/**
 * Error classification system for actionable error messages
 */

export type ErrorType = 'network' | 'payment' | 'validation' | 'loading' | 'unknown'

export interface ErrorClassification {
  type: ErrorType
  message: string
  suggestion?: string
  canRetry: boolean
  canCheckConnection: boolean
  needsDocumentation: boolean
}

function isNetworkError(lowerMessage: string): boolean {
  return (
    lowerMessage.includes('network') ||
    lowerMessage.includes('fetch') ||
    lowerMessage.includes('timeout') ||
    lowerMessage.includes('timed out') ||
    lowerMessage.includes('econnreset') ||
    lowerMessage.includes('econnrefused') ||
    lowerMessage.includes('enotfound') ||
    lowerMessage.includes('eai_again') ||
    lowerMessage.includes('dns') ||
    lowerMessage.includes('failed to fetch')
  )
}

function isPaymentError(lowerMessage: string): boolean {
  return (
    lowerMessage.includes('payment') ||
    lowerMessage.includes('invoice') ||
    lowerMessage.includes('webln') ||
    lowerMessage.includes('alby') ||
    lowerMessage.includes('insufficient funds') ||
    lowerMessage.includes('funds')
  )
}

function isValidationError(lowerMessage: string): boolean {
  return (
    lowerMessage.includes('invalid') ||
    lowerMessage.includes('validation') ||
    lowerMessage.includes('required') ||
    lowerMessage.includes('missing')
  )
}

function isLoadingError(lowerMessage: string): boolean {
  return (
    lowerMessage.includes('loading') ||
    lowerMessage.includes('failed to load') ||
    lowerMessage.includes('could not load')
  )
}

function createNetworkClassification(errorMessage: string): ErrorClassification {
  return {
    type: 'network',
    message: errorMessage,
    suggestion: 'errors.network.suggestion',
    canRetry: true,
    canCheckConnection: true,
    needsDocumentation: false,
  }
}

function createPaymentClassification(errorMessage: string): ErrorClassification {
  return {
    type: 'payment',
    message: errorMessage,
    suggestion: 'errors.payment.suggestion',
    canRetry: true,
    canCheckConnection: false,
    needsDocumentation: true,
  }
}

function createValidationClassification(errorMessage: string): ErrorClassification {
  return {
    type: 'validation',
    message: errorMessage,
    suggestion: 'errors.validation.suggestion',
    canRetry: false,
    canCheckConnection: false,
    needsDocumentation: false,
  }
}

function createLoadingClassification(errorMessage: string): ErrorClassification {
  return {
    type: 'loading',
    message: errorMessage,
    suggestion: 'errors.loading.suggestion',
    canRetry: true,
    canCheckConnection: true,
    needsDocumentation: false,
  }
}

function createUnknownClassification(errorMessage: string): ErrorClassification {
  return {
    type: 'unknown',
    message: errorMessage,
    suggestion: 'errors.unknown.suggestion',
    canRetry: true,
    canCheckConnection: false,
    needsDocumentation: false,
  }
}

/**
 * Classify an error to determine appropriate recovery actions
 */
export function classifyError(error: unknown): ErrorClassification {
  const errorMessage = error instanceof Error ? error.message : String(error)
  const lowerMessage = errorMessage.toLowerCase()

  if (isNetworkError(lowerMessage)) {
    return createNetworkClassification(errorMessage)
  }
  if (isPaymentError(lowerMessage)) {
    return createPaymentClassification(errorMessage)
  }
  if (isValidationError(lowerMessage)) {
    return createValidationClassification(errorMessage)
  }
  if (isLoadingError(lowerMessage)) {
    return createLoadingClassification(errorMessage)
  }

  return createUnknownClassification(errorMessage)
}

/**
 * Get user-friendly error message based on classification
 */
export function getUserFriendlyMessage(classification: ErrorClassification): string {
  return classification.message
}