<?php
declare(strict_types=1);

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

if (!isset($_SESSION['user_id'])) {
    header('Location: login.php');
    exit;
}

$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 = (int) $_SESSION['user_id'];
$errors = [];
$successMessage = '';
$satelliteSearchResults = [];
$minorplanetSearchResults = [];
$satelliteSearchQuery = trim($_GET['sat_q'] ?? '');
$minorplanetSearchQuery = trim($_GET['mp_q'] ?? '');
$pageTitle = 'Favoriten - AstroTools';
$headerIntroPre = 'Merkliste';
$headerIntroTitle = 'Favoriten';
$headerIntroSub = 'Satelliten und Kleinplaneten zentral verwalten.';

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

function setExclusiveFavorite(PDO $pdo, string $tableName, string $idColumn, int $userId, int $entityId): bool
{
    $pdo->beginTransaction();

    try {
        $stmtCurrent = $pdo->prepare("
            SELECT `is_favorite`
            FROM `{$tableName}`
            WHERE `user_id` = :user_id
              AND `{$idColumn}` = :entity_id
            LIMIT 1
        ");
        $stmtCurrent->execute([
            ':user_id' => $userId,
            ':entity_id' => $entityId,
        ]);
        $current = $stmtCurrent->fetchColumn();

        if ($current === false) {
            $pdo->rollBack();
            return false;
        }

        $newValue = (int) $current === 1 ? 0 : 1;

        if ($newValue === 1) {
            $stmtReset = $pdo->prepare("
                UPDATE `{$tableName}`
                SET `is_favorite` = 0
                WHERE `user_id` = :user_id
            ");
            $stmtReset->execute([
                ':user_id' => $userId,
            ]);
        }

        $stmtSet = $pdo->prepare("
            UPDATE `{$tableName}`
            SET `is_favorite` = :is_favorite
            WHERE `user_id` = :user_id
              AND `{$idColumn}` = :entity_id
        ");
        $stmtSet->execute([
            ':is_favorite' => $newValue,
            ':user_id' => $userId,
            ':entity_id' => $entityId,
        ]);

        $pdo->commit();
        return true;
    } catch (Throwable $e) {
        if ($pdo->inTransaction()) {
            $pdo->rollBack();
        }
        throw $e;
    }
}

if ($_SERVER['REQUEST_METHOD'] === 'POST') {
    $action = $_POST['action'] ?? '';

    if ($action === 'add_satellite') {
        $satelliteId = (int) ($_POST['satellite_id'] ?? 0);

        if ($satelliteId <= 0) {
            $errors[] = 'Ungueltiger Satellit.';
        }

        if (empty($errors)) {
            $stmtCheck = $pdo->prepare("
                SELECT `id`
                FROM `sat_satellites`
                WHERE `id` = :id
                LIMIT 1
            ");
            $stmtCheck->execute([
                ':id' => $satelliteId,
            ]);

            if (!$stmtCheck->fetch()) {
                $errors[] = 'Der Satellit wurde nicht gefunden.';
            }
        }

        if (empty($errors)) {
            $stmtInsert = $pdo->prepare("
                INSERT INTO `app_user_satellites` (
                    `user_id`,
                    `satellite_id`,
                    `is_favorite`,
                    `created_at`
                ) VALUES (
                    :user_id,
                    :satellite_id,
                    0,
                    NOW()
                )
                ON DUPLICATE KEY UPDATE
                    `satellite_id` = VALUES(`satellite_id`)
            ");
            $stmtInsert->execute([
                ':user_id' => $userId,
                ':satellite_id' => $satelliteId,
            ]);

            $successMessage = 'Der Satellit wurde hinzugefuegt.';
        }
    }

    if ($action === 'remove_satellite') {
        $satelliteId = (int) ($_POST['satellite_id'] ?? 0);

        if ($satelliteId <= 0) {
            $errors[] = 'Ungueltiger Satellit.';
        }

        if (empty($errors)) {
            $stmtDelete = $pdo->prepare("
                DELETE FROM `app_user_satellites`
                WHERE `user_id` = :user_id
                  AND `satellite_id` = :satellite_id
            ");
            $stmtDelete->execute([
                ':user_id' => $userId,
                ':satellite_id' => $satelliteId,
            ]);

            $successMessage = 'Der Satellit wurde entfernt.';
        }
    }

    if ($action === 'toggle_satellite_favorite') {
        $satelliteId = (int) ($_POST['satellite_id'] ?? 0);

        if ($satelliteId <= 0) {
            $errors[] = 'Ungueltiger Satellit.';
        }

        if (empty($errors)) {
            if (!setExclusiveFavorite($pdo, 'app_user_satellites', 'satellite_id', $userId, $satelliteId)) {
                $errors[] = 'Der Satellit ist nicht in deiner Liste vorhanden.';
            } else {
                $successMessage = 'Der Satelliten-Favorit wurde aktualisiert.';
            }
        }
    }

    if ($action === 'add_minorplanet') {
        $minorplanetId = (int) ($_POST['minorplanet_id'] ?? 0);

        if ($minorplanetId <= 0) {
            $errors[] = 'Ungueltiger Kleinplanet.';
        }

        if (empty($errors)) {
            $stmtCheck = $pdo->prepare("
                SELECT `id`
                FROM `minorplanets_mpc`
                WHERE `id` = :id
                LIMIT 1
            ");
            $stmtCheck->execute([
                ':id' => $minorplanetId,
            ]);

            if (!$stmtCheck->fetch()) {
                $errors[] = 'Der Kleinplanet wurde nicht gefunden.';
            }
        }

        if (empty($errors)) {
            $stmtInsert = $pdo->prepare("
                INSERT INTO `app_user_minorplanets` (
                    `user_id`,
                    `minorplanet_id`,
                    `is_favorite`,
                    `created_at`
                ) VALUES (
                    :user_id,
                    :minorplanet_id,
                    0,
                    NOW()
                )
                ON DUPLICATE KEY UPDATE
                    `minorplanet_id` = VALUES(`minorplanet_id`)
            ");
            $stmtInsert->execute([
                ':user_id' => $userId,
                ':minorplanet_id' => $minorplanetId,
            ]);

            $successMessage = 'Der Kleinplanet wurde hinzugefuegt.';
        }
    }

    if ($action === 'remove_minorplanet') {
        $minorplanetId = (int) ($_POST['minorplanet_id'] ?? 0);

        if ($minorplanetId <= 0) {
            $errors[] = 'Ungueltiger Kleinplanet.';
        }

        if (empty($errors)) {
            $stmtDelete = $pdo->prepare("
                DELETE FROM `app_user_minorplanets`
                WHERE `user_id` = :user_id
                  AND `minorplanet_id` = :minorplanet_id
            ");
            $stmtDelete->execute([
                ':user_id' => $userId,
                ':minorplanet_id' => $minorplanetId,
            ]);

            $successMessage = 'Der Kleinplanet wurde entfernt.';
        }
    }

    if ($action === 'toggle_minorplanet_favorite') {
        $minorplanetId = (int) ($_POST['minorplanet_id'] ?? 0);

        if ($minorplanetId <= 0) {
            $errors[] = 'Ungueltiger Kleinplanet.';
        }

        if (empty($errors)) {
            if (!setExclusiveFavorite($pdo, 'app_user_minorplanets', 'minorplanet_id', $userId, $minorplanetId)) {
                $errors[] = 'Der Kleinplanet ist nicht in deiner Liste vorhanden.';
            } else {
                $successMessage = 'Der Kleinplaneten-Favorit wurde aktualisiert.';
            }
        }
    }
}

if ($satelliteSearchQuery !== '') {
    if (ctype_digit($satelliteSearchQuery)) {
        $stmtSatelliteSearch = $pdo->prepare("
            SELECT
                s.`id`,
                s.`norad_cat_id`,
                s.`object_name`,
                CASE
                    WHEN aus.`satellite_id` IS NULL THEN 0
                    ELSE 1
                END AS `already_added`
            FROM `sat_satellites` s
            LEFT JOIN `app_user_satellites` aus
                ON aus.`satellite_id` = s.`id`
               AND aus.`user_id` = :user_id
            WHERE s.`norad_cat_id` = :norad_cat_id
            ORDER BY s.`object_name` ASC
            LIMIT 50
        ");
        $stmtSatelliteSearch->execute([
            ':user_id' => $userId,
            ':norad_cat_id' => (int) $satelliteSearchQuery,
        ]);
    } else {
        $stmtSatelliteSearch = $pdo->prepare("
            SELECT
                s.`id`,
                s.`norad_cat_id`,
                s.`object_name`,
                CASE
                    WHEN aus.`satellite_id` IS NULL THEN 0
                    ELSE 1
                END AS `already_added`
            FROM `sat_satellites` s
            LEFT JOIN `app_user_satellites` aus
                ON aus.`satellite_id` = s.`id`
               AND aus.`user_id` = :user_id
            WHERE s.`object_name` LIKE :query
            ORDER BY s.`object_name` ASC
            LIMIT 50
        ");
        $stmtSatelliteSearch->execute([
            ':user_id' => $userId,
            ':query' => '%' . $satelliteSearchQuery . '%',
        ]);
    }

    $satelliteSearchResults = $stmtSatelliteSearch->fetchAll();
}

if ($minorplanetSearchQuery !== '') {
    if (ctype_digit($minorplanetSearchQuery)) {
        $stmtMinorplanetSearch = $pdo->prepare("
            SELECT
                mp.`id`,
                mp.`mp_number`,
                mp.`designation_text`,
                mp.`desig_packed`,
                CASE
                    WHEN aum.`minorplanet_id` IS NULL THEN 0
                    ELSE 1
                END AS `already_added`
            FROM `minorplanets_mpc` mp
            LEFT JOIN `app_user_minorplanets` aum
                ON aum.`minorplanet_id` = mp.`id`
               AND aum.`user_id` = :user_id
            WHERE mp.`mp_number` = :mp_number
            ORDER BY mp.`mp_number` ASC, mp.`designation_text` ASC
            LIMIT 50
        ");
        $stmtMinorplanetSearch->execute([
            ':user_id' => $userId,
            ':mp_number' => (int) $minorplanetSearchQuery,
        ]);
    } else {
        $stmtMinorplanetSearch = $pdo->prepare("
            SELECT
                mp.`id`,
                mp.`mp_number`,
                mp.`designation_text`,
                mp.`desig_packed`,
                CASE
                    WHEN aum.`minorplanet_id` IS NULL THEN 0
                    ELSE 1
                END AS `already_added`
            FROM `minorplanets_mpc` mp
            LEFT JOIN `app_user_minorplanets` aum
                ON aum.`minorplanet_id` = mp.`id`
               AND aum.`user_id` = :user_id
            WHERE mp.`designation_text` LIKE :query
               OR mp.`desig_packed` LIKE :query
            ORDER BY mp.`mp_number` IS NULL ASC, mp.`mp_number` ASC, mp.`designation_text` ASC
            LIMIT 50
        ");
        $stmtMinorplanetSearch->execute([
            ':user_id' => $userId,
            ':query' => '%' . $minorplanetSearchQuery . '%',
        ]);
    }

    $minorplanetSearchResults = $stmtMinorplanetSearch->fetchAll();
}

$stmtTrackedSatellites = $pdo->prepare("
    SELECT
        s.`id`,
        s.`norad_cat_id`,
        s.`object_name`,
        aus.`is_favorite`,
        aus.`created_at`
    FROM `app_user_satellites` aus
    INNER JOIN `sat_satellites` s
        ON s.`id` = aus.`satellite_id`
    WHERE aus.`user_id` = :user_id
    ORDER BY aus.`is_favorite` DESC, s.`object_name` ASC
");
$stmtTrackedSatellites->execute([
    ':user_id' => $userId,
]);
$trackedSatellites = $stmtTrackedSatellites->fetchAll();

$stmtTrackedMinorplanets = $pdo->prepare("
    SELECT
        mp.`id`,
        mp.`mp_number`,
        mp.`designation_text`,
        mp.`desig_packed`,
        aum.`is_favorite`,
        aum.`created_at`
    FROM `app_user_minorplanets` aum
    INNER JOIN `minorplanets_mpc` mp
        ON mp.`id` = aum.`minorplanet_id`
    WHERE aum.`user_id` = :user_id
    ORDER BY aum.`is_favorite` DESC, mp.`mp_number` IS NULL ASC, mp.`mp_number` ASC, mp.`designation_text` ASC
");
$stmtTrackedMinorplanets->execute([
    ':user_id' => $userId,
]);
$trackedMinorplanets = $stmtTrackedMinorplanets->fetchAll();

$loggedIn = true;
?>
<?php require __DIR__ . '/header.php'; ?>

<?php if ($successMessage !== ''): ?>
    <p class="msg-success"><?= h($successMessage) ?></p>
<?php endif; ?>

<?php if (!empty($errors)): ?>
    <ul class="msg-error">
        <?php foreach ($errors as $error): ?>
            <li><?= h($error) ?></li>
        <?php endforeach; ?>
    </ul>
<?php endif; ?>

<div class="grid-2">
    <div class="card">
        <h2>Satelliten suchen</h2>
        <form method="get" action="" class="favorites-loading-form" data-loading-message="Satelliten werden gesucht. Das kann kurz dauern...">
            <div class="input-row">
                <input
                    type="text"
                    id="sat_q"
                    name="sat_q"
                    value="<?= h($satelliteSearchQuery) ?>"
                    placeholder="Name oder NORAD-ID, z. B. ISS oder 25544"
                >
                <button type="submit" class="btn btn-primary">Suchen</button>
            </div>
            <p class="favorites-loading-hint" hidden>Satelliten werden gesucht. Das kann kurz dauern...</p>
        </form>

        <?php if ($satelliteSearchQuery !== ''): ?>
            <div class="mt-xl">
                <h2>Suchergebnisse</h2>
                <?php if (empty($satelliteSearchResults)): ?>
                    <p class="hint">Keine passenden Satelliten gefunden.</p>
                <?php else: ?>
                    <table class="data-table">
                        <thead>
                            <tr>
                                <th>Name</th>
                                <th>NORAD</th>
                                <th></th>
                            </tr>
                        </thead>
                        <tbody>
                            <?php foreach ($satelliteSearchResults as $satellite): ?>
                                <tr>
                                    <td><?= h($satellite['object_name']) ?></td>
                                    <td><?= h((string) $satellite['norad_cat_id']) ?></td>
                                    <td>
                                        <?php if ((int) $satellite['already_added'] === 1): ?>
                                            <span class="hint">Bereits hinzugefuegt</span>
                                        <?php else: ?>
                                            <form method="post" action="" class="favorites-loading-form" data-loading-message="Satellit wird hinzugefuegt...">
                                                <input type="hidden" name="action" value="add_satellite">
                                                <input type="hidden" name="satellite_id" value="<?= (int) $satellite['id'] ?>">
                                                <button type="submit" class="btn btn-sm btn-primary">Hinzufuegen</button>
                                            </form>
                                        <?php endif; ?>
                                    </td>
                                </tr>
                            <?php endforeach; ?>
                        </tbody>
                    </table>
                <?php endif; ?>
            </div>
        <?php endif; ?>
    </div>

    <div class="card">
        <h2>Kleinplaneten suchen</h2>
        <form method="get" action="" class="favorites-loading-form" data-loading-message="Kleinplaneten werden gesucht. Das kann etwas dauern...">
            <div class="input-row">
                <input
                    type="text"
                    id="mp_q"
                    name="mp_q"
                    value="<?= h($minorplanetSearchQuery) ?>"
                    placeholder="Nummer oder Bezeichnung, z. B. 1 oder Ceres"
                >
                <button type="submit" class="btn btn-primary">Suchen</button>
            </div>
            <p class="favorites-loading-hint" hidden>Kleinplaneten werden gesucht. Das kann etwas dauern...</p>
        </form>

        <?php if ($minorplanetSearchQuery !== ''): ?>
            <div class="mt-xl">
                <h2>Suchergebnisse</h2>
                <?php if (empty($minorplanetSearchResults)): ?>
                    <p class="hint">Keine passenden Kleinplaneten gefunden.</p>
                <?php else: ?>
                    <table class="data-table">
                        <thead>
                            <tr>
                                <th>Bezeichnung</th>
                                <th>Nummer</th>
                                <th></th>
                            </tr>
                        </thead>
                        <tbody>
                            <?php foreach ($minorplanetSearchResults as $minorplanet): ?>
                                <tr>
                                    <td><?= h($minorplanet['designation_text'] ?: $minorplanet['desig_packed']) ?></td>
                                    <td><?= h($minorplanet['mp_number'] !== null ? (string) $minorplanet['mp_number'] : '—') ?></td>
                                    <td>
                                        <?php if ((int) $minorplanet['already_added'] === 1): ?>
                                            <span class="hint">Bereits hinzugefuegt</span>
                                        <?php else: ?>
                                            <form method="post" action="" class="favorites-loading-form" data-loading-message="Kleinplanet wird hinzugefuegt...">
                                                <input type="hidden" name="action" value="add_minorplanet">
                                                <input type="hidden" name="minorplanet_id" value="<?= (int) $minorplanet['id'] ?>">
                                                <button type="submit" class="btn btn-sm btn-primary">Hinzufuegen</button>
                                            </form>
                                        <?php endif; ?>
                                    </td>
                                </tr>
                            <?php endforeach; ?>
                        </tbody>
                    </table>
                <?php endif; ?>
            </div>
        <?php endif; ?>
    </div>
</div>

<div class="grid-2">
    <div class="card">
        <h2>Meine Satelliten</h2>
        <?php if (empty($trackedSatellites)): ?>
            <p class="hint">Du hast noch keine Satelliten ausgewaehlt.</p>
        <?php else: ?>
            <table class="data-table">
                <thead>
                    <tr>
                        <th>Name</th>
                        <th>NORAD</th>
                        <th>Favorit</th>
                        <th>Hinzugefuegt</th>
                        <th></th>
                    </tr>
                </thead>
                <tbody>
                    <?php foreach ($trackedSatellites as $satellite): ?>
                        <tr>
                            <td><?= h($satellite['object_name']) ?></td>
                            <td><?= h((string) $satellite['norad_cat_id']) ?></td>
                            <td><?= (int) $satellite['is_favorite'] === 1 ? '*' : '-' ?></td>
                            <td><?= h($satellite['created_at']) ?></td>
                            <td class="action-cell">
                                <form method="post" action="" class="favorites-loading-form" data-loading-message="Satelliten-Favorit wird aktualisiert...">
                                    <input type="hidden" name="action" value="toggle_satellite_favorite">
                                    <input type="hidden" name="satellite_id" value="<?= (int) $satellite['id'] ?>">
                                    <button type="submit" class="btn btn-sm btn-secondary">
                                        <?= (int) $satellite['is_favorite'] === 1 ? 'Favorit entfernen' : 'Als Favorit' ?>
                                    </button>
                                </form>
                                <form method="post" action="" class="favorites-loading-form" data-loading-message="Satellit wird entfernt..." onsubmit="return confirm('Satellit wirklich entfernen?');">
                                    <input type="hidden" name="action" value="remove_satellite">
                                    <input type="hidden" name="satellite_id" value="<?= (int) $satellite['id'] ?>">
                                    <button type="submit" class="btn btn-sm btn-danger">Entfernen</button>
                                </form>
                            </td>
                        </tr>
                    <?php endforeach; ?>
                </tbody>
            </table>
        <?php endif; ?>
    </div>

    <div class="card">
        <h2>Meine Kleinplaneten</h2>
        <?php if (empty($trackedMinorplanets)): ?>
            <p class="hint">Du hast noch keine Kleinplaneten ausgewaehlt.</p>
        <?php else: ?>
            <table class="data-table">
                <thead>
                    <tr>
                        <th>Bezeichnung</th>
                        <th>Nummer</th>
                        <th>Favorit</th>
                        <th>Hinzugefuegt</th>
                        <th></th>
                    </tr>
                </thead>
                <tbody>
                    <?php foreach ($trackedMinorplanets as $minorplanet): ?>
                        <tr>
                            <td><?= h($minorplanet['designation_text'] ?: $minorplanet['desig_packed']) ?></td>
                            <td><?= h($minorplanet['mp_number'] !== null ? (string) $minorplanet['mp_number'] : '-') ?></td>
                            <td><?= (int) $minorplanet['is_favorite'] === 1 ? '*' : '-' ?></td>
                            <td><?= h($minorplanet['created_at']) ?></td>
                            <td class="action-cell">
                                <form method="post" action="" class="favorites-loading-form" data-loading-message="Kleinplaneten-Favorit wird aktualisiert...">
                                    <input type="hidden" name="action" value="toggle_minorplanet_favorite">
                                    <input type="hidden" name="minorplanet_id" value="<?= (int) $minorplanet['id'] ?>">
                                    <button type="submit" class="btn btn-sm btn-secondary">
                                        <?= (int) $minorplanet['is_favorite'] === 1 ? 'Favorit entfernen' : 'Als Favorit' ?>
                                    </button>
                                </form>
                                <form method="post" action="" class="favorites-loading-form" data-loading-message="Kleinplanet wird entfernt..." onsubmit="return confirm('Kleinplanet wirklich entfernen?');">
                                    <input type="hidden" name="action" value="remove_minorplanet">
                                    <input type="hidden" name="minorplanet_id" value="<?= (int) $minorplanet['id'] ?>">
                                    <button type="submit" class="btn btn-sm btn-danger">Entfernen</button>
                                </form>
                            </td>
                        </tr>
                    <?php endforeach; ?>
                </tbody>
            </table>
        <?php endif; ?>
    </div>
</div>

<script>
document.querySelectorAll('.favorites-loading-form').forEach((form) => {
  form.addEventListener('submit', () => {
    const message = form.dataset.loadingMessage || 'Bitte warten...';
    let hint = form.querySelector('.favorites-loading-hint');

    if (!hint) {
      hint = document.createElement('p');
      hint.className = 'favorites-loading-hint';
      form.appendChild(hint);
    }

    hint.textContent = message;
    hint.hidden = false;
    form.classList.add('is-loading');

    form.querySelectorAll('button, input, select, textarea').forEach((field) => {
      if (field.tagName === 'INPUT' && field.type === 'hidden') {
        return;
      }
      field.setAttribute('aria-busy', 'true');
      if (field.tagName === 'BUTTON') {
        field.disabled = true;
      }
    });
  });
});
</script>

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