<?php

declare(strict_types=1);

namespace Tests\Unit\Shared\Time;

use Psr\Clock\ClockInterface;
use Shared\Time\Clock;
use Shared\Time\FrozenClock;
use Shared\Time\SystemClock;
use Shared\Time\SystemUtcClock;
use Shared\Time\Utc;

covers(
    SystemClock::class,
    SystemUtcClock::class,
    FrozenClock::class,
    Utc::class,
);

afterEach(function (): void {
    Utc::restore();
});

describe('PSR-20 UTC Clock Unit Tests', function (): void {
    it('implements Psr ClockInterface and Clock contract with configured timezone', function (): void {
        // GIVEN
        $parisClock = new SystemClock(new \DateTimeZone('Europe/Paris'));
        $utcClock   = new SystemUtcClock();

        // WHEN
        $parisNow = $parisClock->now();
        $utcNow   = $utcClock->now();

        // THEN
        expect($parisClock)->toBeInstanceOf(ClockInterface::class)
            ->and($parisClock)->toBeInstanceOf(Clock::class)
            ->and($parisNow->getTimezone()->getName())->toBe('Europe/Paris')
            ->and($parisClock->timezone()->getName())->toBe('Europe/Paris')
            ->and($utcNow->getTimezone()->getName())->toBe('UTC');
    });

    it('parses date strings and normalizes to UTC with SystemUtcClock', function (): void {
        // GIVEN
        $clock = new SystemUtcClock();

        // WHEN
        $utcTime    = $clock->parse('2026-08-21T15:00:00+02:00');
        $startOfDay = $clock->startOfDay('2026-08-21');
        $endOfDay   = $clock->endOfDay('2026-08-21');
        $isoString  = $clock->toIso8601($utcTime);

        // THEN
        expect($utcTime->getTimezone()->getName())->toBe('UTC')
            ->and($utcTime->format('Y-m-d H:i:s'))->toBe('2026-08-21 13:00:00')
            ->and($startOfDay->format('Y-m-d H:i:s'))->toBe('2026-08-21 00:00:00')
            ->and($endOfDay->format('Y-m-d H:i:s.u'))->toBe('2026-08-21 23:59:59.999999')
            ->and($isoString)->toBe('2026-08-21T13:00:00+00:00');
    });

    it('allows freezing and manipulating time with FrozenClock', function (): void {
        // GIVEN
        $fixedTime   = new \DateTimeImmutable('2026-08-21 10:00:00', new \DateTimeZone('UTC'));
        $frozenClock = new FrozenClock($fixedTime);

        // THEN
        expect($frozenClock->now()->format('Y-m-d H:i:s'))->toBe('2026-08-21 10:00:00');

        // WHEN
        $frozenClock->setTo('2026-12-31 23:59:59');

        // THEN
        expect($frozenClock->now()->format('Y-m-d H:i:s'))->toBe('2026-12-31 23:59:59')
            ->and($frozenClock->now()->getTimezone()->getName())->toBe('UTC');
    });

    it('provides centralized static access through Utc facade', function (): void {
        // GIVEN
        $frozen = Utc::freeze(new \DateTimeImmutable('2026-08-21 14:00:00', new \DateTimeZone('UTC')));

        // THEN
        expect(Utc::now()->format('Y-m-d H:i:s'))->toBe('2026-08-21 14:00:00')
            ->and(Utc::parse('2026-08-21 12:00:00')->format('Y-m-d H:i:s'))->toBe('2026-08-21 12:00:00')
            ->and(Utc::startOfDay('2026-08-21')->format('Y-m-d H:i:s'))->toBe('2026-08-21 00:00:00')
            ->and(Utc::endOfDay('2026-08-21')->format('Y-m-d H:i:s'))->toBe('2026-08-21 23:59:59')
            ->and(Utc::toRfc3339('2026-08-21 14:00:00'))->toBe('2026-08-21T14:00:00+00:00')
            ->and(Utc::toNullableRfc3339(null))->toBeNull()
            ->and(Utc::toNullableRfc3339('2026-08-21 14:00:00'))->toBe('2026-08-21T14:00:00+00:00');

        // WHEN
        Utc::restore();

        // THEN
        expect(Utc::getClock())->toBeInstanceOf(SystemUtcClock::class);
    });
});