Rejestr treningów

{
  "trainings": [
    {
      "id": 1,
      "date": "2026-02-10",
      "type": "bieganie",
      "duration": 45,
      "notes": "Bieg w parku, dobra pogoda",
      "created_at": "2026-02-10 18:30:00"
    },
    {
      "id": 2,
      "date": "2026-02-12",
      "type": "siłownia",
      "duration": 60,
      "notes": "Trening górnych partii",
      "created_at": "2026-02-12 20:15:00"
    },
    {
      "id": 3,
      "date": "2026-02-14",
      "type": "rower",
      "duration": 90,
      "notes": "",
      "created_at": "2026-02-14 10:00:00"
    }
  ]
}

$date = $_POST['date'];
$today = date('Y-m-d');

if ($date > $today) {
    $errors[] = "Data nie może być z przyszłości";
}

$duration = filter_var($_POST['duration'], FILTER_VALIDATE_INT);

if ($duration === false || $duration <= 0) {
    $errors[] = "Czas treningu musi być liczbą dodatnią";
}

if ($duration > 480) { // max 8 godzin
    $errors[] = "Czas treningu nie może przekraczać 8 godzin";
}

function calculateTotalTime(array $trainings): int {
    $total = 0;
    foreach ($trainings as $training) {
        $total += $training['duration'];
    }
    return $total;
}

// Formatowanie czasu
function formatDuration(int $minutes): string {
    $hours = floor($minutes / 60);
    $mins = $minutes % 60;

    if ($hours > 0) {
        return "{$hours}h {$mins}min";
    }
    return "{$mins}min";
}

function filterByDateRange(array $trainings, string $from, string $to): array {
    return array_filter($trainings, function($t) use ($from, $to) {
        return $t['date'] >= $from && $t['date'] <= $to;
    });
}

// Ostatni tydzień
$weekAgo = date('Y-m-d', strtotime('-7 days'));
$today = date('Y-m-d');
$thisWeek = filterByDateRange($trainings, $weekAgo, $today);

function countByType(array $trainings): array {
    $counts = [];
    foreach ($trainings as $t) {
        $type = $t['type'];
        $counts[$type] = ($counts[$type] ?? 0) + 1;
    }
    return $counts;
}