Fix: do not divide by durationUnit when calling recursively GetCostFromDuration()

but set price_per_unit to day_price, and divide end result by durationUnit to
work around the rounding problem (for e.g. a full hour price).

library/include/mobilisis/calculate_price.h

@@ -109,6 +109,8 @@ CalcState CALCULATE_LIBRARY_API init_tariff(parking_tariff_t **tariff,
 void CALCULATE_LIBRARY_API free_tariff(parking_tariff_t *tariff);
 int CALCULATE_LIBRARY_API get_zone_nr(int zone = -1);
 
+int CALCULATE_LIBRARY_API compute_next_timestep(parking_tariff_t *tariff, int currentTimeMinutes, int UpDown);
+
 CalcState CALCULATE_LIBRARY_API compute_price_for_parking_ticket(       // deprecated
                                             parking_tariff_t *tariff,
                                             time_t start_parking_time,

library/include/mobilisis/calculator_functions.h

@@ -43,9 +43,6 @@ private:
     // For tariff of following structure: only steps, no special days, nonstop.
     uint32_t GetCostFromDuration(Configuration *cfg, QDateTime const &start, quint64 durationMinutes) const;
     uint32_t GetCostFromDuration(Configuration *cfg, QDateTime const &start, QDateTime const &end) const;
-
-
-    //
     uint32_t GetPriceForTimeStep(Configuration *cfg, int timeStep) const;
     uint32_t GetDurationForPrice(Configuration *cfg, int price) const;
 };

library/src/calculate_price.cpp

@@ -93,6 +93,44 @@ void CALCULATE_LIBRARY_API free_tariff(parking_tariff_t *tariff) {
 }
 
 
+//
+// UpDown 1 -> up; 0 -> down
+int CALCULATE_LIBRARY_API compute_next_timestep(parking_tariff_t *tariff, int currentTimeMinutes, int UpDown)
+{
+    static const QList<int> stepList = calculator.GetTimeSteps(tariff);
+
+    int currentStepIndex = stepList.indexOf(currentTimeMinutes);
+
+    if (currentStepIndex == -1) {
+        qCritical() << "compute_next_timestep() *NO STEP* for currentTimeMinutes (" << currentTimeMinutes << ")";
+        return  currentTimeMinutes;
+    }
+
+    if (UpDown == 1) { // UP
+        if (stepList[currentStepIndex] == stepList.last()) {
+            qCritical() << "compute_next_timestep() *NO NEXT STEP* for currentTimeMinutes (" << currentTimeMinutes << ")";
+            return  currentTimeMinutes;
+        }
+        else {
+            return stepList[currentStepIndex + 1];
+        }
+    }
+    if (UpDown == 0) { // DOWN
+        if (stepList[currentStepIndex] == stepList.first()) {
+            qCritical() << "compute_next_timestep() *NO PREVIOUS STEP* for currentTimeMinutes (" << currentTimeMinutes << ")";
+            return  currentTimeMinutes;
+        }
+        else {
+            return stepList[currentStepIndex - 1];
+        }
+    }
+
+    qCritical() << "compute_next_timestep() *CAN NOT COMPUTE* for currentTimeMinutes (" << currentTimeMinutes << ")";
+    return  currentTimeMinutes;
+}
+
+
+
 // this is currently not used
 CalcState CALCULATE_LIBRARY_API compute_price_for_parking_ticket(
         parking_tariff_t *tariff,

library/src/calculator_functions.cpp

@@ -118,17 +118,21 @@ std::string Calculator::GetDurationFromCost(Configuration* cfg,
                                             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)
     {
-        return QString().setNum(GetDurationForPrice(cfg, price)).toStdString();
+        inputDate = inputDate.addSecs(GetDurationForPrice(cfg, price) * 60);
+
+        return inputDate.toString(Qt::ISODate).toStdString();
     }
 
-    // Get input date
-    QDateTime inputDate = QDateTime::fromString(start_datetime,Qt::ISODate);
 
     // Get day of week
     int weekdayId = 0;
@@ -136,13 +140,13 @@ std::string Calculator::GetDurationFromCost(Configuration* cfg,
 
     //Get min and max time defined in JSON
     double minMin = 0;
-    minMin = cfg->PaymentOption.find(payment_option)->second.pop_min_time;
+    minMin = cfg->getPaymentOptions().pop_min_time;
 
     double maxMin = 0;
-    maxMin = cfg->PaymentOption.find(payment_option)->second.pop_max_time;
+    maxMin = cfg->getPaymentOptions().pop_max_time;
 
     double min_price = 0;
-    min_price = cfg->PaymentOption.find(payment_option)->second.pop_min_price;
+    min_price = cfg->getPaymentOptions().pop_min_price;
 
     if(price < min_price)
     {
@@ -452,11 +456,13 @@ double Calculator::GetCostFromDuration(Configuration* cfg, uint8_t payment_optio
     double price_per_unit = 0.0f;
     QTime worktime_from;
     QTime worktime_to;
+    double durationUnit = 60.0;
 
     if(is_special_day)
     {
-        // Set special day price
-        price_per_unit = Utilities::CalculatePricePerUnit(day_price);
+        // Set price_per_unit to special day price: at the end of the calculation
+        // divide by durationUnit to get correct price.
+        price_per_unit = 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());
     }
@@ -468,8 +474,13 @@ double Calculator::GetCostFromDuration(Configuration* cfg, uint8_t payment_optio
         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);
+        durationUnit = cfg->Duration.find(durationId)->second.pun_duration;
+        if (durationUnit == 0) {
+            durationUnit = 60.0;
+        }
+        // Set price_per_unit to day price: at the end of the calculation
+        // divide by durationUnit to get correct price.
+        price_per_unit = day_price;
 
         // If no working day found, skip it (recursively call method again)
         size_t found = 0;
@@ -480,7 +491,7 @@ double Calculator::GetCostFromDuration(Configuration* cfg, uint8_t payment_optio
         {
             LOG_DEBUG("- No workday found, trying to find next available day");
             inputDate = inputDate.addDays(1);
-            return floor(GetCostFromDuration(cfg, payment_option, inputDate, end_datetime, durationMin, true, prepaid));
+            return GetCostFromDuration(cfg, payment_option, inputDate, end_datetime, 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());
@@ -590,7 +601,7 @@ double Calculator::GetCostFromDuration(Configuration* cfg, uint8_t payment_optio
 
     double ret_val = total_cost;
     total_cost = 0.0f;
-    return ceil(ret_val);
+    return round(ret_val / durationUnit);
 }
 
 
@@ -630,20 +641,29 @@ uint32_t Calculator::GetPriceForTimeStep(Configuration *cfg, int timeStep) const
     return 0;
 }
 
+/**
+ * private: read price directly from config file (used with PaymentMethod::Steps)
+ *
+ * return duration in minutes for greatest pra_price < price
+ */
+
 uint32_t Calculator::GetDurationForPrice(Configuration *cfg, int price) const {
-    int const pop_id = cfg->getPaymentOptions().pop_id;
+    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 payment_unit_id = itr->second.pra_payment_unit_id;
-        int const pra_price = cfg->PaymentRate.find(payment_unit_id)->second.pra_price;
+        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 (price == pra_price) {
-            int const durationId = itr->second.pra_payment_unit_id;
-            int const durationUnit = cfg->Duration.find(durationId)->second.pun_duration;
             return durationUnit;
         }
+        if (pra_price < price) {
+            duration = durationUnit;
+        }
     }
 
-    return 0;
+    return duration;
 }