<?php
require_once __DIR__ . '/../includes/bootstrap_global.php';

if (!isset($_GET['id']) || !is_numeric($_GET['id'])) {
    http_response_code(400);
    exit('ID praticien invalide.');
}

$praticien_id = intval($_GET['id']);

$stmt = $pdo->prepare("
    SELECT rv.*, c.prenom, c.nom
    FROM rendez_vous rv
    JOIN client c ON rv.client_id = c.id
    WHERE rv.praticien_id = ? AND rv.statut IN ('confirmé', 'prévu')
    ORDER BY rv.date_rdv
");
$stmt->execute([$praticien_id]);
$rdvs = $stmt->fetchAll();

header('Content-Type: text/calendar; charset=utf-8');
header('Content-Disposition: inline; filename="agenda.ics"');

echo "BEGIN:VCALENDAR
";
echo "VERSION:2.0
";
echo "CALSCALE:GREGORIAN
";
echo "METHOD:PUBLISH
";
echo "X-WR-CALNAME:Agenda Praticien
";
echo "X-WR-TIMEZONE:Europe/Paris
";

foreach ($rdvs as $r) {
    // Génération et stockage d’un UUID stable pour éviter les doublons
    if (empty($r['uuid_ical'])) {
        $uuid = bin2hex(random_bytes(16));
        $update = $pdo->prepare("UPDATE rendez_vous SET uuid_ical = ? WHERE id = ?");
        $update->execute([$uuid, $r['id']]);
    } else {
        $uuid = $r['uuid_ical'];
    }

    $start = new DateTime($r['date_rdv'], new DateTimeZone('Europe/Paris'));
    $end = clone $start;
    $end->modify("+" . intval($r['duree_minutes'] ?? 60) . " minutes");

    $summary = "RDV avec {$r['prenom']} {$r['nom']}";

    echo "BEGIN:VEVENT
";
    echo "UID:$uuid
";
    echo "DTSTAMP:" . gmdate('Ymd\THis\Z') . "
";
    echo "DTSTART;TZID=Europe/Paris:" . $start->format('Ymd\THis') . "
";
    echo "DTEND;TZID=Europe/Paris:" . $end->format('Ymd\THis') . "
";
    echo "SUMMARY:$summary
";
    echo "STATUS:CONFIRMED
";
    echo "END:VEVENT
";
}

echo "END:VCALENDAR
";
exit;
?>