// Copyright (C) 2023 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause

#include "themewidget.h"
#include "ui_themewidget.h"

#include <QAbstractBarSeries>
#include <QAreaSeries>
#include <QBarSet>
#include <QChartView>
#include <QCheckBox>
#include <QComboBox>
#include <QGridLayout>
#include <QLegend>
#include <QLineSeries>
#include <QPercentBarSeries>
#include <QPieSeries>
#include <QPieSlice>
#include <QRandomGenerator>
#include <QScatterSeries>
#include <QSplineSeries>
#include <QStackedBarSeries>
#include <QValueAxis>

ThemeWidget::ThemeWidget(QWidget *parent) :
    ContentWidget(parent),
    m_listCount(3),
    m_valueMax(10),
    m_valueCount(7),
    m_dataTable(generateRandomData(m_listCount, m_valueMax, m_valueCount)),
    m_ui(new Ui_ThemeWidgetForm)
{
    m_ui->setupUi(this);
    populateThemeBox();
    populateAnimationBox();
    populateLegendBox();

    //create charts

    QChartView *chartView;

    chartView = new QChartView(createAreaChart(), this);
    m_ui->gridLayout->addWidget(chartView, 1, 0);
    m_charts << chartView;

    chartView = new QChartView(createPieChart(), this);
    // Funny things happen if the pie slice labels do not fit the screen, so we ignore size policy
    chartView->setSizePolicy(QSizePolicy::Ignored, QSizePolicy::Ignored);
    m_ui->gridLayout->addWidget(chartView, 1, 1);
    m_charts << chartView;

    //![5]
    chartView = new QChartView(createLineChart(), this);
    m_ui->gridLayout->addWidget(chartView, 1, 2);
    //![5]
    m_charts << chartView;

    chartView = new QChartView(createBarChart(m_valueCount), this);
    m_ui->gridLayout->addWidget(chartView, 2, 0);
    m_charts << chartView;

    chartView = new QChartView(createSplineChart(), this);
    m_ui->gridLayout->addWidget(chartView, 2, 1);
    m_charts << chartView;

    chartView = new QChartView(createScatterChart(), this);
    m_ui->gridLayout->addWidget(chartView, 2, 2);
    m_charts << chartView;

    // Set defaults
    m_ui->antialiasCheckBox->setChecked(true);

    updateUI();
}

ThemeWidget::~ThemeWidget()
{
    delete m_ui;
}

DataTable ThemeWidget::generateRandomData(int listCount, int valueMax, int valueCount) const
{
    DataTable dataTable;

    // generate random data
    for (int i(0); i < listCount; i++) {
        DataList dataList;
        qreal yValue(0);
        for (int j(0); j < valueCount; j++) {
            yValue = yValue + QRandomGenerator::global()->bounded(valueMax / (qreal) valueCount);
            QPointF value((j + QRandomGenerator::global()->generateDouble()) * ((qreal) m_valueMax / (qreal) valueCount),
                          yValue);
            QString label = "Slice " + QString::number(i) + ":" + QString::number(j);
            dataList << Data(value, label);
        }
        dataTable << dataList;
    }

    return dataTable;
}

void ThemeWidget::populateThemeBox()
{
    // add items to theme combobox
    m_ui->themeComboBox->addItem("Light", QChart::ChartThemeLight);
    m_ui->themeComboBox->addItem("Blue Cerulean", QChart::ChartThemeBlueCerulean);
    m_ui->themeComboBox->addItem("Dark", QChart::ChartThemeDark);
    m_ui->themeComboBox->addItem("Brown Sand", QChart::ChartThemeBrownSand);
    m_ui->themeComboBox->addItem("Blue NCS", QChart::ChartThemeBlueNcs);
    m_ui->themeComboBox->addItem("High Contrast", QChart::ChartThemeHighContrast);
    m_ui->themeComboBox->addItem("Blue Icy", QChart::ChartThemeBlueIcy);
    m_ui->themeComboBox->addItem("Qt", QChart::ChartThemeQt);
}

void ThemeWidget::populateAnimationBox()
{
    // add items to animation combobox
    m_ui->animatedComboBox->addItem("No Animations", QChart::NoAnimation);
    m_ui->animatedComboBox->addItem("GridAxis Animations", QChart::GridAxisAnimations);
    m_ui->animatedComboBox->addItem("Series Animations", QChart::SeriesAnimations);
    m_ui->animatedComboBox->addItem("All Animations", QChart::AllAnimations);
}

void ThemeWidget::populateLegendBox()
{
    // add items to legend combobox
    m_ui->legendComboBox->addItem("No Legend ", 0);
    m_ui->legendComboBox->addItem("Legend Top", Qt::AlignTop);
    m_ui->legendComboBox->addItem("Legend Bottom", Qt::AlignBottom);
    m_ui->legendComboBox->addItem("Legend Left", Qt::AlignLeft);
    m_ui->legendComboBox->addItem("Legend Right", Qt::AlignRight);
}

QChart *ThemeWidget::createAreaChart() const
{
    auto chart = new QChart;
    chart->setTitle("Area Chart");

    // The lower series initialized to zero values
    QLineSeries *lowerSeries = nullptr;
    QString name("Series ");
    int nameIndex = 0;
    for (int i(0); i < m_dataTable.count(); i++) {
        auto upperSeries = new QLineSeries(chart);
        for (int j(0); j < m_dataTable[i].count(); j++) {
            Data data = m_dataTable[i].at(j);
            if (lowerSeries) {
                const auto &points = lowerSeries->points();
                upperSeries->append(QPointF(j, points[i].y() + data.first.y()));
            } else {
                upperSeries->append(QPointF(j, data.first.y()));
            }
        }
        auto area = new QAreaSeries(upperSeries, lowerSeries);
        area->setName(name + QString::number(nameIndex));
        nameIndex++;
        chart->addSeries(area);
        lowerSeries = upperSeries;
    }

    chart->createDefaultAxes();
    chart->axes(Qt::Horizontal).first()->setRange(0, m_valueCount - 1);
    chart->axes(Qt::Vertical).first()->setRange(0, m_valueMax);
    // Add space to label to add space between labels and axis
    auto axisY = qobject_cast<QValueAxis *>(chart->axes(Qt::Vertical).first());
    Q_ASSERT(axisY);
    axisY->setLabelFormat("%.1f  ");

    return chart;
}

QChart *ThemeWidget::createBarChart(int valueCount) const
{
    Q_UNUSED(valueCount);
    auto chart = new QChart;
    chart->setTitle("Bar Chart");

    auto series = new QStackedBarSeries(chart);
    for (int i(0); i < m_dataTable.count(); i++) {
        auto set = new QBarSet("Bar set " + QString::number(i));
        for (const Data &data : m_dataTable[i])
            *set << data.first.y();
        series->append(set);
    }
    chart->addSeries(series);

    chart->createDefaultAxes();
    chart->axes(Qt::Vertical).first()->setRange(0, m_valueMax * 2);
    // Add space to label to add space between labels and axis
    auto axisY = qobject_cast<QValueAxis *>(chart->axes(Qt::Vertical).first());
    Q_ASSERT(axisY);
    axisY->setLabelFormat("%.1f  ");

    return chart;
}

QChart *ThemeWidget::createLineChart() const
{
    //![1]
    auto chart = new QChart;
    chart->setTitle("Line Chart");
    //![1]

    //![2]
    QString name("Series ");
    int nameIndex = 0;
    for (const DataList &list : m_dataTable) {
        auto series = new QLineSeries(chart);
        for (const Data &data : list)
            series->append(data.first);
        series->setName(name + QString::number(nameIndex));
        nameIndex++;
        chart->addSeries(series);
    }
    //![2]

    //![3]
    chart->createDefaultAxes();
    chart->axes(Qt::Horizontal).first()->setRange(0, m_valueMax);
    chart->axes(Qt::Vertical).first()->setRange(0, m_valueCount);
    //![3]
    //![4]
    // Add space to label to add space between labels and axis
    auto axisY = qobject_cast<QValueAxis *>(chart->axes(Qt::Vertical).first());
    Q_ASSERT(axisY);
    axisY->setLabelFormat("%.1f  ");
    //![4]

    return chart;
}

QChart *ThemeWidget::createPieChart() const
{
    auto chart = new QChart;
    chart->setTitle("Pie Chart");

    auto series = new QPieSeries(chart);
    for (const Data &data : m_dataTable[0]) {
        QPieSlice *slice = series->append(data.second, data.first.y());
        if (data == m_dataTable[0].first()) {
            // Show the first slice exploded with label
            slice->setLabelVisible();
            slice->setExploded();
            slice->setExplodeDistanceFactor(0.5);
        }
    }
    series->setPieSize(0.4);
    chart->addSeries(series);

    return chart;
}

QChart *ThemeWidget::createSplineChart() const
{
    auto chart = new QChart;
    chart->setTitle("Spline Chart");
    QString name("Series ");
    int nameIndex = 0;
    for (const DataList &list : m_dataTable) {
        auto series = new QSplineSeries(chart);
        for (const Data &data : list)
            series->append(data.first);
        series->setName(name + QString::number(nameIndex));
        nameIndex++;
        chart->addSeries(series);
    }

    chart->createDefaultAxes();
    chart->axes(Qt::Horizontal).first()->setRange(0, m_valueMax);
    chart->axes(Qt::Vertical).first()->setRange(0, m_valueCount);

    // Add space to label to add space between labels and axis
    auto axisY = qobject_cast<QValueAxis *>(chart->axes(Qt::Vertical).first());
    Q_ASSERT(axisY);
    axisY->setLabelFormat("%.1f  ");
    return chart;
}

QChart *ThemeWidget::createScatterChart() const
{
    // scatter chart
    auto chart = new QChart;
    chart->setTitle("Scatter Chart");
    QString name("Series ");
    int nameIndex = 0;
    for (const DataList &list : m_dataTable) {
        auto series = new QScatterSeries(chart);
        for (const Data &data : list)
            series->append(data.first);
        series->setName(name + QString::number(nameIndex));
        nameIndex++;
        chart->addSeries(series);
    }

    chart->createDefaultAxes();
    chart->axes(Qt::Horizontal).first()->setRange(0, m_valueMax);
    chart->axes(Qt::Vertical).first()->setRange(0, m_valueCount);
    // Add space to label to add space between labels and axis
    auto axisY = qobject_cast<QValueAxis *>(chart->axes(Qt::Vertical).first());
    Q_ASSERT(axisY);
    axisY->setLabelFormat("%.1f  ");
    return chart;
}

void ThemeWidget::updateUI()
{
    //![6]
    auto theme = static_cast<QChart::ChartTheme>(
                m_ui->themeComboBox->itemData(m_ui->themeComboBox->currentIndex()).toInt());
    //![6]
    const auto charts = m_charts;
    if (!m_charts.isEmpty() && m_charts.at(0)->chart()->theme() != theme) {
        for (QChartView *chartView : charts) {
            //![7]
            chartView->chart()->setTheme(theme);
            //![7]
        }
    }

    // Update antialiasing
    //![11]
    bool checked = m_ui->antialiasCheckBox->isChecked();
    for (QChartView *chart : charts)
        chart->setRenderHint(QPainter::Antialiasing, checked);
    //![11]

    // Update animation options
    //![9]
    QChart::AnimationOptions options(
                m_ui->animatedComboBox->itemData(m_ui->animatedComboBox->currentIndex()).toInt());
    if (!m_charts.isEmpty() && m_charts.at(0)->chart()->animationOptions() != options) {
        for (QChartView *chartView : charts)
            chartView->chart()->setAnimationOptions(options);
    }
    //![9]

    // Update legend alignment
    //![10]
    Qt::Alignment alignment(
                m_ui->legendComboBox->itemData(m_ui->legendComboBox->currentIndex()).toInt());

    if (!alignment) {
        for (QChartView *chartView : charts)
            chartView->chart()->legend()->hide();
    } else {
        for (QChartView *chartView : charts) {
            chartView->chart()->legend()->setAlignment(alignment);
            chartView->chart()->legend()->show();
        }
    }
    //![10]
}