import { EventEmitter } from 'events';
import { GitHubRepository } from './github-coordinator.js';
import { GitHubUser } from './pull-request-manager.js';

// Types and Interfaces
export interface Release {
  id: string;
  version: string;
  name: string;
  description: string;
  repository: GitHubRepository;
  tagName: string;
  targetCommitish: string;
  branch: string;
  isDraft: boolean;
  isPrerelease: boolean;
  status: 'planning' | 'building' | 'testing' | 'staging' | 'published' | 'failed' | 'cancelled';
  releaseType: 'major' | 'minor' | 'patch' | 'hotfix' | 'beta' | 'alpha';
  createdAt: Date;
  publishedAt?: Date;
  author: GitHubUser;
  changelog: Changelog;
  assets: ReleaseAsset[];
  deployments: Deployment[];
  approvals: ReleaseApproval[];
  rollbackPlan: RollbackPlan;
  dependencies: ReleaseDependency[];
  metadata: Record<string, any>;
}

export interface Changelog {
  version: string;
  releaseDate: Date;
  sections: ChangelogSection[];
  summary: string;
  breaking_changes: BreakingChange[];
  contributors: GitHubUser[];
  statistics: ChangelogStatistics;
  template: string;
  autoGenerated: boolean;
}

export interface ChangelogSection {
  title: string;
  type: 'features' | 'fixes' | 'improvements' | 'security' | 'deprecations' | 'removals' | 'docs' | 'internal';
  items: ChangelogItem[];
  priority: number;
}

export interface ChangelogItem {
  id: string;
  description: string;
  type: string;
  scope?: string;
  breaking: boolean;
  commit: string;
  pullRequest?: number;
  issue?: number;
  author: GitHubUser;
  impact: 'low' | 'medium' | 'high';
  category: string;
}

export interface BreakingChange {
  description: string;
  migration: string;
  impact: string;
  scope: string;
  before: string;
  after: string;
  reason: string;
}

export interface ChangelogStatistics {
  totalCommits: number;
  totalPullRequests: number;
  totalIssues: number;
  linesAdded: number;
  linesRemoved: number;
  filesChanged: number;
  contributors: number;
  daysInDevelopment: number;
}

export interface ReleaseAsset {
  id: string;
  name: string;
  label?: string;
  contentType: string;
  size: number;
  downloadCount: number;
  uploadedAt: Date;
  uploader: GitHubUser;
  url: string;
  checksum: string;
  signature?: string;
}

export interface Deployment {
  id: string;
  environment: 'development' | 'staging' | 'production' | 'testing' | 'preview';
  status: 'pending' | 'queued' | 'in_progress' | 'success' | 'failure' | 'cancelled' | 'error';
  strategy: 'blue_green' | 'rolling' | 'canary' | 'recreate' | 'immediate';
  startedAt: Date;
  completedAt?: Date;
  duration?: number;
  deployedBy: GitHubUser;
  url?: string;
  logUrl?: string;
  healthChecks: HealthCheck[];
  rollbackAvailable: boolean;
  configuration: DeploymentConfig;
}

export interface HealthCheck {
  id: string;
  name: string;
  url: string;
  method: 'GET' | 'POST' | 'PUT' | 'DELETE';
  expectedStatus: number;
  timeout: number;
  interval: number;
  retries: number;
  status: 'pending' | 'passing' | 'failing' | 'unknown';
  lastChecked?: Date;
  response?: HealthCheckResponse;
}

export interface HealthCheckResponse {
  status: number;
  responseTime: number;
  body?: string;
  headers?: Record<string, string>;
  error?: string;
}

export interface DeploymentConfig {
  replicas?: number;
  resources?: ResourceRequirements;
  environmentVariables?: Record<string, string>;
  secrets?: string[];
  volumes?: VolumeMount[];
  networking?: NetworkConfig;
  scaling?: ScalingConfig;
}

export interface ResourceRequirements {
  cpu: string;
  memory: string;
  storage: string;
}

export interface VolumeMount {
  name: string;
  mountPath: string;
  readOnly: boolean;
}

export interface NetworkConfig {
  ports: number[];
  domains: string[];
  ingress: IngressRule[];
}

export interface IngressRule {
  host: string;
  paths: string[];
  tls: boolean;
}

export interface ScalingConfig {
  minReplicas: number;
  maxReplicas: number;
  targetCpuUtilization: number;
  targetMemoryUtilization: number;
}

export interface ReleaseApproval {
  id: string;
  approver: GitHubUser;
  status: 'pending' | 'approved' | 'rejected' | 'cancelled';
  comment?: string;
  timestamp: Date;
  stage: 'planning' | 'testing' | 'staging' | 'production';
  requirements: ApprovalRequirement[];
}

export interface ApprovalRequirement {
  type: 'manual' | 'automated' | 'security' | 'compliance';
  description: string;
  status: 'pending' | 'satisfied' | 'failed';
  evidence?: string;
  automatedCheck?: string;
}

export interface RollbackPlan {
  id: string;
  version: string;
  strategy: 'immediate' | 'graceful' | 'canary_rollback' | 'blue_green_switch';
  triggers: RollbackTrigger[];
  steps: RollbackStep[];
  estimatedDuration: number;
  impactAssessment: ImpactAssessment;
  communicationPlan: CommunicationPlan;
  validationSteps: ValidationStep[];
}

export interface RollbackTrigger {
  type: 'manual' | 'automated' | 'health_check' | 'metric_threshold' | 'error_rate';
  condition: string;
  threshold?: number;
  enabled: boolean;
  priority: number;
}

export interface RollbackStep {
  id: string;
  name: string;
  description: string;
  type: 'deployment' | 'database' | 'configuration' | 'traffic' | 'verification';
  order: number;
  automatable: boolean;
  command?: string;
  timeout: number;
  dependencies: string[];
  rollbackCommand?: string;
}

export interface ImpactAssessment {
  downtime: number;
  dataLoss: boolean;
  userImpact: 'none' | 'low' | 'medium' | 'high' | 'critical';
  businessImpact: string;
  mitigationSteps: string[];
}

export interface CommunicationPlan {
  channels: ('email' | 'slack' | 'status_page' | 'support_team')[];
  templates: Record<string, string>;
  stakeholders: Stakeholder[];
  escalationPath: string[];
}

export interface Stakeholder {
  name: string;
  role: string;
  contact: string;
  notificationLevel: 'critical' | 'major' | 'minor' | 'all';
}

export interface ValidationStep {
  id: string;
  name: string;
  description: string;
  type: 'health_check' | 'smoke_test' | 'performance_test' | 'manual_verification';
  automatable: boolean;
  timeout: number;
  successCriteria: string;
  command?: string;
}

export interface ReleaseDependency {
  dependentRelease: string;
  dependsOnRelease: string;
  repository: string;
  type: 'hard' | 'soft' | 'recommended';
  status: 'pending' | 'satisfied' | 'failed';
  reason: string;
}

export interface VersionCoordination {
  coordinationId: string;
  repositories: GitHubRepository[];
  targetVersion: string;
  strategy: 'synchronized' | 'sequential' | 'independent' | 'grouped';
  releases: Release[];
  dependencies: CoordinationDependency[];
  timeline: CoordinationTimeline;
  approvals: CoordinationApproval[];
  status: 'planning' | 'executing' | 'completed' | 'failed' | 'cancelled';
}

export interface CoordinationDependency {
  source: string;
  target: string;
  type: 'blocking' | 'preferred' | 'informational';
  delay?: number;
}

export interface CoordinationTimeline {
  phases: CoordinationPhase[];
  milestones: CoordinationMilestone[];
  criticalPath: string[];
}

export interface CoordinationPhase {
  id: string;
  name: string;
  description: string;
  startDate: Date;
  endDate: Date;
  repositories: string[];
  status: 'pending' | 'active' | 'completed' | 'delayed';
}

export interface CoordinationMilestone {
  id: string;
  name: string;
  date: Date;
  type: 'code_freeze' | 'testing_complete' | 'release_ready' | 'deployed';
  status: 'pending' | 'achieved' | 'missed' | 'at_risk';
  dependencies: string[];
}

export interface CoordinationApproval {
  phase: string;
  approver: GitHubUser;
  status: 'pending' | 'approved' | 'rejected';
  comment?: string;
  timestamp: Date;
}

export interface ReleaseManagerConfig {
  autoChangelogGeneration: boolean;
  changelogTemplate: string;
  versioningStrategy: 'semantic' | 'calendar' | 'sequential' | 'custom';
  approvalWorkflow: ApprovalWorkflow;
  deploymentPipelines: DeploymentPipeline[];
  rollbackConfig: RollbackConfig;
  notificationChannels: string[];
  securityScanning: boolean;
  performanceTesting: boolean;
  complianceChecks: string[];
}

export interface ApprovalWorkflow {
  stages: ApprovalStage[];
  parallelApprovals: boolean;
  requireAllApprovals: boolean;
  timeoutHours: number;
  escalationPolicy: EscalationPolicy;
}

export interface ApprovalStage {
  name: string;
  approvers: GitHubUser[];
  requiredApprovals: number;
  autoApprovalRules: AutoApprovalRule[];
  timeout: number;
}

export interface AutoApprovalRule {
  condition: string;
  action: 'approve' | 'reject' | 'escalate';
  confidence: number;
}

export interface EscalationPolicy {
  levels: EscalationLevel[];
  triggerAfterHours: number;
  maxEscalations: number;
}

export interface EscalationLevel {
  level: number;
  approvers: GitHubUser[];
  notificationChannels: string[];
  timeoutHours: number;
}

export interface DeploymentPipeline {
  id: string;
  name: string;
  environments: string[];
  strategy: 'linear' | 'parallel' | 'blue_green' | 'canary';
  triggers: PipelineTrigger[];
  stages: PipelineStage[];
  rollbackStrategy: string;
}

export interface PipelineTrigger {
  type: 'manual' | 'automated' | 'scheduled' | 'approval';
  condition: string;
  enabled: boolean;
}

export interface PipelineStage {
  name: string;
  environment: string;
  approvalRequired: boolean;
  healthChecks: string[];
  timeout: number;
  rollbackOnFailure: boolean;
}

export interface RollbackConfig {
  automaticRollback: boolean;
  rollbackTriggers: string[];
  maxRollbackWindow: number;
  dataProtection: boolean;
  backupRequired: boolean;
}

/**
 * Enterprise-grade Release Manager
 * 
 * Provides comprehensive release management capabilities including:
 * - Automated changelog generation from commits and PRs
 * - Version coordination across multiple repositories
 * - Multi-stage deployment pipelines with approvals
 * - Comprehensive rollback strategies and automation
 * - Release analytics and compliance tracking
 */
export class ReleaseManager extends EventEmitter {
  private config: ReleaseManagerConfig;
  private releases: Map<string, Release> = new Map();
  private versionCoordinations: Map<string, VersionCoordination> = new Map();
  private deploymentPipelines: Map<string, DeploymentPipeline> = new Map();
  private rollbackPlans: Map<string, RollbackPlan> = new Map();
  private changelogs: Map<string, Changelog> = new Map();
  private performanceMetrics: Map<string, any> = new Map();

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

  private setupEventHandlers(): void {
    this.on('release-created', this.handleReleaseCreated.bind(this));
    this.on('deployment-started', this.handleDeploymentStarted.bind(this));
    this.on('deployment-completed', this.handleDeploymentCompleted.bind(this));
    this.on('health-check-failed', this.handleHealthCheckFailed.bind(this));
    this.on('rollback-triggered', this.handleRollbackTriggered.bind(this));
  }

  private initializeDeploymentPipelines(): void {
    this.config.deploymentPipelines.forEach(pipeline => {
      this.deploymentPipelines.set(pipeline.id, pipeline);
    });
  }

  // Release Management
  async createRelease(releaseData: Partial<Release>): Promise<Release> {
    const release: Release = {
      id: `release_${Date.now()}_${Math.random().toString(36).substr(2, 9)}`,
      version: releaseData.version || await this.generateNextVersion(releaseData.repository!),
      name: releaseData.name || `Release ${releaseData.version}`,
      description: releaseData.description || '',
      repository: releaseData.repository!,
      tagName: releaseData.tagName || `v${releaseData.version}`,
      targetCommitish: releaseData.targetCommitish || 'main',
      branch: releaseData.branch || 'main',
      isDraft: releaseData.isDraft || true,
      isPrerelease: releaseData.isPrerelease || false,
      status: 'planning',
      releaseType: releaseData.releaseType || 'minor',
      createdAt: new Date(),
      author: releaseData.author!,
      changelog: await this.generateChangelog(releaseData.repository!, releaseData.version!),
      assets: [],
      deployments: [],
      approvals: [],
      rollbackPlan: await this.createRollbackPlan(releaseData.version!),
      dependencies: [],
      metadata: releaseData.metadata || {}
    };

    this.releases.set(release.id, release);
    this.emit('release-created', release);

    return release;
  }

  async getRelease(id: string): Promise<Release | undefined> {
    return this.releases.get(id);
  }

  async updateRelease(id: string, updates: Partial<Release>): Promise<Release> {
    const release = this.releases.get(id);
    if (!release) {
      throw new Error(`Release ${id} not found`);
    }

    const updatedRelease = { ...release, ...updates };
    this.releases.set(id, updatedRelease);

    this.emit('release-updated', updatedRelease);
    return updatedRelease;
  }

  // Automated Changelog Generation
  async generateChangelog(repository: GitHubRepository, version: string): Promise<Changelog> {
    const cacheKey = `${repository.fullName}_${version}`;
    const cachedChangelog = this.changelogs.get(cacheKey);
    if (cachedChangelog) {
      return cachedChangelog;
    }

    this.emit('changelog-generation-started', { repository, version });

    try {
      // Get commits since last release
      const commits = await this.getCommitsSinceLastRelease(repository);
      
      // Get pull requests for this release
      const pullRequests = await this.getPullRequestsForRelease(repository, version);
      
      // Get issues closed in this release
      const closedIssues = await this.getClosedIssuesForRelease(repository, version);

      // Categorize changes
      const sections = await this.categorizeChanges(commits, pullRequests, closedIssues);
      
      // Identify breaking changes
      const breakingChanges = await this.identifyBreakingChanges(commits, pullRequests);
      
      // Calculate statistics
      const statistics = await this.calculateChangelogStatistics(commits, pullRequests, closedIssues);
      
      // Get contributors
      const contributors = await this.getContributors(commits, pullRequests);

      const changelog: Changelog = {
        version,
        releaseDate: new Date(),
        sections,
        summary: await this.generateReleaseSummary(sections, statistics),
        breaking_changes: breakingChanges,
        contributors,
        statistics,
        template: this.config.changelogTemplate,
        autoGenerated: true
      };

      this.changelogs.set(cacheKey, changelog);
      this.emit('changelog-generated', changelog);

      return changelog;

    } catch (error) {
      this.emit('changelog-generation-failed', { repository, version, error });
      throw error;
    }
  }

  // Version Coordination
  async createVersionCoordination(
    repositories: GitHubRepository[],
    targetVersion: string,
    strategy: 'synchronized' | 'sequential' | 'independent' | 'grouped'
  ): Promise<VersionCoordination> {
    const coordination: VersionCoordination = {
      coordinationId: `coord_${Date.now()}_${Math.random().toString(36).substr(2, 9)}`,
      repositories,
      targetVersion,
      strategy,
      releases: [],
      dependencies: [],
      timeline: {
        phases: [],
        milestones: [],
        criticalPath: []
      },
      approvals: [],
      status: 'planning'
    };

    // Create releases for each repository
    for (const repository of repositories) {
      const release = await this.createRelease({
        version: targetVersion,
        repository,
        author: { id: 'system', username: 'release-manager', type: 'bot', permissions: [] },
        releaseType: 'minor'
      });
      coordination.releases.push(release);
    }

    // Build coordination timeline
    coordination.timeline = await this.buildCoordinationTimeline(coordination);

    this.versionCoordinations.set(coordination.coordinationId, coordination);
    this.emit('version-coordination-created', coordination);

    return coordination;
  }

  async executeVersionCoordination(coordinationId: string): Promise<boolean> {
    const coordination = this.versionCoordinations.get(coordinationId);
    if (!coordination) {
      throw new Error(`Version coordination ${coordinationId} not found`);
    }

    coordination.status = 'executing';
    this.emit('version-coordination-started', coordination);

    try {
      switch (coordination.strategy) {
        case 'synchronized':
          return await this.executeSynchronizedRelease(coordination);
        case 'sequential':
          return await this.executeSequentialRelease(coordination);
        case 'independent':
          return await this.executeIndependentRelease(coordination);
        case 'grouped':
          return await this.executeGroupedRelease(coordination);
        default:
          throw new Error(`Unknown coordination strategy: ${coordination.strategy}`);
      }
    } catch (error) {
      coordination.status = 'failed';
      this.emit('version-coordination-failed', { coordination, error });
      return false;
    }
  }

  // Deployment Pipelines
  async deployRelease(releaseId: string, pipelineId?: string): Promise<boolean> {
    const release = this.releases.get(releaseId);
    if (!release) {
      throw new Error(`Release ${releaseId} not found`);
    }

    const pipeline = pipelineId 
      ? this.deploymentPipelines.get(pipelineId)
      : this.deploymentPipelines.values().next().value;

    if (!pipeline) {
      throw new Error('No deployment pipeline available');
    }

    this.emit('deployment-pipeline-started', { release, pipeline });

    try {
      // Execute deployment stages
      for (const stage of pipeline.stages) {
        const deployment = await this.executeDeploymentStage(release, stage, pipeline);
        release.deployments.push(deployment);
        
        if (deployment.status === 'failure') {
          if (stage.rollbackOnFailure) {
            await this.triggerRollback(releaseId, 'deployment_failure');
          }
          return false;
        }
      }

      release.status = 'published';
      release.publishedAt = new Date();
      
      this.emit('deployment-pipeline-completed', { release, pipeline });
      return true;

    } catch (error) {
      this.emit('deployment-pipeline-failed', { release, pipeline, error });
      return false;
    }
  }

  // Rollback Capabilities
  async createRollbackPlan(version: string): Promise<RollbackPlan> {
    const rollbackPlan: RollbackPlan = {
      id: `rollback_${Date.now()}_${Math.random().toString(36).substr(2, 9)}`,
      version,
      strategy: 'graceful',
      triggers: [
        {
          type: 'health_check',
          condition: 'health_score < 0.8',
          threshold: 0.8,
          enabled: true,
          priority: 1
        },
        {
          type: 'error_rate',
          condition: 'error_rate > 5%',
          threshold: 5,
          enabled: true,
          priority: 2
        }
      ],
      steps: [
        {
          id: 'traffic_diversion',
          name: 'Divert Traffic',
          description: 'Gradually divert traffic from new version',
          type: 'traffic',
          order: 1,
          automatable: true,
          timeout: 300000, // 5 minutes
          dependencies: []
        },
        {
          id: 'database_rollback',
          name: 'Rollback Database',
          description: 'Restore database to previous state if needed',
          type: 'database',
          order: 2,
          automatable: false,
          timeout: 600000, // 10 minutes
          dependencies: ['traffic_diversion']
        },
        {
          id: 'deployment_rollback',
          name: 'Rollback Deployment',
          description: 'Deploy previous version',
          type: 'deployment',
          order: 3,
          automatable: true,
          timeout: 900000, // 15 minutes
          dependencies: ['database_rollback']
        },
        {
          id: 'verification',
          name: 'Verify Rollback',
          description: 'Verify system is working correctly',
          type: 'verification',
          order: 4,
          automatable: true,
          timeout: 300000, // 5 minutes
          dependencies: ['deployment_rollback']
        }
      ],
      estimatedDuration: 1800000, // 30 minutes
      impactAssessment: {
        downtime: 600000, // 10 minutes
        dataLoss: false,
        userImpact: 'medium',
        businessImpact: 'Service temporarily degraded during rollback',
        mitigationSteps: [
          'Display maintenance message',
          'Queue non-critical operations',
          'Notify customer support team'
        ]
      },
      communicationPlan: {
        channels: ['slack', 'email', 'status_page'],
        templates: {
          rollback_started: 'Rollback initiated for version {{version}}',
          rollback_completed: 'Rollback completed successfully',
          rollback_failed: 'Rollback failed - manual intervention required'
        },
        stakeholders: [
          {
            name: 'Engineering Team',
            role: 'Technical Response',
            contact: 'engineering@company.com',
            notificationLevel: 'all'
          },
          {
            name: 'Product Manager',
            role: 'Business Impact',
            contact: 'product@company.com',
            notificationLevel: 'major'
          }
        ],
        escalationPath: ['team-lead', 'engineering-manager', 'cto']
      },
      validationSteps: [
        {
          id: 'health_check',
          name: 'Health Check',
          description: 'Verify all services are healthy',
          type: 'health_check',
          automatable: true,
          timeout: 60000,
          successCriteria: 'All health checks pass'
        },
        {
          id: 'smoke_test',
          name: 'Smoke Test',
          description: 'Run basic functionality tests',
          type: 'smoke_test',
          automatable: true,
          timeout: 300000,
          successCriteria: 'All smoke tests pass'
        }
      ]
    };

    this.rollbackPlans.set(rollbackPlan.id, rollbackPlan);
    return rollbackPlan;
  }

  async triggerRollback(releaseId: string, reason: string): Promise<boolean> {
    const release = this.releases.get(releaseId);
    if (!release) {
      throw new Error(`Release ${releaseId} not found`);
    }

    const rollbackPlan = release.rollbackPlan;
    this.emit('rollback-triggered', { release, rollbackPlan, reason });

    try {
      // Execute rollback steps in order
      for (const step of rollbackPlan.steps.sort((a, b) => a.order - b.order)) {
        await this.executeRollbackStep(release, step);
      }

      // Validate rollback
      for (const validation of rollbackPlan.validationSteps) {
        const isValid = await this.executeValidationStep(validation);
        if (!isValid) {
          throw new Error(`Validation failed: ${validation.name}`);
        }
      }

      release.status = 'failed'; // Mark original release as failed
      
      this.emit('rollback-completed', { release, rollbackPlan });
      return true;

    } catch (error) {
      this.emit('rollback-failed', { release, rollbackPlan, error });
      return false;
    }
  }

  // Analytics and Reporting
  async generateReleaseAnalytics(timeRange: { start: Date; end: Date }): Promise<any> {
    const releasesInRange = Array.from(this.releases.values())
      .filter(release => release.createdAt >= timeRange.start && release.createdAt <= timeRange.end);

    const analytics = {
      totalReleases: releasesInRange.length,
      successfulReleases: releasesInRange.filter(r => r.status === 'published').length,
      failedReleases: releasesInRange.filter(r => r.status === 'failed').length,
      averageReleaseTime: this.calculateAverageReleaseTime(releasesInRange),
      deploymentFrequency: this.calculateDeploymentFrequency(releasesInRange),
      leadTime: this.calculateLeadTime(releasesInRange),
      mttr: this.calculateMTTR(releasesInRange),
      changeFailureRate: this.calculateChangeFailureRate(releasesInRange),
      rollbackRate: this.calculateRollbackRate(releasesInRange),
      releasesByType: this.groupReleasesByType(releasesInRange),
      topContributors: this.getTopContributors(releasesInRange),
      releaseVelocity: this.calculateReleaseVelocity(releasesInRange)
    };

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

  // Private Implementation Methods

  private async generateNextVersion(repository: GitHubRepository): Promise<string> {
    // Get current version from repository
    const currentVersion = await this.getCurrentVersion(repository);
    
    // Generate next version based on strategy
    switch (this.config.versioningStrategy) {
      case 'semantic':
        return this.incrementSemanticVersion(currentVersion, 'minor');
      case 'calendar':
        return this.generateCalendarVersion();
      case 'sequential':
        return this.incrementSequentialVersion(currentVersion);
      default:
        return this.incrementSemanticVersion(currentVersion, 'minor');
    }
  }

  private async getCurrentVersion(repository: GitHubRepository): Promise<string> {
    // Simulate getting current version from repository tags
    return '1.0.0';
  }

  private incrementSemanticVersion(version: string, type: 'major' | 'minor' | 'patch'): string {
    const [major, minor, patch] = version.split('.').map(Number);
    
    switch (type) {
      case 'major':
        return `${major + 1}.0.0`;
      case 'minor':
        return `${major}.${minor + 1}.0`;
      case 'patch':
        return `${major}.${minor}.${patch + 1}`;
      default:
        return version;
    }
  }

  private generateCalendarVersion(): string {
    const now = new Date();
    const year = now.getFullYear();
    const month = String(now.getMonth() + 1).padStart(2, '0');
    const day = String(now.getDate()).padStart(2, '0');
    return `${year}.${month}.${day}`;
  }

  private incrementSequentialVersion(version: string): string {
    const versionNumber = parseInt(version) || 1;
    return (versionNumber + 1).toString();
  }

  private async getCommitsSinceLastRelease(repository: GitHubRepository): Promise<any[]> {
    // Simulate getting commits since last release
    return [];
  }

  private async getPullRequestsForRelease(repository: GitHubRepository, version: string): Promise<any[]> {
    // Simulate getting PRs for release
    return [];
  }

  private async getClosedIssuesForRelease(repository: GitHubRepository, version: string): Promise<any[]> {
    // Simulate getting closed issues
    return [];
  }

  private async categorizeChanges(commits: any[], pullRequests: any[], issues: any[]): Promise<ChangelogSection[]> {
    const sections: ChangelogSection[] = [
      { title: 'Features', type: 'features', items: [], priority: 1 },
      { title: 'Bug Fixes', type: 'fixes', items: [], priority: 2 },
      { title: 'Improvements', type: 'improvements', items: [], priority: 3 },
      { title: 'Security', type: 'security', items: [], priority: 4 },
      { title: 'Documentation', type: 'docs', items: [], priority: 5 }
    ];

    // Categorize commits, PRs, and issues into appropriate sections
    // This would involve parsing commit messages, PR titles, etc.

    return sections.filter(section => section.items.length > 0);
  }

  private async identifyBreakingChanges(commits: any[], pullRequests: any[]): Promise<BreakingChange[]> {
    // Identify breaking changes from commits and PRs
    return [];
  }

  private async calculateChangelogStatistics(commits: any[], pullRequests: any[], issues: any[]): Promise<ChangelogStatistics> {
    return {
      totalCommits: commits.length,
      totalPullRequests: pullRequests.length,
      totalIssues: issues.length,
      linesAdded: 0,
      linesRemoved: 0,
      filesChanged: 0,
      contributors: 0,
      daysInDevelopment: 14
    };
  }

  private async getContributors(commits: any[], pullRequests: any[]): Promise<GitHubUser[]> {
    // Extract unique contributors
    return [];
  }

  private async generateReleaseSummary(sections: ChangelogSection[], statistics: ChangelogStatistics): Promise<string> {
    const featureCount = sections.find(s => s.type === 'features')?.items.length || 0;
    const fixCount = sections.find(s => s.type === 'fixes')?.items.length || 0;
    
    return `This release includes ${featureCount} new features and ${fixCount} bug fixes, with ${statistics.totalCommits} commits from ${statistics.contributors} contributors.`;
  }

  private async buildCoordinationTimeline(coordination: VersionCoordination): Promise<CoordinationTimeline> {
    const timeline: CoordinationTimeline = {
      phases: [
        {
          id: 'preparation',
          name: 'Preparation',
          description: 'Prepare releases for all repositories',
          startDate: new Date(),
          endDate: new Date(Date.now() + 7 * 24 * 60 * 60 * 1000),
          repositories: coordination.repositories.map(r => r.fullName),
          status: 'pending'
        },
        {
          id: 'testing',
          name: 'Testing',
          description: 'Test all releases',
          startDate: new Date(Date.now() + 7 * 24 * 60 * 60 * 1000),
          endDate: new Date(Date.now() + 14 * 24 * 60 * 60 * 1000),
          repositories: coordination.repositories.map(r => r.fullName),
          status: 'pending'
        },
        {
          id: 'deployment',
          name: 'Deployment',
          description: 'Deploy all releases',
          startDate: new Date(Date.now() + 14 * 24 * 60 * 60 * 1000),
          endDate: new Date(Date.now() + 21 * 24 * 60 * 60 * 1000),
          repositories: coordination.repositories.map(r => r.fullName),
          status: 'pending'
        }
      ],
      milestones: [
        {
          id: 'code_freeze',
          name: 'Code Freeze',
          date: new Date(Date.now() + 7 * 24 * 60 * 60 * 1000),
          type: 'code_freeze',
          status: 'pending',
          dependencies: []
        },
        {
          id: 'release_ready',
          name: 'Release Ready',
          date: new Date(Date.now() + 14 * 24 * 60 * 60 * 1000),
          type: 'release_ready',
          status: 'pending',
          dependencies: ['code_freeze']
        }
      ],
      criticalPath: ['preparation', 'testing', 'deployment']
    };

    return timeline;
  }

  private async executeSynchronizedRelease(coordination: VersionCoordination): Promise<boolean> {
    // Execute all releases simultaneously
    const promises = coordination.releases.map(release => this.deployRelease(release.id));
    const results = await Promise.all(promises);
    return results.every(result => result);
  }

  private async executeSequentialRelease(coordination: VersionCoordination): Promise<boolean> {
    // Execute releases one by one
    for (const release of coordination.releases) {
      const success = await this.deployRelease(release.id);
      if (!success) {
        return false;
      }
    }
    return true;
  }

  private async executeIndependentRelease(coordination: VersionCoordination): Promise<boolean> {
    // Execute releases independently (allow failures)
    const promises = coordination.releases.map(release => 
      this.deployRelease(release.id).catch(() => false)
    );
    await Promise.all(promises);
    return true; // Independent releases always "succeed"
  }

  private async executeGroupedRelease(coordination: VersionCoordination): Promise<boolean> {
    // Execute releases in groups based on dependencies
    // This would implement more sophisticated grouping logic
    return await this.executeSynchronizedRelease(coordination);
  }

  private async executeDeploymentStage(release: Release, stage: PipelineStage, pipeline: DeploymentPipeline): Promise<Deployment> {
    const deployment: Deployment = {
      id: `deploy_${Date.now()}_${Math.random().toString(36).substr(2, 9)}`,
      environment: stage.environment as any,
      status: 'in_progress',
      strategy: pipeline.strategy as any,
      startedAt: new Date(),
      deployedBy: release.author,
      healthChecks: [],
      rollbackAvailable: true,
      configuration: {
        replicas: 3,
        resources: {
          cpu: '500m',
          memory: '1Gi',
          storage: '10Gi'
        },
        environmentVariables: {},
        secrets: [],
        volumes: [],
        networking: {
          ports: [80, 443],
          domains: [],
          ingress: []
        },
        scaling: {
          minReplicas: 1,
          maxReplicas: 10,
          targetCpuUtilization: 70,
          targetMemoryUtilization: 80
        }
      }
    };

    try {
      // Simulate deployment execution
      await new Promise(resolve => setTimeout(resolve, 10000)); // 10 seconds

      deployment.status = 'success';
      deployment.completedAt = new Date();
      deployment.duration = deployment.completedAt.getTime() - deployment.startedAt.getTime();

      // Run health checks
      await this.runHealthChecks(deployment);

      this.emit('deployment-completed', deployment);

    } catch (error) {
      deployment.status = 'failure';
      deployment.completedAt = new Date();
      this.emit('deployment-failed', { deployment, error });
    }

    return deployment;
  }

  private async runHealthChecks(deployment: Deployment): Promise<void> {
    // Simulate running health checks
    deployment.healthChecks = [
      {
        id: 'api-health',
        name: 'API Health Check',
        url: 'https://api.example.com/health',
        method: 'GET',
        expectedStatus: 200,
        timeout: 5000,
        interval: 30000,
        retries: 3,
        status: 'passing',
        lastChecked: new Date(),
        response: {
          status: 200,
          responseTime: 150,
          body: '{"status": "healthy"}'
        }
      }
    ];
  }

  private async executeRollbackStep(release: Release, step: RollbackStep): Promise<void> {
    this.emit('rollback-step-started', { release, step });

    try {
      // Simulate step execution
      await new Promise(resolve => setTimeout(resolve, step.timeout / 10));
      
      this.emit('rollback-step-completed', { release, step });

    } catch (error) {
      this.emit('rollback-step-failed', { release, step, error });
      throw error;
    }
  }

  private async executeValidationStep(validation: ValidationStep): Promise<boolean> {
    try {
      // Simulate validation execution
      await new Promise(resolve => setTimeout(resolve, 1000));
      return true;
    } catch (error) {
      return false;
    }
  }

  private calculateAverageReleaseTime(releases: Release[]): number {
    const publishedReleases = releases.filter(r => r.publishedAt);
    if (publishedReleases.length === 0) return 0;

    const totalTime = publishedReleases.reduce((sum, release) => {
      return sum + (release.publishedAt!.getTime() - release.createdAt.getTime());
    }, 0);

    return totalTime / publishedReleases.length;
  }

  private calculateDeploymentFrequency(releases: Release[]): number {
    // Calculate deployments per day
    const publishedReleases = releases.filter(r => r.status === 'published');
    const timeSpan = Date.now() - Math.min(...releases.map(r => r.createdAt.getTime()));
    const days = timeSpan / (24 * 60 * 60 * 1000);
    
    return publishedReleases.length / Math.max(days, 1);
  }

  private calculateLeadTime(releases: Release[]): number {
    // Average time from first commit to deployment
    return 7 * 24 * 60 * 60 * 1000; // 7 days (placeholder)
  }

  private calculateMTTR(releases: Release[]): number {
    // Mean Time To Recovery
    return 4 * 60 * 60 * 1000; // 4 hours (placeholder)
  }

  private calculateChangeFailureRate(releases: Release[]): number {
    const totalReleases = releases.length;
    const failedReleases = releases.filter(r => r.status === 'failed').length;
    
    return totalReleases > 0 ? failedReleases / totalReleases : 0;
  }

  private calculateRollbackRate(releases: Release[]): number {
    const totalDeployments = releases.reduce((sum, r) => sum + r.deployments.length, 0);
    const rollbacks = releases.filter(r => r.status === 'failed').length;
    
    return totalDeployments > 0 ? rollbacks / totalDeployments : 0;
  }

  private groupReleasesByType(releases: Release[]): Record<string, number> {
    return releases.reduce((groups, release) => {
      groups[release.releaseType] = (groups[release.releaseType] || 0) + 1;
      return groups;
    }, {} as Record<string, number>);
  }

  private getTopContributors(releases: Release[]): { contributor: string; contributions: number }[] {
    const contributorCounts = new Map<string, number>();
    
    releases.forEach(release => {
      release.changelog.contributors.forEach(contributor => {
        const count = contributorCounts.get(contributor.username) || 0;
        contributorCounts.set(contributor.username, count + 1);
      });
    });

    return Array.from(contributorCounts.entries())
      .map(([contributor, contributions]) => ({ contributor, contributions }))
      .sort((a, b) => b.contributions - a.contributions)
      .slice(0, 10);
  }

  private calculateReleaseVelocity(releases: Release[]): number {
    // Number of releases per month
    const monthlyReleases = releases.length / 12; // Assuming 1 year of data
    return monthlyReleases;
  }

  // Event Handlers
  private handleReleaseCreated(release: Release): void {
    // Update metrics
    this.updateMetrics('releases_created', 1);
  }

  private handleDeploymentStarted(deployment: Deployment): void {
    // Handle deployment start
  }

  private handleDeploymentCompleted(deployment: Deployment): void {
    // Handle deployment completion
    this.updateMetrics('deployments_completed', 1);
  }

  private handleHealthCheckFailed(event: { deployment: Deployment; healthCheck: HealthCheck }): void {
    // Handle health check failure - potentially trigger rollback
    if (this.config.rollbackConfig.automaticRollback) {
      // Logic to determine if rollback should be triggered
    }
  }

  private handleRollbackTriggered(event: { release: Release; rollbackPlan: RollbackPlan; reason: string }): void {
    // Handle rollback trigger
    this.updateMetrics('rollbacks_triggered', 1);
  }

  private updateMetrics(metric: string, value: number): void {
    const current = this.performanceMetrics.get(metric) || 0;
    this.performanceMetrics.set(metric, current + value);
  }
}