<?php

declare(strict_types=1);

namespace App\Tests\Unit\Auth;

use App\Auth\LoginThrottle;
use Monolog\Handler\NullHandler;
use Monolog\Logger;
use PHPUnit\Framework\TestCase;
use Psr\Log\LoggerInterface;

/**
 * Brute-force lockout progression: 5/10/15 attempts trigger 60/300/1800-second
 * locks. The (username, ip) tuple gates the bucket so the legit admin from
 * another IP isn't locked out by an attacker spraying one address.
 */
final class LoginThrottleTest extends TestCase
{
    public function testFastRetryUnderFive(): void
    {
        $t = $this->throttle();
        for ($i = 0; $i < 4; ++$i) {
            $t->recordFailure('admin', '10.0.0.1');
        }
        self::assertFalse($t->isLocked('admin', '10.0.0.1'));
    }

    public function testFifthFailureLocksForOneMinute(): void
    {
        $t = $this->throttle();
        for ($i = 0; $i < 5; ++$i) {
            $t->recordFailure('admin', '10.0.0.1');
        }
        self::assertTrue($t->isLocked('admin', '10.0.0.1'));
        self::assertGreaterThanOrEqual(60, $t->lockoutSecondsRemaining('admin', '10.0.0.1'));
        self::assertLessThanOrEqual(60, $t->lockoutSecondsRemaining('admin', '10.0.0.1'));
    }

    public function testTenthFailureLocksForFiveMinutes(): void
    {
        $now = 1000000;
        $t = $this->throttle($now);
        for ($i = 0; $i < 10; ++$i) {
            $t->recordFailure('admin', '10.0.0.1');
        }
        self::assertSame(300, $t->lockoutSecondsRemaining('admin', '10.0.0.1'));
    }

    public function testFifteenthFailureLocksForThirtyMinutes(): void
    {
        $now = 1000000;
        $t = $this->throttle($now);
        for ($i = 0; $i < 15; ++$i) {
            $t->recordFailure('admin', '10.0.0.1');
        }
        self::assertSame(1800, $t->lockoutSecondsRemaining('admin', '10.0.0.1'));
    }

    public function testLockoutExpiresAfterTimeAdvance(): void
    {
        $now = 1000000;
        $t = new LoginThrottle($this->logger(), function () use (&$now): int {
            return $now;
        });
        for ($i = 0; $i < 5; ++$i) {
            $t->recordFailure('admin', '10.0.0.1');
        }
        self::assertTrue($t->isLocked('admin', '10.0.0.1'));
        $now += 61;
        self::assertFalse($t->isLocked('admin', '10.0.0.1'));
    }

    public function testDifferentIpHasIndependentBucket(): void
    {
        $t = $this->throttle();
        for ($i = 0; $i < 5; ++$i) {
            $t->recordFailure('admin', '10.0.0.1');
        }
        self::assertTrue($t->isLocked('admin', '10.0.0.1'));
        self::assertFalse($t->isLocked('admin', '10.0.0.2'));
    }

    public function testClearResetsBucket(): void
    {
        $t = $this->throttle();
        for ($i = 0; $i < 5; ++$i) {
            $t->recordFailure('admin', '10.0.0.1');
        }
        $t->clear('admin', '10.0.0.1');
        self::assertFalse($t->isLocked('admin', '10.0.0.1'));
        self::assertSame(0, $t->lockoutSecondsRemaining('admin', '10.0.0.1'));
    }

    public function testUsernameCaseDoesNotMultiplyBuckets(): void
    {
        $t = $this->throttle();
        for ($i = 0; $i < 3; ++$i) {
            $t->recordFailure('admin', '10.0.0.1');
        }
        for ($i = 0; $i < 2; ++$i) {
            $t->recordFailure('ADMIN', '10.0.0.1');
        }
        self::assertTrue($t->isLocked('Admin', '10.0.0.1'));
    }

    private function throttle(?int $fixedTime = null): LoginThrottle
    {
        if ($fixedTime === null) {
            return new LoginThrottle($this->logger());
        }

        return new LoginThrottle($this->logger(), static fn (): int => $fixedTime);
    }

    private function logger(): LoggerInterface
    {
        $l = new Logger('test');
        $l->pushHandler(new NullHandler());

        return $l;
    }
}