/**
 * Task orchestrator for complex workflow management
 * Handles workflow execution with multiple strategies and dependency management
 */

import { EventEmitter } from 'node:events';
import { TaskDefinition, TaskResult, TaskStatus, AgentState, TaskError, TaskPriority, TaskId } from "../swarm/types.ts";
import { ILogger } from "../core/logger.ts";
import { IEventBus } from "../core/event-bus.ts";
import { BackgroundExecutor } from "./background-executor.ts";
import { HiveOrchestrator } from "./hive-orchestrator.ts";
import { LoadBalancer } from "./load-balancer.ts";
import { generateId } from "../utils/helpers.ts";

export interface TaskOrchestratorConfig {
  maxConcurrentWorkflows: number;
  maxWorkflowDepth: number;
  defaultTimeout: number;
  retryAttempts: number;
  enableCheckpointing: boolean;
  checkpointInterval: number;
  enableRecovery: boolean;
  enableMetrics: boolean;
  workflowStrategies: WorkflowStrategy[];
  dependencyResolution: DependencyResolutionStrategy;
}

export type WorkflowStrategy = 
  | 'sequential'
  | 'parallel'
  | 'adaptive'
  | 'consensus'
  | 'pipeline'
  | 'conditional'
  | 'loop'
  | 'fork-join'
  | 'map-reduce'
  | 'event-driven';

export type DependencyResolutionStrategy = 
  | 'strict'
  | 'optimistic'
  | 'lazy'
  | 'predictive';

export interface WorkflowDefinition {
  id: string;
  name: string;
  description: string;
  strategy: WorkflowStrategy;
  tasks: WorkflowTask[];
  dependencies: WorkflowDependency[];
  conditions: WorkflowCondition[];
  loops: WorkflowLoop[];
  variables: Map<string, any>;
  timeout: number;
  retryPolicy: RetryPolicy;
  checkpoints: WorkflowCheckpoint[];
  metadata: Record<string, any>;
  createdAt: Date;
  updatedAt: Date;
}

export interface WorkflowTask {
  id: string;
  workflowId: string;
  name: string;
  type: 'atomic' | 'composite' | 'conditional' | 'loop' | 'fork' | 'join';
  taskDefinition: TaskDefinition;
  dependencies: string[];
  conditions: string[];
  timeout: number;
  retryPolicy: RetryPolicy;
  assignedAgent?: string;
  status: TaskStatus;
  result?: TaskResult;
  error?: TaskError;
  startTime?: Date;
  endTime?: Date;
  executionTime?: number;
  metadata: Record<string, any>;
  createdAt: Date;
  updatedAt: Date;
}

export interface WorkflowDependency {
  id: string;
  fromTaskId: string;
  toTaskId: string;
  type: 'data' | 'control' | 'resource' | 'temporal';
  condition?: string;
  weight: number;
  metadata: Record<string, any>;
}

export interface WorkflowCondition {
  id: string;
  name: string;
  expression: string;
  type: 'pre' | 'post' | 'guard' | 'invariant';
  taskIds: string[];
  metadata: Record<string, any>;
}

export interface WorkflowLoop {
  id: string;
  name: string;
  type: 'while' | 'for' | 'foreach' | 'until';
  condition: string;
  taskIds: string[];
  maxIterations: number;
  currentIteration: number;
  metadata: Record<string, any>;
}

export interface RetryPolicy {
  maxAttempts: number;
  backoffStrategy: 'linear' | 'exponential' | 'fixed';
  baseDelay: number;
  maxDelay: number;
  jitter: boolean;
  conditions: string[];
}

export interface WorkflowCheckpoint {
  id: string;
  workflowId: string;
  taskId: string;
  state: WorkflowState;
  timestamp: Date;
  metadata: Record<string, any>;
}

export interface WorkflowState {
  workflowId: string;
  status: 'pending' | 'running' | 'completed' | 'failed' | 'cancelled' | 'paused';
  completedTasks: string[];
  failedTasks: string[];
  runningTasks: string[];
  variables: Map<string, any>;
  checkpoints: WorkflowCheckpoint[];
  startTime?: Date;
  endTime?: Date;
  executionTime?: number;
  metadata: Record<string, any>;
}

export interface WorkflowExecution {
  id: string;
  workflowId: string;
  state: WorkflowState;
  strategy: WorkflowStrategy;
  progress: WorkflowProgress;
  metrics: WorkflowMetrics;
  createdAt: Date;
  updatedAt: Date;
}

export interface WorkflowProgress {
  totalTasks: number;
  completedTasks: number;
  failedTasks: number;
  runningTasks: number;
  pendingTasks: number;
  percentage: number;
  estimatedTimeRemaining: number;
}

export interface WorkflowMetrics {
  executionTime: number;
  throughput: number;
  successRate: number;
  errorRate: number;
  resourceUtilization: number;
  parallelism: number;
  checkpointCount: number;
  recoveryCount: number;
}

export interface TaskOrchestratorMetrics {
  totalWorkflows: number;
  activeWorkflows: number;
  completedWorkflows: number;
  failedWorkflows: number;
  averageExecutionTime: number;
  throughput: number;
  successRate: number;
  strategyEffectiveness: Map<WorkflowStrategy, number>;
  resourceUtilization: number;
  checkpointEfficiency: number;
}

export class TaskOrchestrator extends EventEmitter {
  private workflows = new Map<string, WorkflowDefinition>();
  private executions = new Map<string, WorkflowExecution>();
  private activeExecutions = new Set<string>();
  private checkpointTimer?: NodeJS.Timeout;
  private metrics: TaskOrchestratorMetrics;
  private isShuttingDown = false;

  constructor(
    private config: TaskOrchestratorConfig,
    private logger: ILogger,
    private eventBus: IEventBus,
    private backgroundExecutor: BackgroundExecutor,
    private hiveOrchestrator: HiveOrchestrator,
    private loadBalancer: LoadBalancer
  ) {
    super();
    this.metrics = this.initializeMetrics();
    this.setupEventHandlers();
  }

  private initializeMetrics(): TaskOrchestratorMetrics {
    return {
      totalWorkflows: 0,
      activeWorkflows: 0,
      completedWorkflows: 0,
      failedWorkflows: 0,
      averageExecutionTime: 0,
      throughput: 0,
      successRate: 0,
      strategyEffectiveness: new Map(),
      resourceUtilization: 0,
      checkpointEfficiency: 0
    };
  }

  private setupEventHandlers(): void {
    this.eventBus.on('system:shutdown', () => this.shutdown());
    this.eventBus.on('task:completed', (result: TaskResult) => this.handleTaskCompletion(result));
    this.eventBus.on('task:failed', (error: TaskError) => this.handleTaskFailure(error));
    this.eventBus.on('workflow:checkpoint', (checkpoint: WorkflowCheckpoint) => this.handleCheckpoint(checkpoint));
  }

  async initialize(): Promise<void> {
    this.logger.info('Initializing TaskOrchestrator');

    // Start checkpoint timer if enabled
    if (this.config.enableCheckpointing) {
      this.checkpointTimer = setInterval(
        () => this.performCheckpointing(),
        this.config.checkpointInterval
      );
    }

    this.logger.info('TaskOrchestrator initialized successfully');
  }

  async shutdown(): Promise<void> {
    this.logger.info('Shutting down TaskOrchestrator');
    this.isShuttingDown = true;

    // Clear timers
    if (this.checkpointTimer) clearInterval(this.checkpointTimer);

    // Cancel all active executions
    const activeExecutionIds = Array.from(this.activeExecutions);
    await Promise.all(activeExecutionIds.map(id => this.cancelExecution(id)));

    this.logger.info('TaskOrchestrator shutdown complete');
  }

  /**
   * Create a new workflow definition
   */
  async createWorkflow(definition: Omit<WorkflowDefinition, 'id' | 'createdAt' | 'updatedAt'>): Promise<string> {
    if (this.isShuttingDown) {
      throw new Error('TaskOrchestrator is shutting down');
    }

    const workflow: WorkflowDefinition = {
      ...definition,
      id: generateId(),
      createdAt: new Date(),
      updatedAt: new Date()
    };

    // Validate workflow
    await this.validateWorkflow(workflow);

    this.workflows.set(workflow.id, workflow);
    this.metrics.totalWorkflows++;

    this.logger.info('Workflow created', { workflowId: workflow.id, name: workflow.name });
    this.emit('workflow:created', workflow);

    return workflow.id;
  }

  /**
   * Execute a workflow
   */
  async executeWorkflow(workflowId: string, initialVariables?: Map<string, any>): Promise<string> {
    if (this.isShuttingDown) {
      throw new Error('TaskOrchestrator is shutting down');
    }

    if (this.activeExecutions.size >= this.config.maxConcurrentWorkflows) {
      throw new Error('Maximum concurrent workflows reached');
    }

    const workflow = this.workflows.get(workflowId);
    if (!workflow) {
      throw new Error(`Workflow not found: ${workflowId}`);
    }

    const executionId = generateId();
    const execution: WorkflowExecution = {
      id: executionId,
      workflowId,
      state: {
        workflowId,
        status: 'pending',
        completedTasks: [],
        failedTasks: [],
        runningTasks: [],
        variables: initialVariables || new Map(),
        checkpoints: [],
        metadata: {}
      },
      strategy: workflow.strategy,
      progress: {
        totalTasks: workflow.tasks.length,
        completedTasks: 0,
        failedTasks: 0,
        runningTasks: 0,
        pendingTasks: workflow.tasks.length,
        percentage: 0,
        estimatedTimeRemaining: 0
      },
      metrics: {
        executionTime: 0,
        throughput: 0,
        successRate: 0,
        errorRate: 0,
        resourceUtilization: 0,
        parallelism: 0,
        checkpointCount: 0,
        recoveryCount: 0
      },
      createdAt: new Date(),
      updatedAt: new Date()
    };

    this.executions.set(executionId, execution);
    this.activeExecutions.add(executionId);
    this.metrics.activeWorkflows++;

    this.logger.info('Starting workflow execution', { workflowId, executionId, strategy: workflow.strategy });
    this.emit('workflow:started', execution);

    try {
      await this.executeWorkflowStrategy(execution, workflow);
      return executionId;
    } catch (error) {
      this.activeExecutions.delete(executionId);
      this.metrics.activeWorkflows--;
      this.metrics.failedWorkflows++;
      throw error;
    }
  }

  /**
   * Cancel a workflow execution
   */
  async cancelExecution(executionId: string): Promise<boolean> {
    const execution = this.executions.get(executionId);
    if (!execution) {
      return false;
    }

    execution.state.status = 'cancelled';
    execution.state.endTime = new Date();
    execution.updatedAt = new Date();

    // Cancel all running tasks
    for (const taskId of execution.state.runningTasks) {
      await this.cancelTask(taskId);
    }

    this.activeExecutions.delete(executionId);
    this.metrics.activeWorkflows--;

    this.logger.info('Workflow execution cancelled', { executionId });
    this.emit('workflow:cancelled', execution);

    return true;
  }

  /**
   * Pause a workflow execution
   */
  async pauseExecution(executionId: string): Promise<boolean> {
    const execution = this.executions.get(executionId);
    if (!execution || execution.state.status !== 'running') {
      return false;
    }

    execution.state.status = 'paused';
    execution.updatedAt = new Date();

    this.logger.info('Workflow execution paused', { executionId });
    this.emit('workflow:paused', execution);

    return true;
  }

  /**
   * Resume a workflow execution
   */
  async resumeExecution(executionId: string): Promise<boolean> {
    const execution = this.executions.get(executionId);
    if (!execution || execution.state.status !== 'paused') {
      return false;
    }

    execution.state.status = 'running';
    execution.updatedAt = new Date();

    this.logger.info('Workflow execution resumed', { executionId });
    this.emit('workflow:resumed', execution);

    // Continue execution
    const workflow = this.workflows.get(execution.workflowId);
    if (workflow) {
      await this.executeWorkflowStrategy(execution, workflow);
    }

    return true;
  }

  /**
   * Get workflow execution status
   */
  getExecution(executionId: string): WorkflowExecution | undefined {
    return this.executions.get(executionId);
  }

  /**
   * Get all workflow executions
   */
  getAllExecutions(): WorkflowExecution[] {
    return Array.from(this.executions.values());
  }

  /**
   * Get orchestrator metrics
   */
  getMetrics(): TaskOrchestratorMetrics {
    this.updateMetrics();
    return { ...this.metrics };
  }

  // Private workflow execution methods
  private async executeWorkflowStrategy(execution: WorkflowExecution, workflow: WorkflowDefinition): Promise<void> {
    execution.state.status = 'running';
    execution.state.startTime = new Date();
    execution.updatedAt = new Date();

    try {
      switch (workflow.strategy) {
        case 'sequential':
          await this.executeSequential(execution, workflow);
          break;
        case 'parallel':
          await this.executeParallel(execution, workflow);
          break;
        case 'adaptive':
          await this.executeAdaptive(execution, workflow);
          break;
        case 'consensus':
          await this.executeConsensus(execution, workflow);
          break;
        case 'pipeline':
          await this.executePipeline(execution, workflow);
          break;
        case 'conditional':
          await this.executeConditional(execution, workflow);
          break;
        case 'loop':
          await this.executeLoop(execution, workflow);
          break;
        case 'fork-join':
          await this.executeForkJoin(execution, workflow);
          break;
        case 'map-reduce':
          await this.executeMapReduce(execution, workflow);
          break;
        case 'event-driven':
          await this.executeEventDriven(execution, workflow);
          break;
        default:
          throw new Error(`Unknown workflow strategy: ${workflow.strategy}`);
      }

      execution.state.status = 'completed';
      execution.state.endTime = new Date();
      execution.metrics.executionTime = execution.state.endTime.getTime() - (execution.state.startTime?.getTime() || 0);
      
      this.activeExecutions.delete(execution.id);
      this.metrics.activeWorkflows--;
      this.metrics.completedWorkflows++;

      this.logger.info('Workflow execution completed', { executionId: execution.id, duration: execution.metrics.executionTime });
      this.emit('workflow:completed', execution);

    } catch (error) {
      execution.state.status = 'failed';
      execution.state.endTime = new Date();
      execution.metrics.executionTime = execution.state.endTime.getTime() - (execution.state.startTime?.getTime() || 0);
      
      this.activeExecutions.delete(execution.id);
      this.metrics.activeWorkflows--;
      this.metrics.failedWorkflows++;

      this.logger.error('Workflow execution failed', { executionId: execution.id, error });
      this.emit('workflow:failed', execution, error);
      
      throw error;
    }
  }

  private async executeSequential(execution: WorkflowExecution, workflow: WorkflowDefinition): Promise<void> {
    const sortedTasks = this.topologicalSort(workflow.tasks, workflow.dependencies);
    
    for (const task of sortedTasks) {
      if (execution.state.status !== 'running') {
        break;
      }

      await this.executeTask(execution, task);
    }
  }

  private async executeParallel(execution: WorkflowExecution, workflow: WorkflowDefinition): Promise<void> {
    const independentTasks = this.findIndependentTasks(workflow.tasks, workflow.dependencies);
    
    // Execute all independent tasks in parallel
    await Promise.all(independentTasks.map(task => this.executeTask(execution, task)));
  }

  private async executeAdaptive(execution: WorkflowExecution, workflow: WorkflowDefinition): Promise<void> {
    // Analyze workflow characteristics and choose best strategy
    const characteristics = this.analyzeWorkflowCharacteristics(workflow);
    
    if (characteristics.parallelizable) {
      await this.executeParallel(execution, workflow);
    } else if (characteristics.hasConditions) {
      await this.executeConditional(execution, workflow);
    } else {
      await this.executeSequential(execution, workflow);
    }
  }

  private async executeConsensus(execution: WorkflowExecution, workflow: WorkflowDefinition): Promise<void> {
    // Use hive orchestrator for consensus-based execution
    const decompositionId = await this.hiveOrchestrator.decomposeTask(
      this.workflowToTask(workflow),
      'consensus-based'
    );

    // Wait for completion
    await this.waitForDecompositionCompletion(decompositionId);
  }

  private async executePipeline(execution: WorkflowExecution, workflow: WorkflowDefinition): Promise<void> {
    // Execute tasks in pipeline stages
    const stages = this.identifyPipelineStages(workflow);
    
    for (const stage of stages) {
      await Promise.all(stage.map(task => this.executeTask(execution, task)));
    }
  }

  private async executeConditional(execution: WorkflowExecution, workflow: WorkflowDefinition): Promise<void> {
    for (const task of workflow.tasks) {
      if (execution.state.status !== 'running') {
        break;
      }

      // Check conditions
      if (await this.evaluateConditions(task.conditions, execution.state.variables)) {
        await this.executeTask(execution, task);
      }
    }
  }

  private async executeLoop(execution: WorkflowExecution, workflow: WorkflowDefinition): Promise<void> {
    for (const loop of workflow.loops) {
      let iteration = 0;
      
      while (iteration < loop.maxIterations) {
        if (execution.state.status !== 'running') {
          break;
        }

        // Evaluate loop condition
        if (!await this.evaluateCondition(loop.condition, execution.state.variables)) {
          break;
        }

        // Execute loop tasks
        const loopTasks = workflow.tasks.filter(task => loop.taskIds.includes(task.id));
        for (const task of loopTasks) {
          await this.executeTask(execution, task);
        }

        iteration++;
      }
    }
  }

  private async executeForkJoin(execution: WorkflowExecution, workflow: WorkflowDefinition): Promise<void> {
    const forkTasks = workflow.tasks.filter(task => task.type === 'fork');
    const joinTasks = workflow.tasks.filter(task => task.type === 'join');
    
    // Execute fork tasks
    for (const forkTask of forkTasks) {
      await this.executeTask(execution, forkTask);
    }

    // Execute join tasks
    for (const joinTask of joinTasks) {
      await this.executeTask(execution, joinTask);
    }
  }

  private async executeMapReduce(execution: WorkflowExecution, workflow: WorkflowDefinition): Promise<void> {
    // Identify map and reduce tasks
    const mapTasks = workflow.tasks.filter(task => task.metadata.type === 'map');
    const reduceTasks = workflow.tasks.filter(task => task.metadata.type === 'reduce');
    
    // Execute map phase
    await Promise.all(mapTasks.map(task => this.executeTask(execution, task)));
    
    // Execute reduce phase
    await Promise.all(reduceTasks.map(task => this.executeTask(execution, task)));
  }

  private async executeEventDriven(execution: WorkflowExecution, workflow: WorkflowDefinition): Promise<void> {
    // Set up event listeners for workflow tasks
    const eventTasks = workflow.tasks.filter(task => task.metadata.trigger === 'event');
    
    for (const task of eventTasks) {
      this.eventBus.on(task.metadata.event, async () => {
        await this.executeTask(execution, task);
      });
    }
  }

  private async executeTask(execution: WorkflowExecution, task: WorkflowTask): Promise<void> {
    // Check dependencies
    if (!await this.checkDependencies(task, execution)) {
      return;
    }

    task.status = 'running';
    task.startTime = new Date();
    execution.state.runningTasks.push(task.id);
    execution.progress.runningTasks++;

    this.logger.info('Executing workflow task', { executionId: execution.id, taskId: task.id });

    try {
      // Select agent for task
      const decision = await this.loadBalancer.selectAgent(task.taskDefinition);
      task.assignedAgent = decision.selectedAgent;

      // Execute task based on type
      let result: TaskResult;
      
      switch (task.type) {
        case 'atomic':
          result = await this.executeAtomicTask(task);
          break;
        case 'composite':
          result = await this.executeCompositeTask(task);
          break;
        case 'conditional':
          result = await this.executeConditionalTask(task, execution);
          break;
        case 'loop':
          result = await this.executeLoopTask(task, execution);
          break;
        case 'fork':
          result = await this.executeForkTask(task, execution);
          break;
        case 'join':
          result = await this.executeJoinTask(task, execution);
          break;
        default:
          throw new Error(`Unknown task type: ${task.type}`);
      }

      task.status = 'completed';
      task.result = result;
      task.endTime = new Date();
      task.executionTime = task.endTime.getTime() - (task.startTime?.getTime() || 0);

      execution.state.runningTasks = execution.state.runningTasks.filter(id => id !== task.id);
      execution.state.completedTasks.push(task.id);
      execution.progress.runningTasks--;
      execution.progress.completedTasks++;

      this.logger.info('Workflow task completed', { executionId: execution.id, taskId: task.id });
      this.emit('task:completed', task);

    } catch (error) {
      task.status = 'failed';
      task.error = {
        type: 'task_execution_error',
        message: error instanceof Error ? error.message : String(error),
        stack: error instanceof Error ? error.stack : undefined,
        context: { taskId: task.id, workflowId: task.workflowId },
        recoverable: true,
        retryable: true
      };
      task.endTime = new Date();
      task.executionTime = task.endTime.getTime() - (task.startTime?.getTime() || 0);

      execution.state.runningTasks = execution.state.runningTasks.filter(id => id !== task.id);
      execution.state.failedTasks.push(task.id);
      execution.progress.runningTasks--;
      execution.progress.failedTasks++;

      this.logger.error('Workflow task failed', { executionId: execution.id, taskId: task.id, error });
      this.emit('task:failed', task, error);

      // Handle retry logic
      if (await this.shouldRetryTask(task)) {
        await this.retryTask(execution, task);
      } else {
        throw error;
      }
    }
  }

  // Task execution methods
  private async executeAtomicTask(task: WorkflowTask): Promise<TaskResult> {
    // Submit to background executor
    const taskId = await this.backgroundExecutor.submitTask({
      type: 'agent-task',
      command: 'claude',
      args: ['-p', task.taskDefinition.description || ''],
      options: {
        timeout: task.timeout,
        metadata: {
          workflowTaskId: task.id,
          agentId: task.assignedAgent
        }
      },
      priority: this.convertPriorityToNumber(task.taskDefinition.priority)
    });

    // Wait for completion
    return await this.waitForTaskCompletion(taskId);
  }

  private async executeCompositeTask(task: WorkflowTask): Promise<TaskResult> {
    // Decompose using hive orchestrator
    const decompositionId = await this.hiveOrchestrator.decomposeTask(task.taskDefinition);
    
    // Wait for completion
    const decomposition = await this.waitForDecompositionCompletion(decompositionId);
    
    return {
      output: decomposition,
      artifacts: {},
      metadata: { 
        taskId: task.id,
        agentId: task.assignedAgent || '',
        status: 'completed',
        timestamp: new Date()
      },
      quality: 0.8,
      completeness: 1.0,
      accuracy: 0.9,
      executionTime: task.executionTime || 0,
      resourcesUsed: {},
      validated: false
    };
  }

  private async executeConditionalTask(task: WorkflowTask, execution: WorkflowExecution): Promise<TaskResult> {
    // Evaluate conditions
    const conditionsMet = await this.evaluateConditions(task.conditions, execution.state.variables);
    
    if (conditionsMet) {
      return await this.executeAtomicTask(task);
    } else {
      return {
        output: 'Conditions not met',
        artifacts: {},
        metadata: { 
          taskId: task.id,
          agentId: task.assignedAgent || '',
          status: 'skipped',
          timestamp: new Date()
        },
        quality: 0.8,
        completeness: 1.0,
        accuracy: 0.9,
        executionTime: 0,
        resourcesUsed: {},
        validated: false
      };
    }
  }

  private async executeLoopTask(task: WorkflowTask, execution: WorkflowExecution): Promise<TaskResult> {
    // Loop execution - iterate based on conditions
    const loop = execution.state.variables.get('loop') || {};
    const results = [];
    let iteration = 0;
    
    while (iteration < (loop.maxIterations || 10)) {
      if (loop.condition && !(await this.evaluateCondition(loop.condition, execution.state.variables))) {
        break;
      }

      const result = await this.executeAtomicTask(task);
      results.push(result);
      iteration++;
    }

    return {
      // Result data
      output: results,
      artifacts: {},
      metadata: { iterations: iteration },
      
      // Quality metrics
      quality: 0.8,
      completeness: 1.0,
      accuracy: 0.9,
      
      // Performance metrics
      executionTime: task.executionTime || 0,
      resourcesUsed: {},
      
      // Validation
      validated: true,
      validationResults: null,
      
      // Follow-up
      recommendations: [],
      nextSteps: []
    };
  }

  private async executeForkTask(task: WorkflowTask, execution: WorkflowExecution): Promise<TaskResult> {
    // Fork execution - create parallel branches
    const branches = task.metadata.branches || [];
    const results = await Promise.all(branches.map((branch: any) => this.executeBranch(branch, execution)));

    return {
      // Result data
      output: results,
      artifacts: {},
      metadata: { branches: branches.length },
      
      // Quality metrics
      quality: 0.8,
      completeness: 1.0,
      accuracy: 0.9,
      
      // Performance metrics
      executionTime: task.executionTime || 0,
      resourcesUsed: {},
      
      // Validation
      validated: true,
      validationResults: null,
      
      // Follow-up
      recommendations: [],
      nextSteps: []
    };
  }

  private async executeJoinTask(task: WorkflowTask, execution: WorkflowExecution): Promise<TaskResult> {
    // Join execution - wait for all branches to complete
    const branchResults = task.metadata.branchResults || [];
    
    return {
      // Result data
      output: branchResults,
      artifacts: {},
      metadata: { joinedBranches: branchResults.length },
      
      // Quality metrics
      quality: 0.8,
      completeness: 1.0,
      accuracy: 0.9,
      
      // Performance metrics
      executionTime: task.executionTime || 0,
      resourcesUsed: {},
      
      // Validation
      validated: true,
      validationResults: null,
      
      // Follow-up
      recommendations: [],
      nextSteps: []
    };
  }

  // Helper methods
  private async validateWorkflow(workflow: WorkflowDefinition): Promise<void> {
    // Validate workflow structure
    if (!workflow.tasks || workflow.tasks.length === 0) {
      throw new Error('Workflow must have at least one task');
    }

    // Check for circular dependencies
    if (this.hasCyclicDependencies(workflow.tasks, workflow.dependencies)) {
      throw new Error('Workflow contains circular dependencies');
    }

    // Validate task definitions
    for (const task of workflow.tasks) {
      if (!task.taskDefinition) {
        throw new Error(`Task ${task.id} missing task definition`);
      }
    }
  }

  private hasCyclicDependencies(tasks: WorkflowTask[], dependencies: WorkflowDependency[]): boolean {
    const graph = new Map<string, string[]>();
    
    // Build adjacency list
    for (const task of tasks) {
      graph.set(task.id, []);
    }
    
    for (const dep of dependencies) {
      graph.get(dep.fromTaskId)?.push(dep.toTaskId);
    }

    // DFS to detect cycles
    const visited = new Set<string>();
    const recursionStack = new Set<string>();

    const hasCycle = (taskId: string): boolean => {
      visited.add(taskId);
      recursionStack.add(taskId);

      const neighbors = graph.get(taskId) || [];
      for (const neighbor of neighbors) {
        if (!visited.has(neighbor)) {
          if (hasCycle(neighbor)) {
            return true;
          }
        } else if (recursionStack.has(neighbor)) {
          return true;
        }
      }

      recursionStack.delete(taskId);
      return false;
    };

    for (const taskId of graph.keys()) {
      if (!visited.has(taskId)) {
        if (hasCycle(taskId)) {
          return true;
        }
      }
    }

    return false;
  }

  private topologicalSort(tasks: WorkflowTask[], dependencies: WorkflowDependency[]): WorkflowTask[] {
    const graph = new Map<string, string[]>();
    const inDegree = new Map<string, number>();

    // Initialize
    for (const task of tasks) {
      graph.set(task.id, []);
      inDegree.set(task.id, 0);
    }

    // Build graph
    for (const dep of dependencies) {
      graph.get(dep.fromTaskId)?.push(dep.toTaskId);
      inDegree.set(dep.toTaskId, (inDegree.get(dep.toTaskId) || 0) + 1);
    }

    // Kahn's algorithm
    const queue: string[] = [];
    const result: WorkflowTask[] = [];

    for (const [taskId, degree] of inDegree) {
      if (degree === 0) {
        queue.push(taskId);
      }
    }

    while (queue.length > 0) {
      const taskId = queue.shift()!;
      const task = tasks.find(t => t.id === taskId)!;
      result.push(task);

      const neighbors = graph.get(taskId) || [];
      for (const neighbor of neighbors) {
        inDegree.set(neighbor, (inDegree.get(neighbor) || 0) - 1);
        if (inDegree.get(neighbor) === 0) {
          queue.push(neighbor);
        }
      }
    }

    return result;
  }

  private findIndependentTasks(tasks: WorkflowTask[], dependencies: WorkflowDependency[]): WorkflowTask[] {
    const dependentTasks = new Set<string>();
    
    for (const dep of dependencies) {
      dependentTasks.add(dep.toTaskId);
    }

    return tasks.filter(task => !dependentTasks.has(task.id));
  }

  private analyzeWorkflowCharacteristics(workflow: WorkflowDefinition): any {
    return {
      parallelizable: workflow.dependencies.length < workflow.tasks.length,
      hasConditions: workflow.conditions.length > 0,
      hasLoops: workflow.loops.length > 0,
      complexity: workflow.tasks.length
    };
  }

  private identifyPipelineStages(workflow: WorkflowDefinition): WorkflowTask[][] {
    // Simplified pipeline stage identification
    const stages: WorkflowTask[][] = [];
    const sortedTasks = this.topologicalSort(workflow.tasks, workflow.dependencies);
    
    let currentStage: WorkflowTask[] = [];
    for (const task of sortedTasks) {
      if (currentStage.length === 0 || this.canRunInParallel(task, currentStage[0], workflow.dependencies)) {
        currentStage.push(task);
      } else {
        stages.push(currentStage);
        currentStage = [task];
      }
    }
    
    if (currentStage.length > 0) {
      stages.push(currentStage);
    }

    return stages;
  }

  private canRunInParallel(task1: WorkflowTask, task2: WorkflowTask, dependencies: WorkflowDependency[]): boolean {
    // Check if tasks can run in parallel (no direct dependency)
    return !dependencies.some(dep => 
      (dep.fromTaskId === task1.id && dep.toTaskId === task2.id) ||
      (dep.fromTaskId === task2.id && dep.toTaskId === task1.id)
    );
  }

  private async checkDependencies(task: WorkflowTask, execution: WorkflowExecution): Promise<boolean> {
    // Check if all dependencies are satisfied
    return task.dependencies.every(depId => execution.state.completedTasks.includes(depId));
  }

  private async evaluateConditions(conditions: string[], variables: Map<string, any>): Promise<boolean> {
    // Simplified condition evaluation
    return conditions.length === 0 || conditions.every(condition => this.evaluateCondition(condition, variables));
  }

  private async evaluateCondition(condition: string, variables: Map<string, any>): Promise<boolean> {
    // Simplified condition evaluation
    // In a real implementation, this would parse and evaluate the condition expression
    return true;
  }

  private workflowToTask(workflow: WorkflowDefinition): TaskDefinition {
    // Create proper TaskId object
    const taskId: TaskId = {
      id: workflow.id,
      swarmId: 'default-swarm',
      sequence: 0,
      priority: 0
    };

    // Convert to TaskPriority enum
    const priority: TaskPriority = 'normal';

    return {
      id: taskId,
      type: 'coordination',
      name: workflow.name,
      description: workflow.description,
      requirements: {
        capabilities: [],
        tools: [],
        permissions: []
      },
      constraints: {
        dependencies: [],
        dependents: [],
        conflicts: []
      },
      priority: priority,
      input: {},
      instructions: workflow.description,
      context: workflow.metadata,
      status: 'created',
      createdAt: new Date(),
      updatedAt: new Date(),
      attempts: [],
      statusHistory: []
    };
  }

  private async waitForDecompositionCompletion(decompositionId: string): Promise<any> {
    return new Promise((resolve, reject) => {
      const checkCompletion = () => {
        const decomposition = this.hiveOrchestrator.getDecomposition(decompositionId);
        if (!decomposition) {
          reject(new Error('Decomposition not found'));
          return;
        }

        const allCompleted = decomposition.subtasks.every(st => st.status === 'completed');
        const anyFailed = decomposition.subtasks.some(st => st.status === 'failed');

        if (allCompleted) {
          resolve(decomposition);
        } else if (anyFailed) {
          reject(new Error('Decomposition failed'));
        } else {
          setTimeout(checkCompletion, 100);
        }
      };

      checkCompletion();
    });
  }

  private async waitForTaskCompletion(taskId: string): Promise<TaskResult> {
    return new Promise((resolve, reject) => {
      const checkTask = () => {
        const task = this.backgroundExecutor.getTask(taskId);
        if (!task) {
          reject(new Error('Task not found'));
          return;
        }

        if (task.status === 'completed') {
          resolve({
            // Result data
            output: task.result,
            artifacts: {},
            metadata: { taskId: task.id },
            
            // Quality metrics
            quality: 0.8,
            completeness: 1.0,
            accuracy: 0.9,
            
            // Performance metrics
            executionTime: task.executionTime || 0,
            resourcesUsed: {},
            
            // Validation
            validated: true,
            validationResults: null,
            
            // Follow-up
            recommendations: [],
            nextSteps: []
          });
        } else if (task.status === 'failed') {
          reject(new Error(task.error || 'Task failed'));
        } else {
          setTimeout(checkTask, 100);
        }
      };

      checkTask();
    });
  }

  private async shouldRetryTask(task: WorkflowTask): Promise<boolean> {
    // Implement retry logic based on retry policy
    return false; // Simplified
  }

  private async retryTask(execution: WorkflowExecution, task: WorkflowTask): Promise<void> {
    // Implement task retry logic
  }

  private async cancelTask(taskId: string): Promise<void> {
    // Cancel task execution
  }

  private async executeBranch(branch: any, execution: WorkflowExecution): Promise<any> {
    // Execute workflow branch
    return {};
  }

  private performCheckpointing(): void {
    if (!this.config.enableCheckpointing) return;

    for (const execution of this.executions.values()) {
      if (execution.state.status === 'running') {
        this.createCheckpoint(execution);
      }
    }
  }

  private createCheckpoint(execution: WorkflowExecution): void {
    const checkpoint: WorkflowCheckpoint = {
      id: generateId(),
      workflowId: execution.workflowId,
      taskId: execution.state.runningTasks[0] || '',
      state: { ...execution.state },
      timestamp: new Date(),
      metadata: {}
    };

    execution.state.checkpoints.push(checkpoint);
    execution.metrics.checkpointCount++;

    this.logger.info('Workflow checkpoint created', { executionId: execution.id, checkpointId: checkpoint.id });
  }

  private handleTaskCompletion(result: TaskResult): void {
    // Handle task completion events
  }

  private handleTaskFailure(error: TaskError): void {
    // Handle task failure events
  }

  private handleCheckpoint(checkpoint: WorkflowCheckpoint): void {
    // Handle checkpoint events
  }

  private convertPriorityToNumber(priority: TaskPriority): number {
    switch (priority) {
      case 'critical': return 5;
      case 'high': return 4;
      case 'normal': return 3;
      case 'low': return 2;
      case 'background': return 1;
      default: return 3;
    }
  }

  private updateMetrics(): void {
    // Update orchestrator metrics
    this.metrics.activeWorkflows = this.activeExecutions.size;
    
    const totalExecutions = this.executions.size;
    this.metrics.successRate = totalExecutions > 0 
      ? this.metrics.completedWorkflows / totalExecutions
      : 0;
  }
}