<?php
declare(strict_types=1);

include_once __DIR__ . '/libs/vendor/autoload.php'; // TCPDF via Composer

class Abrechnung extends IPSModule
{
    public function Create()
    {
        parent::Create();

        // Eigenschaften
        $this->RegisterPropertyString('Users', '[]');
        $this->RegisterPropertyString('PowerMeters', '[]');
        $this->RegisterPropertyString('WaterMeters', '[]');
        $this->RegisterPropertyString('Tariffs', '[]');

        // Variablen
        $this->RegisterVariableInteger('FromDate', 'Startdatum', '~UnixTimestamp', 1);
        $this->RegisterVariableInteger('ToDate', 'Enddatum', '~UnixTimestamp', 2);
        $this->RegisterVariableString('LastResult', 'Letzte Abrechnung', '', 3);
        $this->EnableAction('FromDate');
        $this->EnableAction('ToDate');

        // Abrechnungs-Button
        $this->RegisterScript('StartBilling', 'Abrechnung starten', "<?php IPS_RequestAction(" . $this->InstanceID . ", 'StartBilling', ''); ?>");

        // PDF-Media-Objekt
        $this->RegisterMediaDocument('InvoicePDF', 'Letzte Rechnung', 'pdf');
    }

    public function ApplyChanges()
    {
        parent::ApplyChanges();
        IPS_LogMessage('Abrechnung', '✅ Modul geladen');
    }

    private function RegisterMediaDocument($Ident, $Name, $Extension, $Position = 0)
    {
        $mid = @IPS_GetObjectIDByIdent($Ident, $this->InstanceID);
        if ($mid === false) {
            $mid = IPS_CreateMedia(5); // 5 = Document
            IPS_SetParent($mid, $this->InstanceID);
            IPS_SetIdent($mid, $Ident);
            IPS_SetName($mid, $Name);
            IPS_SetPosition($mid, $Position);
            IPS_SetMediaFile($mid, 'media/' . $mid . '.' . $Extension, false);
        }
    }

    public function RequestAction($Ident, $Value)
    {
        switch ($Ident) {
            case 'FromDate':
            case 'ToDate':
                SetValue($this->GetIDForIdent($Ident), $Value);
                break;

            case 'StartBilling':
                try {
                    $pdfContent = $this->GenerateInvoices();
                    if ($pdfContent && strlen($pdfContent) > 100) {
                        $mediaID = $this->GetIDForIdent('InvoicePDF');
                        IPS_SetMediaContent($mediaID, base64_encode($pdfContent));
                        SetValue($this->GetIDForIdent('LastResult'), 'Abrechnung vom ' . date('d.m.Y H:i'));
                        echo "✅ PDF erfolgreich erstellt.";
                    } else {
                        echo "❌ Fehler bei der PDF-Erstellung.";
                    }
                } catch (Throwable $e) {
                    echo "❌ Ausnahmefehler: " . $e->getMessage();
                }
                break;
        }
    }

    // ===========================================================
    // 🧾 Hauptlogik: Rechnungserstellung für alle Benutzer
    // ===========================================================
    public function GenerateInvoices()
    {
        $from = GetValue($this->GetIDForIdent('FromDate'));
        $to   = GetValue($this->GetIDForIdent('ToDate'));

        $users   = json_decode($this->ReadPropertyString('Users'), true);
        $power   = json_decode($this->ReadPropertyString('PowerMeters'), true);
        $water   = json_decode($this->ReadPropertyString('WaterMeters'), true);
        $tariffs = json_decode($this->ReadPropertyString('Tariffs'), true);

        if (!class_exists('TCPDF')) return false;

        $pdf = new TCPDF('P', 'mm', 'A4', true, 'UTF-8', false);
        $pdf->SetCreator('IPSymcon Abrechnung');
        $pdf->SetMargins(15, 15, 15);
        $pdf->SetAutoPageBreak(true, 20);
        $pdf->SetFont('dejavusans', '', 9);

    foreach ($users as $user) {
        IPS_LogMessage('Abrechnung', '→ Erstelle Seite für Benutzer: ' . $user['name']);
        $this->BuildUserInvoice($pdf, $user, $power, $water, $tariffs, $from, $to);
    }

        return $pdf->Output('Abrechnung.pdf', 'S');
    }

    // ===========================================================
    // 🧱 Layout / PDF-Aufbau pro Benutzerseite
    // ===========================================================
  private function CalculatePowerCosts(array $powerMeters, array $tariffs, int $userId, int $from, int $to): array
{
    $html = "<table border='1' cellspacing='0' cellpadding='3' width='100%' style='font-size:8px;'>
        <tr style='background-color:#f0f0f0;'>
            <th>Zähler</th>
            <th>Typ</th>
            <th>Start</th>
            <th>Ende</th>
            <th>Zählerstand Start</th>
            <th>Zählerstand Ende</th>
            <th>Verbrauch</th>
            <th>Tarif (Rp)</th>
            <th>Kosten (CHF)</th>
        </tr>";
    $total = 0.0;

    foreach ($powerMeters as $m) {
        if ($m['user_id'] != $userId) continue;
        $cost = $this->AddMeterToPDFRow($m, $tariffs, $from, $to, 'Strombezug');
        $html .= $cost['row'];
        $total += $cost['value'];
    }

    $html .= "
        <tr style='background-color:#f9f9f9; font-weight:bold;'>
            <td colspan='8' align='right'>Total Stromkosten:</td>
            <td align='right'>" . number_format($total, 2) . "</td>
        </tr>
    </table><br>";

    return ['html' => $html, 'sum' => $total];
}

private function CalculatePowerCosts(array $powerMeters, array $tariffs, int $userId, int $from, int $to): array
{
    $html = "<table border='1' cellspacing='0' cellpadding='3' width='100%' style='font-size:8px;'>
        <tr style='background-color:#f0f0f0;'>
            <th>Zähler</th>
            <th>Typ</th>
            <th>Start</th>
            <th>Ende</th>
            <th>Zählerstand Start</th>
            <th>Zählerstand Ende</th>
            <th>Verbrauch</th>
            <th>Tarif (Rp)</th>
            <th>Kosten (CHF)</th>
        </tr>";
    $total = 0.0;

    foreach ($powerMeters as $m) {
        if ($m['user_id'] != $userId) continue;
        $cost = $this->AddMeterToPDFRow($m, $tariffs, $from, $to, 'Strombezug');
        $html .= $cost['row'];
        $total += $cost['value'];
    }

    $html .= "
        <tr style='background-color:#f9f9f9; font-weight:bold;'>
            <td colspan='8' align='right'>Total Stromkosten:</td>
            <td align='right'>" . number_format($total, 2) . "</td>
        </tr>
    </table><br>";

    return ['html' => $html, 'sum' => $total];
}

private function CalculateAdditionalCosts(array $waterMeters, array $tariffs, int $userId, int $from, int $to): array
{
    $html = "<table border='1' cellspacing='0' cellpadding='3' width='100%' style='font-size:8px;'>
        <tr style='background-color:#f0f0f0;'>
            <th>Zähler</th>
            <th>Typ</th>
            <th>Start</th>
            <th>Ende</th>
            <th>Zählerstand Start</th>
            <th>Zählerstand Ende</th>
            <th>Verbrauch</th>
            <th>Tarif (Rp)</th>
            <th>Kosten (CHF)</th>
        </tr>";
    $total = 0.0;

    foreach ($waterMeters as $m) {
        if ($m['user_id'] != $userId) continue;
        $type = $m['meter_type'] ?? 'Warmwasser';
        $cost = $this->AddMeterToPDFRow($m, $tariffs, $from, $to, $type);
        $html .= $cost['row'];
        $total += $cost['value'];
    }

    $html .= "
        <tr style='background-color:#f9f9f9; font-weight:bold;'>
            <td colspan='8' align='right'>Total Nebenkosten:</td>
            <td align='right'>" . number_format($total, 2) . "</td>
        </tr>
    </table><br>";

    return ['html' => $html, 'sum' => $total];
}


    // ===========================================================
    // 🧮 Datumskonvertierung – robust für JSON, String, Timestamp
    // ===========================================================
    private function toUnixTs($val, bool $endOfDay = false): ?int
    {
        if (is_int($val)) return $val;
        if (is_numeric($val)) return intval($val);

        if (is_string($val)) {
            $s = trim($val);
            if ($s !== '' && $s[0] === '{') {
                $obj = json_decode($s, true);
                if (is_array($obj) && isset($obj['year'], $obj['month'], $obj['day'])) {
                    $time = $endOfDay ? '23:59:59' : '00:00:00';
                    return strtotime(sprintf('%04d-%02d-%02d %s', $obj['year'], $obj['month'], $obj['day'], $time));
                }
            }
            $ts = strtotime($s);
            return $ts === false ? null : $ts;
        }
        return null;
    }

    // ===========================================================
    // 🔍 Archivwertsuche (deine getestete Version)
    // ===========================================================
    private function GetValueAt(int $varId, int $timestamp, bool $nearestAfter = true)
    {
        $archiveID = @IPS_GetInstanceListByModuleID('{43192F0B-135B-4CE7-A0A7-1475603F3060}')[0];
        if (!$archiveID || !IPS_VariableExists($varId)) return null;

        $maxDays = 365;
        $stepDays = 30;
        $valueFound = null;

        if ($nearestAfter) {
            for ($offset = 0; $offset < $maxDays; $offset += $stepDays) {
                $from = $timestamp + $offset * 86400;
                $to   = $from + $stepDays * 86400;
                $values = @AC_GetLoggedValues($archiveID, $varId, $from, $to, 0);
                if (!empty($values)) {
                    foreach ($values as $v) {
                        if ($v['TimeStamp'] >= $timestamp) {
                            return floatval($v['Value']);
                        }
                    }
                }
            }
        } else {
            for ($offset = 0; $offset < $maxDays; $offset += $stepDays) {
                $from = $timestamp - ($offset + $stepDays) * 86400;
                $to   = $timestamp - $offset * 86400;
                $values = @AC_GetLoggedValues($archiveID, $varId, $from, $to, 0);
                if (!empty($values)) {
                    $last = end($values);
                    return floatval($last['Value']);
                }
            }
        }

        return floatval(GetValue($varId));
    }

private function AddMeterToPDFRow($meter, $tariffs, $from, $to, $type)
{
    $rows = '';
    $totalCost = 0.0;
    $varId = $meter['var_consumption'];

    if (!IPS_VariableExists($varId)) {
        IPS_LogMessage('Abrechnung', "❌ Variable {$varId} für {$meter['name']} nicht gefunden");
        return ['row' => '', 'value' => 0];
    }

    date_default_timezone_set('Europe/Zurich');

    // 🔹 Filtere relevante Tarife nach Typ
    $filteredTariffs = array_filter($tariffs, function ($t) use ($type) {
        return strtolower(trim($t['unit_type'] ?? '')) === strtolower(trim($type));
    });

    if (empty($filteredTariffs)) {
        IPS_LogMessage('Abrechnung', "⚠ Keine passenden Tarife für {$type} gefunden");
        return ['row' => '', 'value' => 0];
    }

    // 🔹 Normiere Zeiträume
    foreach ($filteredTariffs as &$t) {
        $t['start_ts'] = $this->toUnixTs($t['start'], false);
        $t['end_ts']   = $this->toUnixTs($t['end'], true);
    }
    unset($t);
    usort($filteredTariffs, fn($a, $b) => ($a['start_ts'] ?? 0) <=> ($b['start_ts'] ?? 0));

    $currentStart = $from;

    while ($currentStart < $to) {
        // 🔹 Aktiven Tarif suchen
        $activeTariff = null;
        foreach ($filteredTariffs as $t) {
            if (($t['start_ts'] ?? 0) <= $currentStart && $currentStart <= ($t['end_ts'] ?? 0)) {
                $activeTariff = $t;
                break;
            }
        }

        if (!$activeTariff) {
            $activeTariff = [
                'start_ts' => $currentStart,
                'end_ts'   => $to,
                'price'    => 0.0,
                'unit_type'=> $type
            ];
        }

        $tariffEnd   = intval($activeTariff['end_ts']);
        $tariffPrice = floatval($activeTariff['price']);
        $tariffLabel = number_format($tariffPrice, 2, ',', '');

        // 🔹 Werte aus Archiv lesen
        $startValue = $this->GetValueAt($varId, $currentStart, true);
        $segmentEnd = ($tariffEnd < $to) ? $tariffEnd : $to;
        $endValue   = $this->GetValueAt($varId, $segmentEnd, true);

        if ($startValue === null || $endValue === null) break;

        $verbrauch = max(0, $endValue - $startValue);
        $kosten = round(($tariffPrice / 100) * $verbrauch, 2);
        $totalCost += $kosten;

        // 🔹 Kurze Datumsangaben
        $startDate = date('d.m.Y', $currentStart);
        $endDate   = date('d.m.Y', $segmentEnd);

        // 🔹 Tabellenzeile mit sichtbaren Linien
        $rows .= "
        <tr>
            <td border='1' align='left'  style='padding:2px;'>{$meter['name']}</td>
            <td border='1' align='left'  style='padding:2px;'>{$type}</td>
            <td border='1' align='center' style='padding:2px;'>{$startDate}</td>
            <td border='1' align='center' style='padding:2px;'>{$endDate}</td>
            <td border='1' align='right' style='padding:2px;'>" . number_format($startValue, 2) . "</td>
            <td border='1' align='right' style='padding:2px;'>" . number_format($endValue, 2) . "</td>
            <td border='1' align='right' style='padding:2px;'>" . number_format($verbrauch, 2) . "</td>
            <td border='1' align='right' style='padding:2px;'>" . $tariffLabel . "</td>
            <td border='1' align='right' style='padding:2px;'>" . number_format($kosten, 2) . "</td>
        </tr>";

        if ($tariffEnd < $to) {
            $currentStart = $tariffEnd + 1;
        } else {
            break;
        }
    }

    // 🔹 Fallback – kein Segment gefunden
    if ($rows === '') {
        $startVal = $this->GetValueAt($varId, $from, false);
        $endVal   = $this->GetValueAt($varId, $to, true);
        $verbrauch = max(0, $endVal - $startVal);
        $rows = "
        <tr>
            <td border='1' align='left'>{$meter['name']}</td>
            <td border='1' align='left'>{$type}</td>
            <td border='1' align='center'>" . date('d.m.Y', $from) . "</td>
            <td border='1' align='center'>" . date('d.m.Y', $to) . "</td>
            <td border='1' align='right'>" . number_format($startVal, 2) . "</td>
            <td border='1' align='right'>" . number_format($endVal, 2) . "</td>
            <td border='1' align='right'>" . number_format($verbrauch, 2) . "</td>
            <td border='1' align='right'>0.00</td>
            <td border='1' align='right'>0.00</td>
        </tr>";
    }

    return ['row' => $rows, 'value' => $totalCost];
}


}