<?php

namespace Tests\Unit\Post\UseCases;

use App\Exceptions\BadRequestException;
use App\Exceptions\ForbiddenException;
use App\Post\CreatePostDto;
use App\Post\Post;
use App\Post\UseCases\DeletePost\DeletePost;
use App\Post\UseCases\DeletePost\DeletePostRequest;
use DateTimeImmutable;
use DateTimeZone;
use Tests\Fakes\FakePostRepository;
use Tests\TestCase;

class DeletePostTest extends TestCase
{
    private FakePostRepository $postRepo;

    private DateTimeImmutable $now;

    private DeletePost $useCase;

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

    private function seedPostByUser(int $userId): Post
    {
        return $this->postRepo->create(new CreatePostDto(
            userId: $userId,
            title: 'Some Post',
            body: 'Some body.',
            createdAt: $this->now,
        ));
    }

    public function test_zero_post_id_throws_bad_request(): void
    {
        $this->expectException(BadRequestException::class);
        $this->useCase->execute(new DeletePostRequest(
            postId: 0,
            requesterId: 1,
            requesterIsAdmin: false,
        ));
    }

    public function test_zero_requester_id_throws_bad_request(): void
    {
        $post = $this->seedPostByUser(1);

        $this->expectException(BadRequestException::class);
        $this->useCase->execute(new DeletePostRequest(
            postId: $post->getId(),
            requesterId: 0,
            requesterIsAdmin: false,
        ));
    }

    public function test_unknown_post_is_no_op(): void
    {
        $this->useCase->execute(new DeletePostRequest(
            postId: 999,
            requesterId: 1,
            requesterIsAdmin: false,
        ));

        // No exception thrown -> idempotent delete on missing post.
        $this->assertNull($this->postRepo->find(999));
    }

    public function test_author_can_delete_own_post(): void
    {
        $post = $this->seedPostByUser(1);

        $this->useCase->execute(new DeletePostRequest(
            postId: $post->getId(),
            requesterId: 1,
            requesterIsAdmin: false,
        ));

        $this->assertNull($this->postRepo->find($post->getId()));
    }

    public function test_admin_can_delete_anyones_post(): void
    {
        $post = $this->seedPostByUser(1);

        $this->useCase->execute(new DeletePostRequest(
            postId: $post->getId(),
            requesterId: 99,
            requesterIsAdmin: true,
        ));

        $this->assertNull($this->postRepo->find($post->getId()));
    }

    public function test_other_user_cannot_delete_post(): void
    {
        $post = $this->seedPostByUser(1);

        $this->expectException(ForbiddenException::class);
        $this->useCase->execute(new DeletePostRequest(
            postId: $post->getId(),
            requesterId: 2,
            requesterIsAdmin: false,
        ));
    }

    public function test_forbidden_delete_does_not_remove_post(): void
    {
        $post = $this->seedPostByUser(1);

        try {
            $this->useCase->execute(new DeletePostRequest(
                postId: $post->getId(),
                requesterId: 2,
                requesterIsAdmin: false,
            ));
        } catch (ForbiddenException) {
            // expected
        }

        $this->assertNotNull($this->postRepo->find($post->getId()));
    }
}