/**
 * Example: Deterministic State Machine Pipeline
 * 
 * Demonstrates how to use the deterministic state machine
 * and parallel execution engine for multi-agent workflows.
 */

import {
  DeterministicStateMachine,
  ParallelExecutionEngine,
  EventBus
} from '../pipeline-system';

async function stateMachineExample() {
  // Create event bus for coordination
  const eventBus = new EventBus();

  // Subscribe to events
  eventBus.subscribe('state:*', (event) => {
    console.log(`[Event] ${event.type}:`, event.data);
  });

  // Define state machine configuration
  const smConfig = {
    initialState: 'idle',
    states: {
      idle: {
        onEnter: async (context: any) => {
          console.log('Entering IDLE state');
          context.startTime = Date.now();
        },
        transitions: [
          {
            target: 'initializing',
            event: 'start',
            condition: (ctx: any) => ctx.config !== null
          }
        ]
      },
      initializing: {
        onEnter: async (context: any) => {
          console.log('Initializing...');
          // Simulate async initialization
          await new Promise(resolve => setTimeout(resolve, 100));
        },
        onExit: async (context: any) => {
          console.log('Initialization complete');
          context.initialized = true;
        },
        transitions: [
          { target: 'processing', event: 'initialized' }
        ]
      },
      processing: {
        onEnter: async (context: any) => {
          console.log('Processing started');
        },
        transitions: [
          { target: 'completed', event: 'done', condition: (ctx: any) => ctx.success },
          { target: 'error', event: 'error' }
        ]
      },
      completed: {
        onEnter: async (context: any) => {
          context.endTime = Date.now();
          console.log(`Completed in ${context.endTime - context.startTime}ms`);
        },
        final: true
      },
      error: {
        onEnter: async (context: any) => {
          console.error('Error state reached');
        },
        final: true
      }
    }
  };

  // Create state machine
  const stateMachine = new DeterministicStateMachine(smConfig);

  // Initialize with context
  const context = { config: { maxRetries: 3 }, success: true };

  // Start the state machine
  console.log('--- Starting State Machine ---');
  await stateMachine.start(context);
  console.log('Current state:', stateMachine.getState());

  // Trigger transitions
  console.log('\n--- Triggering Transitions ---');
  
  // Check if transition is valid
  if (stateMachine.canTransition('start')) {
    await stateMachine.transition('start', context);
    console.log('After start:', stateMachine.getState());
  }

  if (stateMachine.canTransition('initialized')) {
    await stateMachine.transition('initialized', context);
    console.log('After initialized:', stateMachine.getState());
  }

  if (stateMachine.canTransition('done')) {
    await stateMachine.transition('done', context);
    console.log('After done:', stateMachine.getState());
  }

  // Check if final state
  console.log('\nIs final state:', stateMachine.isFinalState());

  // Now demonstrate parallel execution
  console.log('\n--- Parallel Execution Engine ---');

  const executor = new ParallelExecutionEngine({
    maxConcurrency: 4,
    taskQueue: 'priority',
    timeout: 30000
  });

  // Define tasks
  const tasks = [
    { id: 'task-1', type: 'analyze', priority: 1, data: { target: 'module-a' } },
    { id: 'task-2', type: 'analyze', priority: 2, data: { target: 'module-b' } },
    { id: 'task-3', type: 'analyze', priority: 1, data: { target: 'module-c' } },
    { id: 'task-4', type: 'analyze', priority: 3, data: { target: 'module-d' } }
  ];

  // Execute in parallel with custom handler
  const results = await executor.executeAll(tasks, async (task) => {
    console.log(`Processing ${task.id}...`);
    await new Promise(resolve => setTimeout(resolve, 100));
    return { taskId: task.id, result: `Analyzed ${task.data.target}` };
  });

  console.log('\nResults:', results);

  // Get execution stats
  const stats = executor.getStats();
  console.log('Execution stats:', stats);

  // Cleanup
  executor.shutdown();
  eventBus.clearAllSubscriptions();

  console.log('\n--- Example Complete ---');
}

// Run the example
stateMachineExample().catch(console.error);