/*
  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 "mainwindow.h"
#include "ui_mainwindow.h"
#include <QByteArray>
#include <QApplication>
#include <QFileDialog>
#include <QMessageBox>
#include <QFile>
#include <QTextStream>
#include <QMenu>
#include <QDesktopServices>
#include <QMap>
#include <QtDebug>
#include <qwt_plot.h>
#include <limits.h>
#include <cmath>
#include <iostream>

#include <plot.h>

#include "framebufferseries.h"
#include "utils.h"
#include "defines.h"
#include "version.h"
#include "setting_defines.h"

#if defined(Q_OS_WIN) && defined(QT_STATIC)
#include <QtPlugin>
Q_IMPORT_PLUGIN(QWindowsIntegrationPlugin)
#endif

const QMap<int, QString> panelSettingMap({
        {0, "Port"},
        {1, "DataFormat"},
        {2, "Plot"},
        {3, "Commands"}
    });

MainWindow::MainWindow(QWidget *parent) :
    QMainWindow(parent),
    ui(new Ui::MainWindow),
    aboutDialog(this),
    portControl(&serialPort),
    channelMan(1, 1, this),
    snapshotMan(this, &channelMan),
    commandPanel(&serialPort),
    dataFormatPanel(&serialPort, &channelMan)
{
    ui->setupUi(this);

    plotMan = new PlotManager(ui->plotArea, channelMan.infoModel());

    ui->tabWidget->insertTab(0, &portControl, "Port");
    ui->tabWidget->insertTab(1, &dataFormatPanel, "Data Format");
    ui->tabWidget->insertTab(2, &plotControlPanel, "Plot");
    ui->tabWidget->insertTab(3, &commandPanel, "Commands");
    ui->tabWidget->setCurrentIndex(0);
    auto tbPortControl = portControl.toolBar();
    addToolBar(tbPortControl);

    ui->plotToolBar->addAction(snapshotMan.takeSnapshotAction());
    ui->menuBar->insertMenu(ui->menuHelp->menuAction(), snapshotMan.menu());
    ui->menuBar->insertMenu(ui->menuHelp->menuAction(), commandPanel.menu());

    connect(&commandPanel, &CommandPanel::focusRequested, [this]()
            {
                this->ui->tabWidget->setCurrentWidget(&commandPanel);
            });

    tbPortControl->setObjectName("tbPortControl");
    ui->plotToolBar->setObjectName("tbPlot");

    setupAboutDialog();

    // init view menu
    for (auto a : plotMan->menuActions())
    {
        ui->menuView->addAction(a);
    }

    ui->menuView->addSeparator();

    QMenu* tbMenu = ui->menuView->addMenu("Toolbars");
    tbMenu->addAction(ui->plotToolBar->toggleViewAction());
    tbMenu->addAction(portControl.toolBar()->toggleViewAction());

    // init UI signals

    // Help menu signals
    QObject::connect(ui->actionHelpAbout, &QAction::triggered,
              &aboutDialog, &QWidget::show);

    QObject::connect(ui->actionReportBug, &QAction::triggered,
                     [](){QDesktopServices::openUrl(QUrl(BUG_REPORT_URL));});

    // File menu signals
    QObject::connect(ui->actionExportCsv, &QAction::triggered,
                     this, &MainWindow::onExportCsv);

    QObject::connect(ui->actionSaveSettings, &QAction::triggered,
                     this, &MainWindow::onSaveSettings);

    QObject::connect(ui->actionLoadSettings, &QAction::triggered,
                     this, &MainWindow::onLoadSettings);

    ui->actionQuit->setShortcutContext(Qt::ApplicationShortcut);

    QObject::connect(ui->actionQuit, &QAction::triggered,
                     this, &MainWindow::close);

    // port control signals
    QObject::connect(&portControl, &PortControl::portToggled,
                     this, &MainWindow::onPortToggled);

    connect(&plotControlPanel, &PlotControlPanel::numOfSamplesChanged,
            this, &MainWindow::onNumOfSamplesChanged);

    connect(&plotControlPanel, &PlotControlPanel::numOfSamplesChanged,
            plotMan, &PlotManager::onNumOfSamplesChanged);

    connect(&plotControlPanel, &PlotControlPanel::scaleChanged,
            plotMan, &PlotManager::setAxis);

    QObject::connect(ui->actionClear, SIGNAL(triggered(bool)),
                     this, SLOT(clearPlot()));

    QObject::connect(snapshotMan.takeSnapshotAction(), &QAction::triggered,
                     plotMan, &PlotManager::flashSnapshotOverlay);

    // init port signals
    QObject::connect(&(this->serialPort), SIGNAL(error(QSerialPort::SerialPortError)),
                     this, SLOT(onPortError(QSerialPort::SerialPortError)));

    // init data format and reader
    QObject::connect(&dataFormatPanel, &DataFormatPanel::dataAdded,
                     plotMan, &PlotManager::replot);

    QObject::connect(ui->actionPause, &QAction::triggered,
                     &dataFormatPanel, &DataFormatPanel::pause);

    // init data arrays and plot
    numOfSamples = plotControlPanel.numOfSamples();
    unsigned numOfChannels = dataFormatPanel.numOfChannels();

    channelMan.setNumOfSamples(numOfSamples);
    channelMan.setNumOfChannels(dataFormatPanel.numOfChannels());

    connect(&dataFormatPanel, &DataFormatPanel::numOfChannelsChanged,
            &channelMan, &ChannelManager::setNumOfChannels);

    connect(&channelMan, &ChannelManager::numOfChannelsChanged,
            this, &MainWindow::onNumOfChannelsChanged);

    connect(&channelMan, &ChannelManager::channelNameChanged,
            this, &MainWindow::onChannelNameChanged);

    plotControlPanel.setChannelInfoModel(channelMan.infoModel());

    // init curve list
    for (unsigned int i = 0; i < numOfChannels; i++)
    {
        plotMan->addCurve(channelMan.channelName(i), channelMan.channelBuffer(i));
    }

    // init auto scale
    plotMan->setAxis(plotControlPanel.autoScale(),
                     plotControlPanel.yMin(), plotControlPanel.yMax());

    // Init sps (sample per second) counter
    spsLabel.setText("0sps");
    spsLabel.setToolTip("samples per second (per channel)");
    ui->statusBar->addPermanentWidget(&spsLabel);
    QObject::connect(&dataFormatPanel,
                     &DataFormatPanel::samplesPerSecondChanged,
                     this, &MainWindow::onSpsChanged);

    // init demo
    QObject::connect(ui->actionDemoMode, &QAction::toggled,
                     this, &MainWindow::enableDemo);

    QObject::connect(ui->actionDemoMode, &QAction::toggled,
                     plotMan, &PlotManager::showDemoIndicator);

    // load default settings
    QSettings settings("serialplot", "serialplot");
    loadAllSettings(&settings);

    // ensure command panel has 1 command if none loaded
    if (!commandPanel.numOfCommands())
    {
        commandPanel.newCommandAction()->trigger();
    }

    // Important: This should be after newCommandAction is triggered
    // (above) we don't want user to be greeted with command panel on
    // the very first run.
    connect(commandPanel.newCommandAction(), &QAction::triggered, [this]()
            {
                this->ui->tabWidget->setCurrentWidget(&commandPanel);
            });
}

MainWindow::~MainWindow()
{
    // save settings
    QSettings settings("serialplot", "serialplot");
    saveAllSettings(&settings);

    if (serialPort.isOpen())
    {
        serialPort.close();
    }

    delete plotMan;

    delete ui;
    ui = NULL; // we check if ui is deleted in messageHandler
}

void MainWindow::closeEvent(QCloseEvent * event)
{
    if (!snapshotMan.isAllSaved())
    {
        auto clickedButton = QMessageBox::warning(
            this, "Closing SerialPlot",
            "There are un-saved snapshots. If you close you will loose the data.",
            QMessageBox::Discard | QMessageBox::Discard,
            QMessageBox::Cancel);
        if (clickedButton == QMessageBox::Cancel)
        {
            event->ignore();
            return;
        }
    }
    QMainWindow::closeEvent(event);
}

void MainWindow::setupAboutDialog()
{
    Ui_AboutDialog uiAboutDialog;
    uiAboutDialog.setupUi(&aboutDialog);

    QObject::connect(uiAboutDialog.pbAboutQt, &QPushButton::clicked,
                     [](){ QApplication::aboutQt();});

    QString aboutText = uiAboutDialog.lbAbout->text();
    aboutText.replace("$VERSION_STRING$", VERSION_STRING);
    aboutText.replace("$VERSION_REVISION$", VERSION_REVISION);
    uiAboutDialog.lbAbout->setText(aboutText);
}

void MainWindow::onPortToggled(bool open)
{
    // make sure demo mode is disabled
    if (open && isDemoRunning()) enableDemo(false);
    ui->actionDemoMode->setEnabled(!open);
}

void MainWindow::onPortError(QSerialPort::SerialPortError error)
{
    switch(error)
    {
        case QSerialPort::NoError :
            break;
        case QSerialPort::ResourceError :
            qWarning() << "Port error: resource unavaliable; most likely device removed.";
            if (serialPort.isOpen())
            {
                qWarning() << "Closing port on resource error: " << serialPort.portName();
                portControl.togglePort();
            }
            portControl.loadPortList();
            break;
        case QSerialPort::DeviceNotFoundError:
            qCritical() << "Device doesn't exists: " << serialPort.portName();
            break;
        case QSerialPort::PermissionError:
            qCritical() << "Permission denied. Either you don't have \
required privileges or device is already opened by another process.";
            break;
        case QSerialPort::OpenError:
            qWarning() << "Device is already opened!";
            break;
        case QSerialPort::NotOpenError:
            qCritical() << "Device is not open!";
            break;
        case QSerialPort::ParityError:
            qCritical() << "Parity error detected.";
            break;
        case QSerialPort::FramingError:
            qCritical() << "Framing error detected.";
            break;
        case QSerialPort::BreakConditionError:
            qCritical() << "Break condition is detected.";
            break;
        case QSerialPort::WriteError:
            qCritical() << "An error occurred while writing data.";
            break;
        case QSerialPort::ReadError:
            qCritical() << "An error occurred while reading data.";
            break;
        case QSerialPort::UnsupportedOperationError:
            qCritical() << "Operation is not supported.";
            break;
        case QSerialPort::TimeoutError:
            qCritical() << "A timeout error occurred.";
            break;
        case QSerialPort::UnknownError:
            qCritical() << "Unknown error! Error: " << serialPort.errorString();
            break;
        default:
            qCritical() << "Unhandled port error: " << error;
            break;
    }
}

void MainWindow::clearPlot()
{
    for (unsigned ci = 0; ci < channelMan.numOfChannels(); ci++)
    {
        channelMan.channelBuffer(ci)->clear();
    }
    plotMan->replot();
}

void MainWindow::onNumOfSamplesChanged(int value)
{
    numOfSamples = value;
    channelMan.setNumOfSamples(value);
    plotMan->replot();
}

void MainWindow::onNumOfChannelsChanged(unsigned value)
{
    unsigned int oldNum = plotMan->numOfCurves();
    unsigned numOfChannels = value;

    if (numOfChannels > oldNum)
    {
        // add new channels
        for (unsigned int i = oldNum; i < numOfChannels; i++)
        {
            plotMan->addCurve(channelMan.channelName(i), channelMan.channelBuffer(i));
        }
    }
    else if(numOfChannels < oldNum)
    {
        plotMan->removeCurves(oldNum - numOfChannels);
    }

    plotMan->replot();
}

void MainWindow::onChannelNameChanged(unsigned channel, QString name)
{
    // This slot is triggered also when a new channel is added, in
    // this case curve list doesn't contain said channel. No worries,
    // since `onNumOfChannelsChanged` slot will update curve list.
    if (channel < plotMan->numOfCurves()) // check if channel exists in curve list
    {
        // plotMan->setTitle(channel, name);
    }
}

void MainWindow::onSpsChanged(unsigned sps)
{
    spsLabel.setText(QString::number(sps) + "sps");
}

bool MainWindow::isDemoRunning()
{
    return ui->actionDemoMode->isChecked();
}

void MainWindow::enableDemo(bool enabled)
{
    if (enabled)
    {
        if (!serialPort.isOpen())
        {
            dataFormatPanel.enableDemo(true);
        }
        else
        {
            ui->actionDemoMode->setChecked(false);
        }
    }
    else
    {
        dataFormatPanel.enableDemo(false);
        ui->actionDemoMode->setChecked(false);
    }
}

void MainWindow::onExportCsv()
{
    bool wasPaused = ui->actionPause->isChecked();
    ui->actionPause->setChecked(true); // pause plotting

    QString fileName = QFileDialog::getSaveFileName(this, tr("Export CSV File"));

    if (fileName.isNull())  // user canceled export
    {
        ui->actionPause->setChecked(wasPaused);
    }
    else
    {
        Snapshot* snapshot = snapshotMan.makeSnapshot();
        snapshot->save(fileName);
        delete snapshot;
    }
}

void MainWindow::messageHandler(QtMsgType type,
                                const QMessageLogContext &context,
                                const QString &msg)
{
    QString logString;

    switch (type)
    {
#if (QT_VERSION >= QT_VERSION_CHECK(5, 5, 0))
        case QtInfoMsg:
            logString = "[Info] " + msg;
            break;
#endif
        case QtDebugMsg:
            logString = "[Debug] " + msg;
            break;
        case QtWarningMsg:
            logString = "[Warning] " + msg;
            break;
        case QtCriticalMsg:
            logString = "[Error] " + msg;
            break;
        case QtFatalMsg:
            logString = "[Fatal] " + msg;
            break;
    }

    if (ui != NULL) ui->ptLog->appendPlainText(logString);
    std::cerr << logString.toStdString() << std::endl;

    if (type != QtDebugMsg && ui != NULL)
    {
        ui->statusBar->showMessage(msg, 5000);
    }

    if (type == QtFatalMsg)
    {
        __builtin_trap();
    }
}

void MainWindow::saveAllSettings(QSettings* settings)
{
    saveMWSettings(settings);
    portControl.saveSettings(settings);
    dataFormatPanel.saveSettings(settings);
    channelMan.saveSettings(settings);
    plotControlPanel.saveSettings(settings);
    plotMan->saveSettings(settings);
    commandPanel.saveSettings(settings);
}

void MainWindow::loadAllSettings(QSettings* settings)
{
    loadMWSettings(settings);
    portControl.loadSettings(settings);
    dataFormatPanel.loadSettings(settings);
    channelMan.loadSettings(settings);
    plotControlPanel.loadSettings(settings);
    plotMan->loadSettings(settings);
    commandPanel.loadSettings(settings);
}

void MainWindow::saveMWSettings(QSettings* settings)
{
    // save window geometry
    settings->beginGroup(SettingGroup_MainWindow);
    settings->setValue(SG_MainWindow_Size, size());
    settings->setValue(SG_MainWindow_Pos, pos());
    // save active panel
    settings->setValue(SG_MainWindow_ActivePanel,
                       panelSettingMap.value(ui->tabWidget->currentIndex()));
    // save panel minimization
    settings->setValue(SG_MainWindow_HidePanels,
                       ui->tabWidget->hideAction.isChecked());
    // save window maximized state
    settings->setValue(SG_MainWindow_Maximized,
                       bool(windowState() & Qt::WindowMaximized));
    // save toolbar/dockwidgets state
    settings->setValue(SG_MainWindow_State, saveState());
    settings->endGroup();
}

void MainWindow::loadMWSettings(QSettings* settings)
{
    settings->beginGroup(SettingGroup_MainWindow);
    // load window geometry
    resize(settings->value(SG_MainWindow_Size, size()).toSize());
    move(settings->value(SG_MainWindow_Pos, pos()).toPoint());

    // set active panel
    QString tabSetting =
        settings->value(SG_MainWindow_ActivePanel, QString()).toString();
    ui->tabWidget->setCurrentIndex(
        panelSettingMap.key(tabSetting, ui->tabWidget->currentIndex()));

    // hide panels
    ui->tabWidget->hideAction.setChecked(
        settings->value(SG_MainWindow_HidePanels,
                        ui->tabWidget->hideAction.isChecked()).toBool());

    // maximize window
    if (settings->value(SG_MainWindow_Maximized).toBool())
    {
        showMaximized();
    }

    // load toolbar/dockwidgets state
    restoreState(settings->value(SG_MainWindow_State).toByteArray());
    settings->setValue(SG_MainWindow_State, saveState());

    settings->endGroup();
}

void MainWindow::onSaveSettings()
{
    QString fileName = QFileDialog::getSaveFileName(
        this, tr("Save Settings"), QString(), "INI (*.ini)");

    if (!fileName.isNull()) // user canceled
    {
        QSettings settings(fileName, QSettings::IniFormat);
        saveAllSettings(&settings);
    }
}

void MainWindow::onLoadSettings()
{
    QString fileName = QFileDialog::getOpenFileName(
        this, tr("Load Settings"), QString(), "INI (*.ini)");

    if (!fileName.isNull()) // user canceled
    {
        QSettings settings(fileName, QSettings::IniFormat);
        loadAllSettings(&settings);
    }
}