Move help manager into core.

 - lessens open file handles
 - improves help plugin startup further

Task-number: QTCREATORBUG-337
Reviewed-by: ck

1 files changed, 321 insertions, 0 deletions

diff --git a/src/plugins/coreplugin/helpmanager.cpp b/src/plugins/coreplugin/helpmanager.cpp
new file mode 100644
index 0000000000..85cf89a1a5
--- /dev/null
+++ b/src/plugins/coreplugin/helpmanager.cpp
@@ -0,0 +1,321 @@
+/**************************************************************************
+**
+** 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 "helpmanager.h"
+
+#include "icore.h"
+
+#include <QtCore/QDebug>
+#include <QtCore/QDir>
+#include <QtCore/QFileInfo>
+#include <QtCore/QStringList>
+
+#include <QtHelp/QHelpEngineCore>
+
+#include <QtSql/QSqlDatabase>
+#include <QtSql/QSqlDriver>
+#include <QtSql/QSqlError>
+#include <QtSql/QSqlQuery>
+
+namespace Core {
+
+HelpManager *HelpManager::m_instance = 0;
+
+static const char linksForKeyQuery[] = "SELECT d.Title, f.Name, e.Name, "
+    "d.Name, a.Anchor FROM IndexTable a, FileNameTable d, FolderTable e, "
+    "NamespaceTable f WHERE a.FileId=d.FileId AND d.FolderId=e.Id AND "
+    "a.NamespaceId=f.Id AND a.Name='%1'";
+
+// -- DbCleaner
+
+struct DbCleaner {
+    DbCleaner(const QString &dbName)
+        : name(dbName) {}
+    ~DbCleaner() {
+        QSqlDatabase::removeDatabase(name);
+    }
+    QString name;
+};
+
+// -- HelpManager
+
+HelpManager::HelpManager(QObject *parent)
+    : QObject(parent)
+    , m_needsSetup(true)
+    , m_helpEngine(0)
+{
+    Q_ASSERT(!m_instance);
+    m_instance = this;
+
+    connect(Core::ICore::instance(), SIGNAL(coreOpened()), this,
+        SLOT(setupHelpManager()));
+}
+
+HelpManager::~HelpManager()
+{
+    delete m_helpEngine;
+    m_helpEngine = 0;
+
+    m_instance = 0;
+}
+
+HelpManager* HelpManager::instance()
+{
+    Q_ASSERT(m_instance);
+    return m_instance;
+}
+
+QString HelpManager::collectionFilePath()
+{
+    const QFileInfo fi(Core::ICore::instance()->settings()->fileName());
+    const QDir directory(fi.absolutePath() + QLatin1String("/qtcreator"));
+    if (!directory.exists())
+        directory.mkpath(directory.absolutePath());
+    return QDir::cleanPath(directory.absolutePath() + QLatin1String("/helpcollection.qhc"));
+}
+
+void HelpManager::registerDocumentation(const QStringList &files)
+{
+    if (m_needsSetup) {
+        m_filesToRegister.append(files);
+        return;
+    }
+
+    bool docsChanged = false;
+    foreach (const QString &file, files) {
+        const QString &nameSpace = m_helpEngine->namespaceName(file);
+        if (nameSpace.isEmpty())
+            continue;
+        if (!m_helpEngine->registeredDocumentations().contains(nameSpace)) {
+            if (m_helpEngine->registerDocumentation(file)) {
+                docsChanged = true;
+            } else {
+                qWarning() << "Error registering namespace '" << nameSpace
+                    << "' from file '" << file << "':" << m_helpEngine->error();
+            }
+        }
+    }
+    if (docsChanged)
+        emit documentationChanged();
+}
+
+void HelpManager::unregisterDocumentation(const QStringList &nameSpaces)
+{
+    if (m_needsSetup) {
+        m_nameSpacesToUnregister.append(nameSpaces);
+        return;
+    }
+
+    bool docsChanged = false;
+    foreach (const QString &nameSpace, nameSpaces) {
+        if (m_helpEngine->unregisterDocumentation(nameSpace)) {
+            docsChanged = true;
+        } else {
+            qWarning() << "Error unregistering namespace '" << nameSpace
+                << "' from file '" << m_helpEngine->documentationFileName(nameSpace)
+                << "': " << m_helpEngine->error();
+        }
+    }
+    if (docsChanged)
+        emit documentationChanged();
+}
+
+QUrl buildQUrl(const QString &nameSpace, const QString &folder,
+    const QString &relFileName, const QString &anchor)
+{
+    QUrl url;
+    url.setScheme(QLatin1String("qthelp"));
+    url.setAuthority(nameSpace);
+    url.setPath(folder + QLatin1Char('/') + relFileName);
+    url.setFragment(anchor);
+    return url;
+}
+
+// This should go into Qt 4.8 once we start using it for Qt Creator
+QMap<QString, QUrl> HelpManager::linksForKeyword(const QString &key) const
+{
+    QMap<QString, QUrl> links;
+    if (m_needsSetup)
+        return links;
+
+    const QLatin1String sqlite("QSQLITE");
+    const QLatin1String name("HelpManager::linksForKeyword");
+
+    DbCleaner cleaner(name);
+    QSqlDatabase db = QSqlDatabase::addDatabase(sqlite, name);
+    if (db.driver() && db.driver()->lastError().type() == QSqlError::NoError) {
+        const QStringList &registeredDocs = m_helpEngine->registeredDocumentations();
+        foreach (const QString &nameSpace, registeredDocs) {
+            db.setDatabaseName(m_helpEngine->documentationFileName(nameSpace));
+            if (db.open()) {
+                QSqlQuery query = QSqlQuery(db);
+                query.setForwardOnly(true);
+                query.exec(QString::fromLatin1(linksForKeyQuery).arg(key));
+                while (query.next()) {
+                    QString title = query.value(0).toString();
+                    if (title.isEmpty()) // generate a title + corresponding path
+                        title = key + QLatin1String(" : ") + query.value(3).toString();
+                    links.insertMulti(title, buildQUrl(query.value(1).toString(),
+                        query.value(2).toString(), query.value(3).toString(),
+                        query.value(4).toString()));
+                }
+            }
+        }
+    }
+    return links;
+}
+
+QMap<QString, QUrl> HelpManager::linksForIdentifier(const QString &id) const
+{
+    if (m_needsSetup)
+        return QMap<QString, QUrl>();
+    return m_helpEngine->linksForIdentifier(id);
+}
+
+// This should go into Qt 4.8 once we start using it for Qt Creator
+QStringList HelpManager::findKeywords(const QString &key, int maxHits) const
+{
+    QStringList keywords;
+    if (m_needsSetup)
+        return keywords;
+
+    const QLatin1String sqlite("QSQLITE");
+    const QLatin1String name("HelpManager::findKeywords");
+
+    DbCleaner cleaner(name);
+    QSqlDatabase db = QSqlDatabase::addDatabase(sqlite, name);
+    if (db.driver() && db.driver()->lastError().type() == QSqlError::NoError) {
+        const QStringList &registeredDocs = m_helpEngine->registeredDocumentations();
+        foreach (const QString &nameSpace, registeredDocs) {
+            db.setDatabaseName(m_helpEngine->documentationFileName(nameSpace));
+            if (db.open()) {
+                QSqlQuery query = QSqlQuery(db);
+                query.setForwardOnly(true);
+                query.exec(QString::fromLatin1("SELECT DISTINCT Name FROM "
+                    "IndexTable WHERE Name LIKE '%%1%'").arg(key));
+                while (query.next()) {
+                    const QString &key = query.value(0).toString();
+                    if (!key.isEmpty()) {
+                        keywords.append(key);
+                        if (keywords.count() == maxHits)
+                            return keywords;
+                    }
+                }
+            }
+        }
+    }
+    return keywords;
+}
+
+QUrl HelpManager::findFile(const QUrl &url) const
+{
+    if (m_needsSetup)
+        return QUrl();
+    return m_helpEngine->findFile(url);
+}
+
+void HelpManager::handleHelpRequest(const QString &url)
+{
+    emit helpRequested(QUrl(url));
+}
+
+QStringList HelpManager::registeredNamespaces() const
+{
+    if (m_needsSetup)
+        return QStringList();
+    return m_helpEngine->registeredDocumentations();
+}
+
+QString HelpManager::namespaceFromFile(const QString &file) const
+{
+    if (m_needsSetup)
+        return QString();
+    return m_helpEngine->namespaceName(file);
+}
+
+QString HelpManager::fileFromNamespace(const QString &nameSpace) const
+{
+    if (m_needsSetup)
+        return QString();
+    return m_helpEngine->documentationFileName(nameSpace);
+}
+
+// -- private slots
+
+void HelpManager::setupHelpManager()
+{
+    if (!m_needsSetup)
+        return;
+    m_needsSetup = false;
+
+    m_helpEngine = new QHelpEngineCore(collectionFilePath(), this);
+    m_helpEngine->setAutoSaveFilter(false);
+    m_helpEngine->setCurrentFilter(tr("Unfiltered"));
+    m_helpEngine->setupData();
+
+    verifyDocumenation();
+
+    if (!m_nameSpacesToUnregister.isEmpty()) {
+        unregisterDocumentation(m_nameSpacesToUnregister);
+        m_nameSpacesToUnregister.clear();
+    }
+
+    // this might come from the installer
+    const QLatin1String key("AddedDocs");
+    const QString &addedDocs = m_helpEngine->customValue(key).toString();
+    if (!addedDocs.isEmpty()) {
+        m_helpEngine->removeCustomValue(key);
+        m_filesToRegister += addedDocs.split(QLatin1Char(';'));
+    }
+
+    if (!m_filesToRegister.isEmpty()) {
+        registerDocumentation(m_filesToRegister);
+        m_filesToRegister.clear();
+    }
+
+    emit setupFinished();
+}
+
+// -- private
+
+void HelpManager::verifyDocumenation()
+{
+    QStringList nameSpacesToUnregister;
+    const QStringList &registeredDocs = m_helpEngine->registeredDocumentations();
+    foreach (const QString &nameSpace, registeredDocs) {
+        const QString &file = m_helpEngine->documentationFileName(nameSpace);
+        if (!QFileInfo(file).exists())
+            nameSpacesToUnregister.append(nameSpace);
+    }
+
+    if (!nameSpacesToUnregister.isEmpty())
+        unregisterDocumentation(nameSpacesToUnregister);
+}
+
+}   // Core