#include "calculator_functions.h"
#include "payment_option.h"
#include "utilities.h"
#include "tariff_log.h"
#include "tariff_time_range.h"

#include <sstream>
#include <algorithm>
#include <QDateTime>
#include <QScopedArrayPointer>
#include <QDebug>

double total_duration_min = 0.0f;
double total_cost = 0.0f;
bool overtime = false;

#ifdef _WIN32
inline struct tm* localtime_r(const time_t *clock, struct tm* result){
    if(!clock || !result) return NULL;
    memcpy(result,localtime(clock),sizeof(*result));
    return result;
}
#endif

QDateTime Calculator::GetDailyTicketDuration(Configuration* cfg, const QDateTime start_datetime, uint8_t payment_option, bool carry_over)
{
    if(!start_datetime.isValid()) {
        return QDateTime();
    }

    double day_price = 0.0f;
    int current_special_day_id = -1;
    bool is_special_day = Utilities::CheckSpecialDay(cfg, start_datetime.toString(Qt::ISODate).toStdString().c_str(), &current_special_day_id, &day_price);

    QDateTime inputDateTime = start_datetime;
    QTime worktime_from;
    QTime worktime_to;

    int daily_card_price = cfg->PaymentOption.find(payment_option)->second.pop_daily_card_price;
    if(daily_card_price <= 0) {
        LOG_ERROR("Calculator::GetDailyTicketDuration(): Daily ticket price zero or less");
        return QDateTime();
    }

    if(is_special_day)
    {
        worktime_from = QTime::fromString(cfg->SpecialDaysWorktime.find(current_special_day_id)->second.pedwt_time_from.c_str(), Qt::ISODate);
        worktime_to = QTime::fromString(cfg->SpecialDaysWorktime.find(current_special_day_id)->second.pedwt_time_to.c_str(),Qt::ISODate);

        if(inputDateTime.time() < worktime_from) inputDateTime.setTime(worktime_from);
        if(carry_over) inputDateTime.setTime(worktime_from);

        if(inputDateTime.time() >= worktime_to)
        {
            // Go to next day if outside worktime
            inputDateTime = inputDateTime.addSecs(86400);
            return GetDailyTicketDuration(cfg,inputDateTime, payment_option,true);
        }

        if(day_price <=0)
        {
            // Go to next day if special day price is 0
            inputDateTime = inputDateTime.addSecs(86400);
            return GetDailyTicketDuration(cfg,inputDateTime, payment_option,true);
        }

        int diff = abs(inputDateTime.time().secsTo(worktime_to));
        inputDateTime = inputDateTime.addSecs(diff);

        //qDebug() << "Ticket is valid until: " << inputDateTime.toString(Qt::ISODate) << "price = " << daily_card_price << ", duration = " << diff / 60;
        return inputDateTime;
    }
    else
    {
        // Get day of week
        int weekdayId = 0;
        weekdayId = Utilities::ZellersAlgorithm(inputDateTime.date().day(),inputDateTime.date().month(),inputDateTime.date().year());

        // If no working day found, skip it (recursively call method again)
        size_t found = 0;
        found = cfg->WeekDaysWorktime.count(weekdayId);

        // When no workday found, go to next available day
        if(found <=0)
        {
            inputDateTime = inputDateTime.addSecs(86400);
            return GetDailyTicketDuration(cfg,inputDateTime, payment_option,true);
        }
        else
        {
            worktime_from = QTime::fromString(cfg->WeekDaysWorktime.find(weekdayId)->second.pwd_time_from.c_str(),Qt::ISODate);
            worktime_to = QTime::fromString(cfg->WeekDaysWorktime.find(weekdayId)->second.pwd_time_to.c_str(),Qt::ISODate);
            if(inputDateTime.time() < worktime_from)
                inputDateTime.setTime(worktime_from);

            if(carry_over)
                inputDateTime.setTime(worktime_from);

            if(inputDateTime.time() >= worktime_to)
            {
                // Go to next day if outside worktime
                inputDateTime = inputDateTime.addSecs(86400);
                return GetDailyTicketDuration(cfg,inputDateTime, payment_option,true);
            }

            int diff = abs(inputDateTime.time().secsTo(worktime_to));
            inputDateTime = inputDateTime.addSecs(diff);

            //qDebug() << "Ticket is valid until: " << inputDateTime.toString(Qt::ISODate) << "price = " << daily_card_price << ", duration = " << diff / 60;            
            return inputDateTime;
        }
    }

    return QDateTime();
}
/// <inheritdoc/>
std::string Calculator::GetDurationFromCost(Configuration* cfg,
                                            uint8_t payment_option,
                                            char const* start_datetime, // given in local time
                                            double price,
                                            bool nextDay,
                                            bool prepaid)
{

    // Get input date
    QDateTime inputDate = QDateTime::fromString(start_datetime,Qt::ISODate);

    // use tariff with structure as for instance Schnau, Koenigsee:
    // without given YearPeriod, SpecialDays and SpecialDaysWorktime
    if (cfg->YearPeriod.size() == 0
        && cfg->SpecialDays.size() == 0
        && cfg->SpecialDaysWorktime.size() == 0)
    {
        inputDate = inputDate.addSecs(GetDurationForPrice(cfg, price) * 60);

        return inputDate.toString(Qt::ISODate).toStdString();
    }


    // Get day of week
    int weekdayId = 0;
    weekdayId = Utilities::ZellersAlgorithm(inputDate.date().day(),inputDate.date().month(),inputDate.date().year());

    //Get min and max time defined in JSON
    double minMin = 0;
    minMin = cfg->getPaymentOptions().pop_min_time;

    double maxMin = 0;
    maxMin = cfg->getPaymentOptions().pop_max_time;

    double min_price = 0;
    min_price = cfg->getPaymentOptions().pop_min_price;

    if(price < min_price)
    {
        return "PARKING NOT ALLOWED";
    }

    if (minMin < 0) minMin = 0;
    if (maxMin < 0) maxMin = 0;
    if (minMin >= maxMin)
    {
        LOG_ERROR("Error: min_min cannot be greater or equal to max_min");
        return "PARKING NOT ALLOWED";
    }

    if (maxMin <= minMin)
    {
        LOG_ERROR("Error: max_min cannot be lower or equal than min_min");
        return "PARKING NOT ALLOWED";
    }


    // Get payment method
    uint8_t p_method = PaymentMethod::Undefined;
    p_method = payment_option;
    LOG_DEBUG("Payment method id: ", (unsigned)p_method);

    // Check special day
    double day_price = 0.0f;
    int current_special_day_id = -1;
    bool is_special_day = Utilities::CheckSpecialDay(cfg, inputDate.toString(Qt::ISODate).toStdString().c_str(), &current_special_day_id, &day_price);
    LOG_DEBUG("Special day: ", is_special_day);

    double money_left = price;
    double price_per_unit = 0.0f;

    QTime worktime_from;
    QTime worktime_to;

    if(is_special_day)
    {
        // Set special day price
        price_per_unit = Utilities::CalculatePricePerUnit(day_price);
        worktime_from = QTime::fromString(cfg->SpecialDaysWorktime.find(current_special_day_id)->second.pedwt_time_from.c_str());
        worktime_to = QTime::fromString(cfg->SpecialDaysWorktime.find(current_special_day_id)->second.pedwt_time_to.c_str());
    }
    else
    {
        // Set new price for the normal day
        int pop_id = cfg->PaymentOption.find(payment_option)->second.pop_id;
        day_price = cfg->PaymentRate.find(pop_id)->second.pra_price;

        int durationId = cfg->PaymentRate.find(pop_id)->second.pra_payment_unit_id;
        double durationUnit = cfg->Duration.find(durationId)->second.pun_duration;
        price_per_unit = Utilities::CalculatePricePerUnit(day_price,durationUnit);

        // If no working day found, skip it (recursively call method again)
        size_t found = 0;
        found = cfg->WeekDaysWorktime.count(weekdayId);

        // When no workday found, go to next available day
        if(found <=0)
        {
            LOG_DEBUG("- No workday found, trying to find next available day");
            inputDate = inputDate.addDays(1);
            return GetDurationFromCost(cfg, payment_option, inputDate.toString(Qt::ISODate).toStdString().c_str(), money_left,true,prepaid);
        }
        worktime_from = QTime::fromString(cfg->WeekDaysWorktime.find(weekdayId)->second.pwd_time_from.c_str());
        worktime_to = QTime::fromString(cfg->WeekDaysWorktime.find(weekdayId)->second.pwd_time_to.c_str());
    }

    if (price_per_unit < 0) price_per_unit = 1.0f;

    // if((price/price_per_unit) < minMin) return "PARKING NOT ALLOWED";
    LOG_DEBUG("Calculated price per minute: ", price_per_unit);

    // If overtime flag is set
    if (overtime || nextDay)
    {
        inputDate.setTime(worktime_from);
        overtime = false;
    }

    // Check prepaid
    if (!prepaid)
    {
        if ((inputDate.time() < worktime_from) || (inputDate.time() > worktime_to))
        {
            LOG_DEBUG("[STOP] * Ticket is not valid * ");
            return "PARKING NOT ALLOWED";
        }
    }
    else
    {
        LOG_DEBUG("* PREPAID MODE ACTIVE *");
        if (inputDate.time() < worktime_from)
        {
            inputDate.setTime(worktime_from);
        }
        else if(inputDate.time() > worktime_to)
        {
            LOG_DEBUG(" *** PREPAID *** Current time is past the time range end, searching for next available day");
            inputDate = inputDate.addDays(1);
            return GetDurationFromCost(cfg, payment_option, inputDate.toString(Qt::ISODate).toStdString().c_str(), money_left, true);
        }
    }

    while(true)
    {
        if((int)money_left <= 0) break;

        // Check year period
        bool isYearPeriodActive = false;

        //// Parse input date
        int dayCurrent = inputDate.date().day();
        int monthCurrent = inputDate.date().month();

        // Current date time
        int cdt = (monthCurrent * 100) + dayCurrent;

        multimap<int, ATBPeriodYear>::iterator year_period_itr;
        for (year_period_itr = cfg->YearPeriod.begin(); year_period_itr != cfg->YearPeriod.end(); ++year_period_itr)
        {
            int dStart = year_period_itr->second.pye_start_day;
            int dEnd = year_period_itr->second.pye_end_day;

            int mStart = year_period_itr->second.pye_start_month;
            int mEnd = year_period_itr->second.pye_end_month;

            int start = (mStart * 100) + dStart;
            int end = (mEnd * 100) + dEnd;

            if (cdt >= start && cdt <= end) {
                isYearPeriodActive = true;
                break;
            }
        }
        if (!isYearPeriodActive)
        {
            LOG_DEBUG("Year period is not valid");
            return "PARKING NOT ALLOWED";
        }

        if(total_duration_min > maxMin)
        {
            total_duration_min = maxMin;
            break;
        }

        // If reached end of worktime go to next day
        if(inputDate.time() >= worktime_to)
        {
            int carry_over_status = 0;
            carry_over_status = cfg->PaymentOption.find(payment_option)->second.pop_carry_over;
            if (carry_over_status < 1) break;

            inputDate = inputDate.addDays(1);
            overtime = true;
            return GetDurationFromCost(cfg, payment_option, inputDate.toString(Qt::ISODate).toStdString().c_str(), money_left ,true, prepaid);
        }

        if(money_left > 1)
            inputDate = inputDate.addSecs(60);

        if(price_per_unit > 0) total_duration_min +=1;
        money_left -= price_per_unit;

        //qDebug() <<"Timestamp:" << inputDate << ", total duration min: " << total_duration_min << ", money left = " << money_left;
    }

    //    if ((total_duration_min < minMin) || (price / price_per_unit) < minMin)
    //    {
    //        LOG_DEBUG("Total duration is lower than min_min");
    //        inputDate.time() = worktime_from;
    //        total_duration_min = 0;
    //    }

    double ret_val = 0;
    // double calc_price = (int)total_duration_min - (int)price / price_per_unit;

    //if (calc_price > 0 && total_duration_min > 0)
    //{
    //    inputDate = inputDate.addSecs(-(int)ceil(calc_price) * 60);
    //}

    if(price >= min_price && total_duration_min >= minMin)
        qDebug() << "GetDurationFromCost(): Valid until: " << inputDate.toString(Qt::ISODate);
    else
    {
        qDebug() << "Parking not allowed";
        total_duration_min = 0;
    }

    ret_val = total_duration_min;
    if(ret_val < 0) ret_val = 0;
    qDebug() << "Duration: " << ret_val;
    if (ret_val <= 0) return "PARKING NOT ALLOWED";

    total_duration_min = 0;
    return inputDate.toString(Qt::ISODate).toStdString();
}

///////////////////////////////////////

/// <inheritdoc/>
///

uint32_t Calculator::GetCostFromDuration(Configuration *cfg,
                                         QDateTime const &start,
                                         quint64 timeStepInMinutes) const {
    // for instance, a tariff as used in Schoenau, Koenigssee: only steps, no
    // special days, nonstop.
    if (cfg->YearPeriod.size() == 0
     && cfg->SpecialDays.size() == 0
     && cfg->SpecialDaysWorktime.size() == 0) {
        QDateTime const end = start.addSecs(timeStepInMinutes*60);
        return GetCostFromDuration(cfg, start, end);
    }
    return 0;
}

uint32_t Calculator::GetCostFromDuration(Configuration * cfg,
                                         QDateTime const &start,
                                         QDateTime const &end) const {
    if (cfg->YearPeriod.size() == 0
     && cfg->SpecialDays.size() == 0
     && cfg->SpecialDaysWorktime.size() == 0) {
        int const timeStepInMinutes = start.secsTo(end) / 60;
        return GetPriceForTimeStep(cfg, timeStepInMinutes);
    }
    return 0;
}




///////////////////////////////////////

/// <inheritdoc/>
double Calculator::GetCostFromDuration(Configuration* cfg,
                                       uint8_t payment_option,
                                       const QDateTime start_datetime,
                                       QDateTime &end_datetime,
                                       int durationMinutes,
                                       bool nextDay,
                                       bool prepaid)
{
    if (cfg->YearPeriod.size() == 0
        && cfg->SpecialDays.size() == 0
        && cfg->SpecialDaysWorktime.size() == 0)
    {
        end_datetime = start_datetime.addSecs(durationMinutes*60);
        return GetCostFromDuration(cfg, start_datetime, end_datetime);
    }

    //Get min and max time defined in JSON
    static int const minMin = std::max((int)cfg->PaymentOption.find(payment_option)->second.pop_min_time, 0);
    static int const maxMin = std::max((int)cfg->PaymentOption.find(payment_option)->second.pop_max_time, 0);

    static const bool checkMinMaxMinutes = [](int minMin, int maxMin){ return (minMin < maxMin) ? true : false; }(minMin, maxMin);

    if (!checkMinMaxMinutes) {
        qCritical() << QString("ERROR: CONDITION minMin < maxMin (%1 < %2) IS NOT VALID").arg(minMin).arg(maxMin);
        return 0.0;
    }

    // Get input date
    QDateTime inputDate = start_datetime;

    // Get day of week
    int const weekdayId = inputDate.date().dayOfWeek();

    // weekdayId = Utilities::ZellersAlgorithm(inputDate.date().day(),inputDate.date().month(),inputDate.date().year());

    // Check overtime
    if (!overtime) {
        if (durationMinutes > maxMin) {
            qWarning() << QString("Total duration >= max_min (%1 >= %2)").arg(durationMinutes).arg(maxMin);
            return maxMin;
        }

        if (durationMinutes < minMin) {
            qWarning() << QString("Total duration <= minMin (%1 <= %2)").arg(durationMinutes).arg(minMin);
            return 0.0f;
        }
    }

    double day_price = 0.0;
    int current_special_day_id = -1;
    double price_per_unit = 0.0f;

    int const timeRanges = std::max((int)cfg->WeekDaysWorktime.count(weekdayId), 1);
    QScopedArrayPointer<TariffTimeRange> worktime(new TariffTimeRange[timeRanges]);
    int index = 0;

    if(Utilities::CheckSpecialDay(cfg,
                                  inputDate.toString(Qt::ISODate).toStdString().c_str(),
                                  &current_special_day_id,
                                  &day_price)) {
        // Set special day price
        price_per_unit = Utilities::CalculatePricePerUnit(day_price);
        worktime[index].setTimeRange(QTime::fromString(cfg->SpecialDaysWorktime.find(current_special_day_id)->second.pedwt_time_from.c_str()),
                                     QTime::fromString(cfg->SpecialDaysWorktime.find(current_special_day_id)->second.pedwt_time_to.c_str()));
    } else {
        // Set new price for the normal day

        int pop_id = cfg->PaymentOption.find(payment_option)->second.pop_id;
        day_price = cfg->PaymentRate.find(pop_id)->second.pra_price;

        int durationId = cfg->PaymentRate.find(pop_id)->second.pra_payment_unit_id;
        double durationUnit = cfg->Duration.find(durationId)->second.pun_duration;
        price_per_unit = Utilities::CalculatePricePerUnit(day_price,durationUnit);

        // If no working day found, skip it (recursively call method again)
        if (cfg->WeekDaysWorktime.count(weekdayId) <= 0) {
            // When no workday found, go to next available day
            qDebug() << "No workday found, trying to find next available day";
            inputDate = inputDate.addDays(1);
            return floor(GetCostFromDuration(cfg, payment_option, inputDate, end_datetime, durationMinutes, true, prepaid));
        }

        for (auto[itr, rangeEnd] = cfg->WeekDaysWorktime.equal_range(weekdayId); itr != rangeEnd; ++itr) {
            qCritical() << itr->first << itr->second.pwd_time_from.c_str() << itr->second.pwd_time_to.c_str();
            worktime[index].setTimeRange(QTime::fromString(itr->second.pwd_time_from.c_str()),
                                         QTime::fromString(itr->second.pwd_time_to.c_str()));
            index += 1;
        }
    }

    if (price_per_unit < 0) price_per_unit = 1.0f;
    qDebug() << "Calculated price per minute=" << price_per_unit;

    double costFromDuration = 0.0;
    for (int w = 0; w < index; ++w) {
        QTime worktime_from = worktime[w].getTimeFrom();
        QTime worktime_to = worktime[w].getTimeUntil();

        if (price_per_unit == 0) {
            inputDate = inputDate.addDays(1);
            inputDate.setTime(worktime_from);
            double const partialCost = GetCostFromDuration(cfg, payment_option, inputDate, end_datetime, durationMinutes, true, prepaid);
            if (partialCost <= __DBL_MIN__) {
                return 0.0;
            }
            costFromDuration += partialCost;
            continue;
        }

        // If overtime flag is set
        if (overtime || nextDay) {
            inputDate.setTime(worktime_from);
            overtime = false;
        }

        // Check prepaid
        if (!prepaid) {
            if ((inputDate.time() < worktime_from) || (inputDate.time() > worktime_to)) {
                qDebug() << "[STOP] * Ticket is not valid * ";
                return 0.0f;
            }
        } else {
            qDebug() << "* PREPAID MODE ACTIVE *";
            if (inputDate.time() < worktime_from) {
                inputDate.setTime(worktime_from);
            } else if(inputDate.time() > worktime_to) {
                qDebug() << " *** PREPAID *** Current time is past the time range end, searching for next available day";
                inputDate = inputDate.addDays(1);
                double const partialCost = GetCostFromDuration(cfg, payment_option, inputDate, end_datetime, durationMinutes, true, prepaid);
                if (partialCost < __DBL_MIN__) {
                    return 0.0;
                }
                costFromDuration += partialCost;
                continue;
            }
        }

        while(durationMinutes > 0) {
            // Check for active year period
            if (std::none_of(cfg->YearPeriod.begin(),
                             cfg->YearPeriod.end(),
                    [&inputDate](std::pair<int, ATBPeriodYear> const &year) {
                        QDate const input(2004, // 2004 is a leap year
                                          inputDate.date().month(),
                                          inputDate.date().day());
                        QDate const s(2004, year.second.pye_start_day, year.second.pye_start_month);
                        QDate const e(2004, year.second.pye_end_day, year.second.pye_end_month);
                        return (input >= s && input <= e);
                    })) {
                qCritical() << "NO VALID YEAR PERIOD";
                return 0.0;
            }

            // Go to next day if minutes not spent
            if(inputDate.time() >= worktime_to) {
                // check for carry_over status
                if (cfg->PaymentOption.find(payment_option)->second.pop_carry_over < 1) {
                    break;
                }

                qDebug() << "Reached end of worktime, searching for the next working day";

                inputDate = inputDate.addDays(1);
                overtime = true;
                double const partialCost = GetCostFromDuration(cfg, payment_option, inputDate, end_datetime, durationMinutes, false, false);
                if (partialCost < __DBL_MIN__) {
                    return 0.0;
                }
                costFromDuration += partialCost;
                break; // stop while, and continue in outer loop
            } else {
                // Increment input date minutes for each monetary unit
                inputDate = inputDate.addSecs(60);
                durationMinutes -= 1;
                costFromDuration += price_per_unit;
            }
        }
    }

    qDebug() << "GetCostFromDuration(): Valid until:" << inputDate.toString(Qt::ISODate);

    end_datetime = inputDate;

    //double ret_val = total_cost;
    //total_cost = 0.0f;
    //return ceil(ret_val);

    // TODO: runden nur falls oberster stack-rahmen

    return ceil(costFromDuration);
}



QList<int> Calculator::GetTimeSteps(Configuration *cfg) const {
    QList<int> timeSteps;

    int const pop_id = cfg->getPaymentOptions().pop_id;

    for (auto[itr, rangeEnd] = cfg->PaymentRate.equal_range(pop_id); itr != rangeEnd; ++itr)
    {
        int const durationId = itr->second.pra_payment_unit_id;
        int const durationUnit = cfg->Duration.find(durationId)->second.pun_duration;
        timeSteps << durationUnit;
    }

    return timeSteps;
}

uint32_t Calculator::GetPriceForTimeStep(Configuration *cfg, int timeStep) const {

    int const pop_id = cfg->getPaymentOptions().pop_id;

    for (auto[itr, rangeEnd] = cfg->PaymentRate.equal_range(pop_id); itr != rangeEnd; ++itr)
    {
        int const payment_unit_id = itr->second.pra_payment_unit_id;
        int const pun_id = cfg->Duration.find(payment_unit_id)->second.pun_id;

        Q_ASSERT(pun_id == payment_unit_id);

        int const pun_duration = cfg->Duration.find(payment_unit_id)->second.pun_duration;
        if (timeStep == pun_duration) {
            return (uint32_t)(itr->second.pra_price);
        }
    }

    return 0;
}

uint32_t Calculator::GetDurationForPrice(Configuration *cfg, int price) const {
    int const pop_id = cfg->getPaymentOptions().pop_id;

    uint32_t duration = 0;

    for (auto[itr, rangeEnd] = cfg->PaymentRate.equal_range(pop_id); itr != rangeEnd; ++itr)
    {
        int const durationId = itr->second.pra_payment_unit_id;
        int const pra_price = itr->second.pra_price;

        uint32_t const durationUnit = cfg->Duration.find(durationId)->second.pun_duration;

        if (pra_price == price) {
            return durationUnit;
        }

        if (pra_price < price) {
            duration = durationUnit;
        }
    }

    return duration;
}