#include "calculate_price.h"
#include "configuration.h"
#include "calculator_functions.h"
#include "payment_option.h"

#include <QFile>
#include <QFileInfo>
#include <QDateTime>
#include <QDebug>

static Calculator calculator;

int CALCULATE_LIBRARY_API get_zone_nr() {
    QFile zone("/etc/zone_nr");
    if (zone.exists()) {
        QFileInfo finfo(zone);
        if (finfo.size() <= 4) { // decimal 000\n
            if (zone.open(QIODevice::ReadOnly | QIODevice::Text)) {

                QTextStream in(&zone);
                return in.readLine(100).toInt();

            }
        }
    }
    return -1;
}

bool CALCULATE_LIBRARY_API init_tariff(parking_tariff_t **tariff, char const *config_file) {
    *tariff = new Configuration();

    int const zone = get_zone_nr();

    // DEBUG
    qCritical() << "init_tariff:";
    qCritical() << "      ... zone = " << zone;

    if (zone <= 0) {
        return false;
    }

    QString confFile(config_file);
    if (!confFile.endsWith(QChar('/'))) {
        confFile += "/";
    }

    char buffer[32];
    memset(buffer, 0x00, sizeof(buffer));
    snprintf(buffer, sizeof(buffer)-1, "tariff%02d.json", zone);
    confFile += buffer;

    QFile fname(confFile);
    if (fname.exists()) {
        if (fname.open(QIODevice::ReadOnly | QIODevice::Text)) {
            QString json = fname.readAll();
            return (*tariff)->ParseJson(*tariff, json.toStdString().c_str());
        }
    }

    return false;
}

void CALCULATE_LIBRARY_API free_tariff(parking_tariff_t *tariff) {
    delete tariff;
}

bool CALCULATE_LIBRARY_API compute_price_for_parking_ticket(
                                      parking_tariff_t *tariff,
                                      time_t start_parking_time, // in minutes
                                      time_t end_parking_time,   // in minutes
                                      struct price_t *price) {
    int const duration = end_parking_time - start_parking_time;
    if (duration > 0) {
        QDate const d(1970, 1, 1);
        QTime const t(0, 0, 0);
        QDateTime start(d, t, Qt::UTC);
        start = start.toLocalTime().addSecs(start_parking_time * 60);
        if (start.isValid()) {
            QString cs = start.toString(Qt::ISODate);
            double cost = calculator.GetCostFromDuration(
                            tariff, PaymentOption::Option1,
                            cs.toLocal8Bit().constData(),
                            duration, false, true);
            price->units = cost;
            price->netto = cost;
            return true;
        }
    } else
    if (duration == 0) {
        memset(price, 0x00, sizeof(*price));
        return true;
    }
    qCritical() << "ERROR start_parking_time (" << start_parking_time << ") <"
                << "end_parking_time (" << end_parking_time << ")";
    return false;
}