<?php

namespace Tests\Unit\Schedule\UseCases;

use App\Element\CreateElementDto;
use App\Exceptions\BadRequestException;
use App\Exceptions\NotFoundException;
use App\Schedule\UseCases\CreateSchedule\CreateSchedule;
use App\Schedule\UseCases\CreateSchedule\CreateScheduleRequest;
use App\Set\CreateSetDto;
use App\Shared\ValueObject\EmailAddress;
use App\User\User;
use PHPUnit\Framework\TestCase;
use Tests\Fakes\FakeElementRepository;
use Tests\Fakes\FakeScheduleRepository;
use Tests\Fakes\FakeSetRepository;

class CreateScheduleTest extends TestCase
{
    public function test_it_schedules_every_matching_element_in_tree_order(): void
    {
        $user = $this->user();
        $setRepository = new FakeSetRepository;
        $elementRepository = new FakeElementRepository;
        $scheduleRepository = new FakeScheduleRepository;
        $set = $setRepository->create(new CreateSetDto(
            name: 'Bible',
            creator: $user,
        ));
        $genesis = $elementRepository->create(new CreateElementDto(
            set: $set,
            name: 'Genesis',
            kind: 'book',
            parentElement: null,
        ));
        $exodus = $elementRepository->create(new CreateElementDto(
            set: $set,
            name: 'Exodus',
            kind: 'book',
            parentElement: null,
        ));
        $exodusChapterOne = $elementRepository->create(
            new CreateElementDto(
                set: $set,
                name: 'Exodus 1',
                kind: 'chapter',
                parentElement: $exodus,
            ),
        );
        $creation = $elementRepository->create(new CreateElementDto(
            set: $set,
            name: 'Creation',
            kind: 'portion',
            parentElement: $genesis,
        ));
        $genesisChapterOne = $elementRepository->create(
            new CreateElementDto(
                set: $set,
                name: 'Genesis 1',
                kind: 'chapter',
                parentElement: $creation,
            ),
        );
        $genesisChapterTwo = $elementRepository->create(
            new CreateElementDto(
                set: $set,
                name: 'Genesis 2',
                kind: 'chapter',
                parentElement: $creation,
            ),
        );
        $genesisChapterThree = $elementRepository->create(
            new CreateElementDto(
                set: $set,
                name: 'Genesis 3',
                kind: 'chapter',
                parentElement: $creation,
            ),
        );
        $exodusChapterTwo = $elementRepository->create(
            new CreateElementDto(
                set: $set,
                name: 'Exodus 2',
                kind: 'chapter',
                parentElement: $exodus,
            ),
        );

        $schedule = (new CreateSchedule(
            $setRepository,
            $elementRepository,
            $scheduleRepository,
        ))->execute(new CreateScheduleRequest(
            user: $user,
            setId: $set->getId(),
            elementKind: 'chapter',
            startDate: '2026-08-10',
            targetDate: '2026-08-12',
        ));

        $this->assertSame('chapter', $schedule->getElementKind());
        $this->assertSame('2026-08-10', $schedule->getStartDate()->format(
            'Y-m-d',
        ));
        $this->assertSame('2026-08-12', $schedule->getTargetDate()->format(
            'Y-m-d',
        ));
        $this->assertSame(
            [
                $genesisChapterOne->getId(),
                $genesisChapterTwo->getId(),
                $genesisChapterThree->getId(),
                $exodusChapterOne->getId(),
                $exodusChapterTwo->getId(),
            ],
            array_map(function ($assignment): int {
                return $assignment->getElement()->getId();
            }, $schedule->getAssignments()),
        );
        $this->assertSame(
            [
                '2026-08-10',
                '2026-08-10',
                '2026-08-11',
                '2026-08-11',
                '2026-08-12',
            ],
            array_map(function ($assignment): string {
                return $assignment->getScheduledDate()->format('Y-m-d');
            }, $schedule->getAssignments()),
        );
    }

    public function test_it_spreads_sparse_work_across_the_full_range(): void
    {
        $user = $this->user();
        $setRepository = new FakeSetRepository;
        $elementRepository = new FakeElementRepository;
        $set = $setRepository->create(new CreateSetDto(
            name: 'Course',
            creator: $user,
        ));

        foreach (['First', 'Second', 'Third'] as $name) {
            $elementRepository->create(new CreateElementDto(
                set: $set,
                name: $name,
                kind: 'lesson',
                parentElement: null,
            ));
        }

        $schedule = (new CreateSchedule(
            $setRepository,
            $elementRepository,
            new FakeScheduleRepository,
        ))->execute(new CreateScheduleRequest(
            user: $user,
            setId: $set->getId(),
            elementKind: 'lesson',
            startDate: '2026-08-10',
            targetDate: '2026-08-16',
        ));

        $this->assertSame(
            ['2026-08-10', '2026-08-13', '2026-08-16'],
            array_map(function ($assignment): string {
                return $assignment->getScheduledDate()->format('Y-m-d');
            }, $schedule->getAssignments()),
        );
    }

    public function test_it_places_one_element_on_the_start_date(): void
    {
        $user = $this->user();
        $setRepository = new FakeSetRepository;
        $elementRepository = new FakeElementRepository;
        $set = $setRepository->create(new CreateSetDto(
            name: 'Project',
            creator: $user,
        ));
        $elementRepository->create(new CreateElementDto(
            set: $set,
            name: 'Ship it',
            kind: 'milestone',
            parentElement: null,
        ));

        $schedule = (new CreateSchedule(
            $setRepository,
            $elementRepository,
            new FakeScheduleRepository,
        ))->execute(new CreateScheduleRequest(
            user: $user,
            setId: $set->getId(),
            elementKind: 'milestone',
            startDate: '2020-01-01',
            targetDate: '2030-01-01',
        ));

        $this->assertSame(
            '2020-01-01',
            $schedule->getAssignments()[0]
                ->getScheduledDate()
                ->format('Y-m-d'),
        );
    }

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

        (new CreateSchedule(
            new FakeSetRepository,
            new FakeElementRepository,
            new FakeScheduleRepository,
        ))->execute(new CreateScheduleRequest(
            user: $this->user(),
            setId: 999,
            elementKind: 'chapter',
            startDate: '2026-08-10',
            targetDate: '2026-08-12',
        ));
    }

    public function test_it_rejects_an_unavailable_element_kind(): void
    {
        $user = $this->user();
        $setRepository = new FakeSetRepository;
        $set = $setRepository->create(new CreateSetDto(
            name: 'Bible',
            creator: $user,
        ));

        $this->expectException(BadRequestException::class);
        $this->expectExceptionMessage(
            'elementKind is not available for set',
        );

        (new CreateSchedule(
            $setRepository,
            new FakeElementRepository,
            new FakeScheduleRepository,
        ))->execute(new CreateScheduleRequest(
            user: $user,
            setId: $set->getId(),
            elementKind: 'Chapter',
            startDate: '2026-08-10',
            targetDate: '2026-08-12',
        ));
    }

    public function test_it_rejects_invalid_dates(): void
    {
        $user = $this->user();
        $setRepository = new FakeSetRepository;
        $set = $setRepository->create(new CreateSetDto(
            name: 'Bible',
            creator: $user,
        ));

        $this->expectException(BadRequestException::class);
        $this->expectExceptionMessage('startDate must be a valid date');

        (new CreateSchedule(
            $setRepository,
            new FakeElementRepository,
            new FakeScheduleRepository,
        ))->execute(new CreateScheduleRequest(
            user: $user,
            setId: $set->getId(),
            elementKind: 'chapter',
            startDate: '2026-02-30',
            targetDate: '2026-08-12',
        ));
    }

    public function test_it_rejects_a_target_before_the_start(): void
    {
        $user = $this->user();
        $setRepository = new FakeSetRepository;
        $set = $setRepository->create(new CreateSetDto(
            name: 'Bible',
            creator: $user,
        ));

        $this->expectException(BadRequestException::class);
        $this->expectExceptionMessage(
            'targetDate must not be before startDate',
        );

        (new CreateSchedule(
            $setRepository,
            new FakeElementRepository,
            new FakeScheduleRepository,
        ))->execute(new CreateScheduleRequest(
            user: $user,
            setId: $set->getId(),
            elementKind: 'chapter',
            startDate: '2026-08-12',
            targetDate: '2026-08-10',
        ));
    }

    private function user(): User
    {
        return new User(
            id: 7,
            email: new EmailAddress('reader@example.com'),
            passwordHash: 'hashed-password',
        );
    }
}