// Copyright (C) 2016 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GPL-3.0-only WITH Qt-GPL-exception-1.0

#include "clangtoolsdiagnosticview.h"

#include "clangtoolsdiagnosticmodel.h"
#include "clangtoolsprojectsettings.h"
#include "clangtoolssettings.h"
#include "clangtoolstr.h"
#include "clangtoolsutils.h"
#include "diagnosticconfigswidget.h"
#include "inlinesuppresseddiagnostics.h"

#include <coreplugin/editormanager/editormanager.h>
#include <coreplugin/manhattanstyle.h>

#include <cppeditor/cppmodelmanager.h>
#include <cppeditor/cpprefactoringchanges.h>

#include <utils/algorithm.h>
#include <utils/qtcassert.h>
#include <utils/theme/theme.h>
#include <utils/utilsicons.h>

#include <QAction>
#include <QApplication>
#include <QDebug>
#include <QHash>
#include <QHeaderView>
#include <QPainter>
#include <QSet>
#include <QStyledItemDelegate>

#include <set>

using namespace CppEditor;
using namespace Utils;

namespace ClangTools::Internal {

static QString getBaseStyleName()
{
    QStyle *style = QApplication::style();
    if (auto proxyStyle = qobject_cast<QProxyStyle *>(style))
        style = proxyStyle->baseStyle();
    return style->objectName();
}

// Paints the check box indicator disabled if requested by client.
class DiagnosticViewStyle : public ManhattanStyle
{
public:
    DiagnosticViewStyle(const QString &baseStyleName = getBaseStyleName())
        : ManhattanStyle(baseStyleName)
    {}

    void setPaintCheckBoxDisabled(bool paintDisabledCheckbox)
    {
        m_paintCheckBoxDisabled = paintDisabledCheckbox;
    }

    void drawPrimitive(PrimitiveElement element,
                       const QStyleOption *option,
                       QPainter *painter,
                       const QWidget *widget = nullptr) const final
    {
        if (element == QStyle::PE_IndicatorCheckBox && m_paintCheckBoxDisabled) {
            if (const QStyleOptionButton *o = qstyleoption_cast<const QStyleOptionButton *>(
                    option)) {
                QStyleOptionButton myOption = *o;
                myOption.palette.setCurrentColorGroup(QPalette::Disabled);
                ManhattanStyle::drawPrimitive(element, &myOption, painter, widget);
                return;
            }
        }
        ManhattanStyle::drawPrimitive(element, option, painter, widget);
    }

private:
    bool m_paintCheckBoxDisabled = false;
};

// A delegate that allows to paint a disabled check box (indicator).
// This is useful if the rest of the item should not be disabled.
class DiagnosticViewDelegate : public QStyledItemDelegate
{
    Q_OBJECT

public:
    DiagnosticViewDelegate(DiagnosticViewStyle *style, QObject *parent)
        : QStyledItemDelegate(parent)
        ,  m_style(style)
    {}

    void paint(QPainter *painter,
               const QStyleOptionViewItem &option,
               const QModelIndex &index) const final
    {
        const bool paintDisabled = !index.data(ClangToolsDiagnosticModel::CheckBoxEnabledRole)
                                        .toBool();
        if (paintDisabled)
            m_style->setPaintCheckBoxDisabled(true);
        QStyledItemDelegate::paint(painter, option, index);
        if (paintDisabled)
            m_style->setPaintCheckBoxDisabled(false);
    }

private:
    DiagnosticViewStyle *m_style = nullptr;
};

DiagnosticView::DiagnosticView(QWidget *parent)
    : ProjectExplorer::DetailedErrorView(parent)
    , m_style(new DiagnosticViewStyle)
    , m_delegate(new DiagnosticViewDelegate(m_style, this))
{
    header()->hide();
    setSelectionMode(ExtendedSelection);

    const QIcon filterIcon = Utils::Icon({{":/utils/images/filtericon.png",
                                           Utils::Theme::PanelTextColorMid}},
                                         Utils::Icon::Tint).icon();

    m_showFilter = new QAction(Tr::tr("Filter..."), this);
    m_showFilter->setIcon(filterIcon);
    connect(m_showFilter, &QAction::triggered,
            this, &DiagnosticView::showFilter);
    m_clearFilter = new QAction(Tr::tr("Clear Filter"), this);
    m_clearFilter->setIcon(filterIcon);
    connect(m_clearFilter, &QAction::triggered,
            this, &DiagnosticView::clearFilter);
    m_filterForCurrentKind = new QAction(Tr::tr("Filter for This Diagnostic Kind"), this);
    m_filterForCurrentKind->setIcon(filterIcon);
    connect(m_filterForCurrentKind, &QAction::triggered,
            this, &DiagnosticView::filterForCurrentKind);
    m_filterOutCurrentKind = new QAction(Tr::tr("Filter out This Diagnostic Kind"), this);
    m_filterOutCurrentKind->setIcon(filterIcon);
    connect(m_filterOutCurrentKind, &QAction::triggered,
            this, &DiagnosticView::filterOutCurrentKind);

    m_separator = new QAction(this);
    m_separator->setSeparator(true);

    m_separator2 = new QAction(this);
    m_separator2->setSeparator(true);

    m_help = new QAction(Tr::tr("Web Page"), this);
    m_help->setIcon(Utils::Icons::ONLINE.icon());
    connect(m_help, &QAction::triggered,
            this, &DiagnosticView::showHelp);

    m_suppressAction = new QAction(this);
    connect(m_suppressAction, &QAction::triggered,
            this, &DiagnosticView::suppressCurrentDiagnostic);

    m_suppressInlineAction = new QAction(this);
    connect(m_suppressInlineAction, &QAction::triggered,
            this, &DiagnosticView::suppressCurrentDiagnosticInline);

    m_disableChecksAction = new QAction(this);
    connect(m_disableChecksAction, &QAction::triggered,
            this, &DiagnosticView::disableCheckForCurrentDiagnostic);

    installEventFilter(this);

    setStyle(m_style);
    setItemDelegate(m_delegate);
}

void DiagnosticView::scheduleAllFixits(bool schedule)
{
    const FixitStatus newStatus = schedule ? FixitStatus::Scheduled : FixitStatus::NotScheduled;
    const auto proxyModel = qobject_cast<DiagnosticFilterModel *>(model());
    for (int i = 0, count = proxyModel->rowCount(); i < count; ++i) {
        const QModelIndex filePathItemIndex = proxyModel->index(i, 0);
        for (int j = 0, count = proxyModel->rowCount(filePathItemIndex); j < count; ++j) {
            const QModelIndex proxyIndex = proxyModel->index(j, 0, filePathItemIndex);
            const QModelIndex diagnosticItemIndex = proxyModel->mapToSource(proxyIndex);
            auto item = static_cast<DiagnosticItem *>(diagnosticItemIndex.internalPointer());
            item->scheduleOrUnscheduleFixit(newStatus, false);
        }
    }
    emit proxyModel->fixitCountersChanged();
}

DiagnosticView::~DiagnosticView()
{
    delete m_style;
}

void DiagnosticView::suppressCurrentDiagnostic()
{
    const QModelIndexList indexes = selectionModel()->selectedRows();

    // If the original project was closed, we work directly on the filter model, otherwise
    // we go via the project settings.
    const auto filterModel = static_cast<DiagnosticFilterModel *>(model());
    ProjectExplorer::Project * const project = filterModel->project();

    SuppressedDiagnosticsList diags;
    for (const QModelIndex &index : indexes) {
        const Diagnostic diag = model()->data(index, ClangToolsDiagnosticModel::DiagnosticRole)
                .value<Diagnostic>();
        if (!diag.isValid())
            continue;
        if (!project) {
            diags << diag;
            continue;
        }
        FilePath filePath = diag.location.targetFilePath;
        const FilePath relativeFilePath = filePath.relativeChildPath(project->projectDirectory());
        if (!relativeFilePath.isEmpty())
            filePath = relativeFilePath;
        const SuppressedDiagnostic supDiag(filePath, diag.description,
                                           diag.explainingSteps.count());
        diags << SuppressedDiagnostic(filePath, diag.description, diag.explainingSteps.count());
    }

    if (project)
        ClangToolsProjectSettings::getSettings(project)->addSuppressedDiagnostics(diags);
    else
        filterModel->addSuppressedDiagnostics(diags);
}

void DiagnosticView::suppressCurrentDiagnosticInline()
{
    const QModelIndexList indexes = selectionModel()->selectedRows();

    QHash<Utils::FilePath, QHash<int, QStringList>> diagnosticsPerFileAndLine;
    SuppressedDiagnosticsList diags;
    for (const QModelIndex &index : indexes) {
        const Diagnostic diag = model()->data(index, ClangToolsDiagnosticModel::DiagnosticRole)
                                    .value<Diagnostic>();
        if (!diag.isValid())
            continue;
        const bool isApplicable
            = model()->data(index, ClangToolsDiagnosticModel::InlineSuppressableRole).value<bool>();
        if (!isApplicable)
            continue;

        diagnosticsPerFileAndLine[diag.location.targetFilePath][diag.location.target.line]
                << diag.name;

        diags << diag;
    }

    if (diags.isEmpty())
        return;

    const auto filterModel = static_cast<DiagnosticFilterModel *>(model());
    const auto sourceModel = static_cast<ClangToolsDiagnosticModel *>(filterModel->sourceModel());
    CppRefactoringChanges changes(CppModelManager::snapshot());

    for (auto it = diagnosticsPerFileAndLine.cbegin(); it != diagnosticsPerFileAndLine.cend(); ++it) {
        const CppRefactoringFilePtr refactoringFile = changes.cppFile(it.key());
        Utils::ChangeSet changeSet;

        for (auto it2 = it.value().cbegin(); it2 != it.value().cend(); ++it2) {
            const int line = it2.key();
            const QStringList diagNames = it2.value();
            const auto suppressedDiags = sourceModel->createInlineSuppressedDiagnostics();
            const QList<CPlusPlus::Token> tokensForLine = refactoringFile->tokensForLine(line);
            int replaceStart = -1;
            int replaceEnd = -1;
            int insertStart = -1;
            QString prefix;
            QString suffix;
            const QTextDocument * const doc = refactoringFile->document();
            if (!tokensForLine.isEmpty() && tokensForLine.last().isComment()) {
                CPlusPlus::Token trailingComment = tokensForLine.last();
                CPlusPlus::TranslationUnit * const tu
                    = refactoringFile->cppDocument()->translationUnit();
                const int tokenStart = tu->getTokenPositionInDocument(trailingComment, doc);
                const int tokenEnd = tu->getTokenEndPositionInDocument(trailingComment, doc);
                suppressedDiags->fromString(refactoringFile->textOf(tokenStart, tokenEnd));
                if (suppressedDiags->hasError())
                    continue;
                if (suppressedDiags->parsedStartOffset() != -1) {
                    // There was a comment, and it already contained a suppression list.
                    replaceStart = tokenStart + suppressedDiags->parsedStartOffset();
                    replaceEnd = tokenStart + suppressedDiags->parsedEndOffset();
                } else {
                    // There was a comment without a suppression list.
                    prefix = " ";
                    switch (trailingComment.kind()) {
                    case CPlusPlus::T_CPP_COMMENT:
                    case CPlusPlus::T_CPP_DOXY_COMMENT:
                        insertStart = tokenEnd;
                        break;
                    case CPlusPlus::T_COMMENT:
                    case CPlusPlus::T_DOXY_COMMENT:
                        insertStart = tokenEnd - 2;
                        suffix = " ";
                        break;
                    default:
                        QTC_CHECK(false);
                    }
                }
            } else {
                // There was no comment.
                const QTextBlock b = doc->findBlockByNumber(line - 1);
                insertStart = b.position() + b.length() - 1;
                prefix = " // ";
            }
            for (const QString &diagName : diagNames)
                suppressedDiags->addDiagnostic(diagName);
            const QString newText = prefix + suppressedDiags->toString() + suffix;
            if (replaceStart != -1) {
                changeSet.replace(replaceStart, replaceEnd, newText);
            } else {
                QTC_CHECK(insertStart != -1);
                changeSet.insert(insertStart, newText);
            }
        }
        refactoringFile->apply(changeSet);
    }

    filterModel->addSuppressedDiagnostics(diags);
}

void DiagnosticView::disableCheckForCurrentDiagnostic()
{
    std::set<QString> handledNames;
    QList<Diagnostic> diagnostics;
    const QModelIndexList indexes = selectionModel()->selectedRows();
    for (const QModelIndex &index : indexes) {
        const Diagnostic diag = model()->data(index, ClangToolsDiagnosticModel::DiagnosticRole)
                .value<Diagnostic>();
        if (!diag.isValid())
            continue;
        if (!handledNames.insert(diag.name).second)
            continue;
        diagnostics << diag;
    }
    disableChecks(diagnostics);
}

void DiagnosticView::goNext()
{
    const QModelIndex currentIndex = selectionModel()->currentIndex();
    selectIndex(getIndex(currentIndex, Next));
    openEditorForCurrentIndex();
}

void DiagnosticView::goBack()
{
    const QModelIndex currentIndex = selectionModel()->currentIndex();
    selectIndex(getIndex(currentIndex, Previous));
    openEditorForCurrentIndex();
}

QModelIndex DiagnosticView::getIndex(const QModelIndex &index, Direction direction) const
{
    const QModelIndex parentIndex = index.parent();
    QModelIndex followingTopIndex = index;

    if (parentIndex.isValid()) {
        // Use direct sibling for level 2 and 3 items
        const QModelIndex followingIndex = index.sibling(index.row() + direction, 0);
        if (followingIndex.isValid())
            return followingIndex;

        // First/Last level 3 item? Continue on level 2 item.
        if (parentIndex.parent().isValid())
            return direction == Previous ? parentIndex : getIndex(parentIndex, direction);

        followingTopIndex = getTopLevelIndex(parentIndex, direction);
    }

    // Skip top level items without children
    while (!model()->hasChildren(followingTopIndex))
        followingTopIndex = getTopLevelIndex(followingTopIndex, direction);

    // Select first/last level 2 item
    const int row = direction == Next ? 0 : model()->rowCount(followingTopIndex) - 1;
    return model()->index(row, 0, followingTopIndex);
}

QModelIndex DiagnosticView::getTopLevelIndex(const QModelIndex &index, Direction direction) const
{
    QModelIndex following = index.sibling(index.row() + direction, 0);
    if (following.isValid())
        return following;
    const int row = direction == Next ? 0 : model()->rowCount() - 1;
    return model()->index(row, 0);
}

bool DiagnosticView::disableChecksEnabled() const
{
    const QList<QModelIndex> indexes = selectionModel()->selectedIndexes();
    if (indexes.isEmpty())
        return false;
    if (!Utils::anyOf(indexes, &QModelIndex::isValid))
        return false;

    ClangToolsSettings * const settings = ClangToolsSettings::instance();
    const ClangDiagnosticConfigs configs = settings->diagnosticConfigs();
    Utils::Id activeConfigId = settings->runSettings.diagnosticConfigId();
    if (ProjectExplorer::Project * const project
            = static_cast<DiagnosticFilterModel *>(model())->project()) {
        const auto projectSettings = ClangToolsProjectSettings::getSettings(project);
        if (!projectSettings->useGlobalSettings())
            activeConfigId = projectSettings->runSettings.diagnosticConfigId();
    }
    const ClangDiagnosticConfig activeConfig = Utils::findOrDefault(configs,
        [activeConfigId](const ClangDiagnosticConfig &c) { return c.id() == activeConfigId; });

    // If the user has not created any custom configuration yet, then we'll do that for
    // them as an act of kindness. But if custom configurations exist and the default
    // (read-only) one is active, then we don't offer the action, as it's not clear what
    // exactly we should do there.
    if (configs.isEmpty())
        return true;
    if (!activeConfig.id().isValid())
        return false;

    // If all selected diagnostics come from clang-tidy and we prefer a .clang-tidy file, then we do not offer the action.
    if (!settings->runSettings.data().preferConfigFile)
        return true;
    return Utils::anyOf(indexes, [this](const QModelIndex &index) {
        return model()->data(index).toString().startsWith("clazy-");
    });
}

QList<QAction *> DiagnosticView::customActions() const
{
    const QModelIndex currentIndex = selectionModel()->currentIndex();

    const bool hasMultiSelection = selectionModel()->selectedIndexes().size() > 1;
    const bool isDiagnosticItem = currentIndex.parent().isValid();
    const QString docUrl
        = model()->data(currentIndex, ClangToolsDiagnosticModel::DocumentationUrlRole).toString();
    m_help->setEnabled(isDiagnosticItem && !docUrl.isEmpty() && !hasMultiSelection);
    m_filterForCurrentKind->setEnabled(isDiagnosticItem && !hasMultiSelection);
    m_filterOutCurrentKind->setEnabled(isDiagnosticItem && !hasMultiSelection);
    m_suppressAction->setEnabled(isDiagnosticItem || hasMultiSelection);
    m_suppressAction->setText(hasMultiSelection ? Tr::tr("Suppress Selected Diagnostics")
                                                : Tr::tr("Suppress This Diagnostic"));
    m_suppressInlineAction->setEnabled(isDiagnosticItem || hasMultiSelection);
    m_suppressInlineAction->setText(hasMultiSelection ? Tr::tr("Suppress Selected Diagnostics Inline")
                                                      : Tr::tr("Suppress This Diagnostic Inline"));
    m_disableChecksAction->setEnabled(disableChecksEnabled());
    m_disableChecksAction->setText(hasMultiSelection ? Tr::tr("Disable These Checks")
                                                     : Tr::tr("Disable This Check"));

    return {
        m_help,
        m_separator,
        m_showFilter,
        m_clearFilter,
        m_filterForCurrentKind,
        m_filterOutCurrentKind,
        m_separator2,
        m_suppressAction,
        m_suppressInlineAction,
        m_disableChecksAction
    };
}

bool DiagnosticView::eventFilter(QObject *watched, QEvent *event)
{
    switch (event->type()) {
    case QEvent::KeyRelease: {
        const int key = static_cast<QKeyEvent *>(event)->key();
        switch (key) {
        case Qt::Key_Return:
        case Qt::Key_Enter:
            openEditorForCurrentIndex();
        }
        return true;
    }
    default:
        return QAbstractItemView::eventFilter(watched, event);
    }
}

void DiagnosticView::mouseDoubleClickEvent(QMouseEvent *event)
{
    openEditorForCurrentIndex();
    ProjectExplorer::DetailedErrorView::mouseDoubleClickEvent(event);
}

void DiagnosticView::openEditorForCurrentIndex()
{
    const QVariant v = model()->data(currentIndex(), ProjectExplorer::DetailedErrorView::LocationRole);
    Link loc = v.value<Link>();
    if (loc.hasValidTarget())
        Core::EditorManager::openEditorAt(loc);
}

} // namespace ClangTools::Internal

#include "clangtoolsdiagnosticview.moc"
