C++ Detach the CppEditor from code-model internals.

- Moved document update handling into CppTools.
- Moved semantic info calculation into CppTools.
- Moved semantic highlighting into CppTools.

Change-Id: I253861bf074a64b1f657f7a4a8e6583871b5285f
Reviewed-by: Nikolai Kosjar <nikolai.kosjar@digia.com>

src/plugins/cpptools/cpptoolseditorsupport.h

@@ -30,63 +30,154 @@
 #ifndef CPPTOOLSEDITORSUPPORT_H
 #define CPPTOOLSEDITORSUPPORT_H
 
+#include "cpphighlightingsupport.h"
+#include "cppmodelmanager.h"
+#include "cppsemanticinfo.h"
+
+#include <cplusplus/CppDocument.h>
+
+#include <QFuture>
 #include <QObject>
 #include <QPointer>
-#include <QFuture>
-
-QT_BEGIN_NAMESPACE
-class QTimer;
-QT_END_NAMESPACE
+#include <QTimer>
 
 namespace CPlusPlus { class AST; }
 
 namespace TextEditor {
-class ITextEditor;
+class BaseTextEditor;
 class ITextMark;
 } // namespace TextEditor
 
 namespace CppTools {
-namespace Internal {
 
-class CppModelManager;
-
-class CppEditorSupport: public QObject
+/**
+ * \brief The CppEditorSupport class oversees the actions that happen when a C++ text editor updates
+ *        its document.
+ *
+ * The following steps are taken:
+ * 1. the text editor fires a contentsChanged() signal that triggers updateDocument
+ * 2. update document will start a timer, or reset the timer if it was already running. This way
+ *    subsequent updates (e.g. keypresses) get bunched together instead of running the subsequent
+ *    actions for every key press
+ * 3. when the timer from step 2 fires, updateDocumentNow() is triggered. That tells the
+ *    model-manager to update the CPlusPlus::Document by re-indexing it.
+ * 4. when the model-manager finishes, it fires a documentUpdated(CPlusPlus::Document::Ptr) signal,
+ *    that is connected to onDocumentUpdated(CPlusPlus::Document::Ptr), which does 4 things:
+ *    a) updates the ifdeffed-out blocks in the EditorUpdate
+ *    b) calls setExtraDiagnostics with the diagnostics from the parser, which in turn calls
+ *       onDiagnosticsChanged on the UI thread, and that schedules an editor update timer. When this
+ *       timer fires, updateEditorNow() is called, which will apply the updates to the editor.
+ *    c) a semantic-info recalculation is started in a future
+ *    d) the documentUpdated() signal is emitted, which can be used by a widget to do things
+ * 5. semantic-info calculation from 4c is done by a future that calls recalculateSemanticInfoNow(),
+ *    which emits semanticInfoUpdated() when it is finished. Editors can also listen in on this
+ *    signal to do things like highlighting the local usages.
+ * 6. the semanticInfoUpdated() is connected to the startHighlighting() slot, which will start
+ *    another future for doing the semantic highlighting. The highlighterStarted signal is emitted,
+ *    with the highlighting future as a parameter, so editors can hook it up to a QFutureWatcher
+ *    and get notifications.
+ *
+ * Both the semantic info calculation and the highlighting calculation will cancel an already running
+ * future. They will also check that the result of a previous step is not already outdated, meaning
+ * that they check the revision of the editor document to see if a user changed the document while
+ * the calculation was running.
+ */
+class CPPTOOLS_EXPORT CppEditorSupport: public QObject
 {
     Q_OBJECT
 
 public:
-    CppEditorSupport(CppModelManager *modelManager);
+    CppEditorSupport(Internal::CppModelManager *modelManager, TextEditor::BaseTextEditor *textEditor);
     virtual ~CppEditorSupport();
 
-    TextEditor::ITextEditor *textEditor() const;
-    void setTextEditor(TextEditor::ITextEditor *textEditor);
+    QString fileName() const;
 
-    int updateDocumentInterval() const;
-    void setUpdateDocumentInterval(int updateDocumentInterval);
-
-    QString contents();
+    QString contents() const;
     unsigned editorRevision() const;
 
-Q_SIGNALS:
-    void contentsChanged();
+    void setExtraDiagnostics(const QString &key,
+                             const QList<CPlusPlus::Document::DiagnosticMessage> &messages);
 
-private Q_SLOTS:
+    /// Retrieve the semantic info, which will get recalculated on the current
+    /// thread if it is outdate.
+    SemanticInfo recalculateSemanticInfo(bool emitSignalWhenFinished = true);
+
+    /// Recalculates the semantic info in a future, and will emit the semanticInfoUpdated() signal
+    /// when finished.
+    /// \param force do not check if the old semantic info is still valid
+    void recalculateSemanticInfoDetached(bool force = false);
+
+signals:
+    void documentUpdated();
+    void diagnosticsChanged();
+    void semanticInfoUpdated(CppTools::SemanticInfo);
+    void highlighterStarted(QFuture<TextEditor::HighlightingResult>, unsigned revision);
+
+private slots:
     void updateDocument();
     void updateDocumentNow();
 
-private:
-    enum { UPDATE_DOCUMENT_DEFAULT_INTERVAL = 150 };
+    void onDocumentUpdated(CPlusPlus::Document::Ptr doc);
+    void startHighlighting();
 
-    CppModelManager *_modelManager;
-    QPointer<TextEditor::ITextEditor> _textEditor;
-    QTimer *_updateDocumentTimer;
-    int _updateDocumentInterval;
-    unsigned _revision;
-    QFuture<void> _documentParser;
-    QString _cachedContents;
+    void onDiagnosticsChanged();
+
+    void updateEditor();
+    void updateEditorNow();
+
+private:
+    typedef TextEditor::BaseTextEditorWidget::BlockRange BlockRange;
+    struct EditorUpdates {
+        EditorUpdates()
+            : revision(-1)
+        {}
+        int revision;
+        QList<QTextEdit::ExtraSelection> selections;
+        QList<BlockRange> ifdefedOutBlocks;
+    };
+
+    enum {
+        UpdateDocumentDefaultInterval = 150,
+        UpdateEditorInterval = 300
+    };
+
+private:
+    SemanticInfo::Source currentSource(bool force);
+    void recalculateSemanticInfoNow(const SemanticInfo::Source &source, bool emitSignalWhenFinished,
+                                    CPlusPlus::TopLevelDeclarationProcessor *processor = 0);
+    void recalculateSemanticInfoDetached_helper(QFutureInterface<void> &future,
+                                                SemanticInfo::Source source);
+
+private:
+    Internal::CppModelManager *m_modelManager;
+    QPointer<TextEditor::BaseTextEditor> m_textEditor;
+    QTimer *m_updateDocumentTimer;
+    int m_updateDocumentInterval;
+    unsigned m_revision;
+    QFuture<void> m_documentParser;
+
+    // content caching
+    mutable QString m_cachedContents;
+    mutable int m_cachedContentsEditorRevision;
+
+    QTimer *m_updateEditorTimer;
+    EditorUpdates m_editorUpdates;
+
+    QMutex m_diagnosticsMutex;
+    QHash<QString, QList<CPlusPlus::Document::DiagnosticMessage> > m_allDiagnostics;
+
+    // Semantic info:
+    bool m_initialized;
+    mutable QMutex m_lastSemanticInfoLock;
+    SemanticInfo m_lastSemanticInfo;
+    QFuture<void> m_futureSemanticInfo;
+
+    // Highlighting:
+    unsigned m_lastHighlightRevision;
+    QFuture<TextEditor::HighlightingResult> m_highlighter;
+    QScopedPointer<CppTools::CppHighlightingSupport> m_highlightingSupport;
 };
 
-} // namespace Internal
 } // namespace CppTools
 
 #endif // CPPTOOLSEDITORSUPPORT_H