<?php
// ROI.php – Umsatz/Peak/Histogramm pro Artikel inkl. Bundleanteil
// liegt in /dist

require('../config.php');
require('../EpiApi.php');
require_once __DIR__ . '/../vendor/autoload.php';
date_default_timezone_set('Europe/Berlin');

use PhpOffice\PhpSpreadsheet\Spreadsheet;
use PhpOffice\PhpSpreadsheet\Writer\Xlsx;
use PhpOffice\PhpSpreadsheet\Style\Alignment;
use PhpOffice\PhpSpreadsheet\Cell\Coordinate;
use PhpOffice\PhpSpreadsheet\Cell\DataType;
use PhpOffice\PhpSpreadsheet\Style\Fill;

$Epi = new Epirent();

/* =========================
   Helpers
   ========================= */

function formatEuro(float $amount): string {
    $formatted = number_format(abs($amount), 2, ',', '.') . ' €';
    return $amount < 0 ? '-' . $formatted : $formatted;
}

function yearFromDate(?string $ymd): ?int {
    if (!$ymd || $ymd === '0000-00-00') return null;
    return (int)substr($ymd, 0, 4);
}

function safeYmd(?string $ymd): ?string {
    if (!$ymd || $ymd === '0000-00-00') return null;
    if (!preg_match('/^\d{4}-\d{2}-\d{2}$/', $ymd)) return null;
    return $ymd;
}

function ymdToTs(string $ymd): int {
    // midnight local
    return (new DateTime($ymd . ' 00:00:00'))->getTimestamp();
}

function tsToYmd(int $ts): string {
    return (new DateTime('@' . $ts))->setTimezone(new DateTimeZone('Europe/Berlin'))->format('Y-m-d');
}

function base64Json(array $data): string {
    return base64_encode(json_encode($data, JSON_UNESCAPED_UNICODE | JSON_UNESCAPED_SLASHES));
}

function apiJsonDecode($raw) {
    // requestEpiApi kann je nach Implementierung string ODER Stream liefern
    if (is_object($raw)) {
        // Guzzle Stream etc.
        if (method_exists($raw, 'getContents')) {
            $raw = $raw->getContents();
        } else {
            $raw = (string)$raw;
        }
    }
    if (!is_string($raw)) $raw = (string)$raw;
    $obj = json_decode($raw);
    return $obj;
}

/* =========================
   API Caches
   ========================= */

$productCache = [];       // [pk => productObj]
$bundleLeafCache = [];    // [bundlePk => [leafPk => amount]]
$rentPriceCache = [];     // [pk => float]

function getProduct(Epirent $Epi, int $productPk) {
    global $productCache;
    if ($productPk <= 0) return null;
    if (isset($productCache[$productPk])) return $productCache[$productPk];

    $res = apiJsonDecode($Epi->requestEpiApi('/v1/product/' . $productPk . '?cl=' . Epirent_Mandant));
    $prod = ($res && ($res->success ?? false) && !empty($res->payload[0])) ? $res->payload[0] : null;
    $productCache[$productPk] = $prod;
    return $prod;
}

function getRentPrice(Epirent $Epi, int $productPk): float {
    global $rentPriceCache;
    if (isset($rentPriceCache[$productPk])) return $rentPriceCache[$productPk];

    $p = getProduct($Epi, $productPk);
    $price = 0.0;
    if ($p && isset($p->pricing) && isset($p->pricing->price_rent)) {
        $price = (float)$p->pricing->price_rent;
    }
    $rentPriceCache[$productPk] = $price;
    return $price;
}

/**
 * Bundle-Komponenten rekursiv auflösen.
 * Ergebnis: [leafProductPk => amount]
 *
 * WICHTIG (Fix für "UJ90 hat (0)"):
 * - NUR virtuelle Produkte (is_virtual==true) werden expandiert.
 * - Nicht-virtuelle Produkte zählen IMMER als leaf – auch wenn sie materials haben (Zubehör/Case/etc.)
 *
 * - bevorzugt materials_ext.rent_fix (weil rent_fix sauberer ist)
 * - fallback materials
 * - Cycle-Guard über $stack
 */
function resolveBundleLeafMap(Epirent $Epi, int $productPk, array &$stack = []): array {
    global $bundleLeafCache;

    if ($productPk <= 0) return [];
    if (isset($bundleLeafCache[$productPk])) return $bundleLeafCache[$productPk];

    if (isset($stack[$productPk])) {
        // cycle detected
        return [];
    }
    $stack[$productPk] = true;

    $p = getProduct($Epi, $productPk);
    if (!$p) {
        unset($stack[$productPk]);
        return [];
    }

    // ✅ FIX: Nur virtuelle Produkte expandieren
    $isVirtual = (bool)($p->is_virtual ?? false);
    if (!$isVirtual) {
        unset($stack[$productPk]);
        $bundleLeafCache[$productPk] = [$productPk => 1.0];
        return $bundleLeafCache[$productPk];
    }

    // Komponentenliste auslesen (nur für virtuelle Produkte)
    $mats = [];

    // materials_ext.rent_fix bevorzugen
    if (!empty($p->materials_ext) && !empty($p->materials_ext->rent_fix) && is_array($p->materials_ext->rent_fix)) {
        $mats = $p->materials_ext->rent_fix;
    } elseif (!empty($p->materials) && is_array($p->materials)) {
        $mats = $p->materials;
    }

    // Wenn keine Komponenten => leaf
    if (empty($mats)) {
        unset($stack[$productPk]);
        $bundleLeafCache[$productPk] = [$productPk => 1.0];
        return $bundleLeafCache[$productPk];
    }

    $leaf = [];
    foreach ($mats as $m) {
        $childPk = (int)($m->mat_product_pk ?? 0);
        $amt = (float)($m->amount ?? 1);
        if ($childPk <= 0 || $amt <= 0) continue;

        // rekursiv
        $childLeaf = resolveBundleLeafMap($Epi, $childPk, $stack);
        foreach ($childLeaf as $leafPk => $leafAmt) {
            if (!isset($leaf[$leafPk])) $leaf[$leafPk] = 0.0;
            $leaf[$leafPk] += $amt * (float)$leafAmt;
        }
    }

    unset($stack[$productPk]);

    // falls aus irgendeinem Grund leer => als leaf behandeln
    if (empty($leaf)) $leaf = [$productPk => 1.0];

    $bundleLeafCache[$productPk] = $leaf;
    return $leaf;
}

/**
 * Bundle-Umsatz anteilig auf leaf-Produkte verteilen.
 * Gewichtung: rentPrice(leaf) * amount
 * Fallback: gleichverteilt nach amount
 */
function allocateBundleRevenue(Epirent $Epi, int $bundlePk, float $bundleRevenueNet): array {
    $leafMap = resolveBundleLeafMap($Epi, $bundlePk);
    if (empty($leafMap)) return [];

    $weights = [];
    $sumW = 0.0;

    foreach ($leafMap as $leafPk => $amt) {
        $rp = getRentPrice($Epi, (int)$leafPk);
        $w = $rp * (float)$amt;
        $weights[$leafPk] = $w;
        $sumW += $w;
    }

    // fallback: sumW=0 => gleich nach amount
    if ($sumW <= 0.0) {
        $sumAmt = array_sum($leafMap);
        if ($sumAmt <= 0.0) $sumAmt = (float)count($leafMap);
        $alloc = [];
        foreach ($leafMap as $leafPk => $amt) {
            $alloc[$leafPk] = $bundleRevenueNet * ((float)$amt / $sumAmt);
        }
        return $alloc;
    }

    $alloc = [];
    foreach ($weights as $leafPk => $w) {
        $alloc[$leafPk] = $bundleRevenueNet * ($w / $sumW);
    }
    return $alloc;
}

/* =========================
   Journal Cache
   ========================= */

$journalCache = [];
function getJournalByChapter(Epirent $Epi, int $chapterId): array {
    global $journalCache;

    if ($chapterId <= 0) return [];
    if (isset($journalCache[$chapterId])) return $journalCache[$chapterId];

    $url = '/v1/journal/filter?chid=' . $chapterId . '&cl=' . Epirent_Mandant;
    $res = apiJsonDecode($Epi->requestEpiApi($url));
    $payload = ($res && ($res->success ?? false) && isset($res->payload) && is_array($res->payload)) ? $res->payload : [];

    $journalCache[$chapterId] = $payload;
    return $payload;
}

/* =========================
   Interval aggregation (Peak/Histogram)
   ========================= */

// eventsDirect[productPk][ymd] += deltaQty
$eventsDirect = [];
$eventsIncl   = []; // direct + bundle

function addIntervalEvent(array &$events, int $productPk, string $startYmd, string $endYmd, float $qty): void {
    if ($productPk <= 0) return;
    $startYmd = safeYmd($startYmd);
    $endYmd = safeYmd($endYmd);
    if (!$startYmd || !$endYmd) return;
    if ($qty == 0.0) return;

    $startTs = ymdToTs($startYmd);
    $endTs   = ymdToTs($endYmd);
    if ($endTs < $startTs) return;

    // end+1 day
    $endPlusTs = $endTs + 86400;
    $endPlusYmd = tsToYmd($endPlusTs);

    if (!isset($events[$productPk])) $events[$productPk] = [];
    if (!isset($events[$productPk][$startYmd])) $events[$productPk][$startYmd] = 0.0;
    if (!isset($events[$productPk][$endPlusYmd])) $events[$productPk][$endPlusYmd] = 0.0;

    $events[$productPk][$startYmd] += $qty;
    $events[$productPk][$endPlusYmd] -= $qty;
}

/**
 * Aus Events Peak + Histogramm berechnen:
 * return ['peak'=>int, 'hist'=>[level=>days]]
 */
function computePeakAndHistogram(array $eventMap): array {
    if (empty($eventMap)) return ['peak' => 0, 'hist' => []];

    ksort($eventMap);
    $dates = array_keys($eventMap);

    $level = 0.0;
    $peak = 0.0;
    $hist = []; // [intLevel => floatDays]

    for ($i = 0; $i < count($dates); $i++) {
        $d = $dates[$i];
        $level += (float)$eventMap[$d];
        if ($level < 0) $level = 0;

        $intLevel = (int)round($level);
        if ($intLevel > $peak) $peak = $intLevel;

        // segment length until next date
        if ($i < count($dates) - 1) {
            $dTs = ymdToTs($d);
            $nTs = ymdToTs($dates[$i + 1]);
            $days = ($nTs - $dTs) / 86400.0;
            if ($days > 0 && $intLevel > 0) {
                if (!isset($hist[$intLevel])) $hist[$intLevel] = 0.0;
                $hist[$intLevel] += $days;
            }
        }
    }

    ksort($hist);
    // hist days runden
    foreach ($hist as $k => $v) $hist[$k] = (int)round($v);

    return ['peak' => (int)$peak, 'hist' => $hist];
}

/* =========================
   Data aggregation
   ========================= */

$rows = []; // Debug rows (HTML only, no excel)
$pivot = []; // direct revenue per year
$pivotB = []; // bundle revenue per year (alloc to leaf)
$meta = []; // product meta [pk=>['product_no'=>..,'title'=>..]]

$allYears = [];

function ensureMeta(Epirent $Epi, int $productPk, int $productNo, string $title): void {
    global $meta;
    if (!isset($meta[$productPk])) {
        $p = getProduct($Epi, $productPk);
        $meta[$productPk] = [
            'product_pk' => $productPk,
            'product_no' => $productNo ?: (int)($p->product_no ?? 0),
            'title'      => $title ?: (string)($p->name ?? ''),
        ];
    }
}

function addRevenue(array &$pivotRef, int $productPk, int $year, float $revenueNet): void {
    if ($productPk <= 0 || !$year) return;
    if (!isset($pivotRef[$productPk])) $pivotRef[$productPk] = [];
    if (!isset($pivotRef[$productPk][$year])) $pivotRef[$productPk][$year] = 0.0;
    $pivotRef[$productPk][$year] += $revenueNet;
}

/**
 * Eine Artikelzeile (aus Journal ODER direkt) verarbeiten
 */
function processLineItem(
    Epirent $Epi,
    array &$rows,
    int $invoicePk,
    string $invoiceDate,
    int $invoiceYear,
    ?int $chapterId,
    object $li,
    bool $isFromJournal
): void {
    global $pivot, $pivotB, $allYears, $eventsDirect, $eventsIncl;

    $type = (int)($li->type ?? -1);
    $productPk = (int)($li->product_pk ?? 0);
    if ($type !== 0 || $productPk <= 0) return; // nur echte Artikelpositionen

    $title = (string)($li->title ?? '');
    $productNo = (int)($li->product_no ?? 0);

    $qty = (float)($li->amount_total ?? 0);
    if ($qty <= 0) $qty = 0.0;

    // Zeitraum (für Peak/Histogramm)
    $dateStart = (string)($li->date_start ?? '');
    $dateEnd   = (string)($li->date_end ?? '');
    $dateStart = safeYmd($dateStart) ?: null;
    $dateEnd   = safeYmd($dateEnd) ?: null;

    // Umsatz netto (für Pivot)
    $revenueNet = (float)($li->sum_total_net ?? 0);

    ensureMeta($Epi, $productPk, $productNo, $title);

    // Jahr: AN RECHNUNGSDATUM gebunden (dein Wunsch)
    $year = $invoiceYear;
    if ($year) $allYears[$year] = true;

    // Direct Umsatz (auch wenn Zeitraum evtl. leer ist)
    if ($revenueNet != 0.0 && $year) {
        addRevenue($pivot, $productPk, $year, $revenueNet);
    }

    // Direct Auslastung (nur wenn Zeitraum da)
    if ($dateStart && $dateEnd && $qty > 0) {
        addIntervalEvent($eventsDirect, $productPk, $dateStart, $dateEnd, $qty);
        addIntervalEvent($eventsIncl,   $productPk, $dateStart, $dateEnd, $qty);
    }

    // Debug Row
    $rows[] = [
        'year'        => $year,
        'invoice_pk'  => $invoicePk,
        'invoice_date'=> $invoiceDate,
        'chapter_id'  => $chapterId ?? 0,
        'source'      => $isFromJournal ? 'journal' : 'direct',
        'product_pk'  => $productPk,
        'product_no'  => $productNo,
        'title'       => $title,
        'date_start'  => $dateStart ?? '',
        'date_end'    => $dateEnd ?? '',
        'qty'         => $qty,
        'revenue_net' => $revenueNet,
    ];

    /* ===== Bundle-Auflösung =====
       - Bundle-Erkennung NUR über is_virtual (Fix!)
       - Auslastung inkl Bundle: Komponenten bekommen qty*amount über Zeitraum
       - Umsatz inkl Bundle: Umsatz wird proportional auf Leaf-Produkte verteilt
    */
    $p = getProduct($Epi, $productPk);
    $isBundle = (bool)($p->is_virtual ?? false);  // ✅ FIX: nicht über materials ableiten

    if ($isBundle) {
        $leafMap = resolveBundleLeafMap($Epi, $productPk);

        // Umsatz allokieren
        if ($revenueNet != 0.0 && $year) {
            $alloc = allocateBundleRevenue($Epi, $productPk, $revenueNet);
            foreach ($alloc as $leafPk => $leafRevenue) {
                $leafPk = (int)$leafPk;
                ensureMeta($Epi, $leafPk, 0, '');
                addRevenue($pivotB, $leafPk, $year, (float)$leafRevenue);
            }
        }

        // Auslastung allokieren
        if ($dateStart && $dateEnd && $qty > 0) {
            foreach ($leafMap as $leafPk => $amt) {
                $leafPk = (int)$leafPk;
                $amt = (float)$amt;
                if ($leafPk <= 0 || $amt <= 0) continue;
                ensureMeta($Epi, $leafPk, 0, '');
                addIntervalEvent($eventsIncl, $leafPk, $dateStart, $dateEnd, $qty * $amt);
            }
        }
    }
}

/* =========================
   1) Invoices holen
   ========================= */

$invoiceAll = apiJsonDecode($Epi->requestEpiApi('/v1/invoice/all?ir=true&ib=true&cl=' . Epirent_Mandant));
$invoiceList = ($invoiceAll && ($invoiceAll->success ?? false) && is_array($invoiceAll->payload ?? null)) ? $invoiceAll->payload : [];

foreach ($invoiceList as $inv) {
    $invoicePk = (int)($inv->primary_key ?? 0);
    if ($invoicePk <= 0) continue;

    $invRes = apiJsonDecode($Epi->requestEpiApi('/v1/invoice/' . $invoicePk . '?cl=' . Epirent_Mandant));
    $invObj = ($invRes && ($invRes->success ?? false) && !empty($invRes->payload[0])) ? $invRes->payload[0] : null;
    if (!$invObj) continue;

    $invoiceDate = (string)($invObj->invoice_date ?? '');
    $invoiceYear = yearFromDate($invoiceDate) ?? 0;

    $orderItems = $invObj->order_items ?? [];
    if (!is_array($orderItems)) $orderItems = [];

    foreach ($orderItems as $oi) {
        $oiType = (int)($oi->type ?? -1);
        $oiPk   = (int)($oi->primary_key ?? 0);

        // 1) Kapitel-Zeile (type=5): chid ist primary_key der Kapitelzeile!
        if ($oiType === 5 && $oiPk > 0) {
            $chapterId = $oiPk;
            $journalItems = getJournalByChapter($Epi, $chapterId);

            foreach ($journalItems as $ji) {
                processLineItem($Epi, $rows, $invoicePk, $invoiceDate, $invoiceYear, $chapterId, $ji, true);
            }
            continue;
        }

        // 2) Direkte Artikel-Zeile ohne Kapitel (type=0)
        if ($oiType === 0 && (int)($oi->product_pk ?? 0) > 0) {
            processLineItem($Epi, $rows, $invoicePk, $invoiceDate, $invoiceYear, null, $oi, false);
            continue;
        }

        // Andere Typen ignorieren (Zwischensumme etc.)
    }
}

/* =========================
   2) Years + Pivot Rows bauen
   ========================= */

$years = array_keys($allYears);
sort($years);

// Pivot Rows: pro Produkt => revenueDirect / revenueIncl und PeakDirect / PeakIncl + Histogramme
$pivotRows = [];

foreach ($meta as $productPk => $m) {
    $productPk = (int)$productPk;

    // revenue direct/incl
    $sumDirect = 0.0;
    $sumIncl = 0.0;

    $row = [
        'product_pk' => $productPk,
        'product_no' => (int)($m['product_no'] ?? 0),
        'title'      => (string)($m['title'] ?? ''),
        'years'      => [],
        'total_direct'=> 0.0,
        'total_incl'  => 0.0,
        'peak_direct' => 0,
        'peak_incl'   => 0,
        'hist_direct' => [],
        'hist_incl'   => [],
    ];

    foreach ($years as $y) {
        $d = (float)($pivot[$productPk][$y]  ?? 0.0);
        $b = (float)($pivotB[$productPk][$y] ?? 0.0);
        $incl = $d + $b;

        $row['years'][$y] = ['direct'=>$d, 'incl'=>$incl];

        $sumDirect += $d;
        $sumIncl   += $incl;
    }

    $row['total_direct'] = $sumDirect;
    $row['total_incl']   = $sumIncl;

    // Peak + Histogram
    $pd = computePeakAndHistogram($GLOBALS['eventsDirect'][$productPk] ?? []);
    $pi = computePeakAndHistogram($GLOBALS['eventsIncl'][$productPk] ?? []);

    $row['peak_direct'] = (int)$pd['peak'];
    $row['peak_incl']   = (int)$pi['peak'];
    $row['hist_direct'] = $pd['hist'];
    $row['hist_incl']   = $pi['hist'];

    // Nur Produkte zeigen, die überhaupt irgendwo vorkommen (direct oder incl)
    if ($row['total_direct'] == 0.0 && $row['total_incl'] == 0.0 && $row['peak_direct'] == 0 && $row['peak_incl'] == 0) {
        continue;
    }

    $pivotRows[] = $row;
}

// Sort: nach Total_incl absteigend (inkl Bundle-Anteil ist meist interessanter)
usort($pivotRows, fn($a,$b) => ($b['total_incl'] <=> $a['total_incl']));

/* =========================
   3) Excel Export (nur Pivot)
   ========================= */

$exportDir = __DIR__ . '/exports';
if (!is_dir($exportDir)) {
    @mkdir($exportDir, 0775, true);
}
$timestamp = date('Ymd_His');
$excelFileName = "ROI_Artikel_Jahre_{$timestamp}.xlsx";
$excelFilePath = $exportDir . '/' . $excelFileName;
$excelDownloadUrl = 'exports/' . $excelFileName;

$spreadsheet = new Spreadsheet();
$sheet = $spreadsheet->getActiveSheet();
$sheet->setTitle('Pivot');

$cols = ['Produkt-PK','Artikel-Nr','Artikel','Peak','Peak (inkl. Bundle)','Summe','Summe (inkl. Bundle)'];
foreach ($years as $y) {
    $cols[] = (string)$y;
    $cols[] = (string)$y . ' (inkl. Bundle)';
}

$colCount = count($cols);
$lastColLetter = Coordinate::stringFromColumnIndex($colCount);

// Header
$sheet->setCellValue('A1', 'EpiWebview – ROI / Umsatz pro Artikel & Jahr');
$sheet->mergeCells('A1:' . $lastColLetter . '1');
$sheet->getStyle('A1:' . $lastColLetter . '1')->getFont()->setBold(true)->setSize(14);
$sheet->getStyle('A1:' . $lastColLetter . '1')->getAlignment()->setHorizontal(Alignment::HORIZONTAL_CENTER);

$sheet->setCellValue('A2', 'Exportdatum: ' . date('d.m.Y H:i') . ' | Mandant: ' . (defined('Epirent_Mandant') ? Epirent_Mandant : ''));
$sheet->mergeCells('A2:' . $lastColLetter . '2');
$sheet->getStyle('A2:' . $lastColLetter . '2')->getAlignment()->setHorizontal(Alignment::HORIZONTAL_CENTER);

$headerRow = 4;
for ($i=0; $i<$colCount; $i++) {
    $addr = Coordinate::stringFromColumnIndex($i+1) . $headerRow;
    $sheet->setCellValue($addr, $cols[$i]);
    $sheet->getStyle($addr)->getFont()->setBold(true);
    $sheet->getStyle($addr)->getAlignment()->setHorizontal(Alignment::HORIZONTAL_CENTER);
    $sheet->getColumnDimension(Coordinate::stringFromColumnIndex($i+1))->setAutoSize(true);
}

$rowIdx = $headerRow + 1;
foreach ($pivotRows as $r) {
    $c = 1;
    $sheet->setCellValueExplicit(Coordinate::stringFromColumnIndex($c++).$rowIdx, (int)$r['product_pk'], DataType::TYPE_NUMERIC);
    $sheet->setCellValueExplicit(Coordinate::stringFromColumnIndex($c++).$rowIdx, (int)$r['product_no'], DataType::TYPE_NUMERIC);
    $sheet->setCellValue(Coordinate::stringFromColumnIndex($c++).$rowIdx, (string)$r['title']);

    $sheet->setCellValueExplicit(Coordinate::stringFromColumnIndex($c++).$rowIdx, (int)$r['peak_direct'], DataType::TYPE_NUMERIC);
    $sheet->setCellValueExplicit(Coordinate::stringFromColumnIndex($c++).$rowIdx, (int)$r['peak_incl'], DataType::TYPE_NUMERIC);

    $sheet->setCellValueExplicit(Coordinate::stringFromColumnIndex($c).$rowIdx, (float)$r['total_direct'], DataType::TYPE_NUMERIC);
    $sheet->getStyle(Coordinate::stringFromColumnIndex($c).$rowIdx)->getNumberFormat()->setFormatCode('#,##0.00 [$€-de-DE]');
    $c++;

    $sheet->setCellValueExplicit(Coordinate::stringFromColumnIndex($c).$rowIdx, (float)$r['total_incl'], DataType::TYPE_NUMERIC);
    $sheet->getStyle(Coordinate::stringFromColumnIndex($c).$rowIdx)->getNumberFormat()->setFormatCode('#,##0.00 [$€-de-DE]');
    $c++;

    foreach ($years as $y) {
        $d = (float)$r['years'][$y]['direct'];
        $iVal = (float)$r['years'][$y]['incl'];

        $sheet->setCellValueExplicit(Coordinate::stringFromColumnIndex($c).$rowIdx, $d, DataType::TYPE_NUMERIC);
        $sheet->getStyle(Coordinate::stringFromColumnIndex($c).$rowIdx)->getNumberFormat()->setFormatCode('#,##0.00 [$€-de-DE]');
        $c++;

        $sheet->setCellValueExplicit(Coordinate::stringFromColumnIndex($c).$rowIdx, $iVal, DataType::TYPE_NUMERIC);
        $sheet->getStyle(Coordinate::stringFromColumnIndex($c).$rowIdx)->getNumberFormat()->setFormatCode('#,##0.00 [$€-de-DE]');
        $c++;
    }

    $rowIdx++;
}

$sheet->setAutoFilter("A{$headerRow}:{$lastColLetter}{$headerRow}");
$sheet->freezePane("A" . ($headerRow + 1));

// Save
$writer = new Xlsx($spreadsheet);
$writer->save($excelFilePath);

/* =========================
   4) HTML Ausgabe
   ========================= */
?>
<!DOCTYPE html>
<html lang="de">
<head>
    <meta charset="utf-8" />
    <meta http-equiv="X-UA-Compatible" content="IE=edge" />
    <meta name="viewport" content="width=device-width, initial-scale=1, shrink-to-fit=no" />
    <title>ROI – Umsatz pro Artikel / Jahr</title>

    <link href="css/styles.css" rel="stylesheet" />
    <link href="https://cdn.datatables.net/1.10.20/css/dataTables.bootstrap4.min.css" rel="stylesheet" crossorigin="anonymous" />

    <script src="js/jquery-3.5.1.min.js"></script>
    <script src="https://kit.fontawesome.com/93d71de8bc.js" crossorigin="anonymous"></script>

    <!-- Bootstrap -->
    <script src="https://cdn.jsdelivr.net/npm/bootstrap@4.5.3/dist/js/bootstrap.bundle.min.js" crossorigin="anonymous"></script>

    <!-- DataTables -->
    <script src="https://cdn.datatables.net/1.10.20/js/jquery.dataTables.min.js" crossorigin="anonymous"></script>
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    <!-- Chart.js -->
    <script src="https://cdn.jsdelivr.net/npm/chart.js@4.4.1/dist/chart.umd.min.js" crossorigin="anonymous"></script>

    <style>
        .kpi-updated { font-size: .82rem; opacity: .85; }
        .mono { font-family: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, "Liberation Mono", "Courier New", monospace; }
        .btn-xs { padding:.15rem .4rem; font-size:.78rem; }
        .nowrap { white-space: nowrap; }
    </style>

    <script>
        $(function () {
            $('#layoutSidenav_nav').load('../sources/getSidenav.php');
            $('#footerholder').load('../sources/getFooter.php');
        });
    </script>
</head>

<body class="sb-nav-fixed">
<nav class="sb-topnav navbar navbar-expand navbar-dark bg-dark">
    <a class="navbar-brand" href="index.php">Epi Webview</a>
    <button class="btn btn-link btn-sm order-1 order-lg-0" id="sidebarToggle"><i class="fas fa-bars"></i></button>
</nav>

<div id="layoutSidenav">
    <div id="layoutSidenav_nav"></div>
    <div id="layoutSidenav_content">
        <main>
            <div class="container-fluid">
                <h1 class="mt-4">ROI</h1>
                <ol class="breadcrumb mb-4">
                    <li class="breadcrumb-item active">Umsatz / Peak / Histogramm pro Artikel</li>
                </ol>

                <div class="card mb-4">
                    <div class="card-header d-flex justify-content-between align-items-center">
                        <div><i class="fas fa-table mr-1"></i> Pivot: Artikel × Rechnungsjahr</div>
                        <a class="btn btn-sm btn-success" href="<?php echo htmlspecialchars($excelDownloadUrl); ?>">
                            <i class="fas fa-file-excel"></i> Export nach Excel
                        </a>
                    </div>
                    <div class="card-body">
                        <div class="table-responsive">
                            <table class="table table-bordered" id="pivotTable" width="100%" cellspacing="0">
                                <thead>
                                <tr>
                                    <th class="nowrap">Produkt-PK</th>
                                    <th class="nowrap">Artikel-Nr</th>
                                    <th>Artikel</th>
                                    <th class="nowrap">Peak</th>
                                    <th class="nowrap">Summe</th>
                                    <?php foreach ($years as $y): ?>
                                        <th class="nowrap"><?php echo (int)$y; ?></th>
                                    <?php endforeach; ?>
                                    <th class="nowrap">Histogramm</th>
                                </tr>
                                </thead>
                                <tbody>
                                <?php foreach ($pivotRows as $r): ?>
                                    <?php
                                        $peakDirect = (int)$r['peak_direct'];
                                        $peakIncl   = (int)$r['peak_incl'];

                                        $histDirectB64 = base64Json($r['hist_direct']);
                                        $histInclB64   = base64Json($r['hist_incl']);

                                        $sumDirect = (float)$r['total_direct'];
                                        $sumIncl   = (float)$r['total_incl'];
                                    ?>
                                    <tr>
                                        <td class="mono"><?php echo (int)$r['product_pk']; ?></td>
                                        <td class="mono"><?php echo (int)$r['product_no']; ?></td>
                                        <td><?php echo htmlspecialchars((string)$r['title']); ?></td>

                                        <td class="nowrap">
                                            <?php
                                                echo $peakDirect;
                                                echo ' <span class="text-muted">(' . $peakIncl . ')</span>';
                                            ?>
                                        </td>

                                        <td class="nowrap">
                                            <?php
                                                echo formatEuro($sumDirect);
                                                echo ' <span class="text-muted">(' . formatEuro($sumIncl) . ')</span>';
                                            ?>
                                        </td>

                                        <?php foreach ($years as $y): ?>
                                            <?php
                                                $d = (float)$r['years'][$y]['direct'];
                                                $iVal = (float)$r['years'][$y]['incl'];
                                            ?>
                                            <td class="nowrap">
                                                <?php echo formatEuro($d); ?>
                                                <span class="text-muted">(<?php echo formatEuro($iVal); ?>)</span>
                                            </td>
                                        <?php endforeach; ?>

                                        <td class="nowrap">
                                            <button
                                                class="btn btn-outline-primary btn-xs js-hist"
                                                data-title="<?php echo htmlspecialchars((string)$r['title']); ?>"
                                                data-hist="<?php echo htmlspecialchars($histDirectB64); ?>"
                                                data-peak="<?php echo (int)$peakDirect; ?>"
                                                data-mode="direct">
                                                Histogramm
                                            </button>

                                            <button
                                                class="btn btn-outline-secondary btn-xs js-hist"
                                                data-title="<?php echo htmlspecialchars((string)$r['title']); ?>"
                                                data-hist="<?php echo htmlspecialchars($histInclB64); ?>"
                                                data-peak="<?php echo (int)$peakIncl; ?>"
                                                data-mode="incl">
                                                Histogramm inkl. Bundle
                                            </button>
                                        </td>
                                    </tr>
                                <?php endforeach; ?>
                                </tbody>
                            </table>
                            <small class="text-muted">
                                Jahr-Zuordnung Umsatz: <span class="mono">invoice_date</span> (Rechnungsdatum). Peak/Histogramm: Zeitraum <span class="mono">date_start..date_end</span>.
                                Werte in Klammern = inkl. Bundle-Anteil.
                            </small>
                        </div>
                    </div>
                </div>

                <div class="card mb-4">
                    <div class="card-header">
                        <i class="fas fa-list mr-1"></i> Debug: verarbeitete Mietpositionen
                    </div>
                    <div class="card-body">
                        <div class="table-responsive">
                            <table class="table table-bordered" id="detailTable" width="100%" cellspacing="0">
                                <thead>
                                <tr>
                                    <th>Jahr</th>
                                    <th>Invoice</th>
                                    <th>Rechnungsdatum</th>
                                    <th>Quelle</th>
                                    <th>Chapter</th>
                                    <th>Produkt-PK</th>
                                    <th>Artikel-Nr</th>
                                    <th>Artikel</th>
                                    <th>Start</th>
                                    <th>Ende</th>
                                    <th>Menge</th>
                                    <th>Umsatz netto</th>
                                </tr>
                                </thead>
                                <tbody>
                                <?php foreach ($rows as $r): ?>
                                    <tr>
                                        <td><?php echo (int)$r['year']; ?></td>
                                        <td class="mono"><?php echo (int)$r['invoice_pk']; ?></td>
                                        <td class="mono"><?php echo htmlspecialchars((string)$r['invoice_date']); ?></td>
                                        <td><?php echo htmlspecialchars((string)$r['source']); ?></td>
                                        <td class="mono"><?php echo (int)$r['chapter_id']; ?></td>
                                        <td class="mono"><?php echo (int)$r['product_pk']; ?></td>
                                        <td class="mono"><?php echo (int)$r['product_no']; ?></td>
                                        <td><?php echo htmlspecialchars((string)$r['title']); ?></td>
                                        <td class="mono"><?php echo htmlspecialchars((string)$r['date_start']); ?></td>
                                        <td class="mono"><?php echo htmlspecialchars((string)$r['date_end']); ?></td>
                                        <td class="mono"><?php echo htmlspecialchars((string)$r['qty']); ?></td>
                                        <td class="nowrap"><?php echo formatEuro((float)$r['revenue_net']); ?></td>
                                    </tr>
                                <?php endforeach; ?>
                                </tbody>
                            </table>
                            <small class="text-muted">
                                Wenn ein Artikel “ohne Kapitel” fehlt, muss er hier als Quelle <b>direct</b> auftauchen.
                            </small>
                        </div>
                    </div>
                </div>

            </div>
        </main>
        <div id="footerholder"></div>
    </div>
</div>

<!-- Histogram Modal -->
<div class="modal fade" id="histModal" tabindex="-1" role="dialog" aria-hidden="true">
    <div class="modal-dialog modal-lg" role="document">
        <div class="modal-content">
            <div class="modal-header">
                <h5 class="modal-title">Histogramm</h5>
                <button type="button" class="close" data-dismiss="modal" aria-label="Close">
                    <span aria-hidden="true">&times;</span>
                </button>
            </div>
            <div class="modal-body">
                <canvas id="histChart" height="140"></canvas>
                <div class="mt-2 text-muted">
                    X-Achse: gleichzeitig vermietete Stückzahl (1..Peak) &nbsp;|&nbsp; Y-Achse: Tage
                </div>
            </div>
        </div>
    </div>
</div>

<script>
let histChart = null;

function decodeB64Json(b64) {
    try {
        const json = atob(b64);
        return JSON.parse(json);
    } catch (e) {
        return {};
    }
}

function openHistogram(title, mode, peak, histObj) {
    const labels = [];
    const data = [];
    const p = parseInt(peak || 0, 10);

    for (let i = 1; i <= p; i++) {
        labels.push(String(i));
        data.push(histObj[String(i)] ? parseInt(histObj[String(i)], 10) : 0);
    }

    $('#histModal .modal-title').text(`${title} – ${mode === 'incl' ? 'inkl. Bundle' : 'ohne Bundle'}`);

    const ctx = document.getElementById('histChart');
    if (histChart) {
        histChart.destroy();
        histChart = null;
    }

    histChart = new Chart(ctx, {
        type: 'bar',
        data: {
            labels,
            datasets: [{
                label: 'Tage',
                data
            }]
        },
        options: {
            responsive: true,
            animation: false,
            scales: {
                y: {
                    beginAtZero: true,
                    ticks: { precision: 0 }
                }
            }
        }
    });

    $('#histModal').modal('show');
}

$(function() {
    $('#pivotTable').DataTable({ pageLength: 50, order: [[4,'desc']] });
    $('#detailTable').DataTable({ pageLength: 50, order: [[1,'desc']] });

    $(document).on('click', '.js-hist', function() {
        const title = $(this).data('title') || '';
        const mode  = $(this).data('mode') || 'direct';
        const peak  = $(this).data('peak') || 0;
        const b64   = $(this).data('hist') || '';
        const histObj = decodeB64Json(b64);
        openHistogram(title, mode, peak, histObj);
    });
});
</script>

</body>
</html>