<?php
require_once __DIR__ . '/bootstrap.php';

/**
 * Endpoint pubblico LISTA eventi (sola lettura).
 * Ritorna gli eventi PUBBLICATI e NON ancora terminati, con posti/prezzo/gallery.
 *
 * Parametri (query string):
 *   ?id=12          -> un solo evento
 *   ?ids=12,15,20   -> solo questi eventi (nell'ordine per data)
 *   ?limit=3        -> massimo N eventi
 * Senza parametri: tutti i pubblicati futuri, per data crescente.
 *
 * Regole di visibilità:
 *   status = 'published' AND COALESCE(ends_at, starts_at) >= NOW()
 * (l'evento sparisce da solo quando è terminato)
 */
try {
    $pdo = pdo_conn();

    $id       = isset($_GET['id']) ? (int) $_GET['id'] : 0;
    $idsParam = trim($_GET['ids'] ?? '');
    $limit    = isset($_GET['limit']) ? max(1, min(50, (int) $_GET['limit'])) : 0;

    $where  = ["e.status = 'published'", "COALESCE(e.ends_at, e.starts_at) >= NOW()"];
    $params = [];

    if ($id > 0) {
        $where[]  = 'e.id = ?';
        $params[] = $id;
    } elseif ($idsParam !== '') {
        $ids = array_values(array_filter(array_map('intval', explode(',', $idsParam)), function ($v) {
            return $v > 0;
        }));
        if (!empty($ids)) {
            $where[] = 'e.id IN (' . implode(',', array_fill(0, count($ids), '?')) . ')';
            foreach ($ids as $v) {
                $params[] = $v;
            }
        } else {
            send_json(['ok' => true, 'count' => 0, 'events' => []]);
        }
    }

    $sql = "SELECT e.*, u.first_name AS cf, u.last_name AS cl,
                   COALESCE(b.occupied, 0) AS occupied,
                   COALESCE(w.waiting, 0)  AS waiting
            FROM events e
            LEFT JOIN auth_users u ON u.id = e.user_id
            LEFT JOIN (
                SELECT event_id, SUM(seats) AS occupied
                FROM event_bookings WHERE status IN ('confirmed','pending','offered')
                GROUP BY event_id
            ) b ON b.event_id = e.id
            LEFT JOIN (
                SELECT event_id, SUM(seats) AS waiting
                FROM event_bookings WHERE status = 'waiting'
                GROUP BY event_id
            ) w ON w.event_id = e.id
            WHERE " . implode(' AND ', $where) . "
            ORDER BY e.starts_at ASC";

    if ($limit > 0) {
        $sql .= ' LIMIT ' . (int) $limit;
    }

    $stmt = $pdo->prepare($sql);
    $stmt->execute($params);
    $rows = $stmt->fetchAll(PDO::FETCH_ASSOC);

    $symbols = ['EUR' => '€', 'USD' => '$', 'GBP' => '£', 'CHF' => 'CHF'];
    $events  = [];

    foreach ($rows as $r) {
        $maxSeats  = (int) $r['max_seats'];
        $occupied  = (int) $r['occupied'];
        $remaining = max(0, $maxSeats - $occupied);

        $gallery = [];
        if (!empty($r['gallery'])) {
            $g = json_decode($r['gallery'], true);
            if (is_array($g)) {
                foreach ($g as $path) {
                    if (is_string($path) && $path !== '') {
                        $gallery[] = public_url($path);
                    }
                }
            }
        }

        $organizer = trim((string) $r['organizer_name']) !== ''
            ? $r['organizer_name']
            : trim(($r['cf'] ?? '') . ' ' . ($r['cl'] ?? ''));

        $events[] = [
            'id'               => (int) $r['id'],
            'title'            => $r['title'],
            'slug'             => $r['slug'],
            'description'      => $r['description'],       // HTML (sanificare al rendering in WP)
            'instructions'     => $r['instructions'],
            'what_to_bring'    => $r['what_to_bring'],
            'suitable_for'     => $r['suitable_for'],
            'organizer'        => $organizer !== '' ? $organizer : null,
            'starts_at'        => $r['starts_at'],
            'ends_at'          => $r['ends_at'],
            'address'          => $r['address'],
            'lat'              => $r['lat'] !== null ? (float) $r['lat'] : null,
            'lng'              => $r['lng'] !== null ? (float) $r['lng'] : null,
            'cost'             => (float) $r['cost'],
            'currency'         => $r['currency'],
            'currency_symbol'  => $symbols[$r['currency']] ?? $r['currency'],
            'color'            => $r['color'],
            'cover_image'      => public_url($r['cover_image']),
            'gallery'          => $gallery,
            'max_seats'        => $maxSeats,
            'max_per_booking'  => (int) $r['max_per_booking'],
            'occupied'         => $occupied,
            'remaining'        => $remaining,
            'sold_out'         => $remaining <= 0,
            'waitlist_enabled' => ($r['waitlist_enabled'] ?? 'N') === 'Y',
            'waiting'          => (int) $r['waiting'],
        ];
    }

    send_json(['ok' => true, 'count' => count($events), 'events' => $events]);
} catch (Throwable $ex) {
    error_log('[api/events] ' . $ex->getMessage());
    send_json(['ok' => false, 'error' => 'Errore nel recupero degli eventi.'], 500);
}