┌─────────────────────────────────────────────────────────────┐
│                 Encryption Layers                           │
├─────────────────┬─────────────────┬─────────────────────────┤
│ Transport Layer │ Application     │ Media Stream            │
│ (TLS 1.3)       │ Layer (AES-256) │ (SRTP/SRTCP)           │
├─────────────────┼─────────────────┼─────────────────────────┤
│ • WebSocket WSS │ • Signaling     │ • Audio/Video Streams   │
│ • HTTPS API     │ • Chat Messages │ • Screen Share          │
│ • Database      │ • File Transfer │ • Recording             │
└─────────────────┴─────────────────┴─────────────────────────┘

class MediaEncryptionManager {
    constructor() {
        this.dtlsFingerprints = new Map();
        this.srtpKeys = new Map();
    }
    
    async setupSecureMediaChannel(participantA, participantB) {
        // Generate DTLS certificates for each participant
        const certA = await this.generateDTLSCertificate(participantA.id);
        const certB = await this.generateDTLSCertificate(participantB.id);
        
        // Exchange fingerprints via signaling
        await this.exchangeFingerprints(participantA, participantB, certA, certB);
        
        // Establish DTLS handshake
        const dtlsSession = await this.performDTLSHandshake(participantA, participantB);
        
        // Derive SRTP keys from DTLS session
        const srtpKeys = this.deriveSRTPKeys(dtlsSession);
        
        // Configure SRTP encryption
        return this.configureSRTPEncryption(srtpKeys);
    }
    
    generateDTLSCertificate(participantId) {
        return crypto.subtle.generateKey(
            {
                name: 'ECDSA',
                namedCurve: 'P-256'
            },
            true,
            ['sign', 'verify']
        );
    }
    
    configureSRTPEncryption(keys) {
        return {
            cipherSuite: 'AES_CM_128_HMAC_SHA1_80',
            masterKey: keys.masterKey,
            masterSalt: keys.masterSalt,
            keyDerivationRate: 0, // No key derivation
            authTagLength: 80     // 80-bit authentication tag
        };
    }
}

class ChatEncryptionManager {
    constructor() {
        this.keyPairs = new Map(); // Per-user key pairs
        this.roomKeys = new Map();  // Per-meeting symmetric keys
    }
    
    async initializeUserEncryption(userId) {
        // Generate RSA key pair for user
        const keyPair = await crypto.subtle.generateKey(
            {
                name: 'RSA-OAEP',
                modulusLength: 2048,
                publicExponent: new Uint8Array([1, 0, 1]),
                hash: 'SHA-256'
            },
            true,
            ['encrypt', 'decrypt']
        );
        
        this.keyPairs.set(userId, keyPair);
        
        // Store public key on server, keep private key on client
        await this.storePublicKey(userId, keyPair.publicKey);
        
        return keyPair;
    }
    
    async encryptChatMessage(meetingId, senderId, message) {
        // Get or create room key
        let roomKey = this.roomKeys.get(meetingId);
        if (!roomKey) {
            roomKey = await this.generateRoomKey();
            this.roomKeys.set(meetingId, roomKey);
        }
        
        // Encrypt message with room key (AES-GCM)
        const encryptedMessage = await crypto.subtle.encrypt(
            {
                name: 'AES-GCM',
                iv: crypto.getRandomValues(new Uint8Array(12))
            },
            roomKey,
            new TextEncoder().encode(message)
        );
        
        // Encrypt room key for each participant
        const participants = await this.getMeetingParticipants(meetingId);
        const encryptedKeys = await this.encryptRoomKeyForParticipants(
            roomKey, 
            participants
        );
        
        return {
            encryptedMessage: Array.from(new Uint8Array(encryptedMessage)),
            encryptedKeys: encryptedKeys,
            senderId: senderId,
            timestamp: Date.now()
        };
    }
}

class MFAManager {
    constructor() {
        this.totpGenerator = new TOTPGenerator();
        this.smsProvider = new SMSProvider();
        this.emailProvider = new EmailProvider();
    }
    
    async setupMFA(userId, method) {
        switch (method) {
            case 'totp':
                return await this.setupTOTP(userId);
            case 'sms':
                return await this.setupSMS(userId);
            case 'email':
                return await this.setupEmail(userId);
            case 'hardware':
                return await this.setupHardwareKey(userId);
        }
    }
    
    async setupTOTP(userId) {
        // Generate secret key
        const secret = this.totpGenerator.generateSecret();
        
        // Create QR code for authenticator app
        const qrCode = this.totpGenerator.generateQRCode(
            secret,
            `VideoConf:${userId}`,
            'VideoConf Platform'
        );
        
        // Store encrypted secret
        await this.storeEncryptedSecret(userId, secret);
        
        return {
            secret: secret,
            qrCode: qrCode,
            backupCodes: this.generateBackupCodes(userId)
        };
    }
    
    async verifyMFA(userId, token, method) {
        switch (method) {
            case 'totp':
                return this.verifyTOTP(userId, token);
            case 'sms':
                return this.verifySMS(userId, token);
            case 'email':
                return this.verifyEmail(userId, token);
            case 'hardware':
                return this.verifyHardwareKey(userId, token);
        }
    }
}

class RBACManager {
    constructor() {
        this.roles = {
            'host': {
                permissions: [
                    'meeting.create', 'meeting.delete', 'meeting.modify',
                    'participant.admit', 'participant.remove', 'participant.mute',
                    'recording.start', 'recording.stop', 'recording.download',
                    'screen_share.control', 'breakout_rooms.create'
                ]
            },
            'co-host': {
                permissions: [
                    'participant.admit', 'participant.mute',
                    'recording.start', 'recording.stop',
                    'screen_share.control', 'breakout_rooms.manage'
                ]
            },
            'participant': {
                permissions: [
                    'audio.toggle', 'video.toggle', 'screen_share.start',
                    'chat.send', 'reactions.send', 'hand.raise'
                ]
            },
            'viewer': {
                permissions: [
                    'chat.send', 'reactions.send', 'hand.raise'
                ]
            }
        };
    }
    
    async checkPermission(userId, meetingId, action) {
        // Get user's role in the meeting
        const userRole = await this.getUserRole(userId, meetingId);
        
        // Check if role has permission
        const rolePermissions = this.roles[userRole]?.permissions || [];
        
        if (!rolePermissions.includes(action)) {
            throw new UnauthorizedError(`User ${userId} lacks permission: ${action}`);
        }
        
        // Additional context-based checks
        return await this.performContextualChecks(userId, meetingId, action);
    }
    
    async performContextualChecks(userId, meetingId, action) {
        const meetingState = await this.getMeetingState(meetingId);
        
        // Example: Can't start recording if meeting hasn't started
        if (action === 'recording.start' && meetingState.status !== 'active') {
            throw new ForbiddenError('Cannot start recording before meeting begins');
        }
        
        // Example: Can't admit participants if waiting room is disabled
        if (action === 'participant.admit' && !meetingState.waitingRoomEnabled) {
            throw new ForbiddenError('Waiting room is not enabled');
        }
        
        return true;
    }
}

class PrivacyManager {
    constructor() {
        this.retentionPolicies = {
            'meeting_metadata': '7-years',
            'chat_messages': '1-year',
            'recordings': '3-years',
            'analytics_data': '2-years',
            'session_logs': '90-days'
        };
        this.dataClassifications = {
            'PII': 'high-protection',
            'meeting_content': 'medium-protection',
            'usage_analytics': 'low-protection'
        };
    }
    
    async applyDataMinimization(dataType, data) {
        switch (dataType) {
            case 'meeting_participant':
                return this.minimizeParticipantData(data);
            case 'chat_message':
                return this.minimizeChatData(data);
            case 'recording_metadata':
                return this.minimizeRecordingData(data);
        }
    }
    
    minimizeParticipantData(participant) {
        // Only store essential data
        return {
            participant_id: participant.id,
            display_name: participant.displayName, // User-provided, not real name
            join_time: participant.joinTime,
            leave_time: participant.leaveTime,
            // Remove: IP address, user agent, device info
        };
    }
    
    async scheduleDataDeletion(dataType, dataId, createdAt) {
        const retentionPeriod = this.retentionPolicies[dataType];
        const deletionDate = this.calculateDeletionDate(createdAt, retentionPeriod);
        
        // Schedule automatic deletion
        await this.scheduleJob('data-deletion', {
            dataType: dataType,
            dataId: dataId,
            scheduledFor: deletionDate
        });
        
        return deletionDate;
    }
}

class ConsentManager {
    constructor() {
        this.consentTypes = {
            'video_processing': {
                required: true,
                description: 'Process video for meeting participation'
            },
            'audio_processing': {
                required: true,
                description: 'Process audio for meeting participation'
            },
            'recording_consent': {
                required: false,
                description: 'Allow meeting recording'
            },
            'analytics_tracking': {
                required: false,
                description: 'Collect usage analytics for service improvement'
            },
            'marketing_communications': {
                required: false,
                description: 'Receive product updates and marketing emails'
            }
        };
    }
    
    async requestConsent(userId, consentTypes) {
        const consentRequest = {
            userId: userId,
            requestId: this.generateRequestId(),
            consentTypes: consentTypes,
            requestedAt: new Date(),
            status: 'pending'
        };
        
        // Store consent request
        await this.storeConsentRequest(consentRequest);
        
        // Send consent form to user
        await this.sendConsentForm(userId, consentRequest);
        
        return consentRequest.requestId;
    }
    
    async recordConsent(userId, consentResponses) {
        const consentRecord = {
            userId: userId,
            consents: consentResponses,
            recordedAt: new Date(),
            ipAddress: this.hashIP(this.getCurrentIP()), // Hash for privacy
            userAgent: this.sanitizeUserAgent(this.getCurrentUserAgent())
        };
        
        // Store consent record with digital signature
        await this.storeConsentRecord(consentRecord);
        
        // Update user permissions based on consent
        await this.updateUserPermissions(userId, consentResponses);
        
        return consentRecord;
    }
}

class SecurityMonitor {
    constructor() {
        this.anomalyDetector = new AnomalyDetector();
        this.threatIntelligence = new ThreatIntelligenceService();
        this.incidentResponse = new IncidentResponseSystem();
    }
    
    async monitorMeetingSecurity(meetingId) {
        const securityMetrics = {
            // Connection anomalies
            connectionPatterns: await this.analyzeConnectionPatterns(meetingId),
            
            // Authentication failures
            authFailures: await this.trackAuthenticationFailures(meetingId),
            
            // Unusual participant behavior
            participantBehavior: await this.analyzeParticipantBehavior(meetingId),
            
            // Network security
            networkSecurity: await this.assessNetworkSecurity(meetingId)
        };
        
        // Check for security threats
        const threats = await this.detectThreats(securityMetrics);
        
        if (threats.length > 0) {
            await this.handleSecurityThreats(meetingId, threats);
        }
        
        return securityMetrics;
    }
    
    async detectThreats(metrics) {
        const threats = [];
        
        // Detect brute force attacks
        if (metrics.authFailures.rate > 10) { // 10 failures per minute
            threats.push({
                type: 'brute_force_attack',
                severity: 'high',
                source: metrics.authFailures.sourceIPs
            });
        }
        
        // Detect meeting bombing attempts
        if (metrics.connectionPatterns.rapidJoins > 50) { // 50 joins in 1 minute
            threats.push({
                type: 'meeting_bombing',
                severity: 'critical',
                participantCount: metrics.connectionPatterns.rapidJoins
            });
        }
        
        // Detect suspicious geographic patterns
        const geoAnomaly = await this.anomalyDetector.detectGeographicAnomalies(
            metrics.connectionPatterns.locations
        );
        if (geoAnomaly.score > 0.8) {
            threats.push({
                type: 'geographic_anomaly',
                severity: 'medium',
                anomalyScore: geoAnomaly.score
            });
        }
        
        return threats;
    }
}

class IncidentResponseSystem {
    constructor() {
        this.responsePlaybooks = {
            'meeting_bombing': this.meetingBombingPlaybook,
            'brute_force_attack': this.bruteForcePlaybook,
            'data_breach': this.dataBreachPlaybook,
            'service_disruption': this.serviceDisruptionPlaybook
        };
    }
    
    async handleIncident(incidentType, incidentData) {
        const incident = {
            id: this.generateIncidentId(),
            type: incidentType,
            severity: this.calculateSeverity(incidentType, incidentData),
            data: incidentData,
            createdAt: new Date(),
            status: 'active'
        };
        
        // Log incident
        await this.logIncident(incident);
        
        // Execute response playbook
        const playbook = this.responsePlaybooks[incidentType];
        if (playbook) {
            await playbook.execute(incident);
        }
        
        // Notify security team
        await this.notifySecurityTeam(incident);
        
        return incident;
    }
    
    meetingBombingPlaybook = {
        async execute(incident) {
            const meetingId = incident.data.meetingId;
            
            // Immediate response
            await this.enableWaitingRoom(meetingId);
            await this.requireAuthentication(meetingId);
            await this.limitParticipants(meetingId, 100);
            
            // Block suspicious IPs
            const suspiciousIPs = incident.data.sourceIPs;
            await this.blockIPAddresses(suspiciousIPs, '1-hour');
            
            // Notify meeting host
            await this.notifyMeetingHost(meetingId, {
                type: 'security_alert',
                message: 'Meeting bombing attempt detected. Security measures activated.'
            });
            
            // Enhanced monitoring
            await this.enableEnhancedMonitoring(meetingId, '2-hours');
        }
    };
}

class AuditLogger {
    constructor() {
        this.auditEvents = {
            'user_login': { retention: '7-years', pii: true },
            'meeting_created': { retention: '7-years', pii: false },
            'participant_joined': { retention: '3-years', pii: true },
            'recording_started': { retention: '7-years', pii: false },
            'data_exported': { retention: '10-years', pii: true },
            'permission_changed': { retention: '7-years', pii: true }
        };
    }
    
    async logEvent(eventType, userId, details) {
        const auditEvent = {
            eventId: this.generateEventId(),
            eventType: eventType,
            userId: userId,
            timestamp: new Date(),
            details: this.sanitizeDetails(details),
            ipAddress: this.hashIP(this.getCurrentIP()),
            userAgent: this.sanitizeUserAgent(this.getCurrentUserAgent()),
            sessionId: this.getCurrentSessionId()
        };
        
        // Add digital signature for tamper detection
        auditEvent.signature = await this.signEvent(auditEvent);
        
        // Store in immutable audit log
        await this.storeAuditEvent(auditEvent);
        
        // Real-time compliance monitoring
        await this.checkComplianceRules(auditEvent);
        
        return auditEvent.eventId;
    }
    
    async generateComplianceReport(startDate, endDate, complianceFramework) {
        const auditEvents = await this.getAuditEvents(startDate, endDate);
        
        switch (complianceFramework) {
            case 'GDPR':
                return this.generateGDPRReport(auditEvents);
            case 'HIPAA':
                return this.generateHIPAAReport(auditEvents);
            case 'SOC2':
                return this.generateSOC2Report(auditEvents);
            case 'ISO27001':
                return this.generateISO27001Report(auditEvents);
        }
    }
    
    generateGDPRReport(auditEvents) {
        return {
            dataProcessingActivities: this.analyzeDataProcessing(auditEvents),
            consentManagement: this.analyzeConsentEvents(auditEvents),
            dataSubjectRights: this.analyzeDataSubjectRequests(auditEvents),
            dataBreaches: this.identifyPotentialBreaches(auditEvents),
            crossBorderTransfers: this.analyzeCrossBorderTransfers(auditEvents)
        };
    }
}

class DLPManager {
    constructor() {
        this.sensitiveDataPatterns = {
            'ssn': /\b\d{3}-\d{2}-\d{4}\b/g,
            'credit_card': /\b\d{4}[\s-]?\d{4}[\s-]?\d{4}[\s-]?\d{4}\b/g,
            'email': /\b[A-Za-z0-9._%+-]+@[A-Za-z0-9.-]+\.[A-Z|a-z]{2,}\b/g,
            'phone': /\b\d{3}[-.]?\d{3}[-.]?\d{4}\b/g,
            'medical_record': /\bMRN[\s:]?\d{6,10}\b/gi
        };
        this.mlClassifier = new SensitiveDataClassifier();
    }
    
    async scanChatMessage(message, meetingContext) {
        const scanResults = {
            containsSensitiveData: false,
            detectedPatterns: [],
            riskScore: 0,
            action: 'allow'
        };
        
        // Pattern-based detection
        for (const [type, pattern] of Object.entries(this.sensitiveDataPatterns)) {
            const matches = message.match(pattern);
            if (matches) {
                scanResults.detectedPatterns.push({
                    type: type,
                    matches: matches.length,
                    confidence: 0.9
                });
            }
        }
        
        // ML-based classification
        const mlResults = await this.mlClassifier.classify(message);
        if (mlResults.confidence > 0.7) {
            scanResults.detectedPatterns.push({
                type: mlResults.category,
                confidence: mlResults.confidence
            });
        }
        
        // Calculate risk score
        scanResults.riskScore = this.calculateRiskScore(
            scanResults.detectedPatterns,
            meetingContext
        );
        
        // Determine action
        scanResults.action = this.determineAction(scanResults.riskScore, meetingContext);
        
        return scanResults;
    }
    
    determineAction(riskScore, context) {
        if (riskScore > 0.8) {
            return 'block'; // Block message completely
        } else if (riskScore > 0.6) {
            return 'redact'; // Redact sensitive parts
        } else if (riskScore > 0.4) {
            return 'warn'; // Warn user before sending
        } else {
            return 'allow'; // Allow message
        }
    }
}