<?php
declare(strict_types=1);

class TaskCertRequest
{
    public static function method(): string
    {
        return strtoupper((string) ($_SERVER['REQUEST_METHOD'] ?? 'GET'));
    }

    public static function isPost(): bool
    {
        return self::method() === 'POST';
    }

    public static function postString(string $key, string $default = ''): string
    {
        $value = $_POST[$key] ?? $default;
        if (is_array($value)) {
            return $default;
        }

        return trim((string) $value);
    }

    public static function postInt(string $key, int $default = 0): int
    {
        return (int) ($_POST[$key] ?? $default);
    }

    public static function postArray(string $key): array
    {
        $value = $_POST[$key] ?? [];
        return is_array($value) ? $value : [];
    }

    public static function postIntArray(string $key): array
    {
        $items = self::postArray($key);
        $result = [];

        $collect = static function ($value) use (&$collect, &$result): void {
            if (is_array($value)) {
                foreach ($value as $nestedValue) {
                    $collect($nestedValue);
                }
                return;
            }

            $itemInt = (int) $value;
            if ($itemInt > 0) {
                $result[] = $itemInt;
            }
        };

        foreach ($items as $item) {
            $collect($item);
        }

        return array_values(array_unique($result));
    }

    public static function queryString(string $key, string $default = ''): string
    {
        $value = $_GET[$key] ?? $default;
        if (is_array($value)) {
            return $default;
        }

        return trim((string) $value);
    }

    public static function queryInt(string $key, int $default = 0): int
    {
        return (int) ($_GET[$key] ?? $default);
    }

    public static function jsonBody(): array
    {
        $raw = file_get_contents('php://input');
        if ($raw === false || $raw === '') {
            return [];
        }

        $decoded = json_decode($raw, true);
        if (!is_array($decoded)) {
            return [];
        }

        return $decoded;
    }
}