/*
    Copyright (C) 2016 Volker Krause <vkrause@kde.org>

    Permission is hereby granted, free of charge, to any person obtaining
    a copy of this software and associated documentation files (the
    "Software"), to deal in the Software without restriction, including
    without limitation the rights to use, copy, modify, merge, publish,
    distribute, sublicense, and/or sell copies of the Software, and to
    permit persons to whom the Software is furnished to do so, subject to
    the following conditions:

    The above copyright notice and this permission notice shall be included
    in all copies or substantial portions of the Software.

    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
    EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
    MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
    IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
    CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
    TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
    SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/

#include "analyticsview.h"
#include "ui_analyticsview.h"

#include "aggregator.h"
#include "categoryaggregator.h"
#include "chartexportdialog.h"
#include "chartutil.h"
#include "numericaggregator.h"
#include "ratiosetaggregator.h"
#include "totalaggregator.h"

#include <model/aggregateddatamodel.h>
#include <model/datamodel.h>
#include <model/timeaggregationmodel.h>
#include <rest/restapi.h>
#include <core/aggregation.h>
#include <core/sample.h>

#include <QtCharts/QChart>

#include <QClipboard>
#include <QFile>
#include <QFileDialog>
#include <QImage>
#include <QMenu>
#include <QMessageBox>
#include <QNetworkReply>
#include <QPdfWriter>
#include <QSettings>
#include <QSvgGenerator>

using namespace KUserFeedback::Console;

AnalyticsView::AnalyticsView(QWidget* parent) :
    QWidget(parent),
    ui(new Ui::AnalyticsView),
    m_dataModel(new DataModel(this)),
    m_timeAggregationModel(new TimeAggregationModel(this)),
    m_aggregatedDataModel(new AggregatedDataModel(this)),
    m_nullSingularChart(new QtCharts::QChart),
    m_nullTimelineChart(new QtCharts::QChart)
{
    ui->setupUi(this);

    ChartUtil::applyTheme(m_nullSingularChart.get());
    ChartUtil::applyTheme(m_nullTimelineChart.get());
    ui->singularChartView->setChart(m_nullSingularChart.get());
    ui->timelineChartView->setChart(m_nullTimelineChart.get());

    ui->dataView->setModel(m_dataModel);
    ui->aggregatedDataView->setModel(m_aggregatedDataModel);

    m_timeAggregationModel->setSourceModel(m_dataModel);
    connect(m_timeAggregationModel, &QAbstractItemModel::modelReset, this, &AnalyticsView::updateTimeSliderRange);

    ui->actionAggregateYear->setData(TimeAggregationModel::AggregateYear);
    ui->actionAggregateMonth->setData(TimeAggregationModel::AggregateMonth);
    ui->actionAggregateWeek->setData(TimeAggregationModel::AggregateWeek);
    ui->actionAggregateDay->setData(TimeAggregationModel::AggregateDay);
    auto aggrGroup = new QActionGroup(this);
    aggrGroup->addAction(ui->actionAggregateYear);
    aggrGroup->addAction(ui->actionAggregateMonth);
    aggrGroup->addAction(ui->actionAggregateWeek);
    aggrGroup->addAction(ui->actionAggregateDay);
    aggrGroup->setExclusive(true);
    connect(aggrGroup, &QActionGroup::triggered, this, [this, aggrGroup]() {
        m_timeAggregationModel->setAggregationMode(static_cast<TimeAggregationModel::AggregationMode>(aggrGroup->checkedAction()->data().toInt()));
    });

    auto timeAggrMenu = new QMenu(tr("&Time Interval"), this);
    timeAggrMenu->addAction(ui->actionAggregateDay);
    timeAggrMenu->addAction(ui->actionAggregateWeek);
    timeAggrMenu->addAction(ui->actionAggregateMonth);
    timeAggrMenu->addAction(ui->actionAggregateYear);

    auto chartModeGroup = new QActionGroup(this);
    chartModeGroup->addAction(ui->actionSingularChart);
    chartModeGroup->addAction(ui->actionTimelineChart);
    connect(chartModeGroup, &QActionGroup::triggered, this, &AnalyticsView::updateChart);

    auto chartMode = new QMenu(tr("&Chart Mode"), this);
    chartMode->addAction(ui->actionSingularChart);
    chartMode->addAction(ui->actionTimelineChart);

    ui->actionReload->setShortcut(QKeySequence::Refresh);
    connect(ui->actionReload, &QAction::triggered, m_dataModel, &DataModel::reload);
    connect(ui->actionExportChart, &QAction::triggered, this, &AnalyticsView::exportChart);
    connect(ui->actionExportData, &QAction::triggered, this, &AnalyticsView::exportData);
    connect(ui->actionImportData, &QAction::triggered, this, &AnalyticsView::importData);

    addActions({
        timeAggrMenu->menuAction(),
        chartMode->menuAction(),
        ui->actionReload,
        ui->actionExportChart,
        ui->actionExportData,
        ui->actionImportData
    });

    QSettings settings;
    settings.beginGroup(QStringLiteral("Analytics"));
    const auto aggrSetting = settings.value(QStringLiteral("TimeAggregationMode"), TimeAggregationModel::AggregateMonth).toInt();
    foreach (auto act, aggrGroup->actions())
        act->setChecked(act->data().toInt() == aggrSetting);
    m_timeAggregationModel->setAggregationMode(static_cast<TimeAggregationModel::AggregationMode>(aggrSetting));
    settings.endGroup();

    connect(ui->chartType, QOverload<int>::of(&QComboBox::currentIndexChanged), this, &AnalyticsView::chartSelected);
    connect(ui->timeSlider, &QSlider::valueChanged, this, [this](int value) {
        auto aggr = ui->chartType->currentData().value<Aggregator*>();
        if (!aggr)
            return;
        aggr->setSingularTime(value);
        ui->timeLabel->setText(aggr->singularAggregationModel()->index(0, 0).data(TimeAggregationModel::TimeDisplayRole).toString());
    });

    connect(ui->dataView, &QWidget::customContextMenuRequested, this, [this](QPoint pos) {
        QMenu menu;
        menu.addAction(QIcon::fromTheme(QStringLiteral("edit-copy")), tr("Copy"), [this, pos]() {
            const auto idx = ui->dataView->indexAt(pos);
            QGuiApplication::clipboard()->setText(idx.data().toString());
        });
        menu.exec(ui->dataView->viewport()->mapToGlobal(pos));
    });
}

AnalyticsView::~AnalyticsView()
{
    QSettings settings;
    settings.beginGroup(QStringLiteral("Analytics"));
    settings.setValue(QStringLiteral("TimeAggregationMode"), m_timeAggregationModel->aggregationMode());
    settings.endGroup();

    // the chart views can't handle null or deleted charts, so set them to something safe
    ui->singularChartView->setChart(m_nullSingularChart.get());
    ui->timelineChartView->setChart(m_nullTimelineChart.get());
    qDeleteAll(m_aggregators);
}

void AnalyticsView::setRESTClient(RESTClient* client)
{
    m_client = client;
    m_dataModel->setRESTClient(client);
}

void AnalyticsView::setProduct(const Product& product)
{
    // the chart views can't handle null or deleted charts, so set them to something safe
    ui->singularChartView->setChart(m_nullSingularChart.get());
    ui->timelineChartView->setChart(m_nullTimelineChart.get());

    m_dataModel->setProduct(product);

    ui->chartType->clear();
    m_aggregatedDataModel->clear();

    qDeleteAll(m_aggregators);
    m_aggregators.clear();

    m_aggregatedDataModel->addSourceModel(m_timeAggregationModel);
    auto totalsAggr = new TotalAggregator;
    m_aggregators.push_back(totalsAggr);
    totalsAggr->setSourceModel(m_timeAggregationModel);
    ui->chartType->addItem(totalsAggr->displayName(), QVariant::fromValue<Aggregator*>(totalsAggr));

    foreach (const auto &aggr, product.aggregations()) {
        auto aggregator = createAggregator(aggr);
        if (!aggregator)
            continue;
        m_aggregators.push_back(aggregator);
        if (auto model = aggregator->timeAggregationModel()) {
            m_aggregatedDataModel->addSourceModel(model, aggregator->displayName());
        }
        if (aggregator->chartModes() != Aggregator::None)
            ui->chartType->addItem(aggregator->displayName(), QVariant::fromValue(aggregator));
    }
}

void AnalyticsView::chartSelected()
{
    auto aggr = ui->chartType->currentData().value<Aggregator*>();
    if (!aggr)
        return;

    const auto chartMode = aggr->chartModes();
    ui->actionSingularChart->setEnabled(chartMode & Aggregator::Singular);
    ui->actionTimelineChart->setEnabled(chartMode & Aggregator::Timeline);
    if (chartMode != (Aggregator::Timeline | Aggregator::Singular)) {
        ui->actionSingularChart->setChecked(chartMode & Aggregator::Singular);
        ui->actionTimelineChart->setChecked(chartMode & Aggregator::Timeline);
    }

    updateChart();
}

void AnalyticsView::updateChart()
{
    auto aggr = ui->chartType->currentData().value<Aggregator*>();
    if (!aggr)
        return;

    if (ui->actionTimelineChart->isChecked()) {
        ui->timelineChartView->setChart(aggr->timelineChart());
        ui->chartStack->setCurrentWidget(ui->timelinePage);
    } else if (ui->actionSingularChart->isChecked()) {
        ui->singularChartView->setChart(aggr->singlularChart());
        ui->chartStack->setCurrentWidget(ui->singularPage);
        aggr->setSingularTime(ui->timeSlider->value());
    }
}

void AnalyticsView::updateTimeSliderRange()
{
    if (m_timeAggregationModel->rowCount() > 0) {
        ui->timeSlider->setRange(0, m_timeAggregationModel->rowCount() - 1);
        ui->timeLabel->setText(m_timeAggregationModel->index(ui->timeSlider->value(), 0).data(TimeAggregationModel::TimeDisplayRole).toString());
        auto aggr = ui->chartType->currentData().value<Aggregator*>();
        if (aggr)
            aggr->setSingularTime(ui->timeSlider->value());
    }
}

Aggregator* AnalyticsView::createAggregator(const Aggregation& aggr) const
{
    Aggregator *aggregator = nullptr;

    switch (aggr.type()) {
        case Aggregation::None:
            break;
        case Aggregation::Category:
            aggregator = new CategoryAggregator;
            break;
        case Aggregation::Numeric:
            aggregator = new NumericAggregator;
            break;
        case Aggregation::RatioSet:
            aggregator = new RatioSetAggregator;
            break;
    }

    if (!aggregator)
        return nullptr;

    aggregator->setAggregation(aggr);
    aggregator->setSourceModel(m_timeAggregationModel);
    return aggregator;
}

void AnalyticsView::exportData()
{
    const auto fileName = QFileDialog::getSaveFileName(this, tr("Export Data"));
    if (fileName.isEmpty())
        return;

    QFile f(fileName);
    if (!f.open(QFile::WriteOnly)) {
        QMessageBox::critical(this, tr("Export Failed"), tr("Could not open file: %1").arg(f.errorString()));
        return;
    }

    const auto samples = m_dataModel->index(0, 0).data(DataModel::AllSamplesRole).value<QVector<Sample>>();
    f.write(Sample::toJson(samples, m_dataModel->product()));
    emit logMessage(tr("Data samples of %1 exported to %2.").arg(m_dataModel->product().name(), f.fileName()));
}

void AnalyticsView::importData()
{
    const auto fileName = QFileDialog::getOpenFileName(this, tr("Import Data"));
    if (fileName.isEmpty())
        return;

    QFile f(fileName);
    if (!f.open(QFile::ReadOnly)) {
        QMessageBox::critical(this, tr("Import Failed"), tr("Could not open file: %1").arg(f.errorString()));
        return;
    }
    const auto samples = Sample::fromJson(f.readAll(), m_dataModel->product());
    if (samples.isEmpty()) {
        QMessageBox::critical(this, tr("Import Failed"), tr("Selected file contains no valid data."));
        return;
    }

    auto reply = RESTApi::addSamples(m_client, m_dataModel->product(), samples);
    connect(reply, &QNetworkReply::finished, this, [this, reply]() {
        if (reply->error() == QNetworkReply::NoError) {
            emit logMessage(tr("Data samples imported."));
            m_dataModel->reload();
        }
    });
}

void AnalyticsView::exportChart()
{
    ChartExportDialog dlg(this);
    if (dlg.exec() != QDialog::Accepted)
        return;

    QtCharts::QChart *chart = nullptr;
    QGraphicsScene *scene = nullptr;
    if (ui->actionTimelineChart->isChecked()) {
        chart = ui->timelineChartView->chart();
        scene = ui->timelineChartView->scene();
    } else if (ui->actionSingularChart->isChecked()) {
        chart = ui->singularChartView->chart();
        scene = ui->singularChartView->scene();
    }
    Q_ASSERT(chart);
    Q_ASSERT(scene);

    chart->setTheme(QtCharts::QChart::ChartThemeLight);

    switch (dlg.type()) {
        case ChartExportDialog::Image:
        {
            QImage img(dlg.size(), QImage::Format_ARGB32_Premultiplied);
            img.fill(Qt::transparent);
            QPainter p(&img);
            p.setRenderHint(QPainter::HighQualityAntialiasing);
            scene->render(&p, QRectF(QPoint(), dlg.size()), scene->sceneRect());
            img.save(dlg.filename());
            break;
        }
        case ChartExportDialog::SVG:
        {
            QSvgGenerator svg;
            svg.setFileName(dlg.filename());
            svg.setSize(scene->sceneRect().size().toSize());
            svg.setViewBox(scene->sceneRect());
            svg.setTitle(ui->chartType->currentText());

            QPainter p(&svg);
            p.setRenderHint(QPainter::HighQualityAntialiasing);
            scene->render(&p);
            break;
        }
        case ChartExportDialog::PDF:
        {
            QPdfWriter pdf(dlg.filename());
            pdf.setCreator(QStringLiteral("UserFeedbackConsole"));
            pdf.setTitle(ui->chartType->currentText());
            if (scene->sceneRect().width() > scene->sceneRect().height())
                pdf.setPageOrientation(QPageLayout::Landscape);

            QPainter p(&pdf);
            p.setRenderHint(QPainter::HighQualityAntialiasing);
            scene->render(&p);
            break;
        }
    }

    ChartUtil::applyTheme(chart);
}
