/****************************************************************************
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** Copyright (C) 2016 The Qt Company Ltd.
** Contact: https://www.qt.io/licensing/
**
** This file is part of Qt Creator.
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** GNU General Public License Usage
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** 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
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#pragma once

#include "core_global.h"
#include "helpitem.h"
#include "id.h"

#include <QList>
#include <QObject>
#include <QPointer>
#include <QWidget>

#include <functional>

namespace Core {

class CORE_EXPORT Context
{
public:
    Context() = default;

    explicit Context(Id c1) { add(c1); }
    Context(Id c1, Id c2) { add(c1); add(c2); }
    Context(Id c1, Id c2, Id c3) { add(c1); add(c2); add(c3); }
    bool contains(Id c) const { return d.contains(c); }
    int size() const { return d.size(); }
    bool isEmpty() const { return d.isEmpty(); }
    Id at(int i) const { return d.at(i); }

    // FIXME: Make interface slimmer.
    using const_iterator = QList<Id>::const_iterator;
    const_iterator begin() const { return d.begin(); }
    const_iterator end() const { return d.end(); }
    int indexOf(Id c) const { return d.indexOf(c); }
    void removeAt(int i) { d.removeAt(i); }
    void prepend(Id c) { d.prepend(c); }
    void add(const Context &c) { d += c.d; }
    void add(Id c) { d.append(c); }
    bool operator==(const Context &c) const { return d == c.d; }

private:
    QList<Id> d;
};

class CORE_EXPORT IContext : public QObject
{
    Q_OBJECT
public:
    IContext(QObject *parent = nullptr) : QObject(parent) {}

    virtual Context context() const { return m_context; }
    virtual QWidget *widget() const { return m_widget; }
    using HelpCallback = std::function<void(const HelpItem &item)>;
    virtual void contextHelp(const HelpCallback &callback) const { callback(m_contextHelp); }

    virtual void setContext(const Context &context) { m_context = context; }
    virtual void setWidget(QWidget *widget) { m_widget = widget; }
    virtual void setContextHelp(const HelpItem &id) { m_contextHelp = id; }

protected:
    Context m_context;
    QPointer<QWidget> m_widget;
    HelpItem m_contextHelp;
};

} // namespace Core
CORE_EXPORT QDebug operator<<(QDebug debug, const Core::Context &context);
