/***************************************************************************
**
** This file is part of Qt Creator
**
** Copyright (c) 2008 Nokia Corporation and/or its subsidiary(-ies).
**
** Contact:  Qt Software Information (qt-info@nokia.com)
**
**
** Non-Open Source Usage
**
** Licensees may use this file in accordance with the Qt Beta Version
** License Agreement, Agreement version 2.2 provided with the Software or,
** alternatively, in accordance with the terms contained in a written
** agreement between you and Nokia.
**
** GNU General Public License Usage
**
** Alternatively, this file may be used under the terms of the GNU General
** Public License versions 2.0 or 3.0 as published by the Free Software
** Foundation and appearing in the file LICENSE.GPL included in the packaging
** of this file.  Please review the following information to ensure GNU
** General Public Licensing requirements will be met:
**
** http://www.fsf.org/licensing/licenses/info/GPLv2.html and
** http://www.gnu.org/copyleft/gpl.html.
**
** In addition, as a special exception, Nokia gives you certain additional
** rights. These rights are described in the Nokia Qt GPL Exception
** version 1.2, included in the file GPL_EXCEPTION.txt in this package.
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***************************************************************************/

#define _SCL_SECURE_NO_WARNINGS 1
#include "pp.h"

#include "cppmodelmanager.h"
#include "cpphoverhandler.h"
#include "cpptoolsconstants.h"
#include "cpptoolseditorsupport.h"

#include <qtconcurrent/runextensions.h>
#include <texteditor/itexteditor.h>
#include <texteditor/basetexteditor.h>

#include <projectexplorer/project.h>
#include <projectexplorer/projectexplorer.h>
#include <projectexplorer/projectexplorerconstants.h>
#include <projectexplorer/session.h>

#include <coreplugin/icore.h>
#include <coreplugin/uniqueidmanager.h>
#include <coreplugin/editormanager/editormanager.h>
#include <coreplugin/progressmanager/progressmanager.h>

#include <TranslationUnit.h>
#include <Semantic.h>
#include <AST.h>
#include <Scope.h>
#include <Literals.h>
#include <Symbols.h>
#include <Names.h>
#include <NameVisitor.h>
#include <TypeVisitor.h>
#include <Lexer.h>
#include <Token.h>

#include <QPlainTextEdit>
#include <QTime>
#include <QDebug>

using namespace CPlusPlus;

namespace CppTools {
namespace Internal {

static const char pp_configuration_file[] = "<configuration>";

static const char pp_configuration[] =
    "# 1 \"<configuration>\"\n"
    "#define __GNUC_MINOR__ 0\n"
    "#define __GNUC__ 4\n"
    "#define __GNUG__ 4\n"
    "#define __STDC_HOSTED__ 1\n"
    "#define __VERSION__ \"4.0.1 (fake)\"\n"
    "#define __cplusplus 1\n"

    "#define __extension__\n"
    "#define __context__\n"
    "#define __range__\n"
    "#define __asm(a...)\n"
    "#define __asm__(a...)\n"
    "#define   restrict\n"
    "#define __restrict\n"

    // ### add macros for win32
    "#define __cdecl\n"
    "#define QT_WA(x) x\n"
    "#define API\n"
    "#define WINAPI\n"
    "#define CALLBACK\n"
    "#define STDMETHODCALLTYPE\n"
    "#define __RPC_FAR\n"
    "#define APIENTRY\n"
    "#define __declspec(a)\n"
    "#define STDMETHOD(method) virtual HRESULT STDMETHODCALLTYPE method\n";

class CppPreprocessor: public rpp::Client
{
public:
    CppPreprocessor(QPointer<CppModelManager> modelManager)
        : m_modelManager(modelManager),
          m_documents(modelManager->documents()),
          m_proc(this, env)
    { }

    void setWorkingCopy(const QMap<QString, QByteArray> &workingCopy)
    { m_workingCopy = workingCopy; }

    void setIncludePaths(const QStringList &includePaths)
    { m_includePaths = includePaths; }

    void setFrameworkPaths(const QStringList &frameworkPaths)
    { m_frameworkPaths = frameworkPaths; }

    void addIncludePath(const QString &path)
    { m_includePaths.append(path); }

    void setProjectFiles(const QStringList &files)
    { m_projectFiles = files; }

    void operator()(QString &fileName)
    { sourceNeeded(fileName, IncludeGlobal); }

protected:
    bool includeFile(const QString &absoluteFilePath, QByteArray *result)
    {
        if (absoluteFilePath.isEmpty() || m_included.contains(absoluteFilePath)) {
            return true;
        }

        if (m_workingCopy.contains(absoluteFilePath)) {
            m_included.insert(absoluteFilePath);
            *result = m_workingCopy.value(absoluteFilePath);
            return true;
        }

        QFileInfo fileInfo(absoluteFilePath);
        if (! fileInfo.isFile())
            return false;

        QFile file(absoluteFilePath);
        if (file.open(QFile::ReadOnly)) {
            m_included.insert(absoluteFilePath);
            QTextStream stream(&file);
            const QString contents = stream.readAll();
            *result = contents.toUtf8();
            file.close();
            return true;
        }

        return false;
    }

    QByteArray tryIncludeFile(QString &fileName, IncludeType type)
    {
        QFileInfo fileInfo(fileName);
        if (fileName == QLatin1String(pp_configuration_file) || fileInfo.isAbsolute()) {
            QByteArray contents;
            includeFile(fileName, &contents);
            return contents;
        }

        if (type == IncludeLocal && m_currentDoc) {
            QFileInfo currentFileInfo(m_currentDoc->fileName());
            QString path = currentFileInfo.absolutePath();
            path += QLatin1Char('/');
            path += fileName;
            path = QDir::cleanPath(path);
            QByteArray contents;
            if (includeFile(path, &contents)) {
                fileName = path;
                return contents;
            }
        }

        foreach (const QString &includePath, m_includePaths) {
            QString path = includePath;
            path += QLatin1Char('/');
            path += fileName;
            path = QDir::cleanPath(path);
            QByteArray contents;
            if (includeFile(path, &contents)) {
                fileName = path;
                return contents;
            }
        }

        // look in the system include paths
        foreach (const QString &includePath, m_systemIncludePaths) {
            QString path = includePath;
            path += QLatin1Char('/');
            path += fileName;
            path = QDir::cleanPath(path);
            QByteArray contents;
            if (includeFile(path, &contents)) {
                fileName = path;
                return contents;
            }
        }

        int index = fileName.indexOf(QLatin1Char('/'));
        if (index != -1) {
            QString frameworkName = fileName.left(index);
            QString name = fileName.mid(index + 1);

            foreach (const QString &frameworkPath, m_frameworkPaths) {
                QString path = frameworkPath;
                path += QLatin1Char('/');
                path += frameworkName;
                path += QLatin1String(".framework/Headers/");
                path += name;
                QByteArray contents;
                if (includeFile(path, &contents)) {
                    fileName = path;
                    return contents;
                }
            }
        }

        QString path = fileName;
        if (path.at(0) != QLatin1Char('/'))
            path.prepend(QLatin1Char('/'));

        foreach (const QString &projectFile, m_projectFiles) {
            if (projectFile.endsWith(path)) {
                fileName = projectFile;
                QByteArray contents;
                includeFile(fileName, &contents);
                return contents;
            }
        }

        //qDebug() << "**** file" << fileName << "not found!";
        return QByteArray();
    }

    virtual void macroAdded(const QByteArray &macroName, const QByteArray &macroText)
    {
        if (! m_currentDoc)
            return;

        m_currentDoc->appendMacro(macroName, macroText);
    }

    void mergeEnvironment(Document::Ptr doc)
    {
        QSet<QString> processed;
        mergeEnvironment(doc, &processed);
    }

    void mergeEnvironment(Document::Ptr doc, QSet<QString> *processed)
    {
        if (! doc)
            return;

        const QString fn = doc->fileName();

        if (processed->contains(fn))
            return;

        processed->insert(fn);

        foreach (QString includedFile, doc->includedFiles())
            mergeEnvironment(m_documents.value(includedFile), processed);

        const QByteArray macros = doc->definedMacros();
        QByteArray localFileName = doc->fileName().toUtf8();

        QByteArray dummy;
        m_proc(localFileName, macros, &dummy);
    }

    virtual void startSkippingBlocks(unsigned offset)
    {
        //qDebug() << "start skipping blocks:" << offset;
        if (m_currentDoc)
            m_currentDoc->startSkippingBlocks(offset);
    }

    virtual void stopSkippingBlocks(unsigned offset)
    {
        //qDebug() << "stop skipping blocks:" << offset;
        if (m_currentDoc)
            m_currentDoc->stopSkippingBlocks(offset);
    }

    virtual void sourceNeeded(QString &fileName, IncludeType type)
    {
        if (fileName.isEmpty())
            return;

        QByteArray contents = tryIncludeFile(fileName, type);

        if (m_currentDoc) {
            m_currentDoc->addIncludeFile(fileName);
            if (contents.isEmpty() && ! QFileInfo(fileName).isAbsolute()) {
                QString msg;
                msg += fileName;
                msg += QLatin1String(": No such file or directory");
                Document::DiagnosticMessage d(Document::DiagnosticMessage::Warning,
                                              m_currentDoc->fileName(),
                                              env.currentLine, /*column = */ 0,
                                              msg);
                m_currentDoc->addDiagnosticMessage(d);
                //qWarning() << "file not found:" << fileName << m_currentDoc->fileName() << env.current_line;
            }
        }

        if (! contents.isEmpty()) {
            Document::Ptr cachedDoc = m_documents.value(fileName);
            if (cachedDoc && m_currentDoc) {
                mergeEnvironment(cachedDoc);
            } else {
                Document::Ptr previousDoc = switchDocument(Document::create(fileName));

                const QByteArray previousFile = env.current_file;
                const unsigned previousLine = env.currentLine;

                env.current_file = QByteArray(m_currentDoc->translationUnit()->fileName(),
                                              m_currentDoc->translationUnit()->fileNameLength());

                QByteArray preprocessedCode;
                m_proc(contents, &preprocessedCode);
                //qDebug() << preprocessedCode;

                env.current_file = previousFile;
                env.currentLine = previousLine;

                m_currentDoc->setSource(preprocessedCode);
                m_currentDoc->parse();
                m_currentDoc->check();
                m_currentDoc->releaseTranslationUnit(); // release the AST and the token stream.

                if (m_modelManager)
                    m_modelManager->emitDocumentUpdated(m_currentDoc);
                (void) switchDocument(previousDoc);
            }
        }
    }

    Document::Ptr switchDocument(Document::Ptr doc)
    {
        Document::Ptr previousDoc = m_currentDoc;
        m_currentDoc = doc;
        return previousDoc;
    }

private:
    QPointer<CppModelManager> m_modelManager;
    CppModelManager::DocumentTable m_documents;
    rpp::Environment env;
    rpp::pp m_proc;
    QStringList m_includePaths;
    QStringList m_systemIncludePaths;
    QMap<QString, QByteArray> m_workingCopy;
    QStringList m_projectFiles;
    QStringList m_frameworkPaths;
    QSet<QString> m_included;
    Document::Ptr m_currentDoc;
};

} // namespace Internal
} // namespace CppTools


using namespace CppTools;
using namespace CppTools::Internal;

/*!
    \class CppTools::CppModelManager
    \brief The CppModelManager keeps track of one CppCodeModel instance
           for each project and all related CppCodeModelPart instances.

    It also takes care of updating the code models when C++ files are
    modified within Workbench.
*/

CppModelManager::CppModelManager(QObject *parent) :
    CppModelManagerInterface(parent),
    m_core(ExtensionSystem::PluginManager::instance()->getObject<Core::ICore>())
{
    m_projectExplorer = ExtensionSystem::PluginManager::instance()
                        ->getObject<ProjectExplorer::ProjectExplorerPlugin>();

    Q_ASSERT(m_projectExplorer);

    ProjectExplorer::SessionManager *session = m_projectExplorer->session();
    Q_ASSERT(session != 0);

    connect(session, SIGNAL(aboutToRemoveProject(ProjectExplorer::Project *)),
            this, SLOT(onAboutToRemoveProject(ProjectExplorer::Project *)));

    connect(session, SIGNAL(sessionUnloaded()),
            this, SLOT(onSessionUnloaded()));

    qRegisterMetaType<CPlusPlus::Document::Ptr>("CPlusPlus::Document::Ptr");

    // thread connections
    connect(this, SIGNAL(documentUpdated(CPlusPlus::Document::Ptr)),
            this, SLOT(onDocumentUpdated(CPlusPlus::Document::Ptr)));

    m_hoverHandler = new CppHoverHandler(this, this);

    // Listen for editor closed and opened events so that we can keep track of changing files
    connect(m_core->editorManager(), SIGNAL(editorOpened(Core::IEditor *)),
        this, SLOT(editorOpened(Core::IEditor *)));

    connect(m_core->editorManager(), SIGNAL(editorAboutToClose(Core::IEditor *)),
        this, SLOT(editorAboutToClose(Core::IEditor *)));
}

CppModelManager::~CppModelManager()
{ }

Document::Ptr CppModelManager::document(const QString &fileName)
{ return m_documents.value(fileName); }

CppModelManager::DocumentTable CppModelManager::documents()
{ return m_documents; }

QStringList CppModelManager::projectFiles() const
{
    QStringList files;
    QMapIterator<ProjectExplorer::Project *, ProjectInfo> it(m_projects);
    while (it.hasNext()) {
        it.next();
        ProjectInfo pinfo = it.value();
        files += pinfo.sourceFiles;
    }
    return files;
}

QStringList CppModelManager::includePaths() const
{
    QStringList includePaths;
    QMapIterator<ProjectExplorer::Project *, ProjectInfo> it(m_projects);
    while (it.hasNext()) {
        it.next();
        ProjectInfo pinfo = it.value();
        includePaths += pinfo.includePaths;
    }
    return includePaths;
}

QStringList CppModelManager::frameworkPaths() const
{
    QStringList frameworkPaths;
    QMapIterator<ProjectExplorer::Project *, ProjectInfo> it(m_projects);
    while (it.hasNext()) {
        it.next();
        ProjectInfo pinfo = it.value();
        frameworkPaths += pinfo.frameworkPaths;
    }
    return frameworkPaths;
}

QByteArray CppModelManager::definedMacros() const
{
    QByteArray macros;
    QMapIterator<ProjectExplorer::Project *, ProjectInfo> it(m_projects);
    while (it.hasNext()) {
        it.next();
        ProjectInfo pinfo = it.value();
        macros += pinfo.defines;
    }
    return macros;
}

QMap<QString, QByteArray> CppModelManager::buildWorkingCopyList() const
{
    QMap<QString, QByteArray> workingCopy;
    QMapIterator<TextEditor::ITextEditor *, CppEditorSupport *> it(m_editorSupport);
    while (it.hasNext()) {
        it.next();
        TextEditor::ITextEditor *textEditor = it.key();
        CppEditorSupport *editorSupport = it.value();
        QString fileName = textEditor->file()->fileName();
        workingCopy[fileName] = editorSupport->contents().toUtf8();
    }

    // add the project configuration file
    QByteArray conf(pp_configuration);
    conf += definedMacros();
    workingCopy[pp_configuration_file] = conf;

    return workingCopy;
}

void CppModelManager::updateSourceFiles(const QStringList &sourceFiles)
{ (void) refreshSourceFiles(sourceFiles); }

CppModelManager::ProjectInfo *CppModelManager::projectInfo(ProjectExplorer::Project *project)
{ return &m_projects[project]; }

QFuture<void> CppModelManager::refreshSourceFiles(const QStringList &sourceFiles)
{
    if (! sourceFiles.isEmpty() && qgetenv("QTCREATOR_NO_CODE_INDEXER").isNull()) {
        const QMap<QString, QByteArray> workingCopy = buildWorkingCopyList();

        QFuture<void> result = QtConcurrent::run(&CppModelManager::parse, this,
                                                 sourceFiles, workingCopy);

        if (sourceFiles.count() > 1) {
            m_core->progressManager()->addTask(result, tr("Indexing"),
                            CppTools::Constants::TASK_INDEX,
                            Core::ProgressManagerInterface::CloseOnSuccess);
        }
        return result;
    }
    return QFuture<void>();
}

/*!
    \fn    void CppModelManager::editorOpened(Core::IEditor *editor)
    \brief If a C++ editor is opened, the model manager listens to content changes
           in order to update the CppCodeModel accordingly. It also updates the
           CppCodeModel for the first time with this editor.

    \sa    void CppModelManager::editorContentsChanged()
 */
void CppModelManager::editorOpened(Core::IEditor *editor)
{
    if (isCppEditor(editor)) {
        TextEditor::ITextEditor *textEditor = qobject_cast<TextEditor::ITextEditor *>(editor);
        Q_ASSERT(textEditor != 0);

        CppEditorSupport *editorSupport = new CppEditorSupport(this);
        editorSupport->setTextEditor(textEditor);
        m_editorSupport[textEditor] = editorSupport;

        // ### move in CppEditorSupport
        connect(editor, SIGNAL(tooltipRequested(TextEditor::ITextEditor*, QPoint, int)),
                m_hoverHandler, SLOT(showToolTip(TextEditor::ITextEditor*, QPoint, int)));

        // ### move in CppEditorSupport
        connect(editor, SIGNAL(contextHelpIdRequested(TextEditor::ITextEditor*, int)),
                m_hoverHandler, SLOT(updateContextHelpId(TextEditor::ITextEditor*, int)));
    }
}

void CppModelManager::editorAboutToClose(Core::IEditor *editor)
{
    if (isCppEditor(editor)) {
        TextEditor::ITextEditor *textEditor = qobject_cast<TextEditor::ITextEditor *>(editor);
        Q_ASSERT(textEditor != 0);

        CppEditorSupport *editorSupport = m_editorSupport.value(textEditor);
        m_editorSupport.remove(textEditor);
        delete editorSupport;
    }
}

bool CppModelManager::isCppEditor(Core::IEditor *editor) const
{
    Core::UniqueIDManager *uidm = m_core->uniqueIDManager();
    const int uid = uidm->uniqueIdentifier(ProjectExplorer::Constants::LANG_CXX);
    return editor->context().contains(uid);
}

void CppModelManager::emitDocumentUpdated(Document::Ptr doc)
{ emit documentUpdated(doc); }

void CppModelManager::onDocumentUpdated(Document::Ptr doc)
{
    const QString fileName = doc->fileName();
    m_documents[fileName] = doc;
    QList<Core::IEditor *> openedEditors = m_core->editorManager()->openedEditors();
    foreach (Core::IEditor *editor, openedEditors) {
        if (editor->file()->fileName() == fileName) {
            TextEditor::ITextEditor *textEditor = qobject_cast<TextEditor::ITextEditor *>(editor);
            if (! textEditor)
                continue;

            TextEditor::BaseTextEditor *ed = qobject_cast<TextEditor::BaseTextEditor *>(textEditor->widget());
            if (! ed)
                continue;

            QList<TextEditor::BaseTextEditor::BlockRange> blockRanges;

            foreach (const Document::Block block, doc->skippedBlocks()) {
                blockRanges.append(TextEditor::BaseTextEditor::BlockRange(block.begin(), block.end()));
            }
            ed->setIfdefedOutBlocks(blockRanges);

            QList<QTextEdit::ExtraSelection> selections;

            // set up the format for the errors
            QTextCharFormat errorFormat;
            errorFormat.setUnderlineStyle(QTextCharFormat::WaveUnderline);
            errorFormat.setUnderlineColor(Qt::red);

            // set up the format for the warnings.
            QTextCharFormat warningFormat;
            warningFormat.setUnderlineStyle(QTextCharFormat::WaveUnderline);
            warningFormat.setUnderlineColor(Qt::darkYellow);

            QSet<int> lines;
            foreach (const Document::DiagnosticMessage m, doc->diagnosticMessages()) {
                if (m.fileName() != fileName)
                    continue;
                else if (lines.contains(m.line()))
                    continue;
                else if (lines.size() == MAX_SELECTION_COUNT)
                    break; // we're done.

                lines.insert(m.line());

                QTextEdit::ExtraSelection sel;
                if (m.isWarning())
                    sel.format = warningFormat;
                else
                    sel.format = errorFormat;

                QTextCursor c(ed->document()->findBlockByNumber(m.line() - 1));
                const QString text = c.block().text();
                for (int i = 0; i < text.size(); ++i) {
                    if (! text.at(i).isSpace()) {
                        c.setPosition(c.position() + i);
                        break;
                    }
                }
                c.movePosition(QTextCursor::EndOfBlock, QTextCursor::KeepAnchor);
                sel.cursor = c;
                selections.append(sel);
            }
            ed->setExtraExtraSelections(selections);
            break;
        }
    }
}

void CppModelManager::onAboutToRemoveProject(ProjectExplorer::Project *project)
{
    m_projects.remove(project);
    GC();
}

void CppModelManager::onSessionUnloaded()
{
    if (m_core->progressManager())
        m_core->progressManager()->cancelTasks(CppTools::Constants::TASK_INDEX);
}

void CppModelManager::parse(QFutureInterface<void> &future,
                            CppModelManager *model,
                            QStringList files,
                            QMap<QString, QByteArray> workingCopy)
{
    Q_ASSERT(! files.isEmpty());

    // Change the priority of the background parser thread to idle.
    QThread::currentThread()->setPriority(QThread::IdlePriority);

    future.setProgressRange(0, files.size());

    CppPreprocessor preproc(model);
    preproc.setWorkingCopy(workingCopy);
    preproc.setProjectFiles(model->projectFiles());
    preproc.setIncludePaths(model->includePaths());
    preproc.setFrameworkPaths(model->frameworkPaths());

    QString conf = QLatin1String(pp_configuration_file);
    (void) preproc(conf);

    const int STEP = 10;

    for (int i = 0; i < files.size(); ++i) {
        if (future.isPaused())
            future.waitForResume();

        if (future.isCanceled())
            break;

        future.setProgressValue(i);

#ifdef CPPTOOLS_DEBUG_PARSING_TIME
        QTime tm;
        tm.start();
#endif

        QString fileName = files.at(i);
        preproc(fileName);

        if (! (i % STEP)) // Yields execution of the current thread.
            QThread::yieldCurrentThread();

#ifdef CPPTOOLS_DEBUG_PARSING_TIME
        qDebug() << fileName << "parsed in:" << tm.elapsed();
#endif
    }

    future.setProgressValue(files.size());

    // Restore the previous thread priority.
    QThread::currentThread()->setPriority(QThread::NormalPriority);
}

void CppModelManager::GC()
{
    DocumentTable documents = m_documents;

    QSet<QString> processed;
    QStringList todo = m_projectFiles;

    while (! todo.isEmpty()) {
        QString fn = todo.last();
        todo.removeLast();

        if (processed.contains(fn))
            continue;

        processed.insert(fn);

        if (Document::Ptr doc = documents.value(fn)) {
            todo += doc->includedFiles();
        }
    }

    QStringList removedFiles;
    QMutableMapIterator<QString, Document::Ptr> it(documents);
    while (it.hasNext()) {
        it.next();
        const QString fn = it.key();
        if (! processed.contains(fn)) {
            removedFiles.append(fn);
            it.remove();
        }
    }

    emit aboutToRemoveFiles(removedFiles);
    m_documents = documents;
}