watchhandler.cpp

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**
** Copyright (C) 2012 Digia Plc and/or its subsidiary(-ies).
** Contact: http://www.qt-project.org/legal
**
** This file is part of Qt Creator.
**
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** Foundation and appearing in the file LICENSE.LGPL included in the
** packaging of this file.  Please review the following information to
** ensure the GNU Lesser General Public License version 2.1 requirements
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#include "watchhandler.h"

#include "breakhandler.h"
#include "debuggerinternalconstants.h"
#include "debuggeractions.h"
#include "debuggercore.h"
#include "debuggerengine.h"
#include "debuggerdialogs.h"
#include "watchutils.h"

#include <utils/qtcassert.h>
#include <utils/savedaction.h>

#include <cplusplus/CppRewriter.h>

#include <QDebug>
#include <QEvent>
#include <QFile>
#include <QPointer>
#include <QProcess>
#include <QTextStream>
#include <QtAlgorithms>

#include <QLabel>
#include <QTextEdit>
#include <QTabWidget>

#include <ctype.h>
#include <utils/qtcassert.h>

//#define USE_WATCH_MODEL_TEST 0
//#define USE_EXPENSIVE_CHECKS 0

#if USE_WATCH_MODEL_TEST
#include "modeltest.h"
#endif

namespace Debugger {
namespace Internal {

// Creates debug output for accesses to the model.
enum { debugModel = 0 };

#define MODEL_DEBUG(s) do { if (debugModel) qDebug() << s; } while (0)

#if USE_EXPENSIVE_CHECKS
#define CHECK(s) s
#else
#define CHECK(s)
#endif


static QHash<QByteArray, int> theWatcherNames;
static QHash<QByteArray, int> theTypeFormats;
static QHash<QByteArray, int> theIndividualFormats;
static int theUnprintableBase = -1;


static QByteArray stripForFormat(const QByteArray &ba)
{
    QByteArray res;
    res.reserve(ba.size());
    int inArray = 0;
    for (int i = 0; i != ba.size(); ++i) {
        const char c = ba.at(i);
        if (c == '<')
            break;
        if (c == '[')
            ++inArray;
        if (c == ']')
            --inArray;
        if (c == ' ')
            continue;
        if (c == '&') // Treat references like the referenced type.
            continue;
        if (inArray && c >= '0' && c <= '9')
            continue;
        res.append(c);
    }
    return res;
}

////////////////////////////////////////////////////////////////////
//
// WatchItem
//
////////////////////////////////////////////////////////////////////

// Used to make sure the item cache is notified of construction and
// destruction of items.

class WatchItem;
typedef QList<WatchItem *> WatchItems;

WatchItem *itemConstructor(WatchModel *model, const QByteArray &iname);
void itemDestructor(WatchModel *model, WatchItem *item);

class WatchItem : public WatchData
{
public:
    WatchItem *parent; // Not owned.
    WatchItems children; // Not owned. Handled via itemDestructor().

private:
    friend WatchItem *itemConstructor(WatchModel *model, const QByteArray &iname);
    friend void itemDestructor(WatchModel *model, WatchItem *item);

    WatchItem() { parent = 0; }
    ~WatchItem() {}
    WatchItem(const WatchItem &); // Not implemented.
};

///////////////////////////////////////////////////////////////////////
//
// WatchModel
//
///////////////////////////////////////////////////////////////////////

class WatchModel : public QAbstractItemModel
{
    Q_OBJECT

private:
    explicit WatchModel(WatchHandler *handler);
    ~WatchModel();

    friend WatchItem *itemConstructor(WatchModel *model, const QByteArray &iname);
    friend void itemDestructor(WatchModel *model, WatchItem *item);

public:
    int rowCount(const QModelIndex &idx = QModelIndex()) const;
    int columnCount(const QModelIndex &idx) const;

signals:
    void currentIndexRequested(const QModelIndex &idx);
    void itemIsExpanded(const QModelIndex &idx);

private:
    QVariant data(const QModelIndex &idx, int role) const;
    bool setData(const QModelIndex &idx, const QVariant &value, int role);
    QModelIndex index(int, int, const QModelIndex &idx) const;
    QModelIndex parent(const QModelIndex &idx) const;
    bool hasChildren(const QModelIndex &idx) const;
    Qt::ItemFlags flags(const QModelIndex &idx) const;
    QVariant headerData(int section, Qt::Orientation orientation,
        int role = Qt::DisplayRole) const;
    bool canFetchMore(const QModelIndex &parent) const;
    void fetchMore(const QModelIndex &parent);

    void invalidateAll(const QModelIndex &parentIndex = QModelIndex());
    void resetValueCacheRecursively(WatchItem *item);

    WatchItem *createItem(const QByteArray &iname, const QString &name, WatchItem *parent);

    friend class WatchHandler;

    WatchItem *watchItem(const QModelIndex &) const;
    QModelIndex watchIndex(const WatchItem *needle) const;
    QModelIndex watchIndexHelper(const WatchItem *needle,
        const WatchItem *parentItem, const QModelIndex &parentIndex) const;

    void insertDataItem(const WatchData &data, bool destructive);
    Q_SLOT void reinsertAllData();
    void reinsertAllDataHelper(WatchItem *item, QList<WatchData> *data);
    bool ancestorChanged(const QSet<QByteArray> &parentINames, WatchItem *item) const;
    void insertBulkData(const QList<WatchData> &data);
    QString displayForAutoTest(const QByteArray &iname) const;
    void reinitialize(bool includeInspectData = false);
    void destroyItem(WatchItem *item); // With model notification.
    void destroyChildren(WatchItem *item); // With model notification.
    void destroyHelper(const WatchItems &items); // Without model notification.
    void emitDataChanged(int column,
        const QModelIndex &parentIndex = QModelIndex());

    friend QDebug operator<<(QDebug d, const WatchModel &m);

    void dump();
    void dumpHelper(WatchItem *item);
    Q_SLOT void emitAllChanged();

    void showInEditorHelper(QString *contents, WatchItem *item, int level);
    void setCurrentItem(const QByteArray &iname);

    QString displayType(const WatchData &typeIn) const;
    QString formattedValue(const WatchData &data) const;
    QString removeInitialNamespace(QString str) const;
    QString removeNamespaces(QString str) const;
    void formatRequests(QByteArray *out, const WatchItem *item) const;
    DebuggerEngine *engine() const;
    QString display(const WatchItem *item, int col) const;
    int itemFormat(const WatchData &data) const;
    bool contentIsValid() const;

    WatchHandler *m_handler; // Not owned.

    WatchItem *m_root; // Owned.
    WatchItem *m_localsRoot; // Not owned.
    WatchItem *m_inspectorRoot; // Not owned.
    WatchItem *m_watchRoot; // Not owned.
    WatchItem *m_returnRoot; // Not owned.
    WatchItem *m_tooltipRoot; // Not owned.

    QSet<QByteArray> m_expandedINames;
    QSet<QByteArray> m_fetchTriggered;

    QStringList typeFormatList(const WatchData &data) const;
    TypeFormats m_reportedTypeFormats;

    // QWidgets and QProcesses taking care of special displays.
    typedef QMap<QByteArray, QPointer<QObject> > EditHandlers;
    EditHandlers m_editHandlers;

    WatchItem *createItem(const QByteArray &iname);
    WatchItem *createItem(const WatchData &data);
    void assignData(WatchItem *item, const WatchData &data);
    WatchItem *findItem(const QByteArray &iname) const;
    friend class WatchItem;
    typedef QHash<QByteArray, WatchItem *> Cache;
    Cache m_cache;
    typedef QHash<QByteArray, QString> ValueCache;
    ValueCache m_valueCache;

    #if USE_EXPENSIVE_CHECKS
    QHash<const WatchItem *, QByteArray> m_cache2;
    void checkTree();
    void checkItem(const WatchItem *item) const;
    void checkTree(WatchItem *item, QSet<QByteArray> *inames);
    #endif
};

WatchModel::WatchModel(WatchHandler *handler)
    : m_handler(handler)
{
    m_root = createItem(QByteArray(), tr("Root"), 0);
    // Note: Needs to stay
    m_localsRoot = createItem("local", tr("Locals"), m_root);
    m_inspectorRoot = createItem("inspect", tr("Inspector"), m_root);
    m_watchRoot = createItem("watch", tr("Expressions"), m_root);
    m_returnRoot = createItem("return", tr("Return Value"), m_root);
    m_tooltipRoot = createItem("tooltip", tr("Tooltip"), m_root);

    connect(debuggerCore()->action(SortStructMembers), SIGNAL(valueChanged(QVariant)),
        SLOT(reinsertAllData()));
    connect(debuggerCore()->action(ShowStdNamespace), SIGNAL(valueChanged(QVariant)),
        SLOT(reinsertAllData()));
    connect(debuggerCore()->action(ShowQtNamespace), SIGNAL(valueChanged(QVariant)),
        SLOT(reinsertAllData()));
}

WatchModel::~WatchModel()
{
    CHECK(checkItem(m_root));
    destroyChildren(m_root);
    itemDestructor(this, m_root);
    QTC_CHECK(m_cache.isEmpty());
}

WatchItem *itemConstructor(WatchModel *model, const QByteArray &iname)
{
    QTC_CHECK(!model->m_cache.contains(iname));
    WatchItem *item = new WatchItem();
    item->iname = iname;
    model->m_cache[iname] = item;
    CHECK(model->m_cache2[item] = iname);
    CHECK(model->checkItem(item));
    return item;
}

void itemDestructor(WatchModel *model, WatchItem *item)
{
    QTC_ASSERT(model->m_cache.value(item->iname) == item, return);
    CHECK(model->checkItem(item));
    CHECK(model->m_cache2.remove(item));
    model->m_cache.remove(item->iname);
    delete item;
}

WatchItem *WatchModel::createItem(const QByteArray &iname, const QString &name, WatchItem *parent)
{
    WatchItem *item = itemConstructor(this, iname);
    item->name = name;
    item->hasChildren = true; // parent == 0;
    item->state = 0;
    item->parent = parent;
    if (parent)
        parent->children.append(item);
    return item;
}

void WatchModel::reinitialize(bool includeInspectData)
{
    CHECK(checkTree());
    //MODEL_DEBUG("REMOVING " << n << " CHILDREN OF " << m_root->iname);
    QTC_CHECK(m_root->children.size() == 5);
    destroyChildren(m_localsRoot);
    destroyChildren(m_watchRoot);
    destroyChildren(m_returnRoot);
    destroyChildren(m_tooltipRoot);
    if (includeInspectData) {
        destroyChildren(m_inspectorRoot);
        QTC_CHECK(m_cache.size() == 6);
    }
    CHECK(checkTree());
}

void WatchModel::emitAllChanged()
{
    emit layoutChanged();
}

DebuggerEngine *WatchModel::engine() const
{
    return m_handler->m_engine;
}

void WatchModel::dump()
{
    qDebug() << "\n";
    foreach (WatchItem *child, m_root->children)
        dumpHelper(child);
}

void WatchModel::dumpHelper(WatchItem *item)
{
    qDebug() << "ITEM: " << item->iname
        << (item->parent ? item->parent->iname : "<none>");
    foreach (WatchItem *child, item->children)
        dumpHelper(child);
}

void WatchModel::destroyHelper(const WatchItems &items)
{
    for (int i = items.size(); --i >= 0; ) {
        WatchItem *item = items.at(i);
        destroyHelper(item->children);
        itemDestructor(this, item);
    }
}

void WatchModel::destroyItem(WatchItem *item)
{
    const QByteArray iname = item->iname;
    CHECK(checkTree());
    QTC_ASSERT(m_cache.contains(iname), return);

    // Deregister from model and parent.
    // It's sufficient to do this non-recursively.
    WatchItem *parent = item->parent;
    QTC_ASSERT(parent, return);
    QModelIndex parentIndex = watchIndex(parent);
    const int i = parent->children.indexOf(item);
    //MODEL_DEBUG("NEED TO REMOVE: " << item->iname << "AT" << n);
    beginRemoveRows(parentIndex, i, i);
    parent->children.removeAt(i);
    endRemoveRows();

    // Destroy contents.
    destroyHelper(item->children);
    itemDestructor(this, item);
    QTC_ASSERT(!m_cache.contains(iname), return);
    CHECK(checkTree());
}

void WatchModel::destroyChildren(WatchItem *item)
{
    CHECK(checkTree());
    QTC_ASSERT(m_cache.contains(item->iname), return);
    if (item->children.isEmpty())
        return;

    WatchItems items = item->children;

    // Deregister from model and parent.
    // It's sufficient to do this non-recursively.
    QModelIndex idx = watchIndex(item);
    beginRemoveRows(idx, 0, items.size() - 1);
    item->children.clear();
    endRemoveRows();

    // Destroy contents.
    destroyHelper(items);
    CHECK(checkTree());
}

WatchItem *WatchModel::findItem(const QByteArray &iname) const
{
    return m_cache.value(iname, 0);
}

WatchItem *WatchModel::createItem(const WatchData &data)
{
    WatchItem *item = itemConstructor(this, data.iname);
    static_cast<WatchData &>(*item) = data;
    return item;
}

void WatchModel::assignData(WatchItem *item, const WatchData &data)
{
    CHECK(checkItem(item));
    QTC_ASSERT(data.iname == item->iname,
        m_cache.remove(item->iname);
        m_cache[data.iname] = item);
    static_cast<WatchData &>(*item) = data;
    CHECK(checkItem(item));
}

void WatchModel::reinsertAllData()
{
    QList<WatchData> list;
    reinsertAllDataHelper(m_root, &list);
    reinitialize(true);
    insertBulkData(list);
}

void WatchModel::reinsertAllDataHelper(WatchItem *item, QList<WatchData> *data)
{
    data->append(*item);
    data->back().setAllUnneeded();
    foreach (WatchItem *child, item->children)
        reinsertAllDataHelper(child, data);
}

static QByteArray parentName(const QByteArray &iname)
{
    const int pos = iname.lastIndexOf('.');
    return pos == -1 ? QByteArray() : iname.left(pos);
}

static QString niceTypeHelper(const QByteArray &typeIn)
{
    typedef QMap<QByteArray, QString> Cache;
    static Cache cache;
    const Cache::const_iterator it = cache.constFind(typeIn);
    if (it != cache.constEnd())
        return it.value();
    const QString simplified = CPlusPlus::simplifySTLType(QLatin1String(typeIn));
    cache.insert(typeIn, simplified); // For simplicity, also cache unmodified types
    return simplified;
}

QString WatchModel::removeNamespaces(QString str) const
{
    if (!debuggerCore()->boolSetting(ShowStdNamespace))
        str.remove(QLatin1String("std::"));
    if (!debuggerCore()->boolSetting(ShowQtNamespace)) {
        const QString qtNamespace = QString::fromLatin1(engine()->qtNamespace());
        if (!qtNamespace.isEmpty())
            str.remove(qtNamespace);
    }
    return str;
}

QString WatchModel::removeInitialNamespace(QString str) const
{
    if (str.startsWith(QLatin1String("std::"))
            && debuggerCore()->boolSetting(ShowStdNamespace))
        str = str.mid(5);
    if (!debuggerCore()->boolSetting(ShowQtNamespace)) {
        const QByteArray qtNamespace = engine()->qtNamespace();
        if (!qtNamespace.isEmpty() && str.startsWith(QLatin1String(qtNamespace)))
            str = str.mid(qtNamespace.size());
    }
    return str;
}

QString WatchModel::displayType(const WatchData &data) const
{
    QString base = data.displayedType.isEmpty()
        ? niceTypeHelper(data.type)
        : data.displayedType;
    if (data.bitsize)
        base += QString::fromLatin1(":%1").arg(data.bitsize);
    base.remove(QLatin1Char('\''));
    return base;
}

static int formatToIntegerBase(int format)
{
    switch (format) {
        case HexadecimalFormat:
            return 16;
        case BinaryFormat:
            return 2;
        case OctalFormat:
            return 8;
    }
    return 10;
}

template <class IntType> QString reformatInteger(IntType value, int format)
{
    switch (format) {
        case HexadecimalFormat:
            return QLatin1String("(hex) ") + QString::number(value, 16);
        case BinaryFormat:
            return QLatin1String("(bin) ") + QString::number(value, 2);
        case OctalFormat:
            return QLatin1String("(oct) ") + QString::number(value, 8);
    }
    return QString::number(value); // not reached
}

// Format printable (char-type) characters
static QString reformatCharacter(int code, int format)
{
    const QString codeS = reformatInteger(code, format);
    if (code < 0) // Append unsigned value.
        return codeS + QLatin1String(" / ") + reformatInteger(256 + code, format);
    const QChar c = QLatin1Char(code);
    if (c.isPrint())
        return codeS + QLatin1String(" '") + c + QLatin1Char('\'');
    switch (code) {
    case 0:
        return codeS + QLatin1String(" '\\0'");
    case '\r':
        return codeS + QLatin1String(" '\\r'");
    case '\t':
        return codeS + QLatin1String(" '\\t'");
    case '\n':
        return codeS + QLatin1String(" '\\n'");
    }
    return codeS;
}

static QString quoteUnprintable(const QString &str)
{
    if (WatchHandler::unprintableBase() == 0)
        return str;

    QString encoded;
    if (WatchHandler::unprintableBase() == -1) {
        foreach (const QChar c, str) {
            int u = c.unicode();
            if (c.isPrint())
                encoded += c;
            else if (u == '\r')
                encoded += QLatin1String("\\r");
            else if (u == '\t')
                encoded += QLatin1String("\\t");
            else if (u == '\n')
                encoded += QLatin1String("\\n");
            else
                encoded += QString::fromLatin1("\\%1")
                    .arg(c.unicode(), 3, 8, QLatin1Char('0'));
        }
        return encoded;
    }

    foreach (const QChar c, str) {
        if (c.isPrint()) {
            encoded += c;
        } else if (WatchHandler::unprintableBase() == 8) {
            encoded += QString::fromLatin1("\\%1")
                .arg(c.unicode(), 3, 8, QLatin1Char('0'));
        } else {
            encoded += QString::fromLatin1("\\u%1")
                .arg(c.unicode(), 4, 16, QLatin1Char('0'));
        }
    }
    return encoded;
}

static QString translate(const QString &str)
{
    if (str.startsWith(QLatin1Char('<'))) {
        if (str == QLatin1String("<Edit>"))
            return WatchHandler::tr("<Edit>");
        if (str == QLatin1String("<empty>"))
            return WatchHandler::tr("<empty>");
        if (str == QLatin1String("<uninitialized>"))
            return WatchHandler::tr("<uninitialized>");
        if (str == QLatin1String("<invalid>"))
            return WatchHandler::tr("<invalid>");
        if (str == QLatin1String("<not accessible>"))
            return WatchHandler::tr("<not accessible>");
        if (str.endsWith(QLatin1String(" items>"))) {
            // '<10 items>' or '<>10 items>' (more than)
            bool ok;
            const bool moreThan = str.at(1) == QLatin1Char('>');
            const int numberPos = moreThan ? 2 : 1;
            const int len = str.indexOf(QLatin1Char(' ')) - numberPos;
            const int size = str.mid(numberPos, len).toInt(&ok);
            QTC_ASSERT(ok, qWarning("WatchHandler: Invalid item count '%s'",
                qPrintable(str)));
            return moreThan ?
                     WatchHandler::tr("<more than %n items>", 0, size) :
                     WatchHandler::tr("<%n items>", 0, size);
        }
    }
    return quoteUnprintable(str);
}

QString WatchModel::formattedValue(const WatchData &data) const
{
    const QString &value = data.value;

    if (data.type == "bool") {
        if (value == QLatin1String("0"))
            return QLatin1String("false");
        if (value == QLatin1String("1"))
            return QLatin1String("true");
        return value;
    }

    if (isIntType(data.type)) {
        if (value.isEmpty())
            return value;
        // Do not reformat booleans (reported as 'true, false').
        const QChar firstChar = value.at(0);
        if (!firstChar.isDigit() && firstChar != QLatin1Char('-'))
            return value;

        // Append quoted, printable character also for decimal.
        const int format = itemFormat(data);
        if (data.type.endsWith("char")) {
            bool ok;
            const int code = value.toInt(&ok);
            return ok ? reformatCharacter(code, format) : value;
        }
        // Rest: Leave decimal as is
        if (format <= 0)
            return value;
        // Evil hack, covers 'unsigned' as well as quint64.
        if (data.type.contains('u'))
            return reformatInteger(value.toULongLong(0, 0), format);
        return reformatInteger(value.toLongLong(), format);
    }

    if (data.type == "va_list")
        return value;

    if (!isPointerType(data.type) && !data.isVTablePointer()) {
        bool ok = false;
        qulonglong integer = value.toULongLong(&ok, 0);
        if (ok) {
            const int format = itemFormat(data);
            return reformatInteger(integer, format);
        }
    }

    return translate(value);
}

// Get a pointer address from pointer values reported by the debugger.
// Fix CDB formatting of pointers "0x00000000`000003fd class foo *", or
// "0x00000000`000003fd "Hallo"", or check gdb formatting of characters.
static inline quint64 pointerValue(QString data)
{
    const int blankPos = data.indexOf(QLatin1Char(' '));
    if (blankPos != -1)
        data.truncate(blankPos);
    data.remove(QLatin1Char('`'));
    return data.toULongLong(0, 0);
}

// Return the type used for editing
static inline int editType(const WatchData &d)
{
    if (d.type == "bool")
        return QVariant::Bool;
    if (isIntType(d.type))
        return d.type.contains('u') ? QVariant::ULongLong : QVariant::LongLong;
    if (isFloatType(d.type))
        return QVariant::Double;
    // Check for pointers using hex values (0xAD00 "Hallo")
    if (isPointerType(d.type) && d.value.startsWith(QLatin1String("0x")))
        return QVariant::ULongLong;
   return QVariant::String;
}

// Convert to editable (see above)
static inline QVariant editValue(const WatchData &d)
{
    switch (editType(d)) {
    case QVariant::Bool:
        return d.value != QLatin1String("0") && d.value != QLatin1String("false");
    case QVariant::ULongLong:
        if (isPointerType(d.type)) // Fix pointer values (0xAD00 "Hallo" -> 0xAD00)
            return QVariant(pointerValue(d.value));
        return QVariant(d.value.toULongLong());
    case QVariant::LongLong:
        return QVariant(d.value.toLongLong());
    case QVariant::Double:
        return QVariant(d.value.toDouble());
    default:
        break;
    }
    // Some string value: '0x434 "Hallo"':
    // Remove quotes and replace newlines, which will cause line edit troubles.
    QString stringValue = d.value;
    if (stringValue.endsWith(QLatin1Char('"'))) {
        const int leadingDoubleQuote = stringValue.indexOf(QLatin1Char('"'));
        if (leadingDoubleQuote != stringValue.size() - 1) {
            stringValue.truncate(stringValue.size() - 1);
            stringValue.remove(0, leadingDoubleQuote + 1);
            stringValue.replace(QLatin1String("\n"), QLatin1String("\\n"));
        }
    }
    return QVariant(translate(stringValue));
}

bool WatchModel::canFetchMore(const QModelIndex &idx) const
{
    if (!idx.isValid())
        return false;
    WatchItem *item = watchItem(idx);
    QTC_ASSERT(item, return false);
    if (!contentIsValid() && !item->isInspect())
        return false;
    if (!item->iname.contains('.'))
        return false;
    return !m_fetchTriggered.contains(item->iname);
}

void WatchModel::fetchMore(const QModelIndex &idx)
{
    if (!idx.isValid())
        return; // Triggered by ModelTester.
    WatchItem *item = watchItem(idx);
    QTC_ASSERT(item, return);
    QTC_ASSERT(!m_fetchTriggered.contains(item->iname), return);
    m_expandedINames.insert(item->iname);
    m_fetchTriggered.insert(item->iname);
    if (item->children.isEmpty()) {
        WatchData data = *item;
        data.setChildrenNeeded();
        WatchUpdateFlags flags;
        flags.tryIncremental = true;
        engine()->updateWatchData(data, flags);
    }
}

QModelIndex WatchModel::index(int row, int column, const QModelIndex &parent) const
{
    if (!hasIndex(row, column, parent))
        return QModelIndex();

    const WatchItem *item = watchItem(parent);
    QTC_ASSERT(item, return QModelIndex());
    if (row >= item->children.size())
        return QModelIndex();
    return createIndex(row, column, (void*)(item->children.at(row)));
}

QModelIndex WatchModel::parent(const QModelIndex &idx) const
{
    if (!idx.isValid())
        return QModelIndex();

    const WatchItem *item = watchItem(idx);
    const WatchItem *parent = item->parent;
    if (!parent || parent == m_root)
        return QModelIndex();

    const WatchItem *grandparent = parent->parent;
    if (!grandparent)
        return QModelIndex();

    const WatchItems &uncles = grandparent->children;
    for (int i = 0, n = uncles.size(); i < n; ++i)
        if (uncles.at(i) == parent)
            return createIndex(i, 0, (void*) parent);

    return QModelIndex();
}

int WatchModel::rowCount(const QModelIndex &idx) const
{
    if (!idx.isValid())
        return m_root->children.size();
    if (idx.column() > 0)
        return 0;
    return watchItem(idx)->children.size();
}

int WatchModel::columnCount(const QModelIndex &idx) const
{
    Q_UNUSED(idx)
    return 3;
}

bool WatchModel::hasChildren(const QModelIndex &parent) const
{
    WatchItem *item = watchItem(parent);
    return !item || item->hasChildren;
}

WatchItem *WatchModel::watchItem(const QModelIndex &idx) const
{
    WatchItem *item = idx.isValid()
        ? static_cast<WatchItem*>(idx.internalPointer()) : m_root;
    CHECK(checkItem(item));
    return item;
}

QModelIndex WatchModel::watchIndex(const WatchItem *item) const
{
    CHECK(checkItem(item));
    return watchIndexHelper(item, m_root, QModelIndex());
}

QModelIndex WatchModel::watchIndexHelper(const WatchItem *needle,
    const WatchItem *parentItem, const QModelIndex &parentIndex) const
{
    if (needle == parentItem)
        return parentIndex;
    for (int i = parentItem->children.size(); --i >= 0; ) {
        const WatchItem *childItem = parentItem->children.at(i);
        QModelIndex childIndex = index(i, 0, parentIndex);
        QModelIndex idx = watchIndexHelper(needle, childItem, childIndex);
        if (idx.isValid())
            return idx;
    }
    return QModelIndex();
}

void WatchModel::emitDataChanged(int column, const QModelIndex &parentIndex)
{
    QModelIndex idx1 = index(0, column, parentIndex);
    QModelIndex idx2 = index(rowCount(parentIndex) - 1, column, parentIndex);
    if (idx1.isValid() && idx2.isValid())
        emit dataChanged(idx1, idx2);
    //qDebug() << "CHANGING:\n" << idx1 << "\n" << idx2 << "\n"
    //    << data(parentIndex, INameRole).toString();
    for (int i = rowCount(parentIndex); --i >= 0; )
        emitDataChanged(column, index(i, 0, parentIndex));
}

void WatchModel::invalidateAll(const QModelIndex &parentIndex)
{
    QModelIndex idx1 = index(0, 0, parentIndex);
    QModelIndex idx2 = index(rowCount(parentIndex) - 1, columnCount(parentIndex) - 1, parentIndex);
    if (idx1.isValid() && idx2.isValid())
        emit dataChanged(idx1, idx2);
}

void WatchModel::resetValueCacheRecursively(WatchItem *item)
{
    m_valueCache[item->iname] = item->value;
    const WatchItems &items = item->children;
    for (int i = items.size(); --i >= 0; )
        resetValueCacheRecursively(items.at(i));
}

// Truncate value for item view, maintaining quotes.
static QString truncateValue(QString v)
{
    enum { maxLength = 512 };
    if (v.size() < maxLength)
        return v;
    const bool isQuoted = v.endsWith(QLatin1Char('"')); // check for 'char* "Hallo"'
    v.truncate(maxLength);
    v += isQuoted ? QLatin1String("...\"") : QLatin1String("...");
    return v;
}

int WatchModel::itemFormat(const WatchData &data) const
{
    const int individualFormat = theIndividualFormats.value(data.iname, -1);
    if (individualFormat != -1)
        return individualFormat;
    return theTypeFormats.value(stripForFormat(data.type), -1);
}

bool WatchModel::contentIsValid() const
{
    // FIXME:
    // inspector doesn't follow normal beginCycle()/endCycle()
    //if (m_type == InspectWatch)
    //    return true;
    return m_handler->m_contentsValid;
}

#if USE_EXPENSIVE_CHECKS
void WatchModel::checkTree()
{
    QSet<QByteArray> inames;
    checkTree(m_root, &inames);
    QSet<QByteArray> current = m_cache.keys().toSet();
    Q_ASSERT(inames == current);
}

void WatchModel::checkTree(WatchItem *item, QSet<QByteArray> *inames)
{
    checkItem(item);
    inames->insert(item->iname);
    for (int i = 0, n = item->children.size(); i != n; ++i)
        checkTree(item->children.at(i), inames);
}

void WatchModel::checkItem(const WatchItem *item) const
{
    Q_ASSERT(item->children.size() < 1000 * 1000);
    Q_ASSERT(m_cache2.contains(item));
    Q_ASSERT(m_cache2.value(item) == item->iname);
    Q_ASSERT(m_cache.value(item->iname) == item);
}
#endif

static QString expression(const WatchItem *item)
{
    if (!item->exp.isEmpty())
         return QString::fromLatin1(item->exp);
    if (item->address && !item->type.isEmpty()) {
        return QString::fromLatin1("*(%1*)%2").
                arg(QLatin1String(item->type), QLatin1String(item->hexAddress()));
    }
    if (const WatchItem *parent = item->parent) {
        if (!parent->exp.isEmpty())
           return QString::fromLatin1("(%1).%2")
            .arg(QString::fromLatin1(parent->exp), item->name);
    }
    return QString();
}

QString WatchModel::display(const WatchItem *item, int col) const
{
    QString result;
    switch (col) {
        case 0:
            if (item->parent == m_watchRoot && item->name.isEmpty())
                result = tr("<Edit>");
            else if (item->parent == m_returnRoot)
                result = tr("returned value");
            else if (item->name == QLatin1String("*"))
                result = QLatin1Char('*') + item->parent->name;
            else
                result = removeInitialNamespace(item->name);
            break;
        case 1:
            result = removeInitialNamespace(
                truncateValue(formattedValue(*item)));
            // Append referencing address unless the value contains it.
            if (item->referencingAddress) {
                if (result.startsWith(QLatin1String("0x"))) {
                    result.prepend(QLatin1Char('@'));
                } else {
                    result += QLatin1String(" @");
                    result += QString::fromLatin1(item->hexReferencingAddress());
                }
            }
            break;
        case 2:
            result = removeNamespaces(displayType(*item));
            break;
        default:
            break;
    }
    return result;
}

QString WatchModel::displayForAutoTest(const QByteArray &iname) const
{
    WatchItem *item = findItem(iname);
    if (item)
        return display(item, 1) + QLatin1Char(' ') + display(item, 2);
    return QString();
}

QVariant WatchModel::data(const QModelIndex &idx, int role) const
{
    if (!idx.isValid())
        return QVariant(); // Triggered by ModelTester.

    const WatchItem *item = watchItem(idx);
    const WatchItem &data = *item;

    switch (role) {
        case LocalsEditTypeRole:
            return QVariant(editType(data));

        case LocalsNameRole:
            return QVariant(data.name);

        case LocalsIntegerBaseRole:
            if (isPointerType(data.type)) // Pointers using 0x-convention
                return QVariant(16);
            return QVariant(formatToIntegerBase(itemFormat(data)));

        case Qt::EditRole: {
            switch (idx.column()) {
                case 0:
                    return QVariant(expression(item));
                case 1:
                    return editValue(data);
                case 2:
                    // FIXME:: To be tested: Can debuggers handle those?
                    if (!data.displayedType.isEmpty())
                        return data.displayedType;
                    return QString::fromUtf8(data.type);
                default:
                    break;
            }
        }

        case Qt::DisplayRole:
            return display(item, idx.column());

        case Qt::ToolTipRole:
            return debuggerCore()->boolSetting(UseToolTipsInLocalsView)
                ? data.toToolTip() : QVariant();

        case Qt::ForegroundRole: {
            static const QVariant red(QColor(200, 0, 0));
            static const QVariant gray(QColor(140, 140, 140));
            if (idx.column() == 1) {
                if (!data.valueEnabled || (!contentIsValid() && !data.isInspect()))
                    return gray;
                if (data.value != m_valueCache.value(data.iname))
                    return red;
            }
            break;
        }

        case LocalsExpressionRole:
            return QVariant(expression(item));

        case LocalsRawExpressionRole:
            return data.exp;

        case LocalsINameRole:
            return data.iname;

        case LocalsExpandedRole:
            return m_expandedINames.contains(data.iname);

        case LocalsTypeFormatListRole:
            return typeFormatList(data);

        case LocalsTypeRole:
            return removeNamespaces(displayType(data));

        case LocalsRawTypeRole:
            return QString::fromLatin1(data.type);

        case LocalsTypeFormatRole:
            return theTypeFormats.value(stripForFormat(data.type), -1);

        case LocalsIndividualFormatRole:
            return theIndividualFormats.value(data.iname, -1);