import type { DeviceHardware, Fingerprint } from '../../../domain/device.js'

/**
 * Recursively sorts the keys of an object in alphabetical order
 * to produce a consistent (canonical) representation.
 */
function canonicalize<T>(obj: T): T {
  // Return immediately if obj is null, undefined, or not an object
  if (obj === null || typeof obj !== 'object') {
    return obj
  }

  // Handle arrays by recursively sorting each element
  if (Array.isArray(obj)) {
    return obj.map((item) => canonicalize(item)) as unknown as T
  }

  // Get all keys and sort them
  const sortedKeys = Object.keys(obj).sort()

  // Create a new object with sorted keys
  // biome-ignore lint/suspicious/noExplicitAny: <explanation>
  const result = {} as Record<string, any>

  // Add each key-value pair to the result object in sorted order
  for (const key of sortedKeys) {
    // Recursively sort nested objects
    // biome-ignore lint/suspicious/noExplicitAny: <explanation>
    result[key] = canonicalize((obj as Record<string, any>)[key])
  }

  return result as T
}

/**
 * Generates a hash from the hardware object using the Web Crypto API
 *
 */
async function generateHardwareHash(hardware: DeviceHardware) {
  // First, create a canonical version of the object
  const canonicalHardware = canonicalize<DeviceHardware>(hardware)

  // Convert the object to a JSON string
  const jsonString = JSON.stringify(canonicalHardware)

  // Encode the string as UTF-8
  const encoder = new TextEncoder()
  const data = encoder.encode(jsonString)

  // Calculate the SHA-256 digest
  const hashBuffer = await crypto.subtle.digest('SHA-256', data)

  // Convert the ArrayBuffer to a hex string
  const hashArray = new Uint8Array(hashBuffer)
  const hashHex = Array.from(hashArray)
    .map((byte) => byte.toString(16).padStart(2, '0'))
    .join('')

  return hashHex
}

export async function createFingerprint(
  hardware: DeviceHardware,
): Promise<Fingerprint> {
  const fingerprint = await generateHardwareHash(hardware)

  return fingerprint as Fingerprint
}