import { HookContext, HookExecutionResult } from './hook-registry';
import { Logger } from '../../utils/logger';

const logger = new Logger('ProcessingHooks');

/**
 * @module ProcessingHooks
 * @description Provides a collection of common pre/post processing, error, performance, and security hook handlers.
 */

/**
 * Pre-execution hook: Validates input data.
 * @param {HookContext} context The hook context.
 * @returns {Promise<HookExecutionResult>}
 */
export const validateInputHook = async (context: HookContext): Promise<HookExecutionResult> => {
  logger.info('Executing pre-execution hook: validateInputHook');
  // Example: Check if required fields are present in context.data
  if (!context.data || !context.data.payload) {
    return { success: false, message: 'Input payload is missing.' };
  }
  // More complex validation logic here
  logger.debug('Input validation passed.');
  return { success: true, message: 'Input validated.' };
};

/**
 * Pre-execution hook: Authenticates the request or agent.
 * @param {HookContext} context The hook context.
 * @returns {Promise<HookExecutionResult>}
 */
export const authenticateRequestHook = async (context: HookContext): Promise<HookExecutionResult> => {
  logger.info('Executing pre-execution hook: authenticateRequestHook');
  // Example: Check for a valid authentication token in context.data
  if (!context.data || !context.data.authToken) {
    return { success: false, message: 'Authentication token is missing.' };
  }
  // Validate token against an auth service
  logger.debug('Request authenticated.');
  return { success: true, message: 'Request authenticated.' };
};

/**
 * Post-execution hook: Logs the execution result.
 * @param {HookContext} context The hook context.
 * @returns {Promise<HookExecutionResult>}
 */
export const logResultHook = async (context: HookContext): Promise<HookExecutionResult> => {
  logger.info('Executing post-execution hook: logResultHook');
  logger.debug('Execution result:', context.data);
  // Store logs in Cloud Logging or a database
  return { success: true, message: 'Result logged.' };
};

/**
 * Post-execution hook: Cleans up temporary resources.
 * @param {HookContext} context The hook context.
 * @returns {Promise<HookExecutionResult>}
 */
export const cleanupResourcesHook = async (context: HookContext): Promise<HookExecutionResult> => {
  logger.info('Executing post-execution hook: cleanupResourcesHook');
  // Example: Delete temporary files, close connections
  logger.debug('Temporary resources cleaned up.');
  return { success: true, message: 'Resources cleaned up.' };
};

/**
 * Error hook: Handles exceptions and triggers alerts.
 * @param {HookContext} context The hook context (should contain error details).
 * @returns {Promise<HookExecutionResult>}
 */
export const handleErrorHook = async (context: HookContext): Promise<HookExecutionResult> => {
  logger.error('Executing error hook: handleErrorHook', context.data.error);
  // Example: Report error to Google Cloud Error Reporting, send notification
  return { success: true, message: `Error handled: ${context.data.error.message}` };
};

/**
 * Performance hook: Collects execution metrics.
 * @param {HookContext} context The hook context.
 * @returns {Promise<HookExecutionResult>}
 */
export const collectPerformanceMetricsHook = async (context: HookContext): Promise<HookExecutionResult> => {
  logger.info('Executing performance hook: collectPerformanceMetricsHook');
  const startTime = context.data.startTime;
  const endTime = Date.now();
  const duration = endTime - startTime;
  logger.debug(`Operation duration: ${duration}ms`);
  // Store metrics in Cloud Monitoring or a performance database
  return { success: true, message: `Metrics collected. Duration: ${duration}ms` };
};

/**
 * Security hook: Performs audit logging.
 * @param {HookContext} context The hook context.
 * @returns {Promise<HookExecutionResult>}
 */
export const auditLogHook = async (context: HookContext): Promise<HookExecutionResult> => {
  logger.info('Executing security hook: auditLogHook');
  logger.debug('Audit log entry:', { user: context.data.userId, action: context.event.type, status: context.data.status });
  // Send audit logs to Cloud Logging or Security Command Center
  return { success: true, message: 'Audit log recorded.' };
};