<?php

class AssignPullRequestReviewerCommandHandler implements CommandHandler
{
    /**
     * @var PullRequestRepository
     */
    private $repository;

    public function __construct(PullRequestRepository $repository)
    {
        $this->repository = $repository;
    }

    /**
     * @param AssignPullRequestReviewerCommand $command
     */
    public function handle(Command $command): void
    {
        $pullRequest = $this->repository->findOfId($command->aggregateRootId());

        if (!$command->reviewer()) {
            return EventStream::fromDomainEvents(new PullRequestReviewerAssignationFailed($command->aggregateRootId(), $command->reviewer(), PullRequestReviewerAssignationFailed::EMPTY_REVIEWER));
        }

        if (2 === count($pullRequest->assignedReviewers())) {
            return EventStream::fromDomainEvents(new PullRequestReviewerAssignationFailed($command->aggregateRootId(), $command->reviewer(), PullRequestReviewerAssignationFailed::MAX_REVIEWERS_ASSIGNED));
        }

        if (in_array($command->reviewer(), $pullRequest->assignedReviewers())) {
            return EventStream::fromDomainEvents(new PullRequestReviewerAssignationFailed($command->aggregateRootId(), $command->reviewer(), PullRequestReviewerAssignationFailed::REVIEWER_ALREADY_ASSIGNED));
        }

        $this->repository->saveEventStream(EventStream::fromDomainEvents(new PullRequestReviewerAssigned($command->aggregateRootId(), $command->reviewer())));
    }
}