Support Contracts（Arrayable / Jsonable / Htmlable / Responsable）

interface Arrayable
{
    public function toArray();
}

use Illuminate\Contracts\Support\Arrayable;

final class Money implements Arrayable
{
    public function __construct(
        public readonly int $amount,
        public readonly string $currency,
    ) {}

    public function toArray(): array
    {
        return [
            'amount' => $this->amount,
            'currency' => $this->currency,
        ];
    }
}

interface Jsonable
{
    public function toJson($options = 0);
}

use Illuminate\Contracts\Support\Jsonable;

final class ApiPayload implements Jsonable
{
    public function __construct(
        private array $data,
    ) {}

    public function toJson($options = 0): string
    {
        return json_encode([
            'data' => $this->data,
            'generated_at' => now()->toIso8601String(),
        ], $options | JSON_THROW_ON_ERROR);
    }
}

interface Htmlable
{
    public function toHtml();
}

use Illuminate\Contracts\Support\Htmlable;

final class BadgeHtml implements Htmlable
{
    public function __construct(
        private string $label,
    ) {}

    public function toHtml(): string
    {
        $escaped = e($this->label);

        return "<span class=\"badge\">{$escaped}</span>";
    }
}

interface Responsable
{
    public function toResponse($request);
}

use Illuminate\Contracts\Support\Responsable;

final class ExportCsvResponse implements Responsable
{
    public function __construct(
        private array $rows,
        private string $filename = 'export.csv',
    ) {}

    /**
     * @param \Illuminate\Http\Request $request
     */
    public function toResponse($request)
    {
        return response()->streamDownload(function () {
            $stream = fopen('php://output', 'w');

            foreach ($this->rows as $row) {
                fputcsv($stream, $row);
            }

            fclose($stream);
        }, $this->filename, [
            'Content-Type' => 'text/csv',
        ]);
    }
}