// SPDX-License-Identifier: GPL-3.0-or-later

/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
*
* Copyright (C) 2013 - 2024, nymea GmbH
* Copyright (C) 2024 - 2025, chargebyte austria GmbH
*
* This file is part of nymea-energy-plugin-nymea.
*
* nymea-energy-plugin-nymea.s free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* nymea-energy-plugin-nymea.s distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with nymea-energy-plugin-nymea. If not, see <https://www.gnu.org/licenses/>.
*
* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */

#include "energyratioscalculator.h"

#include <algorithm>

void EnergyRatiosCalculator::reset()
{
    m_hasBaseline = false;
    m_baseProduction = 0.0;
    m_baseReturn = 0.0;
    m_baseConsumption = 0.0;
    m_baseAcquisition = 0.0;
    m_baseDay = 0;
}

EnergyRatiosCalculator::Ratios EnergyRatiosCalculator::compute(double totalProduction,
                                                               double totalReturn,
                                                               double totalConsumption,
                                                               double totalAcquisition,
                                                               const QDateTime &now)
{
    const qint64 day = localDay(now);

    // Reseed si : 1er appel, nouveau jour local, OU compteur non monotone
    // (Δ<0 → restart nymead / re-add thing / rollover). Jamais de ratio négatif.
    const bool nonMonotone = m_hasBaseline &&
        (totalProduction < m_baseProduction ||
         totalReturn < m_baseReturn ||
         totalConsumption < m_baseConsumption ||
         totalAcquisition < m_baseAcquisition);

    if (!m_hasBaseline || m_baseDay != day || nonMonotone) {
        m_hasBaseline = true;
        m_baseDay = day;
        m_baseProduction = totalProduction;
        m_baseReturn = totalReturn;
        m_baseConsumption = totalConsumption;
        m_baseAcquisition = totalAcquisition;
    }

    const double dProduction = totalProduction - m_baseProduction;
    const double dReturn = totalReturn - m_baseReturn;
    const double dConsumption = totalConsumption - m_baseConsumption;
    const double dAcquisition = totalAcquisition - m_baseAcquisition;

    Ratios result;
    result.autoconsommationValid = ratio(dProduction - dReturn, dProduction, &result.autoconsommation);
    result.autonomieValid = ratio(dConsumption - dAcquisition, dConsumption, &result.autonomie);
    return result;
}

// Ratio en % borné [0, 100]. Dénominateur ≤ 0 (nuit sans prod, etc.) → n/a
// (retourne false) — jamais de NaN.
bool EnergyRatiosCalculator::ratio(double numerator, double denominator, double *outPercent)
{
    if (denominator <= 0)
        return false;
    *outPercent = std::clamp(numerator / denominator * 100.0, 0.0, 100.0);
    return true;
}

qint64 EnergyRatiosCalculator::localDay(const QDateTime &now)
{
    // Index de jour local stable (minuit local) — équivalent au _localDay interim.
    return now.date().toJulianDay();
}