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** Copyright (C) 2015 Dmitry Savchenko
** Copyright (C) 2015 Vasiliy Sorokin
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#include "todoitemsprovider.h"
#include "constants.h"
#include "cpptodoitemsscanner.h"
#include "qmljstodoitemsscanner.h"
#include "todoitemsmodel.h"
#include "todoitemsscanner.h"

#include <projectexplorer/nodesvisitor.h>
#include <projectexplorer/projectexplorer.h>
#include <projectexplorer/projectnodes.h>
#include <projectexplorer/projecttree.h>
#include <coreplugin/editormanager/editormanager.h>
#include <coreplugin/idocument.h>
#include <projectexplorer/session.h>

#include <QTimer>

using namespace ProjectExplorer;

namespace Todo {
namespace Internal {

TodoItemsProvider::TodoItemsProvider(Settings settings, QObject *parent) :
    QObject(parent),
    m_settings(settings)
{
    setupItemsModel();
    setupStartupProjectBinding();
    setupCurrentEditorBinding();
    setupUpdateListTimer();
    createScanners();
}

TodoItemsModel *TodoItemsProvider::todoItemsModel()
{
    return m_itemsModel;
}

void TodoItemsProvider::settingsChanged(const Settings &newSettings)
{
    if (newSettings.keywords != m_settings.keywords) {
        foreach (TodoItemsScanner *scanner, m_scanners)
            scanner->setParams(newSettings.keywords);
    }

    m_settings = newSettings;

    updateList();
}

void TodoItemsProvider::projectSettingsChanged(Project *project)
{
    Q_UNUSED(project);
    updateList();
}

void TodoItemsProvider::updateList()
{
    m_itemsList.clear();

    // Show only items of the current file if any
    if (m_settings.scanningScope == ScanningScopeCurrentFile) {
        if (m_currentEditor)
            m_itemsList = m_itemsHash.value(m_currentEditor->document()->filePath().toString());
    // Show only items of the current sub-project
    } else if (m_settings.scanningScope == ScanningScopeSubProject) {
        if (m_startupProject)
            setItemsListWithinSubproject();
    // Show only items of the startup project if any
    } else if (m_startupProject) {
        setItemsListWithinStartupProject();
    }

    m_itemsModel->todoItemsListUpdated();
}

void TodoItemsProvider::createScanners()
{
    qRegisterMetaType<QList<TodoItem> >("QList<TodoItem>");

    if (CppTools::CppModelManager::instance())
        m_scanners << new CppTodoItemsScanner(m_settings.keywords, this);

    if (QmlJS::ModelManagerInterface::instance())
        m_scanners << new QmlJsTodoItemsScanner(m_settings.keywords, this);

    foreach (TodoItemsScanner *scanner, m_scanners) {
        connect(scanner, SIGNAL(itemsFetched(QString,QList<TodoItem>)), this,
            SLOT(itemsFetched(QString,QList<TodoItem>)), Qt::QueuedConnection);
    }
}

void TodoItemsProvider::setItemsListWithinStartupProject()
{
    QHashIterator<QString, QList<TodoItem> > it(m_itemsHash);
    QSet<QString> fileNames = QSet<QString>::fromList(m_startupProject->files(Project::ExcludeGeneratedFiles));

    QVariantMap settings = m_startupProject->namedSettings(QLatin1String(Constants::SETTINGS_NAME_KEY)).toMap();

    while (it.hasNext()) {
        it.next();
        QString fileName = it.key();
        if (fileNames.contains(fileName)) {
            bool skip = false;
            for (const QVariant &pattern : settings[QLatin1String(Constants::EXCLUDES_LIST_KEY)].toList()) {
                QRegExp re(pattern.toString());
                if (re.indexIn(fileName) != -1) {
                    skip = true;
                    break;
                }
            }
            if (!skip)
                m_itemsList << it.value();
        }
    }
}

void TodoItemsProvider::setItemsListWithinSubproject()
{
    // TODO prefer current editor as source of sub-project
    Node *node = ProjectTree::currentNode();
    if (node) {
        ProjectNode *projectNode = node->projectNode();
        if (projectNode) {

            FindAllFilesVisitor filesVisitor;
            projectNode->accept(&filesVisitor);

            // files must be both in the current subproject and the startup-project.
            QSet<Utils::FileName> subprojectFileNames =
                    QSet<Utils::FileName>::fromList(filesVisitor.filePaths());
            QSet<QString> fileNames = QSet<QString>::fromList(
                        m_startupProject->files(ProjectExplorer::Project::ExcludeGeneratedFiles));
            QHashIterator<QString, QList<TodoItem> > it(m_itemsHash);
            while (it.hasNext()) {
                it.next();
                if (subprojectFileNames.contains(Utils::FileName::fromString(it.key()))
                        && fileNames.contains(it.key())) {
                    m_itemsList << it.value();
                }
            }
        }
    }
}

void TodoItemsProvider::itemsFetched(const QString &fileName, const QList<TodoItem> &items)
{
    // Replace old items with new ones
    m_itemsHash.insert(fileName, items);

    m_shouldUpdateList = true;
}

void TodoItemsProvider::startupProjectChanged(Project *project)
{
    m_startupProject = project;
    updateList();
}

void TodoItemsProvider::projectsFilesChanged()
{
    updateList();
}

void TodoItemsProvider::currentEditorChanged(Core::IEditor *editor)
{
    m_currentEditor = editor;
    if (m_settings.scanningScope == ScanningScopeCurrentFile
            || m_settings.scanningScope == ScanningScopeSubProject) {
        updateList();
    }
}

void TodoItemsProvider::updateListTimeoutElapsed()
{
    if (m_shouldUpdateList) {
        m_shouldUpdateList = false;
        updateList();
    }
}

void TodoItemsProvider::setupStartupProjectBinding()
{
    m_startupProject = SessionManager::startupProject();
    connect(SessionManager::instance(), SIGNAL(startupProjectChanged(ProjectExplorer::Project*)),
        SLOT(startupProjectChanged(ProjectExplorer::Project*)));
    connect(ProjectExplorerPlugin::instance(), SIGNAL(fileListChanged()), SLOT(projectsFilesChanged()));
}

void TodoItemsProvider::setupCurrentEditorBinding()
{
    m_currentEditor = Core::EditorManager::currentEditor();
    connect(Core::EditorManager::instance(), SIGNAL(currentEditorChanged(Core::IEditor*)),
        SLOT(currentEditorChanged(Core::IEditor*)));
}

void TodoItemsProvider::setupUpdateListTimer()
{
    m_shouldUpdateList = false;
    QTimer *timer = new QTimer(this);
    connect(timer, &QTimer::timeout, this, &TodoItemsProvider::updateListTimeoutElapsed);
    timer->start(Constants::OUTPUT_PANE_UPDATE_INTERVAL);
}

void TodoItemsProvider::setupItemsModel()
{
    m_itemsModel = new TodoItemsModel(this);
    m_itemsModel->setTodoItemsList(&m_itemsList);
}

}
}