CppTools: Move CppHoverHandler to CppTools

This is in preparation for clang code model to provide its own hover
handler.

Change-Id: Ifbdd96f427989bd5d1fbc4badb9c38108485c2f2
Reviewed-by: Ivan Donchevskii <ivan.donchevskii@qt.io>

src/plugins/cpptools/cpphoverhandler.cpp

@@ -0,0 +1,187 @@
+/****************************************************************************
+**
+** Copyright (C) 2016 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of Qt Creator.
+**
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 3 as published by the Free Software
+** Foundation with exceptions as appearing in the file LICENSE.GPL3-EXCEPT
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-3.0.html.
+**
+****************************************************************************/
+
+#include "cpphoverhandler.h"
+
+#include "cppelementevaluator.h"
+
+#include <coreplugin/helpmanager.h>
+#include <cpptools/baseeditordocumentprocessor.h>
+#include <cpptools/cppmodelmanager.h>
+#include <cpptools/editordocumenthandle.h>
+#include <texteditor/texteditor.h>
+
+#include <utils/textutils.h>
+#include <utils/qtcassert.h>
+#include <utils/tooltip/tooltip.h>
+
+#include <QTextCursor>
+#include <QUrl>
+#include <QVBoxLayout>
+
+using namespace Core;
+using namespace TextEditor;
+
+namespace {
+
+CppTools::BaseEditorDocumentProcessor *editorDocumentProcessor(TextEditorWidget *editorWidget)
+{
+    const QString filePath = editorWidget->textDocument()->filePath().toString();
+    auto cppModelManager = CppTools::CppModelManager::instance();
+    CppTools::CppEditorDocumentHandle *editorHandle = cppModelManager->cppEditorDocument(filePath);
+
+    if (editorHandle)
+        return editorHandle->processor();
+
+    return 0;
+}
+
+bool editorDocumentProcessorHasDiagnosticAt(TextEditorWidget *editorWidget, int pos)
+{
+    if (CppTools::BaseEditorDocumentProcessor *processor = editorDocumentProcessor(editorWidget)) {
+        int line, column;
+        if (Utils::Text::convertPosition(editorWidget->document(), pos, &line, &column))
+            return processor->hasDiagnosticsAt(line, column);
+    }
+
+    return false;
+}
+
+void processWithEditorDocumentProcessor(TextEditorWidget *editorWidget,
+                                        const QPoint &point,
+                                        int position,
+                                        const QString &helpId)
+{
+    if (CppTools::BaseEditorDocumentProcessor *processor = editorDocumentProcessor(editorWidget)) {
+        int line, column;
+        if (Utils::Text::convertPosition(editorWidget->document(), position, &line, &column)) {
+            auto layout = new QVBoxLayout;
+            layout->setContentsMargins(0, 0, 0, 0);
+            layout->setSpacing(2);
+            processor->addDiagnosticToolTipToLayout(line, column, layout);
+            Utils::ToolTip::show(point, layout, editorWidget, helpId);
+        }
+    }
+}
+
+} // anonymous namespace
+
+namespace CppTools {
+
+void CppHoverHandler::identifyMatch(TextEditorWidget *editorWidget, int pos)
+{
+    m_positionForEditorDocumentProcessor = -1;
+
+    if (editorDocumentProcessorHasDiagnosticAt(editorWidget, pos)) {
+        setPriority(Priority_Diagnostic);
+        m_positionForEditorDocumentProcessor = pos;
+        return;
+    }
+
+    QTextCursor tc(editorWidget->document());
+    tc.setPosition(pos);
+
+    CppElementEvaluator evaluator(editorWidget);
+    evaluator.setTextCursor(tc);
+    evaluator.execute();
+    if (evaluator.hasDiagnosis()) {
+        setToolTip(evaluator.diagnosis());
+        setPriority(Priority_Diagnostic);
+    } else if (evaluator.identifiedCppElement()) {
+        const QSharedPointer<CppElement> &cppElement = evaluator.cppElement();
+        if (priority() != Priority_Diagnostic) {
+            setToolTip(cppElement->tooltip);
+            setPriority(cppElement->tooltip.isEmpty() ? Priority_None : Priority_Tooltip);
+        }
+        QStringList candidates = cppElement->helpIdCandidates;
+        candidates.removeDuplicates();
+        foreach (const QString &helpId, candidates) {
+            if (helpId.isEmpty())
+                continue;
+
+            const QMap<QString, QUrl> helpLinks = HelpManager::linksForIdentifier(helpId);
+            if (!helpLinks.isEmpty()) {
+                setLastHelpItemIdentified(HelpItem(helpId,
+                                                   cppElement->helpMark,
+                                                   cppElement->helpCategory,
+                                                   helpLinks));
+                break;
+            }
+        }
+    }
+}
+
+void CppHoverHandler::decorateToolTip()
+{
+    if (m_positionForEditorDocumentProcessor != -1)
+        return;
+
+    if (Qt::mightBeRichText(toolTip()))
+        setToolTip(toolTip().toHtmlEscaped());
+
+    if (priority() != Priority_Diagnostic)
+        return;
+
+    const HelpItem &help = lastHelpItemIdentified();
+    if (help.isValid()) {
+        // If Qt is built with a namespace, we still show the tip without it, as
+        // it is in the docs and for consistency with the doc extraction mechanism.
+        const HelpItem::Category category = help.category();
+        const QString &contents = help.extractContent(false);
+        if (!contents.isEmpty()) {
+            if (category == HelpItem::ClassOrNamespace)
+                setToolTip(help.helpId() + contents);
+            else
+                setToolTip(contents);
+        } else if (category == HelpItem::Typedef ||
+                   category == HelpItem::Enum ||
+                   category == HelpItem::ClassOrNamespace) {
+            // This approach is a bit limited since it cannot be used for functions
+            // because the help id doesn't really help in that case.
+            QString prefix;
+            if (category == HelpItem::Typedef)
+                prefix = QLatin1String("typedef ");
+            else if (category == HelpItem::Enum)
+                prefix = QLatin1String("enum ");
+            setToolTip(prefix + help.helpId());
+        }
+    }
+}
+
+void CppHoverHandler::operateTooltip(TextEditor::TextEditorWidget *editorWidget,
+                                     const QPoint &point)
+{
+    if (m_positionForEditorDocumentProcessor == -1) {
+        BaseHoverHandler::operateTooltip(editorWidget, point);
+        return;
+    }
+
+    const HelpItem helpItem = lastHelpItemIdentified();
+    const QString helpId = helpItem.isValid() ? helpItem.helpId() : QString();
+    processWithEditorDocumentProcessor(editorWidget, point, m_positionForEditorDocumentProcessor,
+                                       helpId);
+}
+
+} // namespace CppTools