<?php

declare(strict_types=1);

use App\Framework\Core\ValueObjects\Duration;
use App\Framework\DateTime\SystemClock;
use App\Framework\DDoS\DDoSConfig;
use App\Framework\DDoS\ValueObjects\ThreatLevel;

require_once __DIR__ . '/Helpers/TestHelpers.php';

beforeEach(function () {
    $this->clock = new SystemClock();

    // Create DDoS config for testing
    $this->config = new DDoSConfig(
        enabled: true,
        volumetricThreshold: 100.0, // Lower threshold for faster testing
        distributedThreshold: 0.8,
        analysisWindow: Duration::fromMinutes(5),
        trustedIps: ['127.0.0.1', '::1'],
        exemptPaths: ['/health', '/ping']
    );

    // Mock the engine (we'll need to set up proper DI for real tests)
    $this->engine = $this->createMockEngine();
});

describe('DDoS Protection Engine', function () {

    it('allows normal requests through', function () {
        $request = createTestRequest('192.168.1.100', 'GET', '/api/users');

        $assessment = $this->engine->assessRequest($request);

        expect($assessment->threatLevel)->toBe(ThreatLevel::LOW);
        expect($assessment->shouldBlock)->toBeFalse();
        expect($assessment->threatScore)->toBeLessThan(0.3);
    });

    it('detects high volume attacks from single IP', function () {
        $attackerIp = '10.0.0.1';
        $assessment = null;

        // Simulate rapid requests from same IP
        for ($i = 1; $i <= 20; $i++) {
            $request = createTestRequest($attackerIp, 'GET', "/page{$i}");
            $assessment = $this->engine->assessRequest($request);

            if ($assessment->shouldBlock) {
                break;
            }
        }

        expect($assessment->threatLevel)->toBeIn([ThreatLevel::HIGH, ThreatLevel::CRITICAL]);
        expect($assessment->shouldBlock)->toBeTrue();
        expect($assessment->threatScore)->toBeGreaterThan(0.7);
    });

    it('detects distributed attacks', function () {
        $attackIps = ['1.2.3.4', '5.6.7.8', '9.10.11.12', '13.14.15.16'];
        $assessments = [];

        foreach ($attackIps as $ip) {
            for ($i = 1; $i <= 15; $i++) {
                $request = createTestRequest($ip, 'POST', '/api/login');
                $assessments[] = $this->engine->assessRequest($request);
            }
        }

        // Should detect distributed pattern
        $lastAssessment = end($assessments);
        expect($lastAssessment->threatLevel)->toBeIn([ThreatLevel::MEDIUM, ThreatLevel::HIGH]);
        expect($lastAssessment->threatScore)->toBeGreaterThan(0.4);
    });

    it('blocks suspicious bot traffic', function () {
        $request = createTestRequest('192.168.1.200', 'GET', '/sensitive-data', [
            'User-Agent' => 'BadBot/1.0 (automated scraper)',
        ]);

        $assessment = $this->engine->assessRequest($request);

        expect($assessment->threatLevel)->toBeIn([ThreatLevel::MEDIUM, ThreatLevel::HIGH]);
        expect($assessment->threatScore)->toBeGreaterThan(0.5);
    });

    it('allows trusted IPs through', function () {
        $request = createTestRequest('127.0.0.1', 'GET', '/admin/sensitive');

        $assessment = $this->engine->assessRequest($request);

        expect($assessment->threatLevel)->toBe(ThreatLevel::LOW);
        expect($assessment->shouldBlock)->toBeFalse();
    });

    it('bypasses exempt paths', function () {
        $request = createTestRequest('10.0.0.1', 'GET', '/health');

        $assessment = $this->engine->assessRequest($request);

        expect($assessment->threatLevel)->toBe(ThreatLevel::LOW);
        expect($assessment->shouldBlock)->toBeFalse();
    });

    it('escalates threat level with repeated attacks', function () {
        $attackerIp = '192.168.1.50';
        $assessments = [];

        // First wave - should be low threat
        for ($i = 1; $i <= 5; $i++) {
            $request = createTestRequest($attackerIp, 'GET', "/api/data{$i}");
            $assessments[] = $this->engine->assessRequest($request);
        }

        expect($assessments[0]->threatLevel)->toBe(ThreatLevel::LOW);

        // Second wave - should escalate
        for ($i = 6; $i <= 25; $i++) {
            $request = createTestRequest($attackerIp, 'GET', "/api/data{$i}");
            $assessments[] = $this->engine->assessRequest($request);
        }

        $lastAssessment = end($assessments);
        expect($lastAssessment->threatLevel)->toBeIn([ThreatLevel::MEDIUM, ThreatLevel::HIGH, ThreatLevel::CRITICAL]);
        expect($lastAssessment->threatScore)->toBeGreaterThan($assessments[0]->threatScore);
    });

    it('handles malformed requests gracefully', function () {
        $request = createTestRequest('invalid-ip', 'INVALID_METHOD', '');

        $assessment = $this->engine->assessRequest($request);

        // Should not crash and should treat as suspicious
        expect($assessment)->not()->toBeNull();
        expect($assessment->threatLevel)->toBeIn([ThreatLevel::MEDIUM, ThreatLevel::HIGH]);
    });

    it('provides detailed assessment information', function () {
        $request = createTestRequest('192.168.1.100', 'GET', '/api/test');

        $assessment = $this->engine->assessRequest($request);

        expect($assessment)->toHaveProperties([
            'threatLevel',
            'threatScore',
            'shouldBlock',
            'detectedPatterns',
            'responseRecommendation',
        ]);

        expect($assessment->threatScore)->toBeBetween(0.0, 1.0);
    });

});

describe('DDoS Configuration', function () {

    it('respects custom thresholds', function () {
        $strictConfig = new DDoSConfig(
            volumetricThreshold: 10.0, // Very low threshold
            highThreatThreshold: 0.3   // Lower threshold for high threat
        );

        $engine = createEngineWithConfig($strictConfig);
        $request = createTestRequest('192.168.1.100', 'GET', '/api/test');

        // With strict config, even normal requests might be flagged
        $assessment = $engine->assessRequest($request);
        expect($assessment)->not()->toBeNull();
    });

    it('can be disabled', function () {
        $disabledConfig = new DDoSConfig(enabled: false);
        $engine = createEngineWithConfig($disabledConfig);

        $request = createTestRequest('10.0.0.1', 'GET', '/api/test');
        $assessment = $engine->assessRequest($request);

        expect($assessment->threatLevel)->toBe(ThreatLevel::LOW);
        expect($assessment->shouldBlock)->toBeFalse();
    });

});

describe('Performance', function () {

    it('completes assessment within reasonable time', function () {
        $start = microtime(true);

        $request = createTestRequest('192.168.1.100', 'GET', '/api/test');
        $assessment = $this->engine->assessRequest($request);

        $duration = microtime(true) - $start;

        expect($duration)->toBeLessThan(0.1); // Should complete within 100ms
        expect($assessment)->not()->toBeNull();
    });

    it('handles high request volume efficiently', function () {
        $start = microtime(true);

        // Process 100 requests
        for ($i = 1; $i <= 100; $i++) {
            $ip = '192.168.1.' . ($i % 254 + 1);
            $request = createTestRequest($ip, 'GET', "/api/test{$i}");
            $this->engine->assessRequest($request);
        }

        $duration = microtime(true) - $start;
        $avgPerRequest = $duration / 100;

        expect($avgPerRequest)->toBeLessThan(0.01); // Average <10ms per request
    });

});

// Helper functions are now in Helpers/TestHelpers.php