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


if (!isset($_GET['praticien_id'])) {
    http_response_code(400);
    echo json_encode(['error' => $translations['id_praticien_manquant']]);
    exit;
}

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

// Récupérer la durée d'un rendez-vous
$stmt = $pdo->prepare("SELECT duree_rdv FROM praticien WHERE id = ?");
$stmt->execute([$praticien_id]);
$duree_minutes = (int)$stmt->fetchColumn();
if (!$duree_minutes) {
    echo json_encode([]);
    exit;
}

$date_debut = new DateTimeImmutable();
$date_fin = $date_debut->modify('+3 weeks');

// Récupérer toutes les disponibilités du praticien
$stmt = $pdo->prepare("SELECT jour_semaine, heure_debut, heure_fin FROM disponibilite WHERE praticien_id = ?");
$stmt->execute([$praticien_id]);
$dispos = $stmt->fetchAll(PDO::FETCH_ASSOC);

// Récupérer tous les rendez-vous déjà réservés dans cette période
$stmt = $pdo->prepare("SELECT date_rdv FROM rendez_vous WHERE praticien_id = ? AND date_rdv BETWEEN ? AND ?");
$stmt->execute([$praticien_id, $date_debut->format('Y-m-d H:i:s'), $date_fin->format('Y-m-d H:i:s')]);
$reservations_existantes = array_map(function($r) {
    return (new DateTimeImmutable($r['date_rdv']))->format('Y-m-d H:i');
}, $stmt->fetchAll(PDO::FETCH_ASSOC));

$events = [];

$periode = new DatePeriod(
    $date_debut,
    new DateInterval('P1D'),
    $date_fin
);

foreach ($periode as $jour) {
    $jour_semaine = (int)$jour->format('N'); // 1 = lundi, 7 = dimanche


    foreach ($dispos as $dispo) {
        if ((int)$dispo['jour_semaine'] !== $jour_semaine) continue;

        $heure_debut = DateTime::createFromFormat('H:i:s', $dispo['heure_debut']);
        $heure_fin = DateTime::createFromFormat('H:i:s', $dispo['heure_fin']);
        if (!$heure_debut || !$heure_fin) continue;

        $debut_creneau = (new DateTimeImmutable($jour->format('Y-m-d') . ' ' . $heure_debut->format('H:i:s')));
        $fin_creneau = (new DateTimeImmutable($jour->format('Y-m-d') . ' ' . $heure_fin->format('H:i:s')));

        while ($debut_creneau->add(new DateInterval('PT' . $duree_minutes . 'M')) <= $fin_creneau) {
            $fin = $debut_creneau->add(new DateInterval('PT' . $duree_minutes . 'M'));
            $start_str = $debut_creneau->format('Y-m-d H:i');

            if (!in_array($start_str, $reservations_existantes)) {
                $events[] = [
                    'title' => $debut_creneau->format('H:i'),
                    'start' => $debut_creneau->format(DateTime::ATOM),
                    'end'   => $fin->format(DateTime::ATOM)
                ];
            }

            $debut_creneau = $fin;
        }
    }
}

header('Content-Type: application/json');
echo json_encode($events);