<?php
require_once('include/headscript.php');

/**
 * Handler salvataggio evento (insert + update). Riceve il POST di event_form.php,
 * genera lo slug se mancante, valida i campi e fa redirect con ?message=.
 */
if ($_SERVER['REQUEST_METHOD'] !== 'POST') {
    header('Location: events.php');
    exit();
}

$pdo = DBHandlerSelect::getInstance()->getConnection();

// --- ID insegnante loggato -------------------------------------------------
// headscript.php popola $iduserlogin da Auth::user()->present()->id
$currentUserId = $iduserlogin ?? ($_SESSION['iduserlogin'] ?? null);

// --- Helper ----------------------------------------------------------------
function slugify(string $text): string
{
    $text = trim($text);
    if (function_exists('iconv')) {
        $conv = @iconv('UTF-8', 'ASCII//TRANSLIT//IGNORE', $text);
        if ($conv !== false) {
            $text = $conv;
        }
    }
    $text = strtolower($text);
    $text = preg_replace('/[^a-z0-9]+/', '-', $text);
    $text = trim($text, '-');
    return $text !== '' ? $text : 'evento';
}

function uniqueSlug(PDO $pdo, string $base, int $excludeId): string
{
    $slug = $base;
    $i = 2;
    while (true) {
        if ($excludeId > 0) {
            $st = $pdo->prepare("SELECT COUNT(*) FROM events WHERE slug = ? AND id <> ?");
            $st->execute([$slug, $excludeId]);
        } else {
            $st = $pdo->prepare("SELECT COUNT(*) FROM events WHERE slug = ?");
            $st->execute([$slug]);
        }
        if ((int) $st->fetchColumn() === 0) {
            return $slug;
        }
        $slug = $base . '-' . $i;
        $i++;
    }
}

function toDateTime(?string $v): ?string
{
    if (!$v) {
        return null;
    }
    $v  = str_replace('T', ' ', $v);
    $ts = strtotime($v);
    return $ts ? date('Y-m-d H:i:s', $ts) : null;
}

// --- Lettura e validazione input -------------------------------------------
$id    = isset($_POST['id']) ? (int) $_POST['id'] : 0;
$title = trim($_POST['title'] ?? '');

$startsAt = toDateTime($_POST['starts_at'] ?? null);
$maxSeats = (int) ($_POST['max_seats'] ?? 0);

$redirectOnError = $id > 0 ? "event_form.php?id={$id}&message=error" : "event_form.php?message=error";
if ($title === '' || $startsAt === null || $maxSeats < 1) {
    header("Location: {$redirectOnError}");
    exit();
}

$slugInput = trim($_POST['slug'] ?? '');
$slugBase  = slugify($slugInput !== '' ? $slugInput : $title);
$slug      = uniqueSlug($pdo, $slugBase, $id);

$endsAt        = toDateTime($_POST['ends_at'] ?? null);
$address       = trim($_POST['address'] ?? '');
$organizer     = trim($_POST['organizer_name'] ?? '');
$description   = $_POST['description'] ?? '';
$cost          = round((float) ($_POST['cost'] ?? 0), 2);
$maxPerBooking = max(1, (int) ($_POST['max_per_booking'] ?? 1));
$coverImage    = trim($_POST['cover_image'] ?? '');

$lat = ($_POST['lat'] ?? '') !== '' ? (float) $_POST['lat'] : null;
$lng = ($_POST['lng'] ?? '') !== '' ? (float) $_POST['lng'] : null;

$currency = strtoupper(trim($_POST['currency'] ?? 'EUR'));
if (!in_array($currency, ['EUR', 'USD', 'GBP', 'CHF'], true)) {
    $currency = 'EUR';
}

$color = trim($_POST['color'] ?? '#4CAF50');
if (!preg_match('/^#[0-9a-fA-F]{6}$/', $color)) {
    $color = '#4CAF50';
}

$status = $_POST['status'] ?? 'draft';
if (!in_array($status, ['draft', 'published', 'cancelled'], true)) {
    $status = 'draft';
}

// Apertura programmata: se attiva con data futura -> stato 'scheduled' + publish_at
$scheduleEnabled = isset($_POST['schedule_enabled']) && $_POST['schedule_enabled'] === 'Y';
$publishAt = toDateTime($_POST['publish_at'] ?? null);
if ($scheduleEnabled && $publishAt && strtotime($publishAt) > time()) {
    $status = 'scheduled';
} else {
    $publishAt = null; // niente programmazione (o data già passata)
}

// Campi facoltativi (testo)
$instructions = trim($_POST['instructions'] ?? '');
$whatToBring  = trim($_POST['what_to_bring'] ?? '');
$suitableFor  = trim($_POST['suitable_for'] ?? '');

$waitlistEnabled = (isset($_POST['waitlist_enabled']) && $_POST['waitlist_enabled'] === 'Y') ? 'Y' : 'N';

// Override per-evento (NULL = usa default scuola)
$reminderEnabled = (isset($_POST['reminder_enabled']) && in_array($_POST['reminder_enabled'], ['Y', 'N'], true)) ? $_POST['reminder_enabled'] : null;
$reminderHours   = (($_POST['reminder_hours'] ?? '') !== '') ? max(1, min(168, (int) $_POST['reminder_hours'])) : null;
$offerHours      = (($_POST['offer_expiry_hours'] ?? '') !== '') ? max(1, min(336, (int) $_POST['offer_expiry_hours'])) : null;

// Galleria: array JSON di path -> validazione e re-encode pulito
$gallery = null;
$galleryRaw = $_POST['gallery'] ?? '';
if ($galleryRaw !== '') {
    $decoded = json_decode($galleryRaw, true);
    if (is_array($decoded)) {
        $clean = [];
        foreach ($decoded as $p) {
            if (is_string($p) && $p !== '') {
                $clean[] = $p;
            }
        }
        $gallery = !empty($clean) ? json_encode(array_values($clean), JSON_UNESCAPED_SLASHES) : null;
    }
}

// --- Insert / Update -------------------------------------------------------
try {
    if ($id > 0) {
        $sql = "UPDATE events SET
                    title = :title, slug = :slug, description = :description,
                    instructions = :instructions, what_to_bring = :what_to_bring, suitable_for = :suitable_for,
                    organizer_name = :organizer_name, starts_at = :starts_at, ends_at = :ends_at,
                    address = :address, lat = :lat, lng = :lng, cost = :cost, currency = :currency,
                    max_seats = :max_seats, max_per_booking = :max_per_booking, color = :color,
                    waitlist_enabled = :waitlist_enabled,
                    reminder_enabled = :reminder_enabled, reminder_hours = :reminder_hours, offer_expiry_hours = :offer_expiry_hours,
                    cover_image = :cover_image, gallery = :gallery, status = :status, publish_at = :publish_at, updated_at = NOW()
                WHERE id = :id";
        $params = [':id' => $id];
    } else {
        $sql = "INSERT INTO events
                    (user_id, title, slug, description, instructions, what_to_bring, suitable_for,
                     organizer_name, starts_at, ends_at,
                     address, lat, lng, cost, currency, max_seats, max_per_booking, color,
                     waitlist_enabled,
                     reminder_enabled, reminder_hours, offer_expiry_hours,
                     cover_image, gallery, status, publish_at, created_at, updated_at)
                VALUES
                    (:user_id, :title, :slug, :description, :instructions, :what_to_bring, :suitable_for,
                     :organizer_name, :starts_at, :ends_at,
                     :address, :lat, :lng, :cost, :currency, :max_seats, :max_per_booking, :color,
                     :waitlist_enabled,
                     :reminder_enabled, :reminder_hours, :offer_expiry_hours,
                     :cover_image, :gallery, :status, :publish_at, NOW(), NOW())";
        $params = [':user_id' => $currentUserId];
    }

    $params += [
        ':title'           => $title,
        ':slug'            => $slug,
        ':description'     => $description !== '' ? $description : null,
        ':instructions'    => $instructions !== '' ? $instructions : null,
        ':what_to_bring'   => $whatToBring !== '' ? $whatToBring : null,
        ':suitable_for'    => $suitableFor !== '' ? $suitableFor : null,
        ':organizer_name'  => $organizer !== '' ? $organizer : null,
        ':starts_at'       => $startsAt,
        ':ends_at'         => $endsAt,
        ':address'         => $address !== '' ? $address : null,
        ':lat'             => $lat,
        ':lng'             => $lng,
        ':cost'            => $cost,
        ':currency'        => $currency,
        ':max_seats'       => $maxSeats,
        ':max_per_booking' => $maxPerBooking,
        ':waitlist_enabled' => $waitlistEnabled,
        ':reminder_enabled' => $reminderEnabled,
        ':reminder_hours'   => $reminderHours,
        ':offer_expiry_hours' => $offerHours,
        ':color'           => $color,
        ':cover_image'     => $coverImage !== '' ? $coverImage : null,
        ':gallery'         => $gallery,
        ':publish_at'      => $publishAt,
        ':status'          => $status,
    ];

    $stmt = $pdo->prepare($sql);
    $stmt->execute($params);

    header('Location: events.php?message=success');
    exit();
} catch (Throwable $ex) {
    error_log('[event_save] ' . $ex->getMessage());
    header("Location: {$redirectOnError}");
    exit();
}