shannon/src/error-handling.ts

// Copyright (C) 2025 Keygraph, Inc.
//
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU Affero General Public License version 3
// as published by the Free Software Foundation.

import chalk from 'chalk';
import { fs, path } from 'zx';
import type {
  PentestErrorType,
  PentestErrorContext,
  LogEntry,
  ToolErrorResult,
  PromptErrorResult,
} from './types/errors.js';

// Custom error class for pentest operations
export class PentestError extends Error {
  name = 'PentestError' as const;
  type: PentestErrorType;
  retryable: boolean;
  context: PentestErrorContext;
  timestamp: string;

  constructor(
    message: string,
    type: PentestErrorType,
    retryable: boolean = false,
    context: PentestErrorContext = {}
  ) {
    super(message);
    this.type = type;
    this.retryable = retryable;
    this.context = context;
    this.timestamp = new Date().toISOString();
  }
}

// Centralized error logging function
export const logError = async (
  error: Error & { type?: PentestErrorType; retryable?: boolean; context?: PentestErrorContext },
  contextMsg: string,
  sourceDir: string | null = null
): Promise<LogEntry> => {
  const timestamp = new Date().toISOString();
  const logEntry: LogEntry = {
    timestamp,
    context: contextMsg,
    error: {
      name: error.name || error.constructor.name,
      message: error.message,
      type: error.type || 'unknown',
      retryable: error.retryable || false,
    },
  };
  // Only add stack if it exists
  if (error.stack) {
    logEntry.error.stack = error.stack;
  }

  // Console logging with color
  const prefix = error.retryable ? '⚠️' : '❌';
  const color = error.retryable ? chalk.yellow : chalk.red;
  console.log(color(`${prefix} ${contextMsg}:`));
  console.log(color(`   ${error.message}`));

  if (error.context && Object.keys(error.context).length > 0) {
    console.log(chalk.gray(`   Context: ${JSON.stringify(error.context)}`));
  }

  // File logging (if source directory available)
  if (sourceDir) {
    try {
      const logPath = path.join(sourceDir, 'error.log');
      await fs.appendFile(logPath, JSON.stringify(logEntry) + '\n');
    } catch (logErr) {
      const errMsg = logErr instanceof Error ? logErr.message : String(logErr);
      console.log(chalk.gray(`   (Failed to write error log: ${errMsg})`));
    }
  }

  return logEntry;
};

// Handle tool execution errors
export const handleToolError = (
  toolName: string,
  error: Error & { code?: string }
): ToolErrorResult => {
  const isRetryable =
    error.code === 'ECONNRESET' ||
    error.code === 'ETIMEDOUT' ||
    error.code === 'ENOTFOUND';

  return {
    tool: toolName,
    output: `Error: ${error.message}`,
    status: 'error',
    duration: 0,
    success: false,
    error: new PentestError(
      `${toolName} execution failed: ${error.message}`,
      'tool',
      isRetryable,
      { toolName, originalError: error.message, errorCode: error.code }
    ),
  };
};

// Handle prompt loading errors
export const handlePromptError = (
  promptName: string,
  error: Error
): PromptErrorResult => {
  return {
    success: false,
    error: new PentestError(
      `Failed to load prompt '${promptName}': ${error.message}`,
      'prompt',
      false,
      { promptName, originalError: error.message }
    ),
  };
};

// Check if an error should trigger a retry for Claude agents
export const isRetryableError = (error: Error): boolean => {
  const message = error.message.toLowerCase();

  // Network and connection errors - always retryable
  if (
    message.includes('network') ||
    message.includes('connection') ||
    message.includes('timeout') ||
    message.includes('econnreset') ||
    message.includes('enotfound') ||
    message.includes('econnrefused')
  ) {
    return true;
  }

  // Rate limiting - retryable with longer backoff
  if (
    message.includes('rate limit') ||
    message.includes('429') ||
    message.includes('too many requests')
  ) {
    return true;
  }

  // Server errors - retryable
  if (
    message.includes('server error') ||
    message.includes('5xx') ||
    message.includes('internal server error') ||
    message.includes('service unavailable') ||
    message.includes('bad gateway')
  ) {
    return true;
  }

  // Claude API specific errors - retryable
  if (
    message.includes('mcp server') ||
    message.includes('model unavailable') ||
    message.includes('service temporarily unavailable') ||
    message.includes('api error') ||
    message.includes('terminated')
  ) {
    return true;
  }

  // Max turns without completion - retryable once
  if (message.includes('max turns') || message.includes('maximum turns')) {
    return true;
  }

  // Non-retryable errors
  if (
    message.includes('authentication') ||
    message.includes('invalid prompt') ||
    message.includes('out of memory') ||
    message.includes('permission denied') ||
    message.includes('session limit reached') ||
    message.includes('invalid api key')
  ) {
    return false;
  }

  // Default to non-retryable for unknown errors
  return false;
};

// Get retry delay based on error type and attempt number
export const getRetryDelay = (error: Error, attempt: number): number => {
  const message = error.message.toLowerCase();

  // Rate limiting gets longer delays
  if (message.includes('rate limit') || message.includes('429')) {
    return Math.min(30000 + attempt * 10000, 120000); // 30s, 40s, 50s, max 2min
  }

  // Exponential backoff with jitter for other retryable errors
  const baseDelay = Math.pow(2, attempt) * 1000; // 2s, 4s, 8s
  const jitter = Math.random() * 1000; // 0-1s random
  return Math.min(baseDelay + jitter, 30000); // Max 30s
};