<?php

namespace Tests\Unit\Set\UseCases;

use App\Element\CreateElementDto;
use App\Exceptions\NotFoundException;
use App\Set\CreateSetDto;
use App\Set\CreateSetLevelDto;
use App\Set\UseCases\GetSetLayout\ElementLayoutNode;
use App\Set\UseCases\GetSetLayout\GetSetLayout;
use App\Set\UseCases\GetSetLayout\GetSetLayoutRequest;
use App\Shared\ValueObject\EmailAddress;
use App\User\User;
use PHPUnit\Framework\TestCase;
use Tests\Fakes\FakeElementRepository;
use Tests\Fakes\FakeSetRepository;
use Tests\Fakes\FakeSetLevelRepository;

class GetSetLayoutTest extends TestCase
{
    public function test_it_builds_an_ordered_element_tree(): void
    {
        $creator = new User(
            id: 7,
            email: new EmailAddress('creator@example.com'),
            passwordHash: 'hashed-password',
        );
        $setRepository = new FakeSetRepository;
        $setLevelRepository = new FakeSetLevelRepository;
        $elementRepository = new FakeElementRepository;
        $bible = $setRepository->create(new CreateSetDto(
            name: 'Bible',
            creator: $creator,
        ));
        $course = $setRepository->create(new CreateSetDto(
            name: 'Course',
            creator: $creator,
        ));
        $bookLevel = $setLevelRepository->create(new CreateSetLevelDto(
            set: $bible,
            kind: 'book',
        ));
        $portionLevel = $setLevelRepository->create(new CreateSetLevelDto(
            set: $bible,
            kind: 'portion',
        ));
        $chapterLevel = $setLevelRepository->create(new CreateSetLevelDto(
            set: $bible,
            kind: 'chapter',
        ));
        $moduleLevel = $setLevelRepository->create(new CreateSetLevelDto(
            set: $course,
            kind: 'module',
        ));
        $genesis = $elementRepository->create(new CreateElementDto(
            name: 'Genesis',
            level: $bookLevel,
            parentElement: null,
        ));
        $elementRepository->create(new CreateElementDto(
            name: 'Exodus',
            level: $bookLevel,
            parentElement: null,
        ));
        $creation = $elementRepository->create(new CreateElementDto(
            name: 'Creation',
            level: $portionLevel,
            parentElement: $genesis,
        ));
        $elementRepository->create(new CreateElementDto(
            name: 'Noah',
            level: $portionLevel,
            parentElement: $genesis,
        ));
        $elementRepository->create(new CreateElementDto(
            name: 'Chapter 1',
            level: $chapterLevel,
            parentElement: $creation,
        ));
        $elementRepository->create(new CreateElementDto(
            name: 'Foundations',
            level: $moduleLevel,
            parentElement: null,
        ));

        $layout = (new GetSetLayout(
            $setRepository,
            $setLevelRepository,
            $elementRepository,
        ))->execute(new GetSetLayoutRequest(
            setId: $bible->getId(),
        ));

        $this->assertSame('Bible', $layout->getSet()->getName());
        $this->assertSame(
            ['book:2', 'portion:2', 'chapter:1'],
            array_map(function ($level): string {
                return $level->getLevel()->getKind()
                    . ":{$level->getElementCount()}";
            }, $layout->getLevels()),
        );
        $this->assertSame(
            ['Genesis', 'Exodus'],
            $this->nodeNames($layout->getElements()),
        );
        $genesisNode = $layout->getElements()[0];
        $this->assertSame(
            ['Creation', 'Noah'],
            $this->nodeNames($genesisNode->getChildren()),
        );
        $this->assertSame(
            ['Chapter 1'],
            $this->nodeNames(
                $genesisNode->getChildren()[0]->getChildren(),
            ),
        );
    }

    public function test_it_returns_an_empty_layout(): void
    {
        $creator = new User(
            id: 7,
            email: new EmailAddress('creator@example.com'),
            passwordHash: 'hashed-password',
        );
        $setRepository = new FakeSetRepository;
        $setLevelRepository = new FakeSetLevelRepository;
        $set = $setRepository->create(new CreateSetDto(
            name: 'Empty set',
            creator: $creator,
        ));
        $setLevelRepository->create(new CreateSetLevelDto(
            set: $set,
            kind: 'task',
        ));

        $layout = (new GetSetLayout(
            $setRepository,
            $setLevelRepository,
            new FakeElementRepository,
        ))->execute(new GetSetLayoutRequest(
            setId: $set->getId(),
        ));

        $this->assertSame([], $layout->getElements());
        $this->assertSame(0, $layout->getLevels()[0]->getElementCount());
    }

    public function test_it_rejects_an_unknown_set(): void
    {
        $this->expectException(NotFoundException::class);
        $this->expectExceptionMessage('set not found');

        (new GetSetLayout(
            new FakeSetRepository,
            new FakeSetLevelRepository,
            new FakeElementRepository,
        ))->execute(new GetSetLayoutRequest(
            setId: 999,
        ));
    }

    /**
     * @param list<ElementLayoutNode> $nodes
     * @return list<string>
     */
    private function nodeNames(array $nodes): array
    {
        return array_map(function ($node): string {
            return $node->getElement()->getName();
        }, $nodes);
    }
}