/*

  Copyright © 2017 Hasan Yavuz Özderya

  This file is part of serialplot.

  serialplot 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 3 of the License, or

  (at your option) any later version.

  serialplot 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 serialplot.  If not, see <http://www.gnu.org/licenses/>.

*/

#include <QVariant>

#include <QMessageBox>

#include <QCheckBox>

#include <math.h>

#include "color_selector.hpp"

#include "plotcontrolpanel.h"

#include "ui_plotcontrolpanel.h"

#include "setting_defines.h"

/// Confirm if #samples is being set to a value greater than this

const int NUMSAMPLES_CONFIRM_AT = 10000;

/// Used for scale range selection combobox

struct Range

{

    double rmin;

    double rmax;

};

Q_DECLARE_METATYPE(Range);

PlotControlPanel::PlotControlPanel(QWidget *parent) :

    QWidget(parent),

    ui(new Ui::PlotControlPanel)

{

    ui->setupUi(this);

    warnNumOfSamples = true;    // TODO: load from settings

    _numOfSamples = ui->spNumOfSamples->value();

    // set limits for axis limit boxes

    ui->spYmin->setRange((-1) * std::numeric_limits<double>::max(),

                         std::numeric_limits<double>::max());

    ui->spYmax->setRange((-1) * std::numeric_limits<double>::max(),

                         std::numeric_limits<double>::max());

    // connect signals

    connect(ui->spNumOfSamples, SIGNAL(valueChanged(int)),

            this, SLOT(onNumOfSamples(int)));

    connect(ui->cbAutoScale, &QCheckBox::toggled,

            this, &PlotControlPanel::onAutoScaleChecked);

    connect(ui->spYmax, SIGNAL(valueChanged(double)),

            this, SLOT(onYScaleChanged()));

    connect(ui->spYmin, SIGNAL(valueChanged(double)),

            this, SLOT(onYScaleChanged()));

    // init scale range preset list

    for (int nbits = 8; nbits <= 24; nbits++) // signed binary formats

    {

        int rmax = pow(2, nbits-1)-1;

        int rmin = -rmax-1;

        Range r = {double(rmin),  double(rmax)};

        ui->cbRangePresets->addItem(

            QString().sprintf("Signed %d bits %d to +%d", nbits, rmin, rmax),

            QVariant::fromValue(r));

    }

    for (int nbits = 8; nbits <= 24; nbits++) // unsigned binary formats

    {

        int rmax = pow(2, nbits)-1;

        ui->cbRangePresets->addItem(

            QString().sprintf("Unsigned %d bits %d to +%d", nbits, 0, rmax),

            QVariant::fromValue(Range{0, double(rmax)}));

    }

    ui->cbRangePresets->addItem("-1 to +1", QVariant::fromValue(Range{-1, +1}));

    ui->cbRangePresets->addItem("0 to +1", QVariant::fromValue(Range{0, +1}));

    ui->cbRangePresets->addItem("-100 to +100", QVariant::fromValue(Range{-100, +100}));

    ui->cbRangePresets->addItem("0 to +100", QVariant::fromValue(Range{0, +100}));

    QObject::connect(ui->cbRangePresets, SIGNAL(activated(int)),

                     this, SLOT(onRangeSelected()));

}

PlotControlPanel::~PlotControlPanel()

{

    delete ui;

}

unsigned PlotControlPanel::numOfSamples()

{

    return ui->spNumOfSamples->value();

}

void PlotControlPanel::onNumOfSamples(int value)

{

    if (warnNumOfSamples && value > NUMSAMPLES_CONFIRM_AT)

    {

        // ask confirmation

        if (!askNSConfirmation(value))

        {

            // revert to old value

            disconnect(ui->spNumOfSamples, SIGNAL(valueChanged(int)),

                       this, SLOT(onNumOfSamples(int)));

            ui->spNumOfSamples->setValue(_numOfSamples);

            connect(ui->spNumOfSamples, SIGNAL(valueChanged(int)),

                    this, SLOT(onNumOfSamples(int)));

            return;

        }

    }

    _numOfSamples = value;

    emit numOfSamplesChanged(value);

}

bool PlotControlPanel::askNSConfirmation(int value)

{

    auto text = tr("Setting number of samples to a too big value "

                   "(>%1) can seriously impact the performance of "

                   "the application and cause freezes. Are you sure you "

                   "want to change the number of samples to %2?")

        .arg(QString::number(NUMSAMPLES_CONFIRM_AT), QString::number(value));

    // TODO: parent the mainwindow

    QMessageBox mb(QMessageBox::Warning,

                   tr("Confirm Number of Samples"),

                   text,

                   QMessageBox::Apply | QMessageBox::Cancel,

                   this);

    auto cb = new QCheckBox("Don't show this again.");

    connect(cb, &QCheckBox::stateChanged, [this](int state)

            {

                warnNumOfSamples = (state == Qt::Unchecked);

            });

    mb.setCheckBox(cb);

    return mb.exec() == QMessageBox::Apply;

}

void PlotControlPanel::onAutoScaleChecked(bool checked)

{

    if (checked)

    {

        ui->lYmin->setEnabled(false);

        ui->lYmax->setEnabled(false);

        ui->spYmin->setEnabled(false);

        ui->spYmax->setEnabled(false);

        emit scaleChanged(true); // autoscale

    }

    else

    {

        ui->lYmin->setEnabled(true);

        ui->lYmax->setEnabled(true);

        ui->spYmin->setEnabled(true);

        ui->spYmax->setEnabled(true);

        emit scaleChanged(false, ui->spYmin->value(), ui->spYmax->value());

    }

}

void PlotControlPanel::onYScaleChanged()

{

    emit scaleChanged(false, ui->spYmin->value(), ui->spYmax->value());

}

bool PlotControlPanel::autoScale()

{

    return ui->cbAutoScale->isChecked();

}

double PlotControlPanel::yMax()

{

    return ui->spYmax->value();

}

double PlotControlPanel::yMin()

{

    return ui->spYmin->value();

}

void PlotControlPanel::onRangeSelected()

{

    Range r = ui->cbRangePresets->currentData().value<Range>();

    ui->spYmin->setValue(r.rmin);

    ui->spYmax->setValue(r.rmax);

    ui->cbAutoScale->setChecked(false);

}

void PlotControlPanel::setChannelInfoModel(ChannelInfoModel* model)

{

    ui->tvChannelInfo->setModel(model);

    // channel color selector

    connect(ui->tvChannelInfo->selectionModel(), &QItemSelectionModel::currentRowChanged,

            [this](const QModelIndex &current, const QModelIndex &previous)

            {

                ui->colorSelector->setColor(color);

            });

    connect(ui->colorSelector, &color_widgets::ColorSelector::colorChanged,

            [this](QColor color)

            {

                auto index = ui->tvChannelInfo->selectionModel()->currentIndex();

                ui->tvChannelInfo->model()->setData(index, color, Qt::ForegroundRole);

            });

    connect(model, &QAbstractItemModel::dataChanged,

            [this](const QModelIndex & topLeft, const QModelIndex & bottomRight, const QVector<int> & roles = QVector<int> ())

            {

                auto current = ui->tvChannelInfo->selectionModel()->currentIndex();

                // no current selection

                if (!current.isValid()) return;

                auto mod = ui->tvChannelInfo->model();

                QColor color = mod->data(current, Qt::ForegroundRole).value<QColor>();

                // temporarily block signals because `setColor` emits `colorChanged`

                bool wasBlocked = ui->colorSelector->blockSignals(true);

                ui->colorSelector->setColor(color);

                ui->colorSelector->blockSignals(wasBlocked);

            });

}

void PlotControlPanel::saveSettings(QSettings* settings)

{

    settings->beginGroup(SettingGroup_Plot);

    settings->setValue(SG_Plot_NumOfSamples, numOfSamples());

    settings->setValue(SG_Plot_AutoScale, autoScale());

    settings->setValue(SG_Plot_YMax, yMax());

    settings->setValue(SG_Plot_YMin, yMin());

    settings->endGroup();

}

void PlotControlPanel::loadSettings(QSettings* settings)

{

    settings->beginGroup(SettingGroup_Plot);

    ui->spNumOfSamples->setValue(

        settings->value(SG_Plot_NumOfSamples, numOfSamples()).toInt());

    ui->cbAutoScale->setChecked(

        settings->value(SG_Plot_AutoScale, autoScale()).toBool());

    ui->spYmax->setValue(settings->value(SG_Plot_YMax, yMax()).toDouble());

    ui->spYmin->setValue(settings->value(SG_Plot_YMin, yMin()).toDouble());

    settings->endGroup();

}