<?php
session_start();
require_once(__DIR__ . '/../inc/config.inc.php');
require_once(__DIR__ . '/../inc/functions.inc.php');

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

$user = check_user();
$isAdmin = is_admin_user();

$start = $_GET['start'] ?? null;
$end = $_GET['end'] ?? null;
$onlyApproved = isset($_GET['only_approved']) && ($_GET['only_approved'] == '1' || $_GET['only_approved'] === 'true');
$public = isset($_GET['public']) && ($_GET['public'] == '1' || $_GET['public'] === 'true');
$includeRejected = isset($_GET['include_rejected']) && ($_GET['include_rejected'] == '1' || $_GET['include_rejected'] === 'true');
$onlyPersonal = isset($_GET['only_personal']) && ($_GET['only_personal'] == '1' || $_GET['only_personal'] === 'true');
$publicAll = isset($_GET['public_all']) && ($_GET['public_all'] == '1' || $_GET['public_all'] === 'true');

if (!$start || !$end) {
    http_response_code(400);
    echo json_encode(['error' => 'start and end required']);
    exit;
}

$events = [];
try {
    $branch = 'unknown';
    $debugMode = isset($_GET['debug']) && ($_GET['debug'] == '1' || $_GET['debug'] === 'true');
    $showEmployeeNames = $isAdmin || $public;

    if ($onlyPersonal) {
        $branch = 'onlyPersonal';
        if ($onlyApproved) {
            $branch = 'onlyPersonal_onlyApproved';
            $stmt = $pdo->prepare("SELECT v.*, u.vorname, u.nachname FROM vacations v JOIN users u ON v.user_id = u.id WHERE v.user_id = ? AND v.start_date <= ? AND v.end_date >= ? AND LOWER(TRIM(v.status)) = 'genehmigt' ORDER BY v.start_date");
            $stmt->execute([$_SESSION['userid'], $end, $start]);
        } else {
            if ($includeRejected) {
                $branch = 'onlyPersonal_includeRejected';
                $stmt = $pdo->prepare("SELECT v.*, u.vorname, u.nachname FROM vacations v JOIN users u ON v.user_id = u.id WHERE v.user_id = ? AND v.start_date <= ? AND v.end_date >= ? ORDER BY v.start_date");
                $stmt->execute([$_SESSION['userid'], $end, $start]);
            } else {
                $branch = 'onlyPersonal_excludeRejected';
                $stmt = $pdo->prepare("SELECT v.*, u.vorname, u.nachname FROM vacations v JOIN users u ON v.user_id = u.id WHERE v.user_id = ? AND v.start_date <= ? AND v.end_date >= ? AND (v.status IS NULL OR LOWER(TRIM(v.status)) != 'abgelehnt') ORDER BY v.start_date");
                $stmt->execute([$_SESSION['userid'], $end, $start]);
            }
        }
    } elseif ($isAdmin) {
        $branch = 'admin';
        if ($onlyApproved) {
            $branch = 'admin_onlyApproved';
            $stmt = $pdo->prepare("SELECT v.*, u.vorname, u.nachname FROM vacations v JOIN users u ON v.user_id = u.id WHERE v.start_date <= ? AND v.end_date >= ? AND LOWER(TRIM(v.status)) = 'genehmigt' ORDER BY v.start_date");
            $stmt->execute([$end, $start]);
        } else {
            if ($includeRejected) {
                $stmt = $pdo->prepare("SELECT v.*, u.vorname, u.nachname FROM vacations v JOIN users u ON v.user_id = u.id WHERE v.start_date <= ? AND v.end_date >= ? ORDER BY v.start_date");
                $stmt->execute([$end, $start]);
            } else {
                $stmt = $pdo->prepare("SELECT v.*, u.vorname, u.nachname FROM vacations v JOIN users u ON v.user_id = u.id WHERE v.start_date <= ? AND v.end_date >= ? AND (v.status IS NULL OR LOWER(TRIM(v.status)) IN ('genehmigt','beantragt')) ORDER BY v.start_date");
                $stmt->execute([$end, $start]);
            }
        }
    } else {
        $branch = 'public_or_regular';
        if ($public && $onlyApproved) {
            $branch = 'public_onlyApproved';
            $stmt = $pdo->prepare("SELECT v.*, u.vorname, u.nachname FROM vacations v JOIN users u ON v.user_id = u.id WHERE v.start_date <= ? AND v.end_date >= ? AND LOWER(TRIM(v.status)) = 'genehmigt' ORDER BY v.start_date");
            $stmt->execute([$end, $start]);
        } elseif ($public && $publicAll) {
            $branch = 'public_publicAll';
            $stmt = $pdo->prepare("SELECT v.*, u.vorname, u.nachname FROM vacations v JOIN users u ON v.user_id = u.id WHERE v.start_date <= ? AND v.end_date >= ? AND (v.status IS NULL OR LOWER(TRIM(v.status)) IN ('genehmigt','beantragt')) ORDER BY v.start_date");
            $stmt->execute([$end, $start]);
        } else {
            if ($onlyApproved) {
                $stmt = $pdo->prepare("SELECT v.*, u.vorname, u.nachname FROM vacations v JOIN users u ON v.user_id = u.id WHERE v.user_id = ? AND v.start_date <= ? AND v.end_date >= ? AND LOWER(TRIM(v.status)) = 'genehmigt' ORDER BY v.start_date");
                $stmt->execute([$_SESSION['userid'], $end, $start]);
            } else {
                if ($includeRejected) {
                    $branch = 'regular_includeRejected';
                    $stmt = $pdo->prepare("SELECT v.*, u.vorname, u.nachname FROM vacations v JOIN users u ON v.user_id = u.id WHERE v.user_id = ? AND v.start_date <= ? AND v.end_date >= ? ORDER BY v.start_date");
                    $stmt->execute([$_SESSION['userid'], $end, $start]);
                } else {
                    $branch = 'regular_excludeRejected';
                    $stmt = $pdo->prepare("SELECT v.*, u.vorname, u.nachname FROM vacations v JOIN users u ON v.user_id = u.id WHERE v.user_id = ? AND v.start_date <= ? AND v.end_date >= ? AND (v.status IS NULL OR LOWER(TRIM(v.status)) != 'abgelehnt') ORDER BY v.start_date");
                    $stmt->execute([$_SESSION['userid'], $end, $start]);
                }
            }
        }
    }

    try {
        $vacations = $stmt->fetchAll(PDO::FETCH_ASSOC);

        if ($debugMode) {
            $rawStatuses = array_map(function($r){ return $r['status'] ?? null; }, $vacations);
            $meta = [
                'branch' => $branch,
                'count' => count($vacations),
                'raw_statuses' => $rawStatuses
            ];
        }

        foreach ($vacations as $v) {
            if (isset($v['status'])) {
                $normalized = preg_replace('/\s+/u', ' ', $v['status']);
                $status = mb_strtolower(trim($normalized));
            } else {
                $status = '';
            }

            if (!$isAdmin && !$includeRejected && mb_stripos($status, 'abgelehnt') !== false) {
                continue;
            }

            $isApproved = (mb_stripos($status, 'genehmigt') !== false);
            $employeeName = trim(($v['vorname'] ?? '') . ' ' . ($v['nachname'] ?? ''));
            if ($showEmployeeNames && $employeeName !== '') {
                $title = $employeeName;
                if ($v['status'] !== null && $v['status'] !== '') {
                    $title .= ' (' . $v['status'] . ')';
                }
            } elseif ($isApproved) {
                $title = 'Urlaub';
            } else {
                $title = 'Urlaubsantrag';
            }

            try {
                $endInclusive = (new DateTime($v['end_date']))->modify('+1 day')->format('Y-m-d');
            } catch (Exception $e) {
                $endInclusive = $v['start_date'];
            }

            $events[] = [
                'id' => 'vac_' . $v['id'],
                'title' => $title,
                'start' => $v['start_date'],
                'end' => $endInclusive,
                'allDay' => true,
                'color' => ($isApproved) ? '#28a745' : '#ffc107',
                'extendedProps' => [
                    'type' => 'user',
                    'user_id' => $v['user_id'],
                    'employee_name' => $employeeName,
                    'status' => $v['status'],
                    'comment' => $v['comment_user'] ?? ''
                ]
            ];
        }
    } catch (Exception $ex) {
        header('Content-Type: application/json; charset=utf-8');
        $payload = ['error' => $ex->getMessage(), 'branch' => $branch, 'trace' => $ex->getTraceAsString()];
        echo json_encode($payload);
        exit;
    }
} catch (Exception $ex) {
    header('Content-Type: application/json; charset=utf-8');
    $payload = ['error' => $ex->getMessage(), 'branch' => $branch, 'trace' => $ex->getTraceAsString()];
    echo json_encode($payload);
    exit;
}

$stmt = $pdo->prepare("SELECT * FROM company_holidays WHERE start_date <= ? AND end_date >= ? ORDER BY start_date");
$stmt->execute([$end, $start]);
$holidays = $stmt->fetchAll(PDO::FETCH_ASSOC);

foreach ($holidays as $h) {
    $endInclusive = (new DateTime($h['end_date']))->modify('+1 day')->format('Y-m-d');
    $events[] = [
        'id' => 'com_' . $h['id'],
        'title' => $h['description'] ?: 'Betriebsurlaub',
        'start' => $h['start_date'],
        'end' => $endInclusive,
        'allDay' => true,
        'color' => '#007bff',
        'extendedProps' => [
            'type' => 'company',
            'description' => $h['description']
        ]
    ];
}

header('Content-Type: application/json; charset=utf-8');
if ($debugMode) {
    echo json_encode(['events' => $events, 'meta' => $meta]);
} else {
    echo json_encode($events);
}
?>