dry.example.3.php

abstract class ProducePdfHandler
{
    private $pdfGenerator;
    private $dataProvider;
    
    public function __construct(
        PdfGenerator $pdfGenerator,
        DefaultDataProvider $dataProvider
    ) {
        $this->pdfGenerator = $pdfGenerator;
        $this->dataProvider = $dataProvider;
    }
    
    abstract public function invoke(Comamnd $command): PdfId;
    
    private function produce(Command $command, PdfTemplate $template): PdfId
    {
        $data = $this->dataProvider->provide($command->accountId());
        $id = $this->pdfGenerator->generate($template, $data);
        return $id;
    }
}

final class ProduceStatementOfAccountHandler extends ProducePdfHandler
{
    public function invoke(Comamnd $command): PdfId
    {
        return $this->produce(PdfTemplate::STATEMENT_OF_ACCOUNT);
    }
}

final class ProducePaymentOverdueHandler extends ProducePdfHandler
{
    public function invoke(Comamnd $command): PdfId
    {
        return $this->produce(PdfTemplate::PAYMENT_OVERDUE);
    }
}