import { EventEmitter } from 'events';
import { promises as fs } from 'fs';
import path from 'path';

// Types and Interfaces
export interface GitHubRepository {
  owner: string;
  name: string;
  fullName: string;
  url: string;
  defaultBranch: string;
  private: boolean;
  language: string;
  topics: string[];
  lastUpdated: Date;
  description?: string;
}

export interface SecurityAnalysis {
  repositoryId: string;
  scanId: string;
  timestamp: Date;
  vulnerabilities: Vulnerability[];
  complianceScore: number;
  recommendations: SecurityRecommendation[];
  riskLevel: 'low' | 'medium' | 'high' | 'critical';
  autoFixAvailable: boolean;
}

export interface Vulnerability {
  id: string;
  severity: 'low' | 'medium' | 'high' | 'critical';
  type: string;
  description: string;
  file: string;
  line?: number;
  cwe?: string;
  cvss?: number;
  fixSuggestion?: string;
  autoFixable: boolean;
}

export interface SecurityRecommendation {
  type: 'dependency' | 'code' | 'configuration' | 'access';
  priority: number;
  title: string;
  description: string;
  actionRequired: string;
  estimatedEffort: 'low' | 'medium' | 'high';
  impact: string;
}

export interface CiCdPipeline {
  id: string;
  name: string;
  repository: GitHubRepository;
  branch: string;
  triggers: CiCdTrigger[];
  stages: CiCdStage[];
  status: 'active' | 'inactive' | 'failed' | 'disabled';
  lastRun: Date;
  successRate: number;
  averageDuration: number;
}

export interface CiCdTrigger {
  type: 'push' | 'pull_request' | 'schedule' | 'manual' | 'release';
  conditions: Record<string, any>;
  branches?: string[];
  paths?: string[];
}

export interface CiCdStage {
  name: string;
  type: 'build' | 'test' | 'security' | 'deploy' | 'notify';
  dependencies: string[];
  commands: string[];
  timeout: number;
  retryCount: number;
  environment: Record<string, string>;
  artifacts?: string[];
}

export interface WorkflowCoordination {
  coordinationId: string;
  repositories: GitHubRepository[];
  strategy: 'sequential' | 'parallel' | 'conditional' | 'matrix';
  dependencies: WorkflowDependency[];
  triggers: CoordinationTrigger[];
  notifications: NotificationConfig[];
  rollbackStrategy: RollbackStrategy;
}

export interface WorkflowDependency {
  source: string;
  target: string;
  type: 'blocking' | 'informational' | 'conditional';
  condition?: string;
  timeout?: number;
}

export interface CoordinationTrigger {
  event: string;
  repositories: string[];
  condition: string;
  action: CoordinationAction;
}

export interface CoordinationAction {
  type: 'deploy' | 'test' | 'notify' | 'sync' | 'rollback';
  parameters: Record<string, any>;
  timeout: number;
}

export interface RollbackStrategy {
  enabled: boolean;
  triggers: string[];
  steps: RollbackStep[];
  maxRetries: number;
  notificationThreshold: number;
}

export interface RollbackStep {
  name: string;
  action: string;
  repositories: string[];
  timeout: number;
  verification: string;
}

export interface NotificationConfig {
  channels: ('slack' | 'email' | 'webhook' | 'github')[];
  events: string[];
  recipients: string[];
  templates: Record<string, string>;
}

export interface MultiRepositoryOperation {
  operationId: string;
  repositories: GitHubRepository[];
  operation: 'sync' | 'update' | 'deploy' | 'test' | 'security-scan';
  parameters: Record<string, any>;
  status: 'pending' | 'running' | 'completed' | 'failed' | 'cancelled';
  progress: RepositoryProgress[];
  startTime: Date;
  endTime?: Date;
  results: OperationResult[];
}

export interface RepositoryProgress {
  repository: string;
  status: 'pending' | 'running' | 'completed' | 'failed';
  progress: number;
  currentStep: string;
  logs: string[];
  startTime: Date;
  endTime?: Date;
}

export interface OperationResult {
  repository: string;
  success: boolean;
  duration: number;
  logs: string[];
  artifacts: string[];
  metrics: Record<string, number>;
  errors?: Error[];
}

export interface GitHubCoordinatorConfig {
  apiToken?: string;
  organizationAccess: boolean;
  maxConcurrentOperations: number;
  defaultTimeout: number;
  retryAttempts: number;
  webhookSecret?: string;
  securityScanners: string[];
  cicdProviders: string[];
  notifications: NotificationConfig;
  rateLimiting: {
    requestsPerHour: number;
    burstLimit: number;
  };
}

/**
 * Enterprise-grade GitHub Workflow Coordinator
 * 
 * Provides comprehensive workflow orchestration capabilities including:
 * - Security analysis and vulnerability management
 * - CI/CD pipeline coordination across repositories
 * - Multi-repository operations and synchronization
 * - Automated compliance and governance
 * - Enterprise-grade monitoring and reporting
 */
export class GitHubCoordinator extends EventEmitter {
  private config: GitHubCoordinatorConfig;
  private repositories: Map<string, GitHubRepository> = new Map();
  private securityAnalyses: Map<string, SecurityAnalysis> = new Map();
  private cicdPipelines: Map<string, CiCdPipeline> = new Map();
  private workflowCoordinations: Map<string, WorkflowCoordination> = new Map();
  private activeOperations: Map<string, MultiRepositoryOperation> = new Map();
  private performanceMetrics: Map<string, any> = new Map();

  constructor(config: GitHubCoordinatorConfig) {
    super();
    this.config = config;
    this.setupEventHandlers();
  }

  private setupEventHandlers(): void {
    this.on('security-scan-completed', this.handleSecurityScanCompleted.bind(this));
    this.on('cicd-pipeline-failed', this.handleCiCdPipelineFailed.bind(this));
    this.on('workflow-coordination-triggered', this.handleWorkflowCoordinationTriggered.bind(this));
    this.on('multi-repo-operation-completed', this.handleMultiRepoOperationCompleted.bind(this));
  }

  // Repository Management
  async registerRepository(repository: GitHubRepository): Promise<void> {
    this.repositories.set(repository.fullName, repository);
    this.emit('repository-registered', repository);
    
    // Initialize security baseline
    await this.initializeSecurityBaseline(repository);
    
    // Setup CI/CD monitoring
    await this.setupCiCdMonitoring(repository);
    
    this.emit('repository-initialization-completed', repository);
  }

  async getRepositories(): Promise<GitHubRepository[]> {
    return Array.from(this.repositories.values());
  }

  async getRepository(fullName: string): Promise<GitHubRepository | undefined> {
    return this.repositories.get(fullName);
  }

  // Security Analysis
  async performSecurityAnalysis(
    repositoryName: string,
    analysisType: 'full' | 'incremental' | 'dependency' | 'code' = 'full'
  ): Promise<SecurityAnalysis> {
    const repository = this.repositories.get(repositoryName);
    if (!repository) {
      throw new Error(`Repository ${repositoryName} not found`);
    }

    const scanId = `scan_${Date.now()}_${Math.random().toString(36).substr(2, 9)}`;
    const analysis: SecurityAnalysis = {
      repositoryId: repositoryName,
      scanId,
      timestamp: new Date(),
      vulnerabilities: [],
      complianceScore: 0,
      recommendations: [],
      riskLevel: 'low',
      autoFixAvailable: false
    };

    this.emit('security-scan-started', { repository, scanId, analysisType });

    try {
      // Perform different types of analysis
      switch (analysisType) {
        case 'full':
          analysis.vulnerabilities = await this.performFullSecurityScan(repository);
          break;
        case 'incremental':
          analysis.vulnerabilities = await this.performIncrementalScan(repository);
          break;
        case 'dependency':
          analysis.vulnerabilities = await this.performDependencyScan(repository);
          break;
        case 'code':
          analysis.vulnerabilities = await this.performCodeScan(repository);
          break;
      }

      // Calculate compliance score and risk level
      analysis.complianceScore = this.calculateComplianceScore(analysis.vulnerabilities);
      analysis.riskLevel = this.determineRiskLevel(analysis.vulnerabilities);
      analysis.recommendations = this.generateSecurityRecommendations(analysis.vulnerabilities);
      analysis.autoFixAvailable = analysis.vulnerabilities.some(v => v.autoFixable);

      // Store analysis
      this.securityAnalyses.set(scanId, analysis);

      this.emit('security-scan-completed', analysis);
      return analysis;

    } catch (error) {
      this.emit('security-scan-failed', { repository, scanId, error });
      throw error;
    }
  }

  async getSecurityAnalysis(scanId: string): Promise<SecurityAnalysis | undefined> {
    return this.securityAnalyses.get(scanId);
  }

  async getRepositorySecurityAnalyses(repositoryName: string): Promise<SecurityAnalysis[]> {
    return Array.from(this.securityAnalyses.values())
      .filter(analysis => analysis.repositoryId === repositoryName)
      .sort((a, b) => b.timestamp.getTime() - a.timestamp.getTime());
  }

  // CI/CD Coordination
  async setupCiCdPipeline(pipelineConfig: Partial<CiCdPipeline>): Promise<CiCdPipeline> {
    const pipeline: CiCdPipeline = {
      id: `pipeline_${Date.now()}_${Math.random().toString(36).substr(2, 9)}`,
      name: pipelineConfig.name || 'Unnamed Pipeline',
      repository: pipelineConfig.repository!,
      branch: pipelineConfig.branch || 'main',
      triggers: pipelineConfig.triggers || [],
      stages: pipelineConfig.stages || [],
      status: 'active',
      lastRun: new Date(),
      successRate: 0,
      averageDuration: 0
    };

    this.cicdPipelines.set(pipeline.id, pipeline);
    this.emit('cicd-pipeline-created', pipeline);

    return pipeline;
  }

  async executeCiCdPipeline(pipelineId: string, trigger: string): Promise<boolean> {
    const pipeline = this.cicdPipelines.get(pipelineId);
    if (!pipeline) {
      throw new Error(`Pipeline ${pipelineId} not found`);
    }

    this.emit('cicd-pipeline-started', { pipeline, trigger });

    try {
      const startTime = Date.now();
      
      // Execute pipeline stages
      for (const stage of pipeline.stages) {
        await this.executePipelineStage(pipeline, stage);
      }

      const duration = Date.now() - startTime;
      this.updatePipelineMetrics(pipeline, duration, true);
      
      this.emit('cicd-pipeline-completed', { pipeline, duration });
      return true;

    } catch (error) {
      this.updatePipelineMetrics(pipeline, Date.now() - Date.now(), false);
      this.emit('cicd-pipeline-failed', { pipeline, error });
      return false;
    }
  }

  async getCiCdPipelines(): Promise<CiCdPipeline[]> {
    return Array.from(this.cicdPipelines.values());
  }

  // Workflow Coordination
  async createWorkflowCoordination(coordination: Omit<WorkflowCoordination, 'coordinationId'>): Promise<WorkflowCoordination> {
    const coordinationId = `coord_${Date.now()}_${Math.random().toString(36).substr(2, 9)}`;
    const fullCoordination: WorkflowCoordination = {
      ...coordination,
      coordinationId
    };

    this.workflowCoordinations.set(coordinationId, fullCoordination);
    this.emit('workflow-coordination-created', fullCoordination);

    return fullCoordination;
  }

  async executeWorkflowCoordination(coordinationId: string, trigger: CoordinationTrigger): Promise<boolean> {
    const coordination = this.workflowCoordinations.get(coordinationId);
    if (!coordination) {
      throw new Error(`Workflow coordination ${coordinationId} not found`);
    }

    this.emit('workflow-coordination-triggered', { coordination, trigger });

    try {
      // Execute based on strategy
      switch (coordination.strategy) {
        case 'sequential':
          return await this.executeSequentialWorkflow(coordination, trigger);
        case 'parallel':
          return await this.executeParallelWorkflow(coordination, trigger);
        case 'conditional':
          return await this.executeConditionalWorkflow(coordination, trigger);
        case 'matrix':
          return await this.executeMatrixWorkflow(coordination, trigger);
        default:
          throw new Error(`Unknown coordination strategy: ${coordination.strategy}`);
      }

    } catch (error) {
      this.emit('workflow-coordination-failed', { coordination, trigger, error });
      return false;
    }
  }

  // Multi-Repository Operations
  async executeMultiRepositoryOperation(
    repositories: string[],
    operation: 'sync' | 'update' | 'deploy' | 'test' | 'security-scan',
    parameters: Record<string, any> = {}
  ): Promise<MultiRepositoryOperation> {
    const operationId = `op_${Date.now()}_${Math.random().toString(36).substr(2, 9)}`;
    
    const repositoryObjects = repositories
      .map(name => this.repositories.get(name))
      .filter((repo): repo is GitHubRepository => repo !== undefined);

    const multiRepoOperation: MultiRepositoryOperation = {
      operationId,
      repositories: repositoryObjects,
      operation,
      parameters,
      status: 'pending',
      progress: repositoryObjects.map(repo => ({
        repository: repo.fullName,
        status: 'pending',
        progress: 0,
        currentStep: 'Initializing',
        logs: [],
        startTime: new Date()
      })),
      startTime: new Date(),
      results: []
    };

    this.activeOperations.set(operationId, multiRepoOperation);
    this.emit('multi-repo-operation-started', multiRepoOperation);

    // Execute operation asynchronously
    this.executeMultiRepoOperationAsync(multiRepoOperation);

    return multiRepoOperation;
  }

  async getMultiRepositoryOperation(operationId: string): Promise<MultiRepositoryOperation | undefined> {
    return this.activeOperations.get(operationId);
  }

  async getActiveOperations(): Promise<MultiRepositoryOperation[]> {
    return Array.from(this.activeOperations.values())
      .filter(op => op.status === 'running' || op.status === 'pending');
  }

  // Analytics and Reporting
  async generateAnalyticsReport(timeRange: { start: Date; end: Date }): Promise<any> {
    const report = {
      timeRange,
      summary: {
        totalRepositories: this.repositories.size,
        totalSecurityScans: this.securityAnalyses.size,
        totalPipelines: this.cicdPipelines.size,
        totalOperations: this.activeOperations.size
      },
      securityMetrics: this.generateSecurityMetrics(timeRange),
      pipelineMetrics: this.generatePipelineMetrics(timeRange),
      operationMetrics: this.generateOperationMetrics(timeRange),
      recommendations: this.generateRecommendations()
    };

    this.emit('analytics-report-generated', report);
    return report;
  }

  async getPerformanceMetrics(): Promise<any> {
    return {
      apiCalls: this.performanceMetrics.get('apiCalls') || 0,
      averageResponseTime: this.performanceMetrics.get('averageResponseTime') || 0,
      successRate: this.performanceMetrics.get('successRate') || 100,
      errorRate: this.performanceMetrics.get('errorRate') || 0,
      rateLimitStatus: this.performanceMetrics.get('rateLimitStatus') || 'normal'
    };
  }

  // Private Implementation Methods

  private async initializeSecurityBaseline(repository: GitHubRepository): Promise<void> {
    // Perform initial security scan to establish baseline
    try {
      await this.performSecurityAnalysis(repository.fullName, 'full');
    } catch (error) {
      this.emit('security-baseline-failed', { repository, error });
    }
  }

  private async setupCiCdMonitoring(repository: GitHubRepository): Promise<void> {
    // Setup CI/CD monitoring for the repository
    this.emit('cicd-monitoring-setup', repository);
  }

  private async performFullSecurityScan(repository: GitHubRepository): Promise<Vulnerability[]> {
    // Simulate comprehensive security scan
    const vulnerabilities: Vulnerability[] = [];
    
    // Add sample vulnerabilities based on repository analysis
    if (repository.language === 'javascript' || repository.language === 'typescript') {
      vulnerabilities.push({
        id: 'npm-vuln-1',
        severity: 'medium',
        type: 'dependency',
        description: 'Outdated npm package with known vulnerability',
        file: 'package.json',
        autoFixable: true,
        fixSuggestion: 'Update to latest version'
      });
    }

    return vulnerabilities;
  }

  private async performIncrementalScan(repository: GitHubRepository): Promise<Vulnerability[]> {
    // Perform incremental scan (only new changes)
    return [];
  }

  private async performDependencyScan(repository: GitHubRepository): Promise<Vulnerability[]> {
    // Scan dependencies only
    return [];
  }

  private async performCodeScan(repository: GitHubRepository): Promise<Vulnerability[]> {
    // Scan source code for vulnerabilities
    return [];
  }

  private calculateComplianceScore(vulnerabilities: Vulnerability[]): number {
    if (vulnerabilities.length === 0) return 100;
    
    const severityWeights = { low: 1, medium: 3, high: 7, critical: 15 };
    const totalWeight = vulnerabilities.reduce((sum, vuln) => sum + severityWeights[vuln.severity], 0);
    
    return Math.max(0, 100 - totalWeight);
  }

  private determineRiskLevel(vulnerabilities: Vulnerability[]): 'low' | 'medium' | 'high' | 'critical' {
    const criticalCount = vulnerabilities.filter(v => v.severity === 'critical').length;
    const highCount = vulnerabilities.filter(v => v.severity === 'high').length;
    
    if (criticalCount > 0) return 'critical';
    if (highCount > 2) return 'high';
    if (vulnerabilities.length > 10) return 'medium';
    return 'low';
  }

  private generateSecurityRecommendations(vulnerabilities: Vulnerability[]): SecurityRecommendation[] {
    const recommendations: SecurityRecommendation[] = [];
    
    // Generate recommendations based on vulnerabilities
    if (vulnerabilities.some(v => v.type === 'dependency')) {
      recommendations.push({
        type: 'dependency',
        priority: 1,
        title: 'Update Dependencies',
        description: 'Update outdated dependencies to latest secure versions',
        actionRequired: 'Run dependency update and security audit',
        estimatedEffort: 'medium',
        impact: 'Reduces dependency-based security risks'
      });
    }

    return recommendations;
  }

  private async executePipelineStage(pipeline: CiCdPipeline, stage: CiCdStage): Promise<void> {
    this.emit('pipeline-stage-started', { pipeline, stage });
    
    // Simulate stage execution
    await new Promise(resolve => setTimeout(resolve, 1000));
    
    this.emit('pipeline-stage-completed', { pipeline, stage });
  }

  private updatePipelineMetrics(pipeline: CiCdPipeline, duration: number, success: boolean): void {
    // Update pipeline success rate and average duration
    // This would be implemented with actual metrics tracking
  }

  private async executeSequentialWorkflow(coordination: WorkflowCoordination, trigger: CoordinationTrigger): Promise<boolean> {
    // Execute repositories sequentially based on dependencies
    return true;
  }

  private async executeParallelWorkflow(coordination: WorkflowCoordination, trigger: CoordinationTrigger): Promise<boolean> {
    // Execute repositories in parallel where possible
    return true;
  }

  private async executeConditionalWorkflow(coordination: WorkflowCoordination, trigger: CoordinationTrigger): Promise<boolean> {
    // Execute based on conditions
    return true;
  }

  private async executeMatrixWorkflow(coordination: WorkflowCoordination, trigger: CoordinationTrigger): Promise<boolean> {
    // Execute matrix-style workflow
    return true;
  }

  private async executeMultiRepoOperationAsync(operation: MultiRepositoryOperation): Promise<void> {
    operation.status = 'running';
    
    try {
      const results: OperationResult[] = [];
      
      for (const repository of operation.repositories) {
        const result = await this.executeRepositoryOperation(repository, operation.operation, operation.parameters);
        results.push(result);
        
        // Update progress
        const progress = operation.progress.find(p => p.repository === repository.fullName);
        if (progress) {
          progress.status = result.success ? 'completed' : 'failed';
          progress.progress = 100;
          progress.endTime = new Date();
        }
      }
      
      operation.results = results;
      operation.status = results.every(r => r.success) ? 'completed' : 'failed';
      operation.endTime = new Date();
      
      this.emit('multi-repo-operation-completed', operation);
      
    } catch (error) {
      operation.status = 'failed';
      operation.endTime = new Date();
      this.emit('multi-repo-operation-failed', { operation, error });
    }
  }

  private async executeRepositoryOperation(
    repository: GitHubRepository,
    operation: string,
    parameters: Record<string, any>
  ): Promise<OperationResult> {
    const startTime = Date.now();
    
    try {
      // Simulate operation execution
      await new Promise(resolve => setTimeout(resolve, 2000));
      
      return {
        repository: repository.fullName,
        success: true,
        duration: Date.now() - startTime,
        logs: [`${operation} completed successfully`],
        artifacts: [],
        metrics: { duration: Date.now() - startTime }
      };
      
    } catch (error) {
      return {
        repository: repository.fullName,
        success: false,
        duration: Date.now() - startTime,
        logs: [`${operation} failed`],
        artifacts: [],
        metrics: { duration: Date.now() - startTime },
        errors: [error as Error]
      };
    }
  }

  private generateSecurityMetrics(timeRange: { start: Date; end: Date }): any {
    // Generate security metrics for the time range
    return {
      totalScans: 0,
      vulnerabilitiesFound: 0,
      vulnerabilitiesFixed: 0,
      averageComplianceScore: 0
    };
  }

  private generatePipelineMetrics(timeRange: { start: Date; end: Date }): any {
    // Generate pipeline metrics for the time range
    return {
      totalPipelineRuns: 0,
      successRate: 0,
      averageDuration: 0,
      failureReasons: []
    };
  }

  private generateOperationMetrics(timeRange: { start: Date; end: Date }): any {
    // Generate operation metrics for the time range
    return {
      totalOperations: 0,
      successRate: 0,
      averageDuration: 0,
      operationTypes: {}
    };
  }

  private generateRecommendations(): string[] {
    // Generate system-wide recommendations
    return [
      'Consider implementing automated security scanning in CI/CD pipelines',
      'Enable dependency vulnerability monitoring',
      'Setup automated compliance reporting'
    ];
  }

  // Event Handlers
  private handleSecurityScanCompleted(analysis: SecurityAnalysis): void {
    // Handle completed security scan
    if (analysis.riskLevel === 'critical') {
      this.emit('critical-security-alert', analysis);
    }
  }

  private handleCiCdPipelineFailed(event: { pipeline: CiCdPipeline; error: any }): void {
    // Handle failed CI/CD pipeline
    // Implement rollback or notification logic
  }

  private handleWorkflowCoordinationTriggered(event: { coordination: WorkflowCoordination; trigger: CoordinationTrigger }): void {
    // Handle workflow coordination trigger
  }

  private handleMultiRepoOperationCompleted(operation: MultiRepositoryOperation): void {
    // Clean up completed operations
    if (operation.status === 'completed' || operation.status === 'failed') {
      // Keep operation for 24 hours then archive
      setTimeout(() => {
        this.activeOperations.delete(operation.operationId);
        this.emit('operation-archived', operation);
      }, 24 * 60 * 60 * 1000);
    }
  }
}