cinema-ticket-management-system/ui/widgets/ticket_sales_report_widget.h

#ifndef TICKET_SALES_REPORT_WIDGET_H
#define TICKET_SALES_REPORT_WIDGET_H

#include "ui_ticket_sales_report_widget.h"

#include <QChartView>
#include <QLineSeries>
#include <QScatterSeries>
#include <functional>

// Forward declaration
class RepositoryResult;
class SessionStatisticsDTO;
class RepositoriesInterface;
class SessionsStatisticsRepository;

class TicketSalesReportWidget : public QWidget,
                                private Ui::TicketSalesReportWidget {
  Q_OBJECT

private:
  class SalesData {
  private:
    double refundExpenses_;
    double salesRevenue_;
    qint32 refundedTickets_;
    qint32 soldTickets_;
    qint32 maximumTickets_;

  public:
    SalesData();
    explicit SalesData(double refundExpenses, double salesRevenue,
                       qint32 refundedTickets, qint32 soldTickets,
                       qint32 maximumTickets);

    SalesData &operator+=(const SalesData &other);
    SalesData operator+(const SalesData &other) const;

    // clang-format off
    inline double refundExpenses() const { return refundExpenses_; };
    inline double salesRevenue() const { return salesRevenue_; };
    inline qint32 refundedTickets() const { return refundedTickets_; };
    inline qint32 soldTickets() const { return soldTickets_; };
    inline qint32 maximumTickets() const { return maximumTickets_; };
    inline void setRefundExpenses(double refundExpenses) { refundExpenses_ = refundExpenses; };
    inline void setRefundedTickets(qint32 refundedTickets) { refundedTickets_ = refundedTickets; };
    inline void setSalesRevenue(double salesRevenue) { salesRevenue_ = salesRevenue; };
    inline void setSoldTickets(qint32 soldTickets) { soldTickets_ = soldTickets; };
    inline void setMaximumTickets(qint32 maximumTickets) { maximumTickets_ = maximumTickets; };
    // clang-format on
  };

private:
  using GetSessionsForEntityByIdMethod = std::function<RepositoryResult(
      qint32 entityId, std::optional<QDateTime> startDate,
      std::optional<QDateTime> endDate,
      QVector<SessionStatisticsDTO> &sessions)>;

private:
  GetSessionsForEntityByIdMethod sessionsStatisticsMethod_;
  QChartView *chartView_;
  QDateTime startRange_, endRange_;
  QString billetChartTitle_, chartTitle_, seriesName_, yAxisTitle_;
  SessionsStatisticsRepository *sessionsStatisticsRepository;
  int columnInfoIndex_;
  qint32 selectedEntityId_;

public:
  explicit TicketSalesReportWidget(QWidget *parent = nullptr);

  void configureReportForGenre();
  void configureReportForHall();
  void configureReportForMovie();

private:
  void initializeChart();
  void initializeRepositories();
  void setupChart();
  void setupConnections();

  void configureEntityFinder(const QString &databaseTableName,
                             const QString &labelText,
                             const QString &placeholder);

private slots:
  void onEntityFinderReseted();
  void onPushButtonGenerateClicked();
  void onFieldRetrieved(const QSqlField &field);
  void onRecordRetrieved(const QSqlRecord &rowValues);

private:
  template <typename T, typename SeriesType>
  SeriesType *
  createSeriesTemplate(const QMap<QDateTime, SalesData> &accumulatedSalesData,
                       QDateTime &minDate, QDateTime &maxDate,
                       T (SalesData::*getter)() const,
                       const QString &seriesName);

  template <typename T>
  QAbstractSeries *
  createLineSeries(const QMap<QDateTime, SalesData> &accumulatedSalesData,
                   QDateTime &minDate, QDateTime &maxDate,
                   T (SalesData::*getter)() const, const QString &seriesName);

  template <typename T>
  QAbstractSeries *
  createScatterSeries(const QMap<QDateTime, SalesData> &accumulatedSalesData,
                      QDateTime &minDate, QDateTime &maxDate,
                      T (SalesData::*getter)() const,
                      const QString &seriesName);

  template <typename T>
  T maxValue(const QMap<QDateTime, SalesData> &data,
             T (SalesData::*getter)() const);

private:
  QMap<QDateTime, TicketSalesReportWidget::SalesData> aggregateByDateTime(
      const QVector<SessionStatisticsDTO> &sessions,
      std::function<bool(const SessionStatisticsDTO &)> filter = {});

  QAbstractAxis *createDateTimeAxis(int tickCount, const QString &axisTitle,
                                    const QDateTime &minDate,
                                    const QDateTime &maxDate) const;

  QAbstractAxis *createValueAxis(int maxValue, const QString &axisTitle) const;

  RepositoryResult retrieveSessions(QVector<SessionStatisticsDTO> &sessions);

  bool dateRange(QDateTime &startOut, QDateTime &endOut);

  bool validateData(const QMap<QDateTime, SalesData> &data) const;

  void createChart(const QMap<QDateTime, SalesData> &data);

  void setupChart(QChart *chart, QAbstractSeries *series, QAbstractAxis *axisX,
                  QAbstractAxis *axisY) const;

  void updateChartView(QChart *chart) const;
};

template <typename T, typename SeriesType>
SeriesType *TicketSalesReportWidget::createSeriesTemplate(
    const QMap<QDateTime, SalesData> &accumulatedSalesData, QDateTime &minDate,
    QDateTime &maxDate, T (SalesData::*getter)() const,
    const QString &seriesName) {

  auto *series = new SeriesType();
  series->setName(seriesName);

  bool first = true;

  for (auto it = accumulatedSalesData.cbegin();
       it != accumulatedSalesData.cend(); ++it) {
    const QDateTime &dateTime = it.key();

    series->append(dateTime.toMSecsSinceEpoch(), (it.value().*getter)());

    if (first) {
      minDate = dateTime;
      maxDate = dateTime;
      first = false;
    } else {
      if (dateTime < minDate)
        minDate = dateTime;
      if (dateTime > maxDate)
        maxDate = dateTime;
    }
  }

  return series;
}

template <typename T>
QAbstractSeries *TicketSalesReportWidget::createScatterSeries(
    const QMap<QDateTime, SalesData> &accumulatedSalesData, QDateTime &minDate,
    QDateTime &maxDate, T (SalesData::*getter)() const,
    const QString &seriesName) {

  return createSeriesTemplate<T, QScatterSeries>(accumulatedSalesData, minDate,
                                                 maxDate, getter, seriesName);
}

template <typename T>
QAbstractSeries *TicketSalesReportWidget::createLineSeries(
    const QMap<QDateTime, SalesData> &accumulatedSalesData, QDateTime &minDate,
    QDateTime &maxDate, T (SalesData::*getter)() const,
    const QString &seriesName) {

  return createSeriesTemplate<T, QLineSeries>(accumulatedSalesData, minDate,
                                              maxDate, getter, seriesName);
}

template <typename T>
T TicketSalesReportWidget::maxValue(const QMap<QDateTime, SalesData> &data,
                                    T (SalesData::*getter)() const) {
  if (data.isEmpty()) {
    return T{};
  }

  T maxValue = (data.cbegin().value().*getter)();

  for (auto it = data.cbegin(); it != data.cend(); ++it) {
    maxValue = std::max(maxValue, (it.value().*getter)());
  }

  return maxValue;
}

#endif // TICKET_SALES_REPORT_WIDGET_H