<?php

declare(strict_types=1);

namespace TFGraphics\SmartImport\Knowledge;

final class KnowledgeVersion
{
    private int $number;
    private string $hash;
    private \DateTimeImmutable $createdAt;

    public function __construct(int $number, string $hash, \DateTimeImmutable $createdAt)
    {
        if ($number < 1) {
            throw new \InvalidArgumentException('Knowledge version must be greater than zero.');
        }

        $this->number = $number;
        $this->hash = $hash;
        $this->createdAt = $createdAt;
    }

    public function getNumber(): int
    {
        return $this->number;
    }

    public function getHash(): string
    {
        return $this->hash;
    }

    public function getCreatedAt(): \DateTimeImmutable
    {
        return $this->createdAt;
    }

    public function next(string $hash, \DateTimeImmutable $createdAt): self
    {
        return new self($this->number + 1, $hash, $createdAt);
    }
}