/*
  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 <algorithm>
#include <QMetaEnum>
#include <QtDebug>
#include "qwt_symbol.h"

#include "plot.h"
#include "plotmanager.h"
#include "utils.h"
#include "setting_defines.h"

PlotManager::PlotManager(QWidget* plotArea, PlotMenu* menu,
                         ChannelInfoModel* infoModel, QObject* parent) :
    QObject(parent)
{
    _menu = menu;
    _plotArea = plotArea;
    _autoScaled = true;
    _yMin = 0;
    _yMax = 1;
    _xAxisAsIndex = true;
    isDemoShown = false;
    _infoModel = infoModel;
    _numOfSamples = 1;
    _plotWidth = 1;
    showSymbols = Plot::ShowSymbolsAuto;
    emptyPlot = NULL;

    // initalize layout and single widget
    isMulti = false;
    scrollArea = NULL;
    setupLayout(isMulti);
    addPlotWidget();

    // connect to  menu
    connect(menu, &PlotMenu::symbolShowChanged, this, &PlotManager:: setSymbols);

    connect(&menu->showGridAction, SELECT<bool>::OVERLOAD_OF(&QAction::toggled),
            this, &PlotManager::showGrid);
    connect(&menu->showMinorGridAction, SELECT<bool>::OVERLOAD_OF(&QAction::toggled),
            this, &PlotManager::showMinorGrid);
    connect(&menu->darkBackgroundAction, SELECT<bool>::OVERLOAD_OF(&QAction::toggled),
            this, &PlotManager::darkBackground);
    connect(&menu->showLegendAction, SELECT<bool>::OVERLOAD_OF(&QAction::toggled),
            this, &PlotManager::showLegend);
    connect(&menu->showMultiAction, SELECT<bool>::OVERLOAD_OF(&QAction::toggled),
            this, &PlotManager::setMulti);
    connect(&menu->unzoomAction, &QAction::triggered,
            this, &PlotManager::unzoom);

    // initial settings from menu actions
    showGrid(menu->showGridAction.isChecked());
    showMinorGrid(menu->showMinorGridAction.isChecked());
    darkBackground(menu->darkBackgroundAction.isChecked());
    showLegend(menu->showLegendAction.isChecked());
    setMulti(menu->showMultiAction.isChecked());

    // connect to channel info model
    if (_infoModel != NULL)     // TODO: remove when snapshots have infomodel
    {
        connect(_infoModel, &QAbstractItemModel::dataChanged,
                this, &PlotManager::onChannelInfoChanged);

        connect(_infoModel, &QAbstractItemModel::modelReset,
                [this]()
                {
                    onChannelInfoChanged(_infoModel->index(0, 0), // start
                                         _infoModel->index(_infoModel->rowCount()-1, 0), // end
                                         {}); // roles ignored
                });
    }
}

PlotManager::~PlotManager()
{
    while (curves.size())
    {
        delete curves.takeLast();
    }

    // remove all widgets
    while (plotWidgets.size())
    {
        delete plotWidgets.takeLast();
    }

    if (scrollArea != NULL) delete scrollArea;
    if (emptyPlot != NULL) delete emptyPlot;
}

void PlotManager::onChannelInfoChanged(const QModelIndex &topLeft,
                                       const QModelIndex &bottomRight,
                                       const QVector<int> &roles)
{
    int start = topLeft.row();
    int end = bottomRight.row();

    for (int ci = start; ci <= end; ci++)
    {
        QString name = topLeft.sibling(ci, ChannelInfoModel::COLUMN_NAME).data(Qt::EditRole).toString();
        QColor color = topLeft.sibling(ci, ChannelInfoModel::COLUMN_NAME).data(Qt::ForegroundRole).value<QColor>();
        bool visible = topLeft.sibling(ci, ChannelInfoModel::COLUMN_VISIBILITY).data(Qt::CheckStateRole).toBool();

        curves[ci]->setTitle(name);
        curves[ci]->setPen(color);
        curves[ci]->setVisible(visible);
        curves[ci]->setItemAttribute(QwtPlotItem::Legend, visible);

        // replot only updated widgets
        if (isMulti)
        {
            plotWidgets[ci]->updateSymbols(); // required for color change
            plotWidgets[ci]->updateLegend(curves[ci]);
            plotWidgets[ci]->setVisible(visible);
            if (visible)
            {
                plotWidgets[ci]->replot();
            }
        }
    }

    checkNoVisChannels();

    // replot single widget
    if (!isMulti)
    {
        plotWidgets[0]->updateSymbols();
        plotWidgets[0]->updateLegend();
        replot();
    }
}

void PlotManager::checkNoVisChannels()
{
    // if all channels are hidden show indicator
    bool allhidden = std::none_of(curves.cbegin(), curves.cend(),
                                  [](QwtPlotCurve* c) {return c->isVisible();});

    plotWidgets[0]->showNoChannel(allhidden);
    if (isMulti)
    {
        plotWidgets[0]->showNoChannel(allhidden);
        plotWidgets[0]->setVisible(true);
    }
}

void PlotManager::setMulti(bool enabled)
{
    if (enabled == isMulti) return;

    isMulti = enabled;

    // detach all curves
    for (auto curve : curves)
    {
        curve->detach();
    }

    // remove all widgets
    while (plotWidgets.size())
    {
        delete plotWidgets.takeLast();
    }

    // setup new layout
    setupLayout(isMulti);

    if (isMulti)
    {
        // add new widgets and attach
        for (auto curve : curves)
        {
            auto plot = addPlotWidget();
            plot->setVisible(curve->isVisible());
            curve->attach(plot);
        }
    }
    else
    {
        // add a single widget
        auto plot = addPlotWidget();

        // attach all curves
        for (auto curve : curves)
        {
            curve->attach(plot);
        }
    }

    checkNoVisChannels();
}

void PlotManager::setupLayout(bool multiPlot)
{
    // delete previous layout if it exists
    if (_plotArea->layout() != 0)
    {
        delete _plotArea->layout();
    }

    if (multiPlot)
    {
        // setup a scroll area
        scrollArea = new QScrollArea();
        auto scrolledPlotArea = new QWidget(scrollArea);
        scrollArea->setWidget(scrolledPlotArea);
        scrollArea->setWidgetResizable(true);

        _plotArea->setLayout(new QVBoxLayout());
        _plotArea->layout()->addWidget(scrollArea);
        _plotArea->layout()->setContentsMargins(0,0,0,0);

        layout = new QVBoxLayout(scrolledPlotArea);
    }
    else
    {
        // delete scrollArea left from multi layout
        if (scrollArea != NULL)
        {
            delete scrollArea;
            scrollArea = NULL;
        }

        layout = new QVBoxLayout(_plotArea);
    }

    layout->setContentsMargins(2,2,2,2);
    layout->setSpacing(1);
}

Plot* PlotManager::addPlotWidget()
{
    auto plot = new Plot();
    plotWidgets.append(plot);
    layout->addWidget(plot);

    plot->darkBackground(_menu->darkBackgroundAction.isChecked());
    plot->showGrid(_menu->showGridAction.isChecked());
    plot->showMinorGrid(_menu->showMinorGridAction.isChecked());
    plot->showLegend(_menu->showLegendAction.isChecked());
    plot->setSymbols(_menu->showSymbols());

    plot->showDemoIndicator(isDemoShown);
    plot->setYAxis(_autoScaled, _yMin, _yMax);
    plot->setNumOfSamples(_numOfSamples);

    plot->setPlotWidth(_plotWidth);
    if (_xAxisAsIndex)
    {
        plot->setXAxis(0, _numOfSamples);
    }
    else
    {
        plot->setXAxis(_xMin, _xMax);
    }

    return plot;
}

void PlotManager::addCurve(QString title, FrameBuffer* buffer)
{
    auto curve = new QwtPlotCurve(title);
    auto series = new FrameBufferSeries(buffer);
    series->setXAxis(_xAxisAsIndex, _xMin, _xMax);
    curve->setSamples(series);
    _addCurve(curve);
}

void PlotManager::addCurve(QString title, QVector<QPointF> data)
{
    auto curve = new QwtPlotCurve(title);
    curve->setSamples(data);
    _addCurve(curve);
}

void PlotManager::_addCurve(QwtPlotCurve* curve)
{
    // store and init the curve
    curves.append(curve);

    unsigned index = curves.size()-1;
    auto color = _infoModel->color(index);
    curve->setPen(color);

    // create the plot for the curve if we are on multi display
    Plot* plot;
    if (isMulti)
    {
        // create a new plot widget
        plot = addPlotWidget();
    }
    else
    {
        plot = plotWidgets[0];
    }

    // show the curve
    curve->attach(plot);
    plot->replot();
}

void PlotManager::removeCurves(unsigned number)
{
    for (unsigned i = 0; i < number; i++)
    {
        if (!curves.isEmpty())
        {
            delete curves.takeLast();
            if (isMulti) // delete corresponding widget as well
            {
                delete plotWidgets.takeLast();
            }
        }
    }
}

unsigned PlotManager::numOfCurves()
{
    return curves.size();
}

void PlotManager::setTitle(unsigned index, QString title)
{
    curves[index]->setTitle(title);

    plotWidget(index)->replot();
}

Plot* PlotManager::plotWidget(unsigned curveIndex)
{
    if (isMulti)
    {
        return plotWidgets[curveIndex];
    }
    else
    {
        return plotWidgets[0];
    }
}

void PlotManager::replot()
{
    for (auto plot : plotWidgets)
    {
        plot->replot();
    }
}

void PlotManager::showGrid(bool show)
{
    for (auto plot : plotWidgets)
    {
        plot->showGrid(show);
    }
}

void PlotManager::showMinorGrid(bool show)
{
    for (auto plot : plotWidgets)
    {
        plot->showMinorGrid(show);
    }
}

void PlotManager::showLegend(bool show)
{
    for (auto plot : plotWidgets)
    {
        plot->showLegend(show);
    }
}

void PlotManager::showDemoIndicator(bool show)
{
    isDemoShown = show;
    for (auto plot : plotWidgets)
    {
        plot->showDemoIndicator(show);
    }
}

void PlotManager::unzoom()
{
    for (auto plot : plotWidgets)
    {
        plot->unzoom();
    }
}

void PlotManager::darkBackground(bool enabled)
{
    for (auto plot : plotWidgets)
    {
        plot->darkBackground(enabled);
    }
}

void PlotManager::setSymbols(Plot::ShowSymbols shown)
{
    showSymbols = shown;
    for (auto plot : plotWidgets)
    {
        plot->setSymbols(shown);
    }
}

void PlotManager::setYAxis(bool autoScaled, double yAxisMin, double yAxisMax)
{
    _autoScaled = autoScaled;
    _yMin = yAxisMin;
    _yMax = yAxisMax;
    for (auto plot : plotWidgets)
    {
        plot->setYAxis(autoScaled, yAxisMin, yAxisMax);
    }
}

void PlotManager::setXAxis(bool asIndex, double xMin, double xMax)
{
    _xAxisAsIndex = asIndex;
    _xMin = xMin;
    _xMax = xMax;
    for (auto curve : curves)
    {
        // TODO: what happens when addCurve(QVector) is used?
        FrameBufferSeries* series = static_cast<FrameBufferSeries*>(curve->data());
        series->setXAxis(asIndex, xMin, xMax);
    }
    for (auto plot : plotWidgets)
    {
        if (asIndex)
        {
            plot->setXAxis(0, _numOfSamples);
        }
        else
        {
            plot->setXAxis(xMin, xMax);
        }
    }
    replot();
}

void PlotManager::flashSnapshotOverlay()
{
    for (auto plot : plotWidgets)
    {
        plot->flashSnapshotOverlay(_menu->darkBackgroundAction.isChecked());
    }
}

void PlotManager::setNumOfSamples(unsigned value)
{
    _numOfSamples = value;
    for (auto plot : plotWidgets)
    {
        plot->setNumOfSamples(value);
        if (_xAxisAsIndex) plot->setXAxis(0, value);
    }
}

void PlotManager::setPlotWidth(double width)
{
    _plotWidth = width;
    for (auto plot : plotWidgets)
    {
        plot->setPlotWidth(width);
    }
}