cinema-ticket-management-system/core/services/refund_generator.cpp

#include "refund_generator.h"

#include "create_refund_request.h"
#include "refunds_repository.h"
#include "repository_manager.h"
#include "repository_result.h"
#include "schema_metadata.h"
#include "session_dto.h"
#include "sessions_repository.h"
#include "ticket_dto.h"
#include "tickets_repository.h"
#include <QRandomGenerator>

RefundGenerator::RefundGenerator(const QPair<double, double> &refundRatioRange,
                                 const QPair<qint64, qint64> &dayRange,
                                 const QPair<QTime, QTime> &timeRange)
    : BaseGenerator("Refund"), DateTimeGenerator(dayRange, timeRange),
      refundRatioRange_(refundRatioRange) {
  auto &[lowest, highest] = refundRatioRange_;
  if (lowest > highest) {
    qCritical() << "Lowest refund ratio is greater than the highest refund, "
                   "values will be swapped";
    std::swap(lowest, highest);
  }

  initializeRepositories();            // First
  initializeTicketIdToCacheValueMap(); // After initializing
                                       // repositories
  initializeRemainingCapacity(); // After initializing ticketIdToCacheValue
}

void RefundGenerator::initializeRepositories() {
  RepositoryManager &repositoryManager = RepositoryManager::instance();
  SchemaMetadata metadata = SchemaMetadata::defaultSchema();

  ticketsRepository_ = repositoryManager.getRepositoryAs<TicketsRepository>(
      metadata.repositoryTableName("tickets"));
  refundsRepository_ = repositoryManager.getRepositoryAs<RefundsRepository>(
      metadata.repositoryTableName("refunds"));
  sessionsRepository_ = repositoryManager.getRepositoryAs<SessionsRepository>(
      metadata.repositoryTableName("sessions"));

  if (!bool(ticketsRepository_ && refundsRepository_ && sessionsRepository_)) {
    qFatal() << "Failed to initialize repositories";
  }
}

void RefundGenerator::initializeTicketIdToCacheValueMap() {
  QVector<SessionDTO> sessions;
  RepositoryResult resultGetAllSessions =
      sessionsRepository_->getAllSessions(sessions);
  if (!resultGetAllSessions.success) {
    qFatal() << "Failed to retrieve sessions";
  }

  QMap<qint32 /* sessionId */,
       QPair<QDateTime /* beginAt */, double /* ticketPrice */>>
      sessionIdToBeginAtAndTicketPrice;

  for (const SessionDTO &session : sessions) {
    sessionIdToBeginAtAndTicketPrice[session.sessionId()] =
        qMakePair(session.beginAt(), session.ticketPrice());
  }

  QVector<TicketDTO> tickets;
  RepositoryResult resultGetAllTickets =
      ticketsRepository_->getAllTickets(tickets);

  if (!resultGetAllTickets.success) {
    qFatal() << "Failed to retrieve tickets";
  }

  for (const auto &ticket : tickets) {
    const auto &[beginAt, ticketPrice] =
        sessionIdToBeginAtAndTicketPrice[ticket.sessionId()];
    CacheValue cacheValue{beginAt, ticket.soldAt(), ticketPrice};

    if (calculateDurationMs(cacheValue) < 2) {
      continue;
    }

    ticketIdToCacheValue_[ticket.ticketId()] = cacheValue;
  }
}

QString
RefundGenerator::createFailureMessage(const QString &errorMessage) const {
  const QString dateTimeFormat = "yyyy-MM-dd hh:mm:ss.zzz";
  QString additionalInfo =
      QString("Additional info: Ticket id: %1 Refund amount: %2 Sold at: %3 "
              "Refund at: %4 Begin at: %5")
          .arg(reservationContext_.ticketId)
          .arg(reservationContext_.refundAmount)
          .arg(reservationContext_.soldAt.toString(dateTimeFormat))
          .arg(reservationContext_.refundAt.toString(dateTimeFormat))
          .arg(reservationContext_.beginAt.toString(dateTimeFormat));
  QString failureMessage = "Failure:\n\t%1\n\tError message: %2";
  return failureMessage.arg(additionalInfo).arg(errorMessage);
}

QString RefundGenerator::createSuccessMessage() const {
  return QString("Success: EId: %1 RAm: %2 RAt: %3")
      .arg(reservationContext_.ticketId)
      .arg(reservationContext_.refundAmount)
      .arg(reservationContext_.refundAt.toString("yyyy-MM-dd hh:mm:ss"));
}

qsizetype RefundGenerator::calculateRemainingCapacity() const {
  return remainingCapacity_;
}

RepositoryResult RefundGenerator::createRecord() {
  CreateRefundRequest request;
  request.setRefundAmount(reservationContext_.refundAmount);
  request.setRefundAt(reservationContext_.refundAt);
  request.setTicketId(reservationContext_.ticketId);

  RepositoryResult result = refundsRepository_->createRefund(request);

  if (result.success) {
    --remainingCapacity_;
  }

  return result;
}

bool RefundGenerator::prepareData() {
  if (ticketIdToCacheValue_.isEmpty()) {
    qInfo() << "No tickets to refund";
    return false;
  }

  qsizetype ticketIdIndex = bounded<qsizetype>(0, ticketIdToCacheValue_.size());
  auto ticketIdIt = ticketIdToCacheValue_.cbegin();
  std::advance(ticketIdIt, ticketIdIndex);

  qint32 ticketId = ticketIdIt.key();
  CacheValue cacheValue = ticketIdIt.value();

  constexpr qint32 fiveMinutesMs = 5 * 1000 * 60;
  qint64 deltaBoundMs = calculateDurationMs(cacheValue) / 2;
  if (deltaBoundMs > fiveMinutesMs) {
    deltaBoundMs = fiveMinutesMs;
  }

  const QDateTime refundAt =
      // SoldAt < RefundAt < BeginAt
      // SoldAt + n minute <= RefundAt <= BeginAt - n minute
      generate(cacheValue.soldAt.addMSecs(+deltaBoundMs),
               cacheValue.beginAt.addMSecs(-deltaBoundMs));

  const auto [refundRatioLowest, refundRatioHighest] = refundRatioRange_;
  int lowest = refundRatioLowest * 100;
  int highest = refundRatioHighest * 100;
  int numerator = bounded(lowest, highest);
  double refundAmount = std::floor(numerator * cacheValue.ticketPrice) / 100.0;

  ReservationContext context{cacheValue.beginAt, refundAt, cacheValue.soldAt,
                             refundAmount, ticketId};
  reservationContext_ = std::move(context);

  return true;
}

void RefundGenerator::clearStaleData() {
  qint32 ticketId = reservationContext_.ticketId;
  ticketIdToCacheValue_.remove(ticketId);
}