/**
 * Custom Application Error class for consistent error handling
 * Extends the built-in Error class with additional properties
 */
class AppError extends Error {
  /**
   * Create an application error
   * @param {string} message - Error message
   * @param {number} statusCode - HTTP status code
   * @param {boolean} isOperational - Whether the error is operational (expected) or programming error
   */
  constructor(message, statusCode = 500, isOperational = true) {
    super(message);
    
    this.statusCode = statusCode;
    this.status = `${statusCode}`.startsWith('4') ? 'fail' : 'error';
    this.isOperational = isOperational;
    
    // Capture stack trace
    Error.captureStackTrace(this, this.constructor);
  }
}

/**
 * Create a Bad Request error (400)
 */
class BadRequestError extends AppError {
  constructor(message = 'Bad Request') {
    super(message, 400);
  }
}

/**
 * Create an Unauthorized error (401)
 */
class UnauthorizedError extends AppError {
  constructor(message = 'Unauthorized') {
    super(message, 401);
  }
}

/**
 * Create a Forbidden error (403)
 */
class ForbiddenError extends AppError {
  constructor(message = 'Forbidden') {
    super(message, 403);
  }
}

/**
 * Create a Not Found error (404)
 */
class NotFoundError extends AppError {
  constructor(message = 'Resource not found') {
    super(message, 404);
  }
}

/**
 * Create a Conflict error (409)
 */
class ConflictError extends AppError {
  constructor(message = 'Resource conflict') {
    super(message, 409);
  }
}

/**
 * Create an Unprocessable Entity error (422)
 */
class ValidationError extends AppError {
  constructor(message = 'Validation failed', errors = null) {
    super(message, 422);
    this.errors = errors;
  }
}

/**
 * Create an Internal Server Error (500)
 */
class InternalServerError extends AppError {
  constructor(message = 'Internal server error') {
    super(message, 500, false);
  }
}

/**
 * Create a Database Error
 */
class DatabaseError extends AppError {
  constructor(message = 'Database error', originalError = null) {
    super(message, 500, false);
    this.originalError = originalError;
  }
}

module.exports = {
  AppError,
  BadRequestError,
  UnauthorizedError,
  ForbiddenError,
  NotFoundError,
  ConflictError,
  ValidationError,
  InternalServerError,
  DatabaseError
};