/*
 * This program source code file is part of KiCad, a free EDA CAD application.
 *
 * Copyright (C) 2017 CERN
 * Author: Tomasz Wlostowski <tomasz.wlostowski@cern.ch>
*
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, you may find one here:
 * http://www.gnu.org/licenses/old-licenses/gpl-2.0.html
 * or you may search the http://www.gnu.org website for the version 2 license,
 * or you may write to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA
 */

#ifndef __PROGRESS_REPORTER
#define __PROGRESS_REPORTER

#include <mutex>
#include <atomic>

#include <wx/progdlg.h>
#include <wx/gauge.h>
#if wxCHECK_VERSION(3, 1, 0)
#include <wx/appprogress.h>
#endif

/**
 * A progress reporter for use in multi-threaded environments.  The various advancement
 * and message methods can be called from sub-threads.  The KeepRefreshing method *MUST*
 * be called only from the main thread (primarily a MSW requirement, which won't allow
 * access to UI objects allocated from a separate thread).
 */
class PROGRESS_REPORTER
{
public:

    PROGRESS_REPORTER( int aNumPhases );
    PROGRESS_REPORTER( const PROGRESS_REPORTER& ) = delete;

    virtual ~PROGRESS_REPORTER()
    {
    }

    /**
     * sets the number of phases
     */
    void SetNumPhases( int aNumPhases );
    void AddPhases( int aNumPhases );

    /**
     * initialize the aPhase virtual zone of the dialog progress bar
     */
    virtual void BeginPhase( int aPhase );

    /**
     * Uses the next available virtual zone of the dialog progress bar
     */
    virtual void AdvancePhase();

    /**
     * Uses the next available virtual zone of the dialog progress bar and updates
     * the message.
     */
    virtual void AdvancePhase( const wxString& aMessage );

    /**
     * Display aMessage in the progress bar dialog
     */
    virtual void Report( const wxString& aMessage );

    /**
     * Set the progress value to aProgress (0..1)
     */
    virtual void SetCurrentProgress( double aProgress );

    /**
     * Fix the value thar gives the 100 percent progress bar length
     * (inside the current virtual zone)
     */
    void SetMaxProgress( int aMaxProgress );

    /**
     * Increment the progress bar length (inside the current virtual zone)
     */
    void AdvanceProgress();

    /**
     * Update the UI dialog.  *MUST* only be called from the main thread.
     * Returns false if the user clicked Cancel.
     */
    bool KeepRefreshing( bool aWait = false );

    /** change the title displayed on the window caption
     * *MUST* only be called from the main thread.
     * Has meaning only for some reporters.
     * Do nothing for others
     */
    virtual void SetTitle( const wxString& aTitle ) {}

    bool IsCancelled() const { return m_cancelled.load(); }

protected:

    int currentProgress() const;

    virtual bool updateUI() = 0;

    wxString           m_rptMessage;
    mutable std::mutex m_mutex;
    std::atomic_int    m_phase;
    std::atomic_int    m_numPhases;
    std::atomic_int    m_progress;
    std::atomic_int    m_maxProgress;
    std::atomic_bool   m_cancelled;
};

/**
* Multi-thread safe progress reporter dialog, intended for use of tasks that paralleize reporting back of work status
* See PROGRESS_REPORTER
*/
class WX_PROGRESS_REPORTER : public PROGRESS_REPORTER, public wxProgressDialog
{
public:
    /**
     * Ctor: the PROGRESS_REPORTER will stay on top of aParent.
     * the style is wxPD_AUTO_HIDE | wxPD_CAN_ABORT | wxPD_ELAPSED_TIME
     * @param aParent is the wxDialog of Frame that manage this.
     * @param aTitle is the dialog progress title
     * @param aNumPhases is the number of "virtual sections" of the progress bar
     * aNumPhases = 1 is the usual progress bar
     * aNumPhases = n creates n virtual progress bar zones: a 0 to 100 percent width
     * of a virtual zone fills 0 to 1/n progress bar full size of the nth virtual zone index
     * @param aCanAbort is true if the abort button should be shown
     * @param aReserveSpaceForMessage will ensure that the dialog is laid out for status messages,
     * preventing layout issues on Windows when reporting a message after the initial layout
     */
    WX_PROGRESS_REPORTER( wxWindow* aParent, const wxString& aTitle, int aNumPhases,
                          bool aCanAbort = true, bool aReserveSpaceForMessage = true );
    ~WX_PROGRESS_REPORTER();

    /** change the title displayed on the window caption
     */
    virtual void SetTitle( const wxString& aTitle ) override
    {
        wxProgressDialog::SetTitle( aTitle );
    }

private:
#if wxCHECK_VERSION(3, 1, 0)
    wxAppProgressIndicator m_appProgressIndicator;
#endif

    virtual bool updateUI() override;
};


class GAUGE_PROGRESS_REPORTER : public PROGRESS_REPORTER, public wxGauge
{
public:
    /**
     * @param aParent is the parent of the wxGauge control
     * @param aNumPhases is the number of "virtual sections" of the progress bar
     * aNumPhases = 1 is the usual progress bar
     * aNumPhases = n creates n virtual progress bar zones: a 0 to 100 percent width
     * of a virtual zone fills 0 to 1/n progress bar full size of the nth virtual zone index
     */
    GAUGE_PROGRESS_REPORTER( wxWindow* aParent, int aNumPhases );

private:

    bool updateUI() override;
};

#endif