Implement a common interface for help viewers.

Both implementations are now split into two source files, based on the
base class type. They share also a commen implementation, but the class
interface looks now clean to the outside. Adopt other classes for use.

src/plugins/help/helpviewer.cpp

+/**************************************************************************
+**
+** This file is part of Qt Creator
+**
+** Copyright (c) 2010 Nokia Corporation and/or its subsidiary(-ies).
+**
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** Commercial Usage
+**
+** Licensees holding valid Qt Commercial licenses may use this file in
+** accordance with the Qt Commercial License Agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and Nokia.
+**
+** GNU Lesser General Public License Usage
+**
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 as published by the Free Software
+** 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
+** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** If you are unsure which license is appropriate for your use, please
+** contact the sales department at http://qt.nokia.com/contact.
+**
+**************************************************************************/
+
+#include "helpviewer.h"
+#include "helpconstants.h"
+#include "helpmanager.h"
+
+#include <QtCore/QCoreApplication>
+#include <QtCore/QFileInfo>
+#include <QtCore/QStringBuilder>
+#include <QtCore/QTemporaryFile>
+#include <QtCore/QUrl>
+
+#include <QtGui/QDesktopServices>
+#include <QtGui/QMouseEvent>
+
+#include <QtHelp/QHelpEngineCore>
+
+using namespace Help::Internal;
+
+QString HelpViewer::AboutBlankPage =
+    QCoreApplication::translate("HelpViewer", "<title>about:blank</title>");
+
+QString HelpViewer::PageNotFoundMessage =
+    QCoreApplication::translate("HelpViewer", "<title>Error 404...</title><div "
+    "align=\"center\"><br><br><h1>The page could not be found</h1><br><h3>'%1'"
+    "</h3></div>");
+
+bool HelpViewer::isLocalUrl(const QUrl &url)
+{
+    const QString &scheme = url.scheme();
+    return scheme.isEmpty()
+        || scheme == QLatin1String("file")
+        || scheme == QLatin1String("qrc")
+        || scheme == QLatin1String("data")
+        || scheme == QLatin1String("qthelp")
+        || scheme == QLatin1String("about");
+}
+
+bool HelpViewer::canOpenPage(const QString &url)
+{
+    return url.endsWith(QLatin1String(".html"), Qt::CaseInsensitive)
+        || url.endsWith(QLatin1String(".htm"), Qt::CaseInsensitive)
+        || url == Help::Constants::AboutBlank;
+}
+
+bool HelpViewer::launchWithExternalApp(const QUrl &url)
+{
+    if (isLocalUrl(url)) {
+        const QHelpEngineCore &helpEngine = Help::HelpManager::helpEngineCore();
+        const QUrl &resolvedUrl = helpEngine.findFile(url);
+        if (!resolvedUrl.isValid())
+            return false;
+
+        const QString& path = resolvedUrl.path();
+        if (!canOpenPage(path)) {
+            QTemporaryFile tmpTmpFile;
+            if (!tmpTmpFile.open())
+                return false;
+
+            const QString &extension = QFileInfo(path).completeSuffix();
+            QFile actualTmpFile(tmpTmpFile.fileName() % QLatin1String(".")
+                % extension);
+            if (!actualTmpFile.open(QIODevice::ReadWrite | QIODevice::Truncate))
+                return false;
+
+            actualTmpFile.write(helpEngine.fileData(resolvedUrl));
+            actualTmpFile.close();
+            return QDesktopServices::openUrl(QUrl(actualTmpFile.fileName()));
+        }
+    } else if (url.scheme() == QLatin1String("http")) {
+        return QDesktopServices::openUrl(url);
+    }
+    return false;
+}
+
+void HelpViewer::home()
+{
+    const QHelpEngineCore &engine = Help::HelpManager::helpEngineCore();
+    QString homepage = engine.customValue(QLatin1String("HomePage"),
+        QLatin1String("")).toString();
+
+    if (homepage.isEmpty()) {
+        homepage = engine.customValue(QLatin1String("DefaultHomePage"),
+            Help::Constants::AboutBlank).toString();
+    }
+
+    setSource(homepage);
+}
+
+bool HelpViewer::handleForwardBackwardMouseButtons(QMouseEvent *event)
+{
+    if (event->button() == Qt::XButton1) {
+        backward();
+        return true;
+    }
+    if (event->button() == Qt::XButton2) {
+        forward();
+        return true;
+    }
+
+    return false;
+}

src/plugins/help/helpviewer.h

+/**************************************************************************
+**
+** This file is part of Qt Creator
+**
+** Copyright (c) 2010 Nokia Corporation and/or its subsidiary(-ies).
+**
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** Commercial Usage
+**
+** Licensees holding valid Qt Commercial licenses may use this file in
+** accordance with the Qt Commercial License Agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and Nokia.
+**
+** GNU Lesser General Public License Usage
+**
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 as published by the Free Software
+** 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
+** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** If you are unsure which license is appropriate for your use, please
+** contact the sales department at http://qt.nokia.com/contact.
+**
+**************************************************************************/
+
+#ifndef HELPVIEWER_H
+#define HELPVIEWER_H
+
+#include <find/ifindsupport.h>
+
+#include <QtCore/qglobal.h>
+#include <QtCore/QString>
+#include <QtCore/QUrl>
+#include <QtCore/QVariant>
+
+#include <QtGui/QAction>
+#include <QtGui/QFont>
+
+#if defined(QT_NO_WEBKIT)
+#include <QtGui/QTextBrowser>
+#else
+#include <QtWebKit/QWebView>
+#endif
+
+namespace Help {
+    namespace Internal {
+
+#if !defined(QT_NO_WEBKIT)
+class HelpViewer : public QWebView
+#else
+class HelpViewer : public QTextBrowser
+#endif
+{
+    Q_OBJECT
+    class HelpViewerPrivate;
+    Q_DISABLE_COPY(HelpViewer)
+
+public:
+    HelpViewer(qreal zoom, QWidget *parent = 0);
+    ~HelpViewer();
+
+    QFont viewerFont() const;
+    void setViewerFont(const QFont &font);
+
+    void scaleUp();
+    void scaleDown();
+
+    void resetScale();
+    qreal scale() const;
+
+    QString title() const;
+    void setTitle(const QString &title);
+
+    QUrl source() const;
+    void setSource(const QUrl &url);
+
+    QString selectedText() const;
+    bool isForwardAvailable() const;
+    bool isBackwardAvailable() const;
+
+    bool findText(const QString &text, Find::IFindSupport::FindFlags flags,
+        bool incremental);
+
+    static QString AboutBlankPage;
+    static QString PageNotFoundMessage;
+
+    static bool isLocalUrl(const QUrl &url);
+    static bool canOpenPage(const QString &url);
+    static bool launchWithExternalApp(const QUrl &url);
+
+public slots:
+    void copy();
+    void home();
+
+    void forward();
+    void backward();
+
+signals:
+    void titleChanged();
+#if !defined(QT_NO_WEBKIT)
+    void sourceChanged(const QUrl &);
+    void forwardAvailable(bool enabled);
+    void backwardAvailable(bool enabled);
+#else
+    void loadFinished(bool finished);
+#endif
+
+protected:
+    void keyPressEvent(QKeyEvent *e);
+    void wheelEvent(QWheelEvent *event);
+    void mousePressEvent(QMouseEvent *event);
+    void mouseReleaseEvent(QMouseEvent *event);
+
+private slots:
+    void actionChanged();
+    void setLoadFinished(bool ok);
+
+private:
+    bool eventFilter(QObject *obj, QEvent *event);
+    void contextMenuEvent(QContextMenuEvent *event);
+    QVariant loadResource(int type, const QUrl &name);
+    bool handleForwardBackwardMouseButtons(QMouseEvent *e);
+
+private:
+    HelpViewerPrivate *d;
+};
+
+    }   // namespace Help
+}   // namespace Internal
+
+#endif  // HELPVIEWER_H

src/plugins/help/helpviewer_p.h

+/**************************************************************************
+**
+** This file is part of Qt Creator
+**
+** Copyright (c) 2010 Nokia Corporation and/or its subsidiary(-ies).
+**
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** Commercial Usage
+**
+** Licensees holding valid Qt Commercial licenses may use this file in
+** accordance with the Qt Commercial License Agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and Nokia.
+**
+** GNU Lesser General Public License Usage
+**
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 as published by the Free Software
+** 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
+** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** If you are unsure which license is appropriate for your use, please
+** contact the sales department at http://qt.nokia.com/contact.
+**
+**************************************************************************/
+
+#ifndef HELPVIEWERPRIVATE_H
+#define HELPVIEWERPRIVATE_H
+
+#include "centralwidget.h"
+#include "helpviewer.h"
+#include "openpagesmanager.h"
+
+#include <QtCore/QObject>
+#include <QtGui/QTextBrowser>
+
+namespace Help {
+    namespace Internal {
+
+class HelpViewer::HelpViewerPrivate : public QObject
+{
+    Q_OBJECT
+
+public:
+    HelpViewerPrivate(int zoom)
+        : zoomCount(zoom)
+        , forceFont(false)
+        , lastAnchor(QString())
+        
+    {}
+
+    bool hasAnchorAt(QTextBrowser *browser, const QPoint& pos)
+    {
+        lastAnchor = browser->anchorAt(pos);
+        if (lastAnchor.isEmpty())
+            return false;
+
+        lastAnchor = browser->source().resolved(lastAnchor).toString();
+        if (lastAnchor.at(0) == QLatin1Char('#')) {
+            QString src = browser->source().toString();
+            int hsh = src.indexOf(QLatin1Char('#'));
+            lastAnchor = (hsh >= 0 ? src.left(hsh) : src) + lastAnchor;
+        }
+        return true;
+    }
+
+    void openLink(bool newPage)
+    {
+        if(lastAnchor.isEmpty())
+            return;
+        if (newPage)
+            OpenPagesManager::instance().createPage(lastAnchor);
+        else
+            CentralWidget::instance()->setSource(lastAnchor);
+        lastAnchor.clear();
+    }
+
+public slots:
+    void openLink()
+    {
+        openLink(false);
+    }
+
+    void openLinkInNewPage()
+    {
+        openLink(true);
+    }
+
+public:
+    int zoomCount;
+    bool forceFont;
+    QString lastAnchor;
+};
+
+    }   // namespace Help
+}   // namespace Internal
+
+#endif  // HELPVIEWERPRIVATE_H

src/plugins/help/helpviewer_qtb.cpp

+/**************************************************************************
+**
+** This file is part of Qt Creator
+**
+** Copyright (c) 2010 Nokia Corporation and/or its subsidiary(-ies).
+**
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** Commercial Usage
+**
+** Licensees holding valid Qt Commercial licenses may use this file in
+** accordance with the Qt Commercial License Agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and Nokia.
+**
+** GNU Lesser General Public License Usage
+**
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 as published by the Free Software
+** 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
+** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** If you are unsure which license is appropriate for your use, please
+** contact the sales department at http://qt.nokia.com/contact.
+**
+**************************************************************************/
+
+#include "helpviewer.h"
+
+#if defined(QT_NO_WEBKIT)
+
+#include "helpconstants.h"
+#include "helpviewer_p.h"
+#include "helpmanager.h"
+
+#include <QtGui/QApplication>
+#include <QtGui/QClipboard>
+#include <QtGui/QContextMenuEvent>
+#include <QtGui/QKeyEvent>
+#include <QtGui/QMenu>
+
+#include <QtHelp/QHelpEngineCore>
+
+using namespace Find;
+using namespace Help;
+using namespace Help::Internal;
+
+// -- HelpViewer
+
+HelpViewer::HelpViewer(qreal zoom, QWidget *parent)
+    : QTextBrowser(parent)
+    , d(new HelpViewerPrivate(zoom))
+{
+    installEventFilter(this);
+    document()->setDocumentMargin(8);
+
+    QFont font = viewerFont();
+    font.setPointSize(int(font.pointSize() + zoom));
+    setViewerFont(font);
+
+    connect(this, SIGNAL(sourceChanged(QUrl)), this, SIGNAL(titleChanged()));
+    connect(this, SIGNAL(loadFinished(bool)), this, SLOT(setLoadFinished(bool)));
+}
+
+HelpViewer::~HelpViewer()
+{
+    delete d;
+}
+
+QFont HelpViewer::viewerFont() const
+{
+    const QHelpEngineCore &engine = HelpManager::helpEngineCore();
+    return qVariantValue<QFont>(engine.customValue(QLatin1String("font"),
+        qApp->font()));
+}
+
+void HelpViewer::setViewerFont(const QFont &newFont)
+{
+    if (font() != newFont) {
+        d->forceFont = true;
+        setFont(newFont);
+        d->forceFont = false;
+    }
+}
+
+void HelpViewer::scaleUp()
+{
+    if (d->zoomCount < 10) {
+        d->zoomCount++;
+        d->forceFont = true;
+        zoomIn();
+        d->forceFont = false;
+    }
+}
+
+void HelpViewer::scaleDown()
+{
+    if (d->zoomCount > -5) {
+        d->zoomCount--;
+        d->forceFont = true;
+        zoomOut();
+        d->forceFont = false;
+    }
+}
+
+void HelpViewer::resetScale()
+{
+    if (d->zoomCount != 0) {
+        d->forceFont = true;
+        zoomOut(d->zoomCount);
+        d->forceFont = false;
+    }
+    d->zoomCount = 0;
+}
+
+qreal HelpViewer::scale() const
+{
+    return d->zoomCount;
+}
+
+QString HelpViewer::title() const
+{
+    return documentTitle();
+}
+
+void HelpViewer::setTitle(const QString &title)
+{
+    setDocumentTitle(title);
+}
+
+QUrl HelpViewer::source() const
+{
+    return QTextBrowser::source();
+}
+
+void HelpViewer::setSource(const QUrl &url)
+{
+    const QString &string = url.toString();
+    if (url.isValid() && string != QLatin1String("help")) {
+        if (launchWithExternalApp(url))
+            return;
+
+        const QHelpEngineCore &engine = HelpManager::instance().helpEngineCore();
+        const QUrl &resolvedUrl = engine.findFile(url);
+        if (resolvedUrl.isValid()) {
+            QTextBrowser::setSource(resolvedUrl);
+            emit loadFinished(true);
+            return;
+        }
+    }
+
+    QTextBrowser::setSource(url);
+    setHtml(string == Help::Constants::AboutBlank ? AboutBlankPage
+        : PageNotFoundMessage.arg(url.toString()));
+    emit loadFinished(true);
+}
+
+QString HelpViewer::selectedText() const
+{
+    return textCursor().selectedText();
+}
+
+bool HelpViewer::isForwardAvailable() const
+{
+    return QTextBrowser::isForwardAvailable();
+}
+
+bool HelpViewer::isBackwardAvailable() const
+{
+    return QTextBrowser::isBackwardAvailable();
+}
+
+bool HelpViewer::findText(const QString &text, IFindSupport::FindFlags flags,
+    bool incremental)
+{
+    QTextDocument *doc = document();
+    QTextCursor cursor = textCursor();
+
+    if (!doc || cursor.isNull())
+        return false;
+
+    if (incremental)
+        cursor.setPosition(cursor.selectionStart());
+
+    QTextDocument::FindFlags f = IFindSupport::textDocumentFlagsForFindFlags(flags);
+    QTextCursor found = doc->find(text, cursor, f);
+    if (found.isNull()) {
+        if ((flags & Find::IFindSupport::FindBackward) == 0)
+            cursor.movePosition(QTextCursor::Start);
+        else
+            cursor.movePosition(QTextCursor::End);
+        found = doc->find(text, cursor, f);
+        if (found.isNull()) {
+            return false;
+        }
+    }
+    if (!found.isNull()) {
+        setTextCursor(found);
+    }
+    return true;
+}
+
+// -- public slots
+
+void HelpViewer::copy()
+{
+    QTextBrowser::copy();
+}
+
+void HelpViewer::forward()
+{
+    QTextBrowser::forward();
+}
+
+void HelpViewer::backward()
+{
+    QTextBrowser::backward();
+}
+
+// -- protected
+
+void HelpViewer::keyPressEvent(QKeyEvent *e)
+{
+    if ((e->key() == Qt::Key_Home && e->modifiers() != Qt::NoModifier)
+        || (e->key() == Qt::Key_End && e->modifiers() != Qt::NoModifier)) {
+        QKeyEvent* event = new QKeyEvent(e->type(), e->key(), Qt::NoModifier,
+            e->text(), e->isAutoRepeat(), e->count());
+        e = event;
+    }
+    QTextBrowser::keyPressEvent(e);
+}
+
+void HelpViewer::wheelEvent(QWheelEvent *e)
+{
+    if (e->modifiers() == Qt::ControlModifier) {
+        e->accept();
+        e->delta() > 0 ? scaleUp() : scaleDown();
+    } else {
+        QTextBrowser::wheelEvent(e);
+    }
+}
+
+void HelpViewer::mousePressEvent(QMouseEvent *e)
+{
+#ifdef Q_OS_LINUX
+    if (handleForwardBackwardMouseButtons(e))
+        return;
+#endif
+    QTextBrowser::mousePressEvent(e);