<?php

namespace Tests\Unit\Post\UseCases;

use App\Exceptions\BadRequestException;
use App\Post\CreatePostDto;
use App\Post\Post;
use App\Post\UseCases\GetPost\GetPost;
use DateTimeImmutable;
use DateTimeZone;
use Tests\Fakes\FakePostRepository;
use Tests\TestCase;

class GetPostTest extends TestCase
{
    private FakePostRepository $postRepo;

    private DateTimeImmutable $now;

    private GetPost $useCase;

    protected function setUp(): void
    {
        $this->now = new DateTimeImmutable(
            '2026-05-06T12:00:00',
            new DateTimeZone('UTC')
        );
        $this->postRepo = new FakePostRepository;
        $this->useCase = new GetPost($this->postRepo);
    }

    public function test_zero_id_throws_bad_request(): void
    {
        $this->expectException(BadRequestException::class);
        $this->useCase->execute(0);
    }

    public function test_negative_id_throws_bad_request(): void
    {
        $this->expectException(BadRequestException::class);
        $this->useCase->execute(-5);
    }

    public function test_unknown_id_returns_null(): void
    {
        $result = $this->useCase->execute(999);

        $this->assertNull($result);
    }

    public function test_existing_id_returns_post(): void
    {
        $created = $this->postRepo->create(new CreatePostDto(
            userId: 7,
            title: 'My Post',
            body: 'Some body content.',
            createdAt: $this->now,
        ));

        $result = $this->useCase->execute($created->getId());

        $this->assertInstanceOf(Post::class, $result);
        $this->assertSame('My Post', $result->getTitle());
        $this->assertSame(7, $result->getUserId());
    }
}