const CppTools::ProjectInfo projectInfo = cppModelManager()->projectInfo(project);
    QTC_ASSERT(projectInfo.isValid(), return);
    m_ipcCommunicator.registerProjectsParts(projectInfo.projectParts());
}

void ModelManagerSupportClang::onProjectPartsRemoved(const QStringList &projectPartIds)
{
    if (!projectPartIds.isEmpty())
        m_ipcCommunicator.unregisterProjectPartsForEditor(projectPartIds);
}

#ifdef QT_TESTLIB_LIB
ModelManagerSupportClang *ModelManagerSupportClang::instance_forTestsOnly()
{
    return m_instance_forTestsOnly;
}
#endif

IpcCommunicator &ModelManagerSupportClang::ipcCommunicator()
{
    return m_ipcCommunicator;
}

QString ModelManagerSupportProviderClang::id() const
{
    return QLatin1String(Constants::CLANG_MODELMANAGERSUPPORT_ID);
}

QString ModelManagerSupportProviderClang::displayName() const
{
    //: Display name
    return QCoreApplication::translate("ClangCodeModel::Internal::ModelManagerSupport",
                                       "Clang");
}

CppTools::ModelManagerSupport::Ptr ModelManagerSupportProviderClang::createModelManagerSupport()
{
    return CppTools::ModelManagerSupport::Ptr(new ModelManagerSupportClang);
}