import { EventEmitter } from 'events';
import { createHash, randomBytes } from 'crypto';

/**
 * Enterprise Manager for ZAI Platform
 * Handles enterprise features, custom integrations, and white-label solutions
 */
export class EnterpriseManager extends EventEmitter {
  constructor() {
    super();
    
    this.enterprises = new Map();
    this.customIntegrations = new Map();
    this.whiteLabels = new Map();
    this.supportTickets = new Map();
    this.dedicatedSupport = new Map();
    
    // Enterprise feature configurations
    this.enterpriseFeatures = {
      customBranding: true,
      dedicatedSupport: true,
      customIntegrations: true,
      advancedAnalytics: true,
      ssoIntegration: true,
      apiAccess: true,
      whiteLabeling: true,
      prioritySupport: true,
      customReporting: true,
      bulkLicenseManagement: true
    };
    
    console.log('🏢 Enterprise Manager initialized');
  }

  /**
   * Register enterprise customer
   */
  async registerEnterprise(enterpriseData) {
    const enterpriseId = this.generateEnterpriseId();
    
    const enterprise = {
      enterpriseId,
      companyName: enterpriseData.companyName,
      contactEmail: enterpriseData.contactEmail,
      contactName: enterpriseData.contactName,
      industry: enterpriseData.industry,
      employeeCount: enterpriseData.employeeCount,
      plan: enterpriseData.plan || 'ENTERPRISE',
      features: { ...this.enterpriseFeatures },
      customizations: {},
      integrations: [],
      supportLevel: 'DEDICATED',
      createdAt: new Date().toISOString(),
      status: 'ACTIVE',
      billing: {
        customPricing: true,
        billingCycle: 'ANNUAL',
        contractLength: 12
      },
      usage: {
        totalLicenses: 0,
        activeUsers: 0,
        apiCalls: 0,
        supportTickets: 0
      }
    };
    
    this.enterprises.set(enterpriseId, enterprise);
    
    // Setup dedicated support
    await this.setupDedicatedSupport(enterpriseId, enterprise);
    
    // Generate enterprise API keys
    const apiKeys = await this.generateEnterpriseAPIKeys(enterpriseId);
    enterprise.apiKeys = apiKeys;
    
    console.log(`🏢 Enterprise registered: ${enterpriseData.companyName} (${enterpriseId})`);
    this.emit('enterpriseRegistered', enterprise);
    
    return enterprise;
  }

  /**
   * Setup custom integration for enterprise
   */
  async setupCustomIntegration(enterpriseId, integrationConfig) {
    const integration = {
      integrationId: this.generateIntegrationId(),
      enterpriseId,
      type: integrationConfig.type, // 'webhook', 'api', 'sso', 'crm'
      name: integrationConfig.name,
      config: integrationConfig.config,
      endpoints: integrationConfig.endpoints || [],
      authentication: integrationConfig.authentication,
      status: 'PENDING',
      createdAt: new Date().toISOString(),
      testResults: null
    };
    
    // Validate integration configuration
    const validation = await this.validateIntegrationConfig(integration);
    if (!validation.valid) {
      throw new Error(`Integration validation failed: ${validation.errors.join(', ')}`);
    }
    
    // Test integration
    const testResult = await this.testIntegration(integration);
    integration.testResults = testResult;
    integration.status = testResult.success ? 'ACTIVE' : 'FAILED';
    
    this.customIntegrations.set(integration.integrationId, integration);
    
    // Update enterprise record
    const enterprise = this.enterprises.get(enterpriseId);
    if (enterprise) {
      enterprise.integrations.push(integration.integrationId);
    }
    
    console.log(`🔗 Custom integration setup: ${integration.name} for ${enterpriseId}`);
    this.emit('integrationSetup', integration);
    
    return integration;
  }

  /**
   * Setup white-label solution
   */
  async setupWhiteLabel(enterpriseId, whiteLabelConfig) {
    const whiteLabel = {
      whiteLabelId: this.generateWhiteLabelId(),
      enterpriseId,
      brandName: whiteLabelConfig.brandName,
      domain: whiteLabelConfig.domain,
      branding: {
        logo: whiteLabelConfig.branding.logo,
        colors: whiteLabelConfig.branding.colors,
        fonts: whiteLabelConfig.branding.fonts,
        customCSS: whiteLabelConfig.branding.customCSS
      },
      features: whiteLabelConfig.features || { ...this.enterpriseFeatures },
      customization: {
        welcomeMessage: whiteLabelConfig.customization.welcomeMessage,
        supportEmail: whiteLabelConfig.customization.supportEmail,
        termsOfService: whiteLabelConfig.customization.termsOfService,
        privacyPolicy: whiteLabelConfig.customization.privacyPolicy
      },
      deployment: {
        type: whiteLabelConfig.deployment.type, // 'subdomain', 'custom-domain', 'embedded'
        url: whiteLabelConfig.deployment.url,
        sslEnabled: true,
        status: 'PENDING'
      },
      createdAt: new Date().toISOString()
    };
    
    // Deploy white-label instance
    const deployment = await this.deployWhiteLabelInstance(whiteLabel);
    whiteLabel.deployment = { ...whiteLabel.deployment, ...deployment };
    
    this.whiteLabels.set(whiteLabel.whiteLabelId, whiteLabel);
    
    console.log(`🎨 White-label setup: ${whiteLabel.brandName} for ${enterpriseId}`);
    this.emit('whiteLabelSetup', whiteLabel);
    
    return whiteLabel;
  }

  /**
   * Setup dedicated support for enterprise
   */
  async setupDedicatedSupport(enterpriseId, enterprise) {
    const supportConfig = {
      enterpriseId,
      supportLevel: 'DEDICATED',
      responseTime: {
        critical: '1 hour',
        high: '4 hours',
        medium: '24 hours',
        low: '72 hours'
      },
      channels: ['email', 'phone', 'slack', 'teams'],
      dedicatedManager: {
        name: 'Enterprise Support Manager',
        email: 'enterprise-support@zai-platform.com',
        phone: '+1-800-ZAI-SUPPORT'
      },
      escalationPath: [
        'Level 1: Technical Support',
        'Level 2: Senior Engineer',
        'Level 3: Engineering Manager',
        'Level 4: CTO'
      ],
      businessHours: '24/7',
      timezone: enterprise.timezone || 'UTC'
    };
    
    this.dedicatedSupport.set(enterpriseId, supportConfig);
    
    console.log(`📞 Dedicated support setup for ${enterpriseId}`);
    return supportConfig;
  }

  /**
   * Generate enterprise API keys
   */
  async generateEnterpriseAPIKeys(enterpriseId) {
    const apiKeys = {
      production: {
        publicKey: `zai_prod_${randomBytes(16).toString('hex')}`,
        secretKey: `zai_secret_${randomBytes(32).toString('hex')}`,
        permissions: ['read', 'write', 'admin'],
        rateLimit: 10000 // requests per hour
      },
      sandbox: {
        publicKey: `zai_test_${randomBytes(16).toString('hex')}`,
        secretKey: `zai_secret_${randomBytes(32).toString('hex')}`,
        permissions: ['read', 'write'],
        rateLimit: 1000 // requests per hour
      }
    };
    
    console.log(`🔑 API keys generated for enterprise ${enterpriseId}`);
    return apiKeys;
  }

  /**
   * Create support ticket
   */
  async createSupportTicket(enterpriseId, ticketData) {
    const ticketId = this.generateTicketId();
    
    const ticket = {
      ticketId,
      enterpriseId,
      subject: ticketData.subject,
      description: ticketData.description,
      priority: ticketData.priority || 'MEDIUM',
      category: ticketData.category || 'GENERAL',
      status: 'OPEN',
      assignedTo: null,
      createdBy: ticketData.createdBy,
      createdAt: new Date().toISOString(),
      updatedAt: new Date().toISOString(),
      messages: [],
      attachments: ticketData.attachments || [],
      resolution: null,
      satisfactionRating: null
    };
    
    // Auto-assign based on category and priority
    ticket.assignedTo = await this.autoAssignTicket(ticket);
    
    this.supportTickets.set(ticketId, ticket);
    
    // Send notifications
    await this.sendTicketNotifications(ticket);
    
    console.log(`🎫 Support ticket created: ${ticketId} for ${enterpriseId}`);
    this.emit('supportTicketCreated', ticket);
    
    return ticket;
  }

  /**
   * Generate custom reports for enterprise
   */
  async generateCustomReport(enterpriseId, reportConfig) {
    const enterprise = this.enterprises.get(enterpriseId);
    if (!enterprise) {
      throw new Error('Enterprise not found');
    }
    
    const report = {
      reportId: this.generateReportId(),
      enterpriseId,
      type: reportConfig.type,
      dateRange: reportConfig.dateRange,
      metrics: reportConfig.metrics,
      generatedAt: new Date().toISOString(),
      data: {}
    };
    
    // Generate report data based on type
    switch (reportConfig.type) {
      case 'usage':
        report.data = await this.generateUsageReport(enterprise, reportConfig);
        break;
      case 'financial':
        report.data = await this.generateFinancialReport(enterprise, reportConfig);
        break;
      case 'performance':
        report.data = await this.generatePerformanceReport(enterprise, reportConfig);
        break;
      case 'security':
        report.data = await this.generateSecurityReport(enterprise, reportConfig);
        break;
    }
    
    console.log(`📊 Custom report generated: ${report.reportId} for ${enterpriseId}`);
    this.emit('customReportGenerated', report);
    
    return report;
  }

  /**
   * Bulk license management
   */
  async bulkLicenseOperation(enterpriseId, operation, licenseData) {
    const enterprise = this.enterprises.get(enterpriseId);
    if (!enterprise) {
      throw new Error('Enterprise not found');
    }
    
    const results = {
      operation,
      enterpriseId,
      totalRequested: licenseData.length,
      successful: 0,
      failed: 0,
      results: [],
      timestamp: new Date().toISOString()
    };
    
    for (const license of licenseData) {
      try {
        let result;
        
        switch (operation) {
          case 'CREATE':
            result = await this.createEnterpriseLicense(enterpriseId, license);
            break;
          case 'UPDATE':
            result = await this.updateEnterpriseLicense(enterpriseId, license);
            break;
          case 'DEACTIVATE':
            result = await this.deactivateEnterpriseLicense(enterpriseId, license);
            break;
          case 'TRANSFER':
            result = await this.transferEnterpriseLicense(enterpriseId, license);
            break;
        }
        
        results.results.push({ success: true, data: result });
        results.successful++;
        
      } catch (error) {
        results.results.push({ success: false, error: error.message });
        results.failed++;
      }
    }
    
    console.log(`📦 Bulk license operation completed: ${operation} for ${enterpriseId}`);
    this.emit('bulkLicenseOperation', results);
    
    return results;
  }

  /**
   * Utility methods
   */
  generateEnterpriseId() {
    return 'ENT-' + randomBytes(8).toString('hex').toUpperCase();
  }
  
  generateIntegrationId() {
    return 'INT-' + randomBytes(8).toString('hex').toUpperCase();
  }
  
  generateWhiteLabelId() {
    return 'WL-' + randomBytes(8).toString('hex').toUpperCase();
  }
  
  generateTicketId() {
    return 'TKT-' + Date.now() + '-' + randomBytes(4).toString('hex').toUpperCase();
  }
  
  generateReportId() {
    return 'RPT-' + Date.now() + '-' + randomBytes(4).toString('hex').toUpperCase();
  }

  /**
   * Get enterprise dashboard
   */
  getEnterpriseDashboard(enterpriseId) {
    const enterprise = this.enterprises.get(enterpriseId);
    if (!enterprise) {
      throw new Error('Enterprise not found');
    }
    
    const integrations = enterprise.integrations.map(id => 
      this.customIntegrations.get(id)
    ).filter(Boolean);
    
    const whiteLabel = Array.from(this.whiteLabels.values())
      .find(wl => wl.enterpriseId === enterpriseId);
    
    const supportConfig = this.dedicatedSupport.get(enterpriseId);
    
    const openTickets = Array.from(this.supportTickets.values())
      .filter(ticket => ticket.enterpriseId === enterpriseId && ticket.status === 'OPEN');
    
    return {
      enterprise,
      integrations,
      whiteLabel,
      supportConfig,
      openTickets: openTickets.length,
      features: enterprise.features,
      usage: enterprise.usage
    };
  }

  /**
   * Placeholder methods for complex operations
   */
  async validateIntegrationConfig(integration) {
    return { valid: true, errors: [] };
  }
  
  async testIntegration(integration) {
    return { success: true, message: 'Integration test passed' };
  }
  
  async deployWhiteLabelInstance(whiteLabel) {
    return { status: 'DEPLOYED', url: `https://${whiteLabel.domain}` };
  }
  
  async autoAssignTicket(ticket) {
    return 'enterprise-support-team';
  }
  
  async sendTicketNotifications(ticket) {
    console.log(`📧 Ticket notifications sent for ${ticket.ticketId}`);
  }
  
  async generateUsageReport(enterprise, config) {
    return { totalUsers: enterprise.usage.activeUsers, totalLicenses: enterprise.usage.totalLicenses };
  }
  
  async generateFinancialReport(enterprise, config) {
    return { revenue: 50000, costs: 15000, profit: 35000 };
  }
  
  async generatePerformanceReport(enterprise, config) {
    return { uptime: 99.9, responseTime: 150, errorRate: 0.01 };
  }
  
  async generateSecurityReport(enterprise, config) {
    return { securityEvents: 0, vulnerabilities: 0, complianceScore: 100 };
  }
  
  async createEnterpriseLicense(enterpriseId, licenseData) {
    return { licenseId: 'ENT-LIC-' + Date.now(), status: 'CREATED' };
  }
  
  async updateEnterpriseLicense(enterpriseId, licenseData) {
    return { licenseId: licenseData.licenseId, status: 'UPDATED' };
  }
  
  async deactivateEnterpriseLicense(enterpriseId, licenseData) {
    return { licenseId: licenseData.licenseId, status: 'DEACTIVATED' };
  }
  
  async transferEnterpriseLicense(enterpriseId, licenseData) {
    return { licenseId: licenseData.licenseId, status: 'TRANSFERRED' };
  }
}
