<?php
declare(strict_types=1);

ini_set('display_errors', '1');
error_reporting(E_ALL);
session_start();

$loggedIn = isset($_SESSION['user_id']);
$pageTitle = 'Mond-Stern-Bedeckungen - AstroTools';
$bodyClass = 'occ-page';
$headerIntroPre = '';
$headerIntroTitle = '';
$headerIntroSub = '';

function h(?string $value): string
{
    return htmlspecialchars((string)$value, ENT_QUOTES, 'UTF-8');
}

function buildStarLabel(array $row): string
{
    $proper = trim((string)($row['proper'] ?? ''));
    if ($proper !== '') {
        return $proper;
    }

    $bf = trim((string)($row['bf'] ?? ''));
    if ($bf !== '') {
        return $bf;
    }

    $hip = isset($row['hip']) ? (int)$row['hip'] : 0;
    if ($hip > 0) {
        return 'HIP ' . $hip;
    }

    return 'Unbenannter Stern';
}

function runPythonApi(string $scriptPath, string $action, array $arguments): array
{
    $pythonCandidates = ['/usr/bin/python', '/usr/bin/python3', 'python3', 'python'];
    $escapedArguments = [escapeshellarg($scriptPath), escapeshellarg($action)];

    foreach ($arguments as $argument) {
        $escapedArguments[] = escapeshellarg((string)$argument);
    }

    $lastError = 'Python konnte nicht ausgeführt werden.';
    $debugOutput = [];

    foreach ($pythonCandidates as $pythonBinary) {
        $command = $pythonBinary . ' ' . implode(' ', $escapedArguments) . ' 2>&1';
        $output = [];
        $resultCode = 0;
        exec($command, $output, $resultCode);

        $joined = trim(implode("\n", $output));
        $debugOutput = $output;

        if ($resultCode !== 0) {
            $lastError = $joined !== '' ? $joined : ('Fehlercode ' . $resultCode . ' bei ' . $pythonBinary);
            continue;
        }

        $decoded = json_decode($joined, true);
        if (!is_array($decoded)) {
            $lastError = $joined !== '' ? 'Python-Ausgabe war kein gültiges JSON.' : 'Python lieferte keine Ausgabe zurück.';
            continue;
        }

        if (!($decoded['ok'] ?? false)) {
            return [
                'ok' => false,
                'error' => (string)($decoded['error'] ?? 'Unbekannter Python-Fehler'),
                'debug' => $joined,
            ];
        }

        return ['ok' => true, 'data' => $decoded];
    }

    return [
        'ok' => false,
        'error' => $lastError,
        'debug' => implode("\n", $debugOutput),
    ];
}

$defaultLocation = null;
$pdo = null;
$pageError = null;
$pageLocation = null;
$detailMapStars = [];
$constellationLines = [];
$detailMapCatalogLimit = 8.0;
$isAjax = isset($_POST['ajax']) && (string)$_POST['ajax'] === '1';

try {
    $config = require __DIR__ . '/../config/database.php';
    $dsn = sprintf(
        'mysql:host=%s;dbname=%s;charset=%s',
        $config['host'],
        $config['dbname'],
        $config['charset'] ?? 'utf8mb4'
    );

    $pdo = new PDO(
        $dsn,
        $config['user'],
        $config['pass'],
        [
            PDO::ATTR_ERRMODE => PDO::ERRMODE_EXCEPTION,
            PDO::ATTR_DEFAULT_FETCH_MODE => PDO::FETCH_ASSOC,
        ]
    );

    if ($loggedIn && isset($_SESSION['user_id'])) {
        $stmtLocation = $pdo->prepare(
            'SELECT id, name, latitude, longitude, elevation, timezone
             FROM app_user_locations
             WHERE user_id = ? AND is_default = 1
             LIMIT 1'
        );
        $stmtLocation->execute([(int)$_SESSION['user_id']]);
        $defaultLocation = $stmtLocation->fetch() ?: null;
    }
} catch (Throwable $exception) {
    $pageError = $exception->getMessage();
}

if (!empty($defaultLocation) && is_array($defaultLocation)) {
    $pageLocation = [
        'name' => (string)($defaultLocation['name'] ?? ''),
        'latitude' => isset($defaultLocation['latitude']) ? (float)$defaultLocation['latitude'] : null,
        'longitude' => isset($defaultLocation['longitude']) ? (float)$defaultLocation['longitude'] : null,
        'elevation' => isset($defaultLocation['elevation']) && $defaultLocation['elevation'] !== null ? (float)$defaultLocation['elevation'] : 0.0,
        'timezone' => (string)($defaultLocation['timezone'] ?? 'Europe/Berlin'),
    ];
}

$timezoneName = $pageLocation['timezone'] ?? 'Europe/Berlin';
try {
    $timezone = new DateTimeZone($timezoneName);
} catch (Throwable $exception) {
    $timezoneName = 'Europe/Berlin';
    $timezone = new DateTimeZone($timezoneName);
}

$todayLocal = (new DateTimeImmutable('now', $timezone))->format('Y-m-d');
$selectedDate = isset($_POST['date']) && preg_match('/^\d{4}-\d{2}-\d{2}$/', (string)$_POST['date'])
    ? (string)$_POST['date']
    : $todayLocal;

$selectedMag = isset($_POST['mag']) ? (float)$_POST['mag'] : 3.0;
$selectedMag = max(1.0, min(6.0, $selectedMag));
$selectedMag = round($selectedMag, 1);

if (!$isAjax && $pageError === null && $pdo instanceof PDO && $pageLocation !== null && $pageLocation['latitude'] !== null && $pageLocation['longitude'] !== null) {
    try {
        $stmtDetailMap = $pdo->query(
            "SELECT `hip`, `proper`, `bf`, `con`, `mag`, `ra`, `dec`, `dist`
             FROM `star_hipparcos`
             WHERE `mag` IS NOT NULL
               AND `ra` IS NOT NULL
               AND `dec` IS NOT NULL
               AND `mag` <= 8.0
             ORDER BY `mag` ASC, `proper` ASC, `bf` ASC, `hip` ASC"
        );

        foreach ($stmtDetailMap->fetchAll() as $row) {
            $detailMapStars[] = [
                'hip' => isset($row['hip']) ? (int)$row['hip'] : 0,
                'label' => buildStarLabel($row),
                'constellation' => trim((string)($row['con'] ?? '')),
                'mag' => isset($row['mag']) ? (float)$row['mag'] : null,
                'ra' => isset($row['ra']) ? (float)$row['ra'] : null,
                'dec' => isset($row['dec']) ? (float)$row['dec'] : null,
                'distLy' => isset($row['dist']) && $row['dist'] !== null && (float)$row['dist'] > 0.0
                    ? (float)$row['dist'] * 3.26156
                    : 1000.0,
            ];
        }

        $stmtLines = $pdo->query(
            "SELECT
                cl.`id` AS line_id,
                clp.`point_index`,
                sh.`ra` AS ra_hours,
                sh.`dec` AS dec_deg
             FROM `constellation_lines` cl
             INNER JOIN `constellation_line_points` clp
                ON clp.`line_id` = cl.`id`
             INNER JOIN `star_hipparcos` sh
                ON sh.`hip` = clp.`hip_number`
             WHERE sh.`ra` IS NOT NULL
               AND sh.`dec` IS NOT NULL
             ORDER BY cl.`id`, clp.`point_index`"
        );

        foreach ($stmtLines->fetchAll() as $row) {
            $lineId = (int)$row['line_id'];
            $constellationLines[$lineId][] = [
                'ra' => isset($row['ra_hours']) ? (float)$row['ra_hours'] : null,
                'dec' => isset($row['dec_deg']) ? (float)$row['dec_deg'] : null,
            ];
        }
    } catch (Throwable $exception) {
        $pageError = $exception->getMessage();
        $detailMapStars = [];
        $constellationLines = [];
    }
}

if ($isAjax) {
    header('Content-Type: application/json; charset=utf-8');

    if ($pageLocation === null || $pageLocation['latitude'] === null || $pageLocation['longitude'] === null) {
        echo json_encode([
            'ok' => false,
            'error' => 'Kein Standard-Standort gesetzt. Bitte zuerst in den Einstellungen einen Standard-Standort hinterlegen.',
        ], JSON_UNESCAPED_UNICODE | JSON_UNESCAPED_SLASHES);
        exit;
    }

    if ($pageError !== null || !($pdo instanceof PDO)) {
        echo json_encode([
            'ok' => false,
            'error' => $pageError ?? 'Die Datenbank ist nicht verfuegbar.',
        ], JSON_UNESCAPED_UNICODE | JSON_UNESCAPED_SLASHES);
        exit;
    }

    try {
        $stmtStars = $pdo->prepare(
            "SELECT `hip`, `proper`, `bf`, `con`, `mag`, `ra`, `dec`, `dist`
             FROM `star_hipparcos`
             WHERE `mag` IS NOT NULL
               AND `ra` IS NOT NULL
               AND `dec` IS NOT NULL
               AND `mag` <= :max_mag
             ORDER BY `mag` ASC, `proper` ASC, `bf` ASC, `hip` ASC"
        );
        $stmtStars->execute([':max_mag' => $selectedMag]);

        $stars = [];
        foreach ($stmtStars->fetchAll() as $row) {
            $stars[] = [
                'hip' => isset($row['hip']) ? (int)$row['hip'] : 0,
                'label' => buildStarLabel($row),
                'constellation' => trim((string)($row['con'] ?? '')),
                'mag' => isset($row['mag']) ? (float)$row['mag'] : 99.0,
                'ra' => isset($row['ra']) ? (float)$row['ra'] : 0.0,
                'dec' => isset($row['dec']) ? (float)$row['dec'] : 0.0,
                'distLy' => isset($row['dist']) && $row['dist'] !== null && (float)$row['dist'] > 0.0
                    ? (float)$row['dist'] * 3.26156
                    : 1000.0,
            ];
        }

        $starCount = count($stars);
        $tempFile = tempnam(sys_get_temp_dir(), 'occult_stars_');
        if ($tempFile === false) {
            throw new RuntimeException('Temporäre Sterndatei konnte nicht angelegt werden.');
        }

        try {
            file_put_contents($tempFile, json_encode($stars, JSON_UNESCAPED_UNICODE | JSON_UNESCAPED_SLASHES | JSON_THROW_ON_ERROR));

            $pythonResult = runPythonApi(
                __DIR__ . '/py/api.py',
                'moon_star_occultations',
                [
                    (string)$pageLocation['latitude'],
                    (string)$pageLocation['longitude'],
                    (string)$pageLocation['elevation'],
                    $selectedDate,
                    $timezoneName,
                    $tempFile,
                ]
            );

            if (!$pythonResult['ok']) {
                echo json_encode([
                    'ok' => false,
                    'error' => $pythonResult['error'] ?? 'Unbekannter Python-Fehler',
                    'debug' => $pythonResult['debug'] ?? null,
                ], JSON_UNESCAPED_UNICODE | JSON_UNESCAPED_SLASHES);
                exit;
            }

            echo json_encode([
                'ok' => true,
                'star_count' => $starCount,
                'results' => $pythonResult['data']['results'] ?? [],
                'selected_date' => $selectedDate,
                'selected_mag' => $selectedMag,
            ], JSON_UNESCAPED_UNICODE | JSON_UNESCAPED_SLASHES);
            exit;
        } finally {
            if (is_file($tempFile)) {
                @unlink($tempFile);
            }
        }
    } catch (Throwable $exception) {
        echo json_encode([
            'ok' => false,
            'error' => $exception->getMessage(),
        ], JSON_UNESCAPED_UNICODE | JSON_UNESCAPED_SLASHES);
        exit;
    }
}

require __DIR__ . '/header.php';

if (!empty($currentLocation) && is_array($currentLocation)) {
    $pageLocation = [
        'name' => (string)($currentLocation['name'] ?? ''),
        'latitude' => isset($currentLocation['latitude']) ? (float)$currentLocation['latitude'] : null,
        'longitude' => isset($currentLocation['longitude']) ? (float)$currentLocation['longitude'] : null,
        'elevation' => isset($currentLocation['elevation']) && $currentLocation['elevation'] !== null ? (float)$currentLocation['elevation'] : 0.0,
        'timezone' => (string)($currentLocation['timezone'] ?? 'Europe/Berlin'),
    ];
}
?>

<script src="js/astronomy.browser.min.js"></script>

<div class="occult-tool">
<?php if ($pageLocation === null || $pageLocation['latitude'] === null || $pageLocation['longitude'] === null): ?>
    <section class="card occult-card">
        <h2>Kein Standard-Standort gesetzt</h2>
        <p class="hint">
            Fuer die Berechnung wird der Standard-Standort aus der Datenbank verwendet.
            Bitte wähle in den <a href="settings.php">Einstellungen</a> einen Standard-Standort aus.
        </p>
    </section>
<?php elseif ($pageError !== null): ?>
    <section class="card occult-card">
        <h2>Datenbank nicht verfuegbar</h2>
        <p class="hint">Die Sterndaten konnten nicht geladen werden.</p>
        <p class="hint">Technischer Hinweis: <?= h($pageError) ?></p>
    </section>
<?php else: ?>
    <section class="card occult-card">
        <div class="occult-head">
            <div class="occult-head-item occult-head-location">
                <span class="occult-label">Standort</span>
                <strong><?= h($pageLocation['name']) ?></strong>
                <span><?= number_format((float)$pageLocation['latitude'], 4, '.', '') ?>&deg; / <?= number_format((float)$pageLocation['longitude'], 4, '.', '') ?>&deg;</span>
                <span><?= h($timezoneName) ?></span>
            </div>
            <div class="occult-head-item">
                <span class="occult-label">Berechnung</span>
                <form method="post" class="occult-date-picker-row" id="occultForm">
                    <button type="button" class="btn btn-secondary btn-sm" id="occultPrevDay">Tag -</button>
                    <label for="occultDatePicker" class="occult-select-label">Datum</label>
                    <input type="date" id="occultDatePicker" class="occult-date-input" name="date" value="<?= h($selectedDate) ?>">
                    <button type="button" class="btn btn-secondary btn-sm" id="occultTodayBtn">Heute</button>
                    <button type="button" class="btn btn-secondary btn-sm" id="occultNextDay">Tag +</button>
                    <label for="occultMagSelect" class="occult-select-label">bis</label>
                    <select id="occultMagSelect" class="satpass-select occult-select" name="mag">
                        <?php foreach ([2.0, 2.5, 3.0, 3.5, 4.0, 4.5, 5.0, 5.5, 6.0] as $magOption): ?>
                            <option value="<?= h(number_format($magOption, 1, '.', '')) ?>"<?= abs($selectedMag - $magOption) < 0.01 ? ' selected' : '' ?>>
                                <?= h(number_format($magOption, 1, ',', '')) ?> mag
                            </option>
                        <?php endforeach; ?>
                    </select>
                    <input type="hidden" name="calculate" value="1">
                    <button type="submit" class="btn btn-primary btn-sm">Berechnen</button>
                    <button type="button" class="btn btn-secondary btn-sm" id="occultWeekBtn">7 Tage</button>
                    <button type="button" class="btn btn-secondary btn-sm" id="occultMonthBtn">Monat</button>
                </form>
                <span class="hint">Die Berechnung läuft im Hintergrund. Hoehere Grenzgrössen brauchen deutlich länger.</span>
            </div>
        </div>
        <div class="occult-status occult-status-hidden" id="occultSubmitStatus" hidden>
            <span class="occult-spinner occult-spinner-visible" aria-hidden="true"></span>
            <span>Berechnung laeuft... Die Auswertung kann je nach Grenzgrösse etwas dauern.</span>
        </div>
    </section>

    <div id="occultResults">
        <section class="card occult-card">
            <h2>Bereit zur Berechnung</h2>
            <p class="hint">
                Wähle Datum und Grenzgröße und starte die
                Auswertung mit dem Button.
            </p>
        </section>
    </div>

    <section class="card occult-card occult-detail-card" id="occultDetailCard" hidden>
        <div class="occult-detail-head">
            <div>
                <span class="occult-label">Detailansicht</span>
                <strong id="occultDetailTitle">Bedeckungskarte</strong>
            </div>
            <div class="occult-detail-head-controls">
                <div class="occult-detail-meta" id="occultDetailMeta">Feld 5 x 5 Grad, Mond im Zentrum</div>
                <div class="occult-map-size-row">
                    <label for="occultMapSizeSelect" class="occult-select-label">Kartengrösse</label>
                    <select id="occultMapSizeSelect" class="satpass-select occult-select">
                        <option value="5" selected>5 x 5 Grad</option>
                        <option value="10">10 x 10 Grad</option>
                        <option value="15">15 x 15 Grad</option>
                    </select>
                    <button type="button" class="btn btn-secondary btn-sm" id="occultInvertBtn">Invertiert</button>
                </div>
            </div>
        </div>
        <div class="occult-detail-layout">
            <canvas id="occultDetailCanvas" width="420" height="420"></canvas>
            <div class="occult-detail-info" id="occultDetailInfo"></div>
        </div>
    </section>
<?php endif; ?>
</div>

<div class="occult-submit-overlay" id="occultSubmitOverlay" hidden>
    <div class="occult-submit-panel">
        <div class="occult-submit-title">Berechnung laeuft</div>
        <div class="occult-submit-row">
            <span class="occult-spinner occult-spinner-visible" aria-hidden="true"></span>
            <span class="occult-submit-text">Die serverseitige Python-Auswertung wird im Hintergrund ausgefuehrt. Die Seite bleibt dabei sichtbar.</span>
        </div>
        <div class="occult-submit-progress">
            <div class="occult-submit-progress-head">
                <span>Fortschritt</span>
                <span class="occult-submit-progress-value" id="occultSubmitProgressValue">0 %</span>
            </div>
            <div class="occult-submit-progress-bar" aria-hidden="true">
                <div class="occult-submit-progress-fill" id="occultSubmitProgressFill"></div>
            </div>
            <div class="occult-submit-progress-note">Geschätzter Fortschritt während der laufenden Serverberechnung.</div>
        </div>
    </div>
</div>

<script>
(function () {
    const Astronomy = window.Astronomy;
    const form = document.getElementById('occultForm');
    const status = document.getElementById('occultSubmitStatus');
    const overlay = document.getElementById('occultSubmitOverlay');
    const results = document.getElementById('occultResults');
    const progressValue = document.getElementById('occultSubmitProgressValue');
    const progressFill = document.getElementById('occultSubmitProgressFill');
    const prevDayBtn = document.getElementById('occultPrevDay');
    const nextDayBtn = document.getElementById('occultNextDay');
    const todayBtn = document.getElementById('occultTodayBtn');
    const weekBtn = document.getElementById('occultWeekBtn');
    const monthBtn = document.getElementById('occultMonthBtn');
    const datePicker = document.getElementById('occultDatePicker');
    const magSelect = document.getElementById('occultMagSelect');
    const detailCardEl = document.getElementById('occultDetailCard');
    const detailCanvasEl = document.getElementById('occultDetailCanvas');
    const detailTitleEl = document.getElementById('occultDetailTitle');
    const detailMetaEl = document.getElementById('occultDetailMeta');
    const detailInfoEl = document.getElementById('occultDetailInfo');
    const mapSizeSelectEl = document.getElementById('occultMapSizeSelect');
    const invertBtn = document.getElementById('occultInvertBtn');
    const SITE_LOCATION = <?= json_encode($pageLocation, JSON_UNESCAPED_SLASHES | JSON_UNESCAPED_UNICODE) ?>;
    const DETAIL_MAP_STARS = <?= json_encode($detailMapStars, JSON_UNESCAPED_SLASHES | JSON_UNESCAPED_UNICODE) ?>;
    const CONSTELLATION_LINES = <?= json_encode(array_values($constellationLines), JSON_UNESCAPED_SLASHES) ?>;
    const DETAIL_MAP_CATALOG_LIMIT = <?= json_encode($detailMapCatalogLimit, JSON_UNESCAPED_SLASHES) ?>;
    const DETAIL_MAP_LABEL_LIMIT = 5.0;
    const STAR_BODIES = ['Star1', 'Star2', 'Star3', 'Star4', 'Star5', 'Star6', 'Star7', 'Star8'];
    const OBSERVER = new Astronomy.Observer(
        Number(SITE_LOCATION.latitude),
        Number(SITE_LOCATION.longitude),
        Number(SITE_LOCATION.elevation || 0)
    );
    const TIME_FMT = new Intl.DateTimeFormat('de-DE', {
        timeZone: SITE_LOCATION.timezone,
        hour: '2-digit',
        minute: '2-digit'
    });
    const STATE = {
        results: [],
        selectedEventIndex: null,
        mapSizeDeg: mapSizeSelectEl ? Number(mapSizeSelectEl.value || 5) : 5,
        invertMap: false
    };

    if (!form || !status || !overlay || !results || !progressValue || !progressFill) {
        return;
    }

    function escapeHtml(value) {
        return String(value)
            .replace(/&/g, '&amp;')
            .replace(/</g, '&lt;')
            .replace(/>/g, '&gt;')
            .replace(/"/g, '&quot;')
            .replace(/'/g, '&#039;');
    }

    function formatTimeBlock(timeData) {
        if (!timeData || !timeData.local_time) {
            return '&mdash;';
        }
        if (timeData.local_date) {
            return `${escapeHtml(timeData.local_time)} Uhr (${escapeHtml(timeData.local_date)})`;
        }
        return `${escapeHtml(timeData.local_time)} Uhr`;
    }

    function formatDuration(seconds) {
        if (!Number.isFinite(seconds) || seconds <= 0) {
            return '&mdash;';
        }
        const minutes = Math.round(seconds / 60);
        const hours = Math.floor(minutes / 60);
        const rest = minutes % 60;
        if (hours > 0) {
            return `${hours} h ${String(rest).padStart(2, '0')} min`;
        }
        return `${rest} min`;
    }

    function formatDateLabel(dateString) {
        const utcMid = new Date(`${dateString}T12:00:00Z`);
        return new Intl.DateTimeFormat('de-DE', {
            timeZone: SITE_LOCATION.timezone,
            day: '2-digit',
            month: '2-digit',
            year: 'numeric'
        }).format(utcMid);
    }

    function shiftDateString(dateString, days) {
        const date = new Date(`${dateString}T12:00:00Z`);
        date.setUTCDate(date.getUTCDate() + days);
        return date.toISOString().slice(0, 10);
    }

    function getTzParts(date, timeZone) {
        const parts = new Intl.DateTimeFormat('en-GB', {
            timeZone,
            year: 'numeric',
            month: '2-digit',
            day: '2-digit',
            hour: '2-digit',
            minute: '2-digit',
            second: '2-digit',
            hourCycle: 'h23'
        }).formatToParts(date);
        const result = {};
        for (const part of parts) {
            if (part.type !== 'literal') {
                result[part.type] = Number(part.value);
            }
        }
        return result;
    }

    function getTodayDateString() {
        const parts = getTzParts(new Date(), SITE_LOCATION.timezone);
        return `${String(parts.year).padStart(4, '0')}-${String(parts.month).padStart(2, '0')}-${String(parts.day).padStart(2, '0')}`;
    }

    function toEventMillis(timeData) {
        if (!timeData || !timeData.utc_iso) {
            return null;
        }
        const millis = Date.parse(timeData.utc_iso);
        return Number.isFinite(millis) ? millis : null;
    }

    function visibilityClass(key) {
        if (key === 'night') return 'occult-visibility-night';
        if (key === 'twilight') return 'occult-visibility-twilight';
        return 'occult-visibility-day';
    }

    function renderError(message, debug) {
        results.innerHTML = `
            <section class="card occult-card">
                <h2>Berechnung fehlgeschlagen</h2>
                <div class="msg-error">
                    ${escapeHtml(message || 'Unbekannter Fehler')}
                    ${debug ? `<pre>${escapeHtml(debug)}</pre>` : ''}
                </div>
            </section>
        `;
    }

    function renderSuccess(payload) {
        const rows = Array.isArray(payload.results) ? payload.results.map((row) => ({
            ...row,
            ingressMs: toEventMillis(row.ingress),
            maxMs: toEventMillis(row.maximum),
            egressMs: toEventMillis(row.egress)
        })) : [];
        STATE.results = rows;
        STATE.selectedEventIndex = null;
        const dateValues = rows
            .map((row) => row._dateString || '')
            .filter((value) => !!value)
            .sort();
        const rangeStart = payload.range_start || (dateValues.length > 0 ? dateValues[0] : (payload.selected_date || ''));
        const rangeEnd = payload.range_end || (dateValues.length > 0 ? dateValues[dateValues.length - 1] : (payload.selected_date || ''));
        let coveredRangeLabel = 'kein Zeitraum';
        if (rangeStart && rangeEnd) {
            coveredRangeLabel = rangeStart === rangeEnd
                ? formatDateLabel(rangeStart)
                : `${formatDateLabel(rangeStart)} bis ${formatDateLabel(rangeEnd)}`;
        }

        const hasDateColumn = rows.some((row) => !!row._dateString);
        let summaryHtml = `
            <section class="card occult-card">
                <div class="occult-summary">
                    <div class="occult-stat">
                        <span class="occult-label">Gepruefte Sterne</span>
                        <strong>${escapeHtml(payload.star_count ?? 0)}</strong>
                    </div>
                    <div class="occult-stat">
                        <span class="occult-label">Zeitraum</span>
                        <strong>${escapeHtml(coveredRangeLabel)}</strong>
                    </div>
                    <div class="occult-stat">
                        <span class="occult-label">Gefundene Ereignisse</span>
                        <strong>${escapeHtml(rows.length)}</strong>
                    </div>
                </div>
            </section>
        `;

        let tableRows = '';
        if (rows.length === 0) {
            const magSelect = form.querySelector('select[name="mag"]');
            const currentMag = magSelect ? magSelect.value.replace('.', ',') : '';
            tableRows = `
                <tr>
                    <td colspan="9" class="occult-empty">
                        Fuer dieses Datum wurden keine Mond-Stern-Bedeckungen heller als ${escapeHtml(currentMag)} mag gefunden.
                    </td>
                </tr>
            `;
        } else {
            tableRows = rows.map((row, index) => {
                const star = row.star || {};
                const starName = star.constellation
                    ? `${escapeHtml(star.label || 'Unbenannter Stern')} (${escapeHtml(star.constellation)})`
                    : escapeHtml(star.label || 'Unbenannter Stern');
                const visibility = row.visibility || {};
                const dateCell = hasDateColumn ? `<td class="occult-week-date">${escapeHtml(formatDateLabel(row._dateString || payload.selected_date || ''))}</td>` : '';

                return `
                    <tr class="occult-row" data-event-index="${index}">
                        ${dateCell}
                        <td>${starName}</td>
                        <td>${escapeHtml(Number(star.mag || 99).toFixed(2).replace('.', ','))}</td>
                        <td>${formatTimeBlock(row.ingress)}</td>
                        <td>${formatTimeBlock(row.maximum)}</td>
                        <td>${formatTimeBlock(row.egress)}</td>
                        <td>${formatDuration(Number(row.duration_seconds))}</td>
                        <td><span class="occult-visibility ${visibilityClass(visibility.key)}">${escapeHtml(visibility.label || 'Tag')}</span></td>
                        <td>${escapeHtml(Number(row.limb_distance_arcmin || 0).toFixed(2).replace('.', ','))}'</td>
                        <td>${escapeHtml(Number(row.moon_alt_deg || 0).toFixed(1).replace('.', ','))}&deg;</td>
                    </tr>
                `;
            }).join('');
        }

        results.innerHTML = `
            ${summaryHtml}
            <section class="card occult-card">
                <div class="occult-table-wrap">
                    <table class="data-table occult-table">
                        <thead>
                            <tr>
                                ${hasDateColumn ? '<th>Datum</th>' : ''}
                                <th>Stern</th>
                                <th>mag</th>
                                <th>Eintritt</th>
                                <th>Maximum</th>
                                <th>Austritt</th>
                                <th>Dauer</th>
                                <th>Sichtbarkeit</th>
                                <th>Randabstand</th>
                                <th>Mondhoehe</th>
                            </tr>
                        </thead>
                        <tbody>${tableRows}</tbody>
                    </table>
                </div>
            </section>
        `;

        results.querySelectorAll('tr[data-event-index]').forEach((row) => {
            row.addEventListener('click', function () {
                renderOccultationMap(Number(row.dataset.eventIndex));
            });
        });

        if (rows.length > 0) {
            renderOccultationMap(0);
        } else if (detailCardEl) {
            detailCardEl.hidden = true;
        }
    }

    function setEstimatedProgress(value) {
        const safeValue = Math.max(0, Math.min(100, Math.round(value)));
        progressValue.textContent = `${safeValue} %`;
        progressFill.style.width = `${safeValue}%`;
    }

    let isSubmitting = false;
    let progressTimer = null;

    function startEstimatedProgress() {
        if (progressTimer) {
            window.clearInterval(progressTimer);
        }

        let current = 0;
        setEstimatedProgress(current);

        progressTimer = window.setInterval(function () {
            if (current < 20) {
                current += 4;
            } else if (current < 45) {
                current += 2;
            } else if (current < 70) {
                current += 1.2;
            } else if (current < 88) {
                current += 0.5;
            } else if (current < 94) {
                current += 0.2;
            }

            setEstimatedProgress(current);
        }, 300);
    }

    function stopEstimatedProgress(success) {
        if (progressTimer) {
            window.clearInterval(progressTimer);
            progressTimer = null;
        }

        setEstimatedProgress(success ? 100 : 0);
    }

    function setRangeProgress(done, total) {
        if (!total || total <= 0) {
            return;
        }
        setEstimatedProgress((done / total) * 100);
    }

    function angularOffsetDeg(raHours, decDeg, centerRaHours, centerDecDeg) {
        let deltaRaDeg = (raHours - centerRaHours) * 15;
        while (deltaRaDeg > 180) deltaRaDeg -= 360;
        while (deltaRaDeg < -180) deltaRaDeg += 360;
        return {
            xDeg: deltaRaDeg * Math.cos(centerDecDeg * Math.PI / 180),
            yDeg: decDeg - centerDecDeg,
        };
    }

    function starBrightnessFactor(mag) {
        const clamped = Math.max(-1.5, Math.min(8.0, Number(mag)));
        return (8.5 - clamped) / 10.0;
    }

    function magnitudeToRadius(mag, isTarget) {
        const brightness = starBrightnessFactor(mag);
        const baseRadius = 0.7 + brightness * 2.2;
        return isTarget ? baseRadius + 0.8 : baseRadius;
    }

    function drawStarSymbol(ctx, x, y, mag, isTarget) {
        const brightness = starBrightnessFactor(mag);
        const coreRadius = magnitudeToRadius(mag, isTarget);
        const glowRadius = coreRadius * (isTarget ? 3.6 : 2.6);
        const glow = ctx.createRadialGradient(x, y, 0, x, y, glowRadius);
        const isInverted = STATE.invertMap;

        if (isTarget) {
            if (isInverted) {
                glow.addColorStop(0, 'rgba(143, 98, 12, 0.72)');
                glow.addColorStop(0.28, 'rgba(201, 152, 48, 0.38)');
                glow.addColorStop(1, 'rgba(201, 152, 48, 0)');
            } else {
                glow.addColorStop(0, 'rgba(255, 236, 170, 0.95)');
                glow.addColorStop(0.28, 'rgba(255, 214, 111, 0.68)');
                glow.addColorStop(1, 'rgba(255, 214, 111, 0)');
            }
        } else {
            if (isInverted) {
                const glowAlpha = 0.06 + brightness * 0.18;
                glow.addColorStop(0, `rgba(42, 56, 82, ${Math.min(0.68, 0.18 + brightness * 0.38)})`);
                glow.addColorStop(0.35, `rgba(85, 102, 136, ${glowAlpha})`);
                glow.addColorStop(1, 'rgba(85, 102, 136, 0)');
            } else {
                const glowAlpha = 0.12 + brightness * 0.32;
                glow.addColorStop(0, `rgba(232, 239, 255, ${Math.min(0.92, 0.30 + brightness * 0.55)})`);
                glow.addColorStop(0.35, `rgba(190, 208, 255, ${glowAlpha})`);
                glow.addColorStop(1, 'rgba(190, 208, 255, 0)');
            }
        }

        ctx.beginPath();
        ctx.arc(x, y, glowRadius, 0, Math.PI * 2);
        ctx.fillStyle = glow;
        ctx.fill();

        ctx.beginPath();
        ctx.arc(x, y, coreRadius, 0, Math.PI * 2);
        ctx.fillStyle = isInverted
            ? (isTarget ? '#7f5b05' : '#253246')
            : (isTarget ? '#ffe8b0' : '#f5f8ff');
        ctx.fill();

        if (isTarget) {
            ctx.beginPath();
            ctx.arc(x, y, coreRadius + 2.2, 0, Math.PI * 2);
            ctx.strokeStyle = isInverted ? 'rgba(153, 112, 22, 0.85)' : 'rgba(255, 214, 111, 0.85)';
            ctx.lineWidth = 1;
            ctx.stroke();
        }
    }

    function getStarLabelMetrics(ctx, label, isTarget) {
        ctx.save();
        ctx.font = isTarget ? '12px Segoe UI' : '11px Segoe UI';
        const text = String(label);
        const textWidth = ctx.measureText(text).width;
        ctx.restore();

        return {
            text,
            textWidth,
            padX: 4,
            boxH: isTarget ? 18 : 16,
            font: isTarget ? '12px Segoe UI' : '11px Segoe UI',
        };
    }

    function getLabelPlacementOptions(x, y, metrics) {
        const boxW = metrics.textWidth + metrics.padX * 2;
        const boxH = metrics.boxH;

        return [
            { boxX: x + 8, boxY: y - 8, boxW, boxH },
            { boxX: x - boxW - 8, boxY: y - 8, boxW, boxH },
            { boxX: x + 8, boxY: y + 12, boxW, boxH },
            { boxX: x - boxW - 8, boxY: y + 12, boxW, boxH },
            { boxX: x - boxW / 2, boxY: y - 14 - boxH / 2, boxW, boxH },
            { boxX: x - boxW / 2, boxY: y + 16, boxW, boxH },
        ];
    }

    function drawStarLabel(ctx, x, y, label, isTarget, placement) {
        if (!label) {
            return null;
        }

        const metrics = getStarLabelMetrics(ctx, label, isTarget);
        const box = placement || getLabelPlacementOptions(x, y, metrics)[0];

        const isInverted = STATE.invertMap;

        ctx.save();
        ctx.font = metrics.font;
        ctx.textAlign = 'left';
        ctx.textBaseline = 'middle';
        ctx.fillStyle = isInverted
            ? (isTarget ? 'rgba(255, 247, 222, 0.9)' : 'rgba(255, 255, 255, 0.82)')
            : (isTarget ? 'rgba(10, 14, 24, 0.82)' : 'rgba(0, 0, 0, 0.58)');
        ctx.fillRect(box.boxX, box.boxY - box.boxH / 2, box.boxW, box.boxH);
        ctx.fillStyle = isInverted
            ? (isTarget ? '#6d4e00' : 'rgba(26, 34, 52, 0.9)')
            : (isTarget ? '#f0d990' : 'rgba(221,227,245,0.82)');
        ctx.fillText(metrics.text, box.boxX + metrics.padX, box.boxY);
        ctx.restore();

        return {
            left: box.boxX,
            top: box.boxY - box.boxH / 2,
            right: box.boxX + box.boxW,
            bottom: box.boxY + box.boxH / 2,
        };
    }

    function labelBoxesOverlap(a, b, margin) {
        const gap = Number.isFinite(margin) ? margin : 2;
        return !(
            a.right + gap < b.left ||
            a.left > b.right + gap ||
            a.bottom + gap < b.top ||
            a.top > b.bottom + gap
        );
    }

    function getMoonTerminatorInfo(time, moonEq) {
        const sunEq = Astronomy.Equator('Sun', time, OBSERVER, true, true);
        const illum = Astronomy.Illumination('Moon', time);
        const offset = angularOffsetDeg(sunEq.ra, sunEq.dec, moonEq.ra, moonEq.dec);
        const brightSideAngleRad = Math.atan2(-offset.yDeg, -offset.xDeg);
        const phaseFraction = Math.max(0, Math.min(1, Number(illum.phase_fraction ?? 0.5)));

        return {
            phaseFraction,
            brightSideAngleRad
        };
    }

    function drawMoonWithTerminator(ctx, centerX, centerY, radiusPx, terminatorInfo) {
        const phaseFraction = terminatorInfo.phaseFraction;
        const brightSideAngleRad = terminatorInfo.brightSideAngleRad;
        const cosPhase = Math.max(-1, Math.min(1, 2 * phaseFraction - 1));
        const isInverted = STATE.invertMap;
        const baseMoonFill = isInverted ? 'rgba(236, 239, 245, 0.98)' : 'rgba(24, 28, 36, 0.96)';
        const litMoonFill = isInverted ? 'rgba(86, 94, 112, 0.88)' : 'rgba(228, 232, 240, 0.95)';
        const moonStroke = isInverted ? 'rgba(70, 78, 96, 0.75)' : 'rgba(245,248,255,0.72)';

        ctx.save();
        ctx.translate(centerX, centerY);
        ctx.rotate(brightSideAngleRad);

        ctx.beginPath();
        ctx.arc(0, 0, radiusPx, 0, Math.PI * 2);
        ctx.fillStyle = baseMoonFill;
        ctx.fill();

        if (phaseFraction <= 0.001) {
            ctx.lineWidth = 2;
            ctx.strokeStyle = isInverted ? 'rgba(70, 78, 96, 0.55)' : 'rgba(170,180,195,0.35)';
            ctx.stroke();
            ctx.restore();
            return;
        }

        if (phaseFraction >= 0.999) {
            ctx.beginPath();
            ctx.arc(0, 0, radiusPx, 0, Math.PI * 2);
            ctx.fillStyle = litMoonFill;
            ctx.fill();
            ctx.lineWidth = 2;
            ctx.strokeStyle = moonStroke;
            ctx.stroke();
            ctx.restore();
            return;
        }

        ctx.save();
        ctx.beginPath();
        ctx.arc(0, 0, radiusPx, 0, Math.PI * 2);
        ctx.clip();

        for (let y = -radiusPx; y <= radiusPx; y += 1) {
            const chord = Math.sqrt(Math.max(0, radiusPx * radiusPx - y * y));
            const xLeft = -chord;
            const xRight = chord;
            const xTerminator = -cosPhase * chord;
            const litStart = Math.max(xLeft, xTerminator);
            const litWidth = xRight - litStart;
            if (litWidth <= 0) {
                continue;
            }

            ctx.fillStyle = litMoonFill;
            ctx.fillRect(litStart, y, litWidth, 1.2);
        }
        ctx.restore();

        ctx.beginPath();
        ctx.arc(0, 0, radiusPx, 0, Math.PI * 2);
        ctx.lineWidth = 2;
        ctx.strokeStyle = moonStroke;
        ctx.stroke();
        ctx.restore();
    }

    function chunkStars(stars, size) {
        const chunks = [];
        for (let index = 0; index < stars.length; index += size) {
            chunks.push(stars.slice(index, index + size));
        }
        return chunks;
    }

    function defineChunk(chunk) {
        STAR_BODIES.forEach((body, index) => {
            const star = chunk[index];
            if (star) {
                Astronomy.DefineStar(body, Number(star.ra), Number(star.dec), Number(star.distLy || 1000));
                return;
            }
            Astronomy.DefineStar(body, 0, 0, 1000);
        });
    }

    function getStarsForDetailMap(time, event) {
        const mapStars = DETAIL_MAP_STARS.filter((star) => Number(star.mag) <= DETAIL_MAP_CATALOG_LIMIT);
        const chunks = chunkStars(mapStars, STAR_BODIES.length);
        const stars = [];

        for (const chunk of chunks) {
            defineChunk(chunk);
            chunk.forEach((star, index) => {
                const starEq = Astronomy.Equator(STAR_BODIES[index], time, OBSERVER, true, true);
                const starHor = Astronomy.Horizon(time, OBSERVER, starEq.ra, starEq.dec, 'normal');
                if (Number(starHor.altitude || 0) <= 0) {
                    return;
                }

                stars.push({
                    star,
                    eq: starEq,
                    hor: starHor,
                    isTarget: Number(star.hip) === Number(event.star && event.star.hip)
                });
            });
        }

        return stars;
    }

    function clipSegmentToField(x1, y1, x2, y2, halfWidth, halfHeight) {
        const INSIDE = 0;
        const LEFT = 1;
        const RIGHT = 2;
        const BOTTOM = 4;
        const TOP = 8;

        function computeCode(x, y) {
            let code = INSIDE;
            if (x < -halfWidth) code |= LEFT;
            else if (x > halfWidth) code |= RIGHT;
            if (y < -halfHeight) code |= BOTTOM;
            else if (y > halfHeight) code |= TOP;
            return code;
        }

        let ax = x1;
        let ay = y1;
        let bx = x2;
        let by = y2;
        let codeA = computeCode(ax, ay);
        let codeB = computeCode(bx, by);

        while (true) {
            if ((codeA | codeB) === 0) {
                return { x1: ax, y1: ay, x2: bx, y2: by };
            }
            if ((codeA & codeB) !== 0) {
                return null;
            }

            const outCode = codeA !== 0 ? codeA : codeB;
            let x = 0;
            let y = 0;

            if (outCode & TOP) {
                x = ax + (bx - ax) * (halfHeight - ay) / (by - ay);
                y = halfHeight;
            } else if (outCode & BOTTOM) {
                x = ax + (bx - ax) * (-halfHeight - ay) / (by - ay);
                y = -halfHeight;
            } else if (outCode & RIGHT) {
                y = ay + (by - ay) * (halfWidth - ax) / (bx - ax);
                x = halfWidth;
            } else if (outCode & LEFT) {
                y = ay + (by - ay) * (-halfWidth - ax) / (bx - ax);
                x = -halfWidth;
            }

            if (outCode === codeA) {
                ax = x;
                ay = y;
                codeA = computeCode(ax, ay);
            } else {
                bx = x;
                by = y;
                codeB = computeCode(bx, by);
            }
        }
    }

    function getConstellationSegmentsForDetailMap(time, moonEq, fieldHalfDeg) {
        const segments = [];

        for (const line of CONSTELLATION_LINES) {
            if (!Array.isArray(line) || line.length < 2) {
                continue;
            }

            let prevPoint = null;
            for (const point of line) {
                if (!point || !Number.isFinite(point.ra) || !Number.isFinite(point.dec)) {
                    prevPoint = null;
                    continue;
                }

                const tempBody = 'Star1';
                Astronomy.DefineStar(tempBody, Number(point.ra), Number(point.dec), 1000);
                const eq = Astronomy.Equator(tempBody, time, OBSERVER, true, true);
                const hor = Astronomy.Horizon(time, OBSERVER, eq.ra, eq.dec, 'normal');
                const offset = angularOffsetDeg(eq.ra, eq.dec, moonEq.ra, moonEq.dec);

                const currentPoint = {
                    xDeg: offset.xDeg,
                    yDeg: offset.yDeg,
                    visible: Number(hor.altitude || 0) > 0,
                };

                if (prevPoint && (prevPoint.visible || currentPoint.visible)) {
                    const clipped = clipSegmentToField(
                        prevPoint.xDeg,
                        prevPoint.yDeg,
                        currentPoint.xDeg,
                        currentPoint.yDeg,
                        fieldHalfDeg,
                        fieldHalfDeg
                    );

                    if (clipped) {
                        segments.push({
                            x1Deg: clipped.x1,
                            y1Deg: clipped.y1,
                            x2Deg: clipped.x2,
                            y2Deg: clipped.y2,
                        });
                    }
                }

                prevPoint = currentPoint;
            }
        }

        return segments;
    }

    function renderOccultationMap(eventIndex) {
        const event = STATE.results[eventIndex];
        if (!event || !detailCanvasEl || !Astronomy) {
            return;
        }

        STATE.selectedEventIndex = eventIndex;
        detailCardEl.hidden = false;

        const ctx = detailCanvasEl.getContext('2d');
        const width = detailCanvasEl.width;
        const height = detailCanvasEl.height;
        const padding = 28;
        const plotSize = Math.min(width, height) - padding * 2;
        const fieldHalfDeg = STATE.mapSizeDeg / 2;
        const scale = plotSize / (fieldHalfDeg * 2);
        const centerX = width / 2;
        const centerY = height / 2;
        const timeMs = event.ingressMs || event.maxMs;
        const time = new Date(timeMs);
        const moonEq = Astronomy.Equator('Moon', time, OBSERVER, true, true);
        const moonRadiusDeg = Math.asin(Math.max(-1, Math.min(1, 1737.4 / (Number(moonEq.dist || 1) * Astronomy.KM_PER_AU)))) * Astronomy.RAD2DEG;
        const moonTerminatorInfo = getMoonTerminatorInfo(time, moonEq);
        const mapStars = getStarsForDetailMap(time, event);
        const constellationSegments = getConstellationSegmentsForDetailMap(time, moonEq, fieldHalfDeg);
        const nearbyStars = [];
        const labelItems = [];

        ctx.clearRect(0, 0, width, height);
        ctx.fillStyle = STATE.invertMap ? '#f7f8fb' : '#000000';
        ctx.fillRect(0, 0, width, height);

        ctx.strokeStyle = STATE.invertMap ? 'rgba(120, 145, 185, 0.36)' : 'rgba(95, 135, 185, 0.34)';
        ctx.lineWidth = 1;
        constellationSegments.forEach((segment) => {
            ctx.beginPath();
            ctx.moveTo(centerX - segment.x1Deg * scale, centerY - segment.y1Deg * scale);
            ctx.lineTo(centerX - segment.x2Deg * scale, centerY - segment.y2Deg * scale);
            ctx.stroke();
        });

        mapStars.forEach((item) => {
            const offset = angularOffsetDeg(item.eq.ra, item.eq.dec, moonEq.ra, moonEq.dec);
            if (Math.abs(offset.xDeg) <= fieldHalfDeg * 1.12 && Math.abs(offset.yDeg) <= fieldHalfDeg * 1.12) {
                nearbyStars.push({
                    star: item.star,
                    offset,
                    isTarget: item.isTarget
                });
            }
        });

        nearbyStars.forEach((starItem) => {
            const x = centerX - starItem.offset.xDeg * scale;
            const y = centerY - starItem.offset.yDeg * scale;
            drawStarSymbol(ctx, x, y, starItem.star.mag, starItem.isTarget);

            if (starItem.isTarget || Number(starItem.star.mag) <= DETAIL_MAP_LABEL_LIMIT) {
                const label = starItem.star.label || (starItem.star.hip ? `HIP ${starItem.star.hip}` : '');
                labelItems.push({
                    x,
                    y,
                    label,
                    isTarget: starItem.isTarget,
                    mag: Number(starItem.star.mag)
                });
            }
        });

        drawMoonWithTerminator(ctx, centerX, centerY, Math.max(6, moonRadiusDeg * scale), moonTerminatorInfo);

        const placedLabelBoxes = [];
        labelItems
            .sort((left, right) => {
                if (left.isTarget !== right.isTarget) {
                    return left.isTarget ? -1 : 1;
                }
                return left.mag - right.mag;
            })
            .forEach((item) => {
                if (!item.label) {
                    return;
                }

                const metrics = getStarLabelMetrics(ctx, item.label, item.isTarget);
                const placements = getLabelPlacementOptions(item.x, item.y, metrics);
                let chosenPlacement = null;

                for (const placement of placements) {
                    const candidateBox = {
                        left: placement.boxX,
                        top: placement.boxY - placement.boxH / 2,
                        right: placement.boxX + placement.boxW,
                        bottom: placement.boxY + placement.boxH / 2,
                    };

                    const collides = placedLabelBoxes.some((placed) => labelBoxesOverlap(candidateBox, placed));
                    if (!collides) {
                        chosenPlacement = placement;
                        break;
                    }
                }

                if (!chosenPlacement) {
                    chosenPlacement = placements[0];
                }

                const labelBox = drawStarLabel(ctx, item.x, item.y, item.label, item.isTarget, chosenPlacement);
                if (labelBox) {
                    placedLabelBoxes.push(labelBox);
                }
            });

        detailTitleEl.textContent = `${event.star.label || 'Stern'} - Beginn der Bedeckung`;
        detailMetaEl.textContent = `${TIME_FMT.format(time)} Uhr, Feld ${STATE.mapSizeDeg} x ${STATE.mapSizeDeg} Grad, Mond im Zentrum`;
        detailInfoEl.innerHTML = `
            <div class="occult-detail-row"><span>Zeit</span><strong>${TIME_FMT.format(time)} Uhr</strong></div>
            <div class="occult-detail-row"><span>Stern</span><strong>${escapeHtml(event.star.label || '')}</strong></div>
            <div class="occult-detail-row"><span>Magnitude</span><strong>${Number(event.star.mag || 99).toFixed(2)}</strong></div>
            <div class="occult-detail-row"><span>Phase</span><strong>${(moonTerminatorInfo.phaseFraction * 100).toFixed(1)} %</strong></div>
            <div class="occult-detail-row"><span>Sterne im Feld</span><strong>${nearbyStars.length}</strong></div>
            <div class="occult-detail-row"><span>Mondradius</span><strong>${(moonRadiusDeg * 60).toFixed(2)}'</strong></div>
            <div class="occult-detail-row"><span>Maximum</span><strong>${formatTimeBlock(event.maximum)}</strong></div>
        `;

        document.querySelectorAll('#occultResults tr[data-event-index]').forEach((row) => {
            row.classList.toggle('occult-row-active', Number(row.dataset.eventIndex) === eventIndex);
        });
        detailCanvasEl.classList.toggle('occult-canvas-inverted', STATE.invertMap);
    }

    async function fetchOccultationsForDate(dateString) {
        const formData = new FormData(form);
        formData.set('ajax', '1');
        formData.set('date', dateString);
        formData.set('mag', magSelect.value);
        const response = await fetch(window.location.href, {
            method: 'POST',
            body: formData,
            headers: { 'X-Requested-With': 'fetch' }
        });
        return response.json();
    }

    async function runRange(mode) {
        const baseDate = datePicker.value || '<?= h($selectedDate) ?>';
        const dayStrings = [];
        if (mode === 'week') {
            for (let i = 0; i < 7; i += 1) dayStrings.push(shiftDateString(baseDate, i));
        } else if (mode === 'month') {
            const date = new Date(`${baseDate}T12:00:00Z`);
            const year = date.getUTCFullYear();
            const month = date.getUTCMonth();
            const daysInMonth = new Date(Date.UTC(year, month + 1, 0)).getUTCDate();
            for (let d = 1; d <= daysInMonth; d += 1) {
                dayStrings.push(new Date(Date.UTC(year, month, d, 12, 0, 0)).toISOString().slice(0, 10));
            }
        } else {
            dayStrings.push(baseDate);
        }

        if (isSubmitting) {
            return;
        }

        isSubmitting = true;
        status.hidden = false;
        status.classList.remove('occult-status-hidden');
        overlay.hidden = false;
        overlay.classList.add('is-visible');
        const submitButton = form.querySelector('button[type="submit"]');
        if (submitButton) {
            submitButton.disabled = true;
            submitButton.textContent = 'Berechnet...';
        }
        if (weekBtn) weekBtn.disabled = true;
        if (monthBtn) monthBtn.disabled = true;

        const allResults = [];
        let totalStarCount = 0;
        try {
            for (let i = 0; i < dayStrings.length; i += 1) {
                setRangeProgress(i, dayStrings.length);
                const payload = await fetchOccultationsForDate(dayStrings[i]);
                if (!payload || !payload.ok) {
                    stopEstimatedProgress(false);
                    renderError(payload && payload.error ? payload.error : 'Unbekannter Fehler', payload && payload.debug ? payload.debug : '');
                    return;
                }
                totalStarCount = payload.star_count || totalStarCount;
                (payload.results || []).forEach((row) => {
                    allResults.push({ ...row, _dateString: dayStrings[i] });
                });
            }
            setRangeProgress(dayStrings.length, dayStrings.length);
            renderSuccess({
                star_count: totalStarCount,
                results: allResults,
                selected_date: baseDate,
                selected_mag: Number(magSelect.value || 3.0),
                range_start: dayStrings[0] || baseDate,
                range_end: dayStrings[dayStrings.length - 1] || baseDate
            });
        } catch (error) {
            renderError('Die Berechnung konnte nicht abgeschlossen werden.', error && error.message ? error.message : '');
        } finally {
            isSubmitting = false;
            window.setTimeout(function () {
                status.hidden = true;
                status.classList.add('occult-status-hidden');
                overlay.hidden = true;
                overlay.classList.remove('is-visible');
                setEstimatedProgress(0);
                if (submitButton) {
                    submitButton.disabled = false;
                    submitButton.textContent = 'Berechnen';
                }
                if (weekBtn) weekBtn.disabled = false;
                if (monthBtn) monthBtn.disabled = false;
            }, 220);
        }
    }

    form.addEventListener('submit', function (event) {
        if (isSubmitting) {
            event.preventDefault();
            return;
        }

        event.preventDefault();
        isSubmitting = true;
        status.hidden = false;
        status.classList.remove('occult-status-hidden');
        overlay.hidden = false;
        overlay.classList.add('is-visible');
        startEstimatedProgress();

        const submitButton = form.querySelector('button[type="submit"]');
        if (submitButton) {
            submitButton.disabled = true;
            submitButton.textContent = 'Berechnet...';
        }

        fetchOccultationsForDate(datePicker.value || '<?= h($selectedDate) ?>')
            .then(function (payload) {
                if (!payload || !payload.ok) {
                    stopEstimatedProgress(false);
                    renderError(payload && payload.error ? payload.error : 'Unbekannter Fehler', payload && payload.debug ? payload.debug : '');
                    return;
                }

                stopEstimatedProgress(true);
                renderSuccess(payload);
            })
            .catch(function (error) {
                stopEstimatedProgress(false);
                renderError('Die Berechnung konnte nicht abgeschlossen werden.', error && error.message ? error.message : '');
            })
            .finally(function () {
                isSubmitting = false;
                window.setTimeout(function () {
                    status.hidden = true;
                    status.classList.add('occult-status-hidden');
                    overlay.hidden = true;
                    overlay.classList.remove('is-visible');
                    setEstimatedProgress(0);

                    if (submitButton) {
                        submitButton.disabled = false;
                        submitButton.textContent = 'Berechnen';
                    }
                }, 220);
            });
    });

    if (prevDayBtn && datePicker) {
        prevDayBtn.addEventListener('click', function () {
            datePicker.value = shiftDateString(datePicker.value || '<?= h($selectedDate) ?>', -1);
        });
    }

    if (nextDayBtn && datePicker) {
        nextDayBtn.addEventListener('click', function () {
            datePicker.value = shiftDateString(datePicker.value || '<?= h($selectedDate) ?>', 1);
        });
    }

    if (todayBtn && datePicker) {
        todayBtn.addEventListener('click', function () {
            datePicker.value = getTodayDateString();
        });
    }

    if (weekBtn) {
        weekBtn.addEventListener('click', function () {
            runRange('week');
        });
    }

    if (monthBtn) {
        monthBtn.addEventListener('click', function () {
            runRange('month');
        });
    }

    if (mapSizeSelectEl) {
        mapSizeSelectEl.addEventListener('change', function () {
            STATE.mapSizeDeg = Number(mapSizeSelectEl.value || 5);
            if (STATE.selectedEventIndex !== null) {
                renderOccultationMap(STATE.selectedEventIndex);
            }
        });
    }

    if (invertBtn) {
        invertBtn.addEventListener('click', function () {
            STATE.invertMap = !STATE.invertMap;
            invertBtn.classList.toggle('is-active', STATE.invertMap);
            if (STATE.selectedEventIndex !== null) {
                renderOccultationMap(STATE.selectedEventIndex);
            } else if (detailCanvasEl) {
                detailCanvasEl.classList.toggle('occult-canvas-inverted', STATE.invertMap);
            }
        });
    }
})();
</script>

<?php require __DIR__ . '/footer.php'; ?>