<?php
declare(strict_types=1);

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

$loggedIn = isset($_SESSION['user_id']);
$pageTitle = 'Kometen - AstroTools';
$headerIntroPre = 'Himmel & Planeten';
$headerIntroTitle = 'Kometen';
$headerIntroSub = 'Interessante Kometen aus der MPC-Datenbank mit Fokus auf bevorstehende und aktuelle Periheldurchgaenge.';

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

function formatDecimalGerman(?float $value, int $decimals = 3): string
{
    if ($value === null || !is_finite($value)) {
        return '-';
    }

    return number_format($value, $decimals, ',', '.');
}

function buildPerihelionDate(array $row): ?DateTimeImmutable
{
    $year = isset($row['year_of_perihelion']) ? (int) $row['year_of_perihelion'] : 0;
    $month = isset($row['month_of_perihelion']) ? (int) $row['month_of_perihelion'] : 0;
    $dayValue = isset($row['day_of_perihelion']) ? (float) $row['day_of_perihelion'] : 0.0;

    if ($year === 0 || $month < 1 || $month > 12 || $dayValue <= 0) {
        return null;
    }

    $day = (int) floor($dayValue);
    if ($day < 1 || $day > 31) {
        return null;
    }

    $fractionalDay = $dayValue - $day;
    $seconds = (int) round($fractionalDay * 86400);

    try {
        $date = new DateTimeImmutable(sprintf('%04d-%02d-%02d 00:00:00', $year, $month, $day), new DateTimeZone('UTC'));
    } catch (Throwable $e) {
        return null;
    }

    return $date->modify(sprintf('+%d seconds', $seconds));
}

function classifyOrbitType(string $orbitType): string
{
    return match (strtoupper(trim($orbitType))) {
        'P' => 'Periodisch',
        'C' => 'Nicht periodisch',
        'I' => 'Interstellar',
        'D' => 'Verschollen / zerfallen',
        'A' => 'Asteroidal',
        default => trim($orbitType) !== '' ? trim($orbitType) : '-',
    };
}

function estimatePerihelMagnitude(?float $absoluteMagnitudeH, ?float $perihelionDistanceAu): ?float
{
    if ($absoluteMagnitudeH === null || !is_finite($absoluteMagnitudeH) || $perihelionDistanceAu === null || !is_finite($perihelionDistanceAu) || $perihelionDistanceAu <= 0.0) {
        return null;
    }

    $heliocentricDistance = max(0.05, $perihelionDistanceAu);
    $geocentricDistance = max(0.2, abs(1.0 - $perihelionDistanceAu));

    return $absoluteMagnitudeH
        + (5.0 * log10($geocentricDistance))
        + (10.0 * log10($heliocentricDistance));
}

$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,
    ]
);

$userId = isset($_SESSION['user_id']) ? (int) $_SESSION['user_id'] : 0;
$today = new DateTimeImmutable('today', new DateTimeZone('UTC'));
$windowStart = $today->modify('-180 days');
$windowEnd = $today->modify('+365 days');
$queryYearMin = (int) $windowStart->format('Y') - 1;
$queryYearMax = (int) $windowEnd->format('Y') + 1;

$stmtComets = $pdo->prepare("
    SELECT
        c.*,
        CASE WHEN auc.`comet_id` IS NULL THEN 0 ELSE 1 END AS `is_tracked`,
        CASE WHEN auc.`is_favorite` = 1 THEN 1 ELSE 0 END AS `is_favorite`
    FROM `comets_mpc` c
    LEFT JOIN `app_user_comets` auc
        ON auc.`comet_id` = c.`id`
       AND auc.`user_id` = :user_id
    WHERE c.`year_of_perihelion` BETWEEN :year_min AND :year_max
       OR auc.`comet_id` IS NOT NULL
    ORDER BY c.`year_of_perihelion` ASC, c.`month_of_perihelion` ASC, c.`day_of_perihelion` ASC, c.`designation_and_name` ASC
");
$stmtComets->execute([
    ':user_id' => $userId,
    ':year_min' => $queryYearMin,
    ':year_max' => $queryYearMax,
]);

$allComets = [];
$trackedComets = [];
$interestingComets = [];

foreach ($stmtComets as $row) {
    $perihelionDate = buildPerihelionDate($row);
    $daysFromToday = $perihelionDate ? (int) floor(($perihelionDate->getTimestamp() - $today->getTimestamp()) / 86400) : null;

    $row['perihelion_date_object'] = $perihelionDate;
    $row['perihelion_date_display'] = $perihelionDate ? $perihelionDate->setTimezone(new DateTimeZone('Europe/Berlin'))->format('d.m.Y H:i') . ' UTC' : '-';
    $row['days_from_today'] = $daysFromToday;
    $row['orbit_type_label'] = classifyOrbitType((string) ($row['orbit_type'] ?? ''));
    $row['absolute_magnitude_display'] = isset($row['absolute_magnitude_h']) && $row['absolute_magnitude_h'] !== null
        ? formatDecimalGerman((float) $row['absolute_magnitude_h'], 1)
        : '-';
    $row['slope_parameter_display'] = isset($row['slope_parameter_g']) && $row['slope_parameter_g'] !== null
        ? formatDecimalGerman((float) $row['slope_parameter_g'], 1)
        : '-';
    $row['perihelion_dist_display'] = formatDecimalGerman(isset($row['perihelion_dist_au']) ? (float) $row['perihelion_dist_au'] : null, 3);
    $row['eccentricity_display'] = formatDecimalGerman(isset($row['eccentricity']) ? (float) $row['eccentricity'] : null, 4);
    $row['inclination_display'] = formatDecimalGerman(isset($row['inclination_deg']) ? (float) $row['inclination_deg'] : null, 2);
    $estimatedPerihelMagnitude = estimatePerihelMagnitude(
        isset($row['absolute_magnitude_h']) && $row['absolute_magnitude_h'] !== null ? (float) $row['absolute_magnitude_h'] : null,
        isset($row['perihelion_dist_au']) && $row['perihelion_dist_au'] !== null ? (float) $row['perihelion_dist_au'] : null
    );
    $row['estimated_perihel_magnitude'] = $estimatedPerihelMagnitude;
    $row['estimated_perihel_magnitude_display'] = $estimatedPerihelMagnitude !== null
        ? formatDecimalGerman($estimatedPerihelMagnitude, 1)
        : '-';

    $allComets[] = $row;

    if ((int) ($row['is_tracked'] ?? 0) === 1) {
        $trackedComets[] = $row;
    }

    if ($perihelionDate !== null && $perihelionDate >= $windowStart && $perihelionDate <= $windowEnd) {
        $interestingComets[] = $row;
    }
}

usort($trackedComets, static function (array $left, array $right): int {
    $favoriteCompare = ((int) $right['is_favorite']) <=> ((int) $left['is_favorite']);
    if ($favoriteCompare !== 0) {
        return $favoriteCompare;
    }

    return ((int) ($left['days_from_today'] ?? PHP_INT_MAX)) <=> ((int) ($right['days_from_today'] ?? PHP_INT_MAX));
});

usort($interestingComets, static function (array $left, array $right): int {
    $leftDistance = abs((int) ($left['days_from_today'] ?? PHP_INT_MAX));
    $rightDistance = abs((int) ($right['days_from_today'] ?? PHP_INT_MAX));
    if ($leftDistance !== $rightDistance) {
        return $leftDistance <=> $rightDistance;
    }

    return strcmp((string) $left['designation_and_name'], (string) $right['designation_and_name']);
});

$interestingComets = array_slice($interestingComets, 0, 24);
$orbitTypeCounts = [];
foreach ($allComets as $comet) {
    $orbitKey = (string) ($comet['orbit_type'] ?? '?');
    $orbitTypeCounts[$orbitKey] = ($orbitTypeCounts[$orbitKey] ?? 0) + 1;
}
arsort($orbitTypeCounts);
?>
<?php require __DIR__ . '/header.php'; ?>

<style>
.comets-layout {
    display: grid;
    gap: 1.25rem;
}

.comets-intro {
    color: #d9e7ff;
    line-height: 1.65;
    margin: 0;
}

.comets-summary {
    display: grid;
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: 0.9rem;
}

.comets-stat {
    padding: 1rem 1.1rem;
    border-radius: 1rem;
    border: 1px solid rgba(130, 170, 255, 0.16);
    background:
        radial-gradient(circle at top left, rgba(82, 153, 255, 0.12), transparent 36%),
        linear-gradient(180deg, rgba(13, 19, 33, 0.96), rgba(8, 11, 20, 0.98));
}

.comets-stat-label {
    color: #9db2d4;
    font-size: 0.82rem;
    text-transform: uppercase;
    letter-spacing: 0.08em;
}

.comets-stat-value {
    margin-top: 0.45rem;
    color: #ffffff;
    font-size: 1.8rem;
    font-weight: 700;
}

.comets-stat-help {
    margin-top: 0.35rem;
    color: #c7d6f4;
    font-size: 0.92rem;
}

.comets-card {
    padding: 1.2rem;
}

.comets-card h2 {
    margin-bottom: 0.45rem;
}

.comets-card .hint {
    margin-top: 0;
}

.comets-chip-row {
    display: flex;
    flex-wrap: wrap;
    gap: 0.7rem;
    margin-top: 1rem;
}

.comets-chip {
    padding: 0.45rem 0.7rem;
    border-radius: 999px;
    border: 1px solid rgba(130, 170, 255, 0.18);
    background: rgba(255, 255, 255, 0.04);
    color: #dce8ff;
    font-size: 0.92rem;
}

.comets-table-wrap {
    overflow-x: auto;
}

.comets-table {
    width: 100%;
    border-collapse: collapse;
    margin-top: 1rem;
}

.comets-table th,
.comets-table td {
    padding: 0.78rem 0.8rem;
    border-bottom: 1px solid rgba(130, 170, 255, 0.12);
    text-align: left;
    vertical-align: top;
}

.comets-table th {
    color: #a9bee0;
    font-size: 0.84rem;
    text-transform: uppercase;
    letter-spacing: 0.08em;
}

.comets-table td {
    color: #eef4ff;
}

.comets-name {
    font-weight: 600;
}

.comets-meta {
    display: flex;
    flex-wrap: wrap;
    gap: 0.45rem;
    margin-top: 0.35rem;
}

.comets-badge {
    display: inline-flex;
    align-items: center;
    gap: 0.35rem;
    padding: 0.22rem 0.5rem;
    border-radius: 999px;
    font-size: 0.8rem;
    color: #eef4ff;
    background: rgba(255, 255, 255, 0.08);
    border: 1px solid rgba(255, 255, 255, 0.12);
}

.comets-badge.is-favorite {
    background: rgba(255, 208, 102, 0.12);
    border-color: rgba(255, 208, 102, 0.28);
    color: #ffd98b;
}

.comets-badge.is-tracked {
    background: rgba(130, 170, 255, 0.12);
    border-color: rgba(130, 170, 255, 0.26);
    color: #bfd6ff;
}

.comets-days {
    font-weight: 600;
}

.comets-days.is-past {
    color: #ffb2a8;
}

.comets-days.is-upcoming {
    color: #b8f0c8;
}

@media (max-width: 960px) {
    .comets-summary {
        grid-template-columns: repeat(2, minmax(0, 1fr));
    }
}

@media (max-width: 640px) {
    .comets-summary {
        grid-template-columns: 1fr;
    }
}
</style>

<div class="comets-layout">
    <section class="card comets-card">
        <p class="comets-intro">
            Diese erste Version liest die vorhandenen Kometen direkt aus <code>comets_mpc</code> und hebt Objekte hervor,
            deren Perihel zwischen <strong><?= h($windowStart->format('d.m.Y')) ?></strong> und
            <strong><?= h($windowEnd->format('d.m.Y')) ?></strong> liegt.
            Nutzer-Favoriten aus <code>app_user_comets</code> werden zusaetzlich separat gezeigt.
        </p>
        <p class="hint">
            Die Spalte <strong>m grob</strong> ist eine sehr einfache Helligkeitsschaetzung nahe dem Perihel
            auf Basis von MPC-<code>H</code> und <code>q</code>. Sie ist nur als Orientierung gedacht.
        </p>

        <div class="comets-chip-row">
            <?php foreach (array_slice($orbitTypeCounts, 0, 5, true) as $orbitType => $count): ?>
                <span class="comets-chip"><?= h(classifyOrbitType((string) $orbitType)) ?>: <?= (int) $count ?></span>
            <?php endforeach; ?>
        </div>
    </section>

    <section class="comets-summary">
        <div class="comets-stat">
            <div class="comets-stat-label">Kometen im Blickfenster</div>
            <div class="comets-stat-value"><?= count($interestingComets) ?></div>
            <div class="comets-stat-help">Perihel im aktuellen Zeitfenster</div>
        </div>
        <div class="comets-stat">
            <div class="comets-stat-label">Meine Kometen</div>
            <div class="comets-stat-value"><?= count($trackedComets) ?></div>
            <div class="comets-stat-help">Aus den Favoriten uebernommen</div>
        </div>
        <div class="comets-stat">
            <div class="comets-stat-label">Gesamt in Datenbank</div>
            <div class="comets-stat-value"><?= count($allComets) ?></div>
            <div class="comets-stat-help">Geladene Datensaetze im relevanten Jahresbereich</div>
        </div>
        <div class="comets-stat">
            <div class="comets-stat-label">Zeitraum</div>
            <div class="comets-stat-value"><?= h($today->format('Y')) ?></div>
            <div class="comets-stat-help"><?= h($windowStart->format('d.m.Y')) ?> bis <?= h($windowEnd->format('d.m.Y')) ?></div>
        </div>
    </section>

    <section class="card comets-card">
        <h2>Meine Kometen</h2>
        <?php if (empty($trackedComets)): ?>
            <p class="hint">Du hast aktuell noch keine Kometen in deinen Favoriten. In <a href="my_favorites.php">Favoriten</a> kannst du welche markieren.</p>
        <?php else: ?>
            <div class="comets-table-wrap">
                <table class="comets-table">
                    <thead>
                        <tr>
                            <th>Komet</th>
                            <th>Typ</th>
                            <th>Perihel</th>
                            <th>Abstand</th>
                            <th title="Sehr grobe Helligkeitsschaetzung nahe dem Perihel.">m grob</th>
                        </tr>
                    </thead>
                    <tbody>
                        <?php foreach ($trackedComets as $comet): ?>
                            <?php
                            $daysClass = ((int) ($comet['days_from_today'] ?? 0)) < 0 ? 'is-past' : 'is-upcoming';
                            $daysLabel = $comet['days_from_today'] === null
                                ? '-'
                                : ((int) $comet['days_from_today'] === 0
                                    ? 'Heute'
                                    : (((int) $comet['days_from_today'] > 0 ? '+' : '') . (int) $comet['days_from_today'] . ' Tage'));
                            ?>
                            <tr>
                                <td>
                                    <div class="comets-name"><?= h((string) $comet['designation_and_name']) ?></div>
                                    <div class="comets-meta">
                                        <?php if ((int) $comet['is_favorite'] === 1): ?>
                                            <span class="comets-badge is-favorite">Favorit</span>
                                        <?php endif; ?>
                                        <span class="comets-badge is-tracked">Beobachtet</span>
                                        <?php if (!empty($comet['reference_text'])): ?>
                                            <span class="comets-badge"><?= h((string) $comet['reference_text']) ?></span>
                                        <?php endif; ?>
                                    </div>
                                </td>
                                <td><?= h((string) $comet['orbit_type_label']) ?></td>
                                <td><?= h((string) $comet['perihelion_date_display']) ?></td>
                                <td><span class="comets-days <?= $daysClass ?>"><?= h($daysLabel) ?></span></td>
                                <td title="Sehr grobe Helligkeitsschaetzung nahe dem Perihel."><?= h((string) $comet['estimated_perihel_magnitude_display']) ?></td>
                            </tr>
                        <?php endforeach; ?>
                    </tbody>
                </table>
            </div>
        <?php endif; ?>
    </section>

    <section class="card comets-card">
        <h2>Interessante Kometen</h2>
        <p class="hint">Sortiert nach Naehe zum heutigen Datum bezogen auf den Periheldurchgang.</p>
        <?php if (empty($interestingComets)): ?>
            <p class="hint">Im aktuellen Zeitfenster wurden keine Kometen gefunden.</p>
        <?php else: ?>
            <div class="comets-table-wrap">
                <table class="comets-table">
                    <thead>
                        <tr>
                            <th>Komet</th>
                            <th>Typ</th>
                            <th>Perihel</th>
                            <th>Abstand</th>
                            <th title="Sehr grobe Helligkeitsschaetzung nahe dem Perihel.">m grob</th>
                            <th>H</th>
                            <th>G</th>
                        </tr>
                    </thead>
                    <tbody>
                        <?php foreach ($interestingComets as $comet): ?>
                            <?php
                            $daysClass = ((int) ($comet['days_from_today'] ?? 0)) < 0 ? 'is-past' : 'is-upcoming';
                            $daysLabel = $comet['days_from_today'] === null
                                ? '-'
                                : ((int) $comet['days_from_today'] === 0
                                    ? 'Heute'
                                    : (((int) $comet['days_from_today'] > 0 ? '+' : '') . (int) $comet['days_from_today'] . ' Tage'));
                            ?>
                            <tr>
                                <td>
                                    <div class="comets-name"><?= h((string) $comet['designation_and_name']) ?></div>
                                    <div class="comets-meta">
                                        <?php if ((int) $comet['is_favorite'] === 1): ?>
                                            <span class="comets-badge is-favorite">Favorit</span>
                                        <?php elseif ((int) $comet['is_tracked'] === 1): ?>
                                            <span class="comets-badge is-tracked">Beobachtet</span>
                                        <?php endif; ?>
                                        <?php if (!empty($comet['reference_text'])): ?>
                                            <span class="comets-badge"><?= h((string) $comet['reference_text']) ?></span>
                                        <?php endif; ?>
                                    </div>
                                </td>
                                <td><?= h((string) $comet['orbit_type_label']) ?></td>
                                <td><?= h((string) $comet['perihelion_date_display']) ?></td>
                                <td><span class="comets-days <?= $daysClass ?>"><?= h($daysLabel) ?></span></td>
                                <td title="Sehr grobe Helligkeitsschaetzung nahe dem Perihel."><?= h((string) $comet['estimated_perihel_magnitude_display']) ?></td>
                                <td><?= h((string) $comet['absolute_magnitude_display']) ?></td>
                                <td><?= h((string) $comet['slope_parameter_display']) ?></td>
                            </tr>
                        <?php endforeach; ?>
                    </tbody>
                </table>
            </div>
        <?php endif; ?>
    </section>
</div>

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