<?php
declare(strict_types=1);

namespace Unsupervised\Schedular\Tests\Unit\Availability;

use Unsupervised\Schedular\Availability\AvailabilitySlot;
use Unsupervised\Schedular\Availability\WeekCalendar;
use Unsupervised\Schedular\Tests\Unit\TestCase;

class WeekCalendarTest extends TestCase
{
    public function testWeekStartShiftsBackToConfiguredStartOfWeek(): void
    {
        // 2026-07-08 is a Wednesday; with Monday (1) starts, the week begins Jul 6.
        self::assertSame('2026-07-06', WeekCalendar::weekStart('2026-07-08', 1, '2026-01-01'));

        // With Sunday (0) starts, the same Wednesday's week begins Jul 5.
        self::assertSame('2026-07-05', WeekCalendar::weekStart('2026-07-08', 0, '2026-01-01'));
    }

    public function testWeekStartIsIdempotentWhenAnchorIsAlreadyTheStart(): void
    {
        self::assertSame('2026-07-06', WeekCalendar::weekStart('2026-07-06', 1, '2026-01-01'));
    }

    public function testWeekStartFallsBackToTodayForInvalidInput(): void
    {
        // 2026-07-05 is a Sunday; with Monday starts, its week began Jun 29.
        self::assertSame('2026-06-29', WeekCalendar::weekStart('', 1, '2026-07-05'));
        self::assertSame('2026-06-29', WeekCalendar::weekStart('not-a-date', 1, '2026-07-05'));
        self::assertSame('2026-06-29', WeekCalendar::weekStart('2026-13-40', 1, '2026-07-05'));
    }

    public function testDaysReturnsSevenBucketsWithSlotsOnTheirDates(): void
    {
        $monday    = new AvailabilitySlot(5, '2026-07-06 09:00:00', '2026-07-06 10:00:00', 60, null, false, null, 1);
        $mondayTwo = new AvailabilitySlot(5, '2026-07-06 10:00:00', '2026-07-06 11:00:00', 60, null, false, null, 2);
        $thursday  = new AvailabilitySlot(5, '2026-07-09 14:00:00', '2026-07-09 15:00:00', 60, null, false, null, 3);
        $nextWeek  = new AvailabilitySlot(5, '2026-07-13 09:00:00', '2026-07-13 10:00:00', 60, null, false, null, 4);

        $days = WeekCalendar::days('2026-07-06', [$monday, $mondayTwo, $thursday, $nextWeek]);

        self::assertCount(7, $days);
        self::assertSame('2026-07-06', $days[0]['date']);
        self::assertSame('2026-07-12', $days[6]['date']);

        self::assertCount(2, $days[0]['slots']);
        self::assertSame(3, $days[3]['slots'][0]->id);
        self::assertSame([], $days[1]['slots']);

        // A slot outside the week is not bucketed anywhere.
        $ids = array_merge(...array_map(
            static fn (array $day): array => array_map(static fn (AvailabilitySlot $s): ?int => $s->id, $day['slots']),
            $days
        ));
        self::assertNotContains(4, $ids);
    }

    public function testDaysCrossesMonthBoundary(): void
    {
        $days = WeekCalendar::days('2026-06-29', []);

        self::assertSame('2026-06-29', $days[0]['date']);
        self::assertSame('2026-07-05', $days[6]['date']);
    }

    public function testBucketGroupsItemsByExtractedDay(): void
    {
        $items = [
            ['day' => '2026-07-06', 'label' => 'a'],
            ['day' => '2026-07-06', 'label' => 'b'],
            ['day' => '2026-07-09', 'label' => 'c'],
            ['day' => '2026-07-13', 'label' => 'outside'],
            ['day' => '', 'label' => 'dayless'],
        ];

        $days = WeekCalendar::bucket('2026-07-06', $items, static fn (array $i): string => $i['day']);

        self::assertCount(7, $days);
        self::assertSame('2026-07-06', $days[0]['date']);
        self::assertSame('2026-07-12', $days[6]['date']);

        self::assertSame(['a', 'b'], array_column($days[0]['items'], 'label'));
        self::assertSame(['c'], array_column($days[3]['items'], 'label'));
        self::assertSame([], $days[1]['items']);

        // Items outside the week (or with no day) are not bucketed anywhere.
        $labels = array_merge(...array_column($days, 'items'));
        self::assertNotContains('outside', array_column($labels, 'label'));
        self::assertNotContains('dayless', array_column($labels, 'label'));
    }
}