import {Platform} from 'react-native'

/**
 * Detect connection type from address format
 * @param address Device address (MAC, UUID, or IP:PORT)
 * @returns Connection type: 'ble', 'bt', 'lan', or null if cannot detect
 */
export function detectAddressType(address: string): 'ble' | 'bt' | 'lan' | null {
  if (!address) return null

  // Check if already has type prefix
  if (address.startsWith('ble:') || address.startsWith('bt:') || address.startsWith('lan:')) {
    return address.split(':')[0] as 'ble' | 'bt' | 'lan'
  }

  // LAN: IP address format (with or without port)
  // IPv4: xxx.xxx.xxx.xxx or xxx.xxx.xxx.xxx:port
  const ipv4Pattern = /^(\d{1,3}\.){3}\d{1,3}(:\d{1,5})?$/
  if (ipv4Pattern.test(address)) {
    return 'lan'
  }

  // BLE on iOS: UUID format
  // Format: XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX (8-4-4-4-12)
  const uuidPattern = /^[0-9a-f]{8}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{12}$/i
  if (uuidPattern.test(address)) {
    return 'ble'
  }

  // Bluetooth Classic/BLE on Android: MAC address
  // Format: XX:XX:XX:XX:XX:XX
  const macPattern = /^([0-9a-f]{2}:){5}[0-9a-f]{2}$/i
  if (macPattern.test(address)) {
    // On iOS, MAC addresses are usually BLE
    // On Android, could be either BLE or Classic
    // Default to 'bt' for Android, 'ble' for iOS
    return Platform.OS === 'ios' ? 'ble' : 'bt'
  }

  // IPv6 (less common for printers)
  if (address.includes('::') || address.split(':').length > 6) {
    return 'lan'
  }

  return null
}

/**
 * Helper function to build printer address
 * @param typeOrAddress Connection type ('ble', 'bt', 'lan') or just the address
 * @param identifier Optional device identifier if type is provided
 * @returns Formatted address string
 * @example
 * buildAddress('ble', 'XX:XX:XX:XX:XX:XX') => 'ble:XX:XX:XX:XX:XX:XX'
 * buildAddress('192.168.1.100:9100') => 'lan:192.168.1.100:9100'
 * buildAddress('XX:XX:XX:XX:XX:XX') => 'bt:XX:XX:XX:XX:XX:XX' (Android) or 'ble:XX:XX:XX:XX:XX:XX' (iOS)
 */
export function buildAddress(typeOrAddress: string, identifier?: string): string {
  // If identifier is provided, treat first param as type
  if (identifier) {
    return `${typeOrAddress}:${identifier}`
  }

  // Otherwise, first param is the address - detect type
  const address = typeOrAddress

  // Check if already formatted
  if (address.includes(':')) {
    const parts = address.split(':')
    if (['ble', 'bt', 'lan'].includes(parts[0])) {
      return address // Already formatted
    }
  }

  // Auto-detect type
  const detectedType = detectAddressType(address)
  if (detectedType) {
    return `${detectedType}:${address}`
  }

  // If cannot detect, assume based on platform
  console.warn(`[JS] ConnectionUtils.normalizeAddress - WARN: Cannot detect type for ${address}, using platform default`)
  const defaultType = Platform.OS === 'ios' ? 'ble' : 'bt'
  return `${defaultType}:${address}`
}

/**
 * Helper function to parse printer address
 * @param address Printer address
 * @returns Object with type and identifier
 */
export function parseAddress(address: string): {type: string; identifier: string} {
  const [type, ...parts] = address.split(':')
  return {
    type,
    identifier: parts.join(':'),
  }
}