<?php

declare(strict_types=1);

namespace LIT\MCP\Tests\Unit\Integrations\SuperCache;

use Brain\Monkey\Functions;
use LIT\MCP\Integrations\SuperCache\SuperCacheFeature;
use LIT\MCP\Integrations\SuperCache\SuperCachePurger;
use LIT\MCP\Tests\Unit\TestCase;

final class SuperCachePurgerTest extends TestCase
{
    public function testALockedWholePurgeDoesNothingAndSaysSo(): void
    {
        $previous = ini_set('error_log', '/dev/null');
        Functions\expect('get_transient')->never();
        $purger = new SuperCachePurger(
            static fn (SuperCacheFeature $feature): bool => false,
            static fn (): bool => true,
            static fn (int $id) => self::fail('no post purge'),
            static fn (int $blog) => self::fail('no whole purge')
        );

        self::assertSame(SuperCachePurger::LOCKED, $purger->everything());
        self::assertFalse($purger->post(3));
        ini_set('error_log', (string) $previous);
    }

    public function testThrottledReadsTheStamp(): void
    {
        $stamp = false;
        Functions\when('get_transient')->alias(static function () use (&$stamp) {
            return $stamp;
        });
        $purger = new SuperCachePurger(static fn (): bool => true);

        self::assertFalse($purger->throttled());
        $stamp = (string) (time() - 5);
        self::assertTrue($purger->throttled());
        $stamp = time() - 31;
        self::assertFalse($purger->throttled());
    }

    /** The stamp is read once: a transient expiring between two reads must not schedule the trailing purge in 1970. */
    public function testEverythingReadsTheStampOnceAndSchedulesTheTrailingPurgeInTheFuture(): void
    {
        $reads = 0;
        $scheduledAt = [];
        Functions\when('get_transient')->alias(static function () use (&$reads) {
            return ++$reads === 1 ? time() - 5 : false;
        });
        Functions\when('wp_next_scheduled')->justReturn(false);
        Functions\when('wp_schedule_single_event')->alias(static function (int $at) use (&$scheduledAt): bool {
            $scheduledAt[] = $at;

            return true;
        });
        $purger = new SuperCachePurger(static fn (): bool => true);

        self::assertSame(SuperCachePurger::THROTTLED, $purger->everything());

        self::assertSame(1, $reads);
        self::assertCount(1, $scheduledAt);
        self::assertGreaterThanOrEqual(time(), $scheduledAt[0]);
    }
}