#include "calculator_functions.h"
#include "payment_method.h"
#include "utilities.h"
#include "tariff_log.h"

#include <sstream>
#include <QDateTime>
#include <qdebug.h>

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

/// <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 current date time from input
	struct tm current_datetime = Utilities::DateTimeToStructTm(start_datetime);
	time_t current_datetime_t;

	// Get day of week
	DayOfWeek weekdayId = DayOfWeek::UndefinedDay;
	weekdayId = Utilities::GetDayOfWeek(&current_datetime);

	//std::stringstream ss;

	// ss << "*** Input date is: " << start_datetime << " [weekday id = " << weekdayId << "]" << endl;
	LOG_DEBUG("*** Input date is: ", start_datetime, " [weekday id = ", weekdayId, "]");

	double minMin = 0;
	minMin = cfg->PaymentOption.find(payment_option)->second.pop_min_time;
	if (minMin < 0) minMin = 0;

	double maxMin = 0;
	maxMin = cfg->PaymentOption.find(payment_option)->second.pop_max_time;
	if (maxMin <= 0) maxMin = 60;

	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";
	}

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

	double day_price = 0.0f;
	int current_special_day_id = -1;
	bool is_special_day = Utilities::CheckSpecialDay(cfg, start_datetime, &current_special_day_id, &day_price);
	LOG_DEBUG("Special day: ", is_special_day);

	double money_left = price;
	LOG_DEBUG("Total money:", money_left);

	double price_per_unit = 0.0f;

	string worktime_from = "";
	string worktime_to = "";

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

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

		if (found <= 0)
		{
			LOG_DEBUG("- No workday found, trying to find next available day");
			current_datetime_t = mktime(&current_datetime);
			current_datetime_t += 86400;
			current_datetime = *localtime(&current_datetime_t);

			char buffer_datetime[80];
			strftime(buffer_datetime, 80, "%Y-%m-%dT%H:%M:%S", &current_datetime);

			// Make new datetime string and call function again recursively
			start_datetime = buffer_datetime;
			return GetDurationFromCost(cfg, payment_option, start_datetime, price, true);
		}

		worktime_from = cfg->WeekDaysWorktime.find(weekdayId)->second.pwd_time_from;
		worktime_to = cfg->WeekDaysWorktime.find(weekdayId)->second.pwd_time_to;
	}

	if (price_per_unit < 0) price_per_unit = 1.0f;
	LOG_DEBUG("Calculated price per minute: ", price_per_unit);

	LOG_DEBUG("Worktime from: ", worktime_from);
	LOG_DEBUG("Worktime to: ", worktime_to);

	struct tm from_tm;
	struct tm to_tm;

	from_tm = Utilities::TimeToStructTm(worktime_from.c_str(), current_datetime.tm_year, current_datetime.tm_mon, current_datetime.tm_mday, current_datetime.tm_wday);
	from_tm.tm_year = current_datetime.tm_year;
	from_tm.tm_mon = current_datetime.tm_mon;
	from_tm.tm_wday = current_datetime.tm_wday;
	from_tm.tm_mday = current_datetime.tm_mday;

	to_tm = Utilities::TimeToStructTm(worktime_to.c_str(), current_datetime.tm_year, current_datetime.tm_mon, current_datetime.tm_mday, current_datetime.tm_wday);
	to_tm.tm_year = current_datetime.tm_year;
	to_tm.tm_mon = current_datetime.tm_mon;
	to_tm.tm_wday = current_datetime.tm_wday;
	to_tm.tm_mday = current_datetime.tm_mday;

	// Convert tm structures to time_t
	current_datetime_t = mktime(&current_datetime);
	time_t from_datetime_t = mktime(&from_tm);
	time_t to_datetime_t = mktime(&to_tm);

	/*Newly added */
	//current_datetime.tm_hour = from_tm.tm_hour;
	//current_datetime.tm_min = from_tm.tm_min;
	//current_datetime.tm_sec = from_tm.tm_sec;
	//current_datetime_t = mktime(&current_datetime);

	// If overtime flag is set
	if (overtime || nextDay)
	{
		current_datetime.tm_hour = from_tm.tm_hour;
		current_datetime.tm_min = from_tm.tm_min;
		current_datetime.tm_sec = from_tm.tm_sec;
		current_datetime_t = mktime(&current_datetime);
		LOG_DEBUG(" *** New input date set according to worktime: ", asctime(&current_datetime));
		overtime = false;
	}

	// Validate ticket
	if (!prepaid)
	{
		if ((current_datetime_t < from_datetime_t) || (current_datetime_t > to_datetime_t))
		{
			LOG_DEBUG("[STOP] * Ticket is not valid * ");
			return "PARKING NOT ALLOWED";
		}
	}
	else
	{
		LOG_DEBUG("* PREPAID MODE ACTIVE *");

		if (current_datetime_t < from_datetime_t)
		{
			current_datetime.tm_hour = from_tm.tm_hour;
			current_datetime.tm_min = from_tm.tm_min;
			current_datetime.tm_sec = from_tm.tm_sec;
			current_datetime_t = mktime(&current_datetime);
			LOG_DEBUG(" *** PREPAID *** Current time is before the time range start, adjusting time to: ", asctime(&current_datetime));
		}
		else if (current_datetime_t > to_datetime_t)
		{
			LOG_DEBUG(" *** PREPAID *** Current time is past the time range end, searching for next available day");
			current_datetime_t = mktime(&current_datetime);
			current_datetime_t += 86400;
			current_datetime = *localtime(&current_datetime_t);

			char buffer_datetime[80];
			strftime(buffer_datetime, 80, "%Y-%m-%dT%H:%M:%S", &current_datetime);

			//Make new datetime string and call function again recursively
			start_datetime = buffer_datetime;
			return GetDurationFromCost(cfg, payment_option, start_datetime, price, true, prepaid);
		}
	}

	while (true)
	{
		if (!Utilities::IsYearPeriodActive(cfg, &current_datetime))
		{
			LOG_DEBUG("Year period is not valid");
			return "PARKING NOT ALLOWED";
		}

		// Increment by 1 minute
		current_datetime_t = mktime(&current_datetime);
		current_datetime_t += 60;
		current_datetime = *localtime(&current_datetime_t);
		total_duration_min += 1.0f;
		money_left -= price_per_unit;


		// If no money left (e.g. spent all of the money before reaching end of worktime)
		if (money_left <= 0)
		{
			LOG_DEBUG("No money left ");
			break;
		}
		else
		{
			if (total_duration_min >= maxMin)
			{
				LOG_DEBUG("Total duration is greater or equal to max_min");

				current_datetime_t = mktime(&current_datetime);
				current_datetime_t -= 60;
				current_datetime = *localtime(&current_datetime_t);
				total_duration_min = maxMin;
				break;
			}

			// If money has left but the end of worktime has been reached (go to next day)
			if (current_datetime_t >= to_datetime_t)
			{
				total_duration_min -= 1.0f;

				int carry_over_status = 0;
				carry_over_status = cfg->PaymentOption.find(payment_option)->second.pop_carry_over;
				LOG_DEBUG("Carry over status: ", carry_over_status);
				if (carry_over_status < 1) break;

				LOG_DEBUG("Reached end of worktime");
				LOG_DEBUG("Trying to find next available day, money left = ", money_left);
				current_datetime_t = mktime(&current_datetime);
				current_datetime_t += 86400;
				current_datetime = *localtime(&current_datetime_t);

				char buffer_datetime[80];
				strftime(buffer_datetime, 80, "%Y-%m-%dT%H:%M:%S", &current_datetime);

				// Make new datetime string and call function again recursively
				start_datetime = buffer_datetime;
				overtime = true;
                return GetDurationFromCost(cfg, payment_option, start_datetime, price);
			}
		}
	}

	time_t valid_until_datetime_t = current_datetime_t;

	if ((total_duration_min < minMin) || (price / price_per_unit) < minMin)
	{
		LOG_DEBUG("Total duration is lower than min_min");
		//valid_until_datetime_t += (minMin - total_duration_min) * 60;
		//total_duration_min = minMin;
		//return "PARKING NOT ALLOWED";

		valid_until_datetime_t = from_datetime_t;
		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)
	{
		valid_until_datetime_t -= (int)ceil(calc_price) * 60;
		ret_val = total_duration_min - calc_price;
	}
	else ret_val = total_duration_min;

	cout << "Total minutes: " << (int)ret_val << endl;
    if (ret_val <= 0) return "PARKING NOT ALLOWED";

#ifdef __linux__
    #if !defined(_SVID_SOURCE) && !defined(_XOPEN_SOURCE)
        // needed for timezone-correction
        #error "!defined(_SVID_SOURCE) && !defined(_XOPEN_SOURCE)"
    #else
        // timezone correction: localtime() needs argument in UTC-timezone
        // The global variable 'timezone' is set by tzset(), see
        // https://linux.die.net/man/3/tzset, so I change of the timezone will
        // also change the value of the variable 'timezone'.
        valid_until_datetime_t += timezone;
    #endif
#else // windows, only for testing
    static const long timezone = -3600;
    valid_until_datetime_t += timezone;
#endif

    struct tm valid_until_datetime;
    memset(&valid_until_datetime, 0x00, sizeof(valid_until_datetime));

    if (!localtime_r(&valid_until_datetime_t, &valid_until_datetime)) {
        return "LOCALTIME_R() ERROR";
    }

    // return in ISO-format: "%Y-%m-%dT%H:%M:%S"
    char buf[128];
    memset(buf, 0x00, sizeof(buf));
    strftime(buf, sizeof(buf)-1, "%Y-%m-%dT%H:%M:%S", &valid_until_datetime);

    LOG_DEBUG("Ticket is valid until ", buf);

	total_duration_min = 0.0f;
    return std::string(buf);
}

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

/// <inheritdoc/>
double Calculator::GetCostFromDuration(Configuration* cfg, uint8_t payment_option, const char* start_datetime, double durationMin, bool nextDay, bool prepaid)
{
    // Get input date
    QDateTime inputDate = QDateTime::fromString(start_datetime,Qt::ISODate);

    // 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->PaymentOption.find(payment_option)->second.pop_min_time;

    double maxMin = 0;
    maxMin = cfg->PaymentOption.find(payment_option)->second.pop_max_time;

    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 0.0f;
    }
    if (maxMin <= minMin)
    {
        LOG_ERROR("Error: max_min cannot be lower or equal than min_min");
        return 0.0f;
    }

    // Check overtime
    if (!overtime)
    {
        if (durationMin > maxMin)
        {
            LOG_WARNING("Total duration is greater or equal to max_min");
            return maxMin;
        }

        if (durationMin < minMin)
        {
            LOG_WARNING("Total duration is lower or equal to min_min");
            return 0.0f;
        }
    }

    // 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);

    total_duration_min = durationMin;
    LOG_DEBUG("Total min:", total_duration_min);

    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
        day_price = cfg->PaymentRate.find(payment_option)->second.pra_price;
        price_per_unit = Utilities::CalculatePricePerUnit(day_price);

        // 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 floor(GetCostFromDuration(cfg, payment_option, inputDate.toString(Qt::ISODate).toStdString().c_str(), durationMin, 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;
    LOG_DEBUG("Calculated price per minute: ", price_per_unit);

    if (price_per_unit == 0)
    {
        inputDate = inputDate.addDays(1);
        inputDate.setTime(worktime_from);
        return GetCostFromDuration(cfg, payment_option, inputDate.toString(Qt::ISODate).toStdString().c_str(), durationMin, true, prepaid);
    }

    // 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 0.0f;
        }
    }
    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 GetCostFromDuration(cfg, payment_option, inputDate.toString(Qt::ISODate).toStdString().c_str(), durationMin, true, prepaid);
        }
    }

    while(true)
    {
        if(total_duration_min <= 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 0.0f;
        }

        // Go to next day if minutes not spent
        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;

            LOG_DEBUG("Reached end of worktime, searching for the next working day");
            inputDate = inputDate.addDays(1);
            overtime = true;
            return GetCostFromDuration(cfg, payment_option, inputDate.toString(Qt::ISODate).toStdString().c_str(), total_duration_min);
        }

        // Increment input date minutes for each monetary unit
        inputDate = inputDate.addSecs(60);
        total_duration_min -=1;
        total_cost += price_per_unit;

    }
    qDebug() << "Valid until:" << inputDate.toString(Qt::ISODate).toStdString().c_str();
    double ret_val = total_cost;
    total_cost = 0.0f;
    return ceil(ret_val);
}