/*
 * 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>

/**
 * 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()
        {
        }

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

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

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

        /**
         * Fix the value thar gives the 100 precent 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 ) {}


    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;
};


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
     */
    WX_PROGRESS_REPORTER( wxWindow* aParent, const wxString& aTitle, int aNumPhases,
                          bool aCanAbort = true );
    ~WX_PROGRESS_REPORTER();

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

private:

    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
