tauri-plugins-workspace/plugins/nfc/guest-js/index.ts

// Copyright 2019-2023 Tauri Programme within The Commons Conservancy
// SPDX-License-Identifier: Apache-2.0
// SPDX-License-Identifier: MIT

import { invoke } from '@tauri-apps/api/core'

export const RTD_TEXT = [0x54] // "T"
export const RTD_URI = [0x55] // "U"

export interface UriFilter {
  scheme?: string
  host?: string
  pathPrefix?: string
}

export enum TechKind {
  IsoDep,
  MifareClassic,
  MifareUltralight,
  Ndef,
  NdefFormatable,
  NfcA,
  NfcB,
  NfcBarcode,
  NfcF,
  NfcV
}

export type ScanKind =
  | {
      type: 'tag'
      uri?: UriFilter
      mimeType?: string
    }
  | {
      type: 'ndef'
      uri?: UriFilter
      mimeType?: string
      /**
       *  Each of the tech-lists is considered independently and the activity is considered a match if
       * any single tech-list matches the tag that was discovered.
       * This provides AND and OR semantics for filtering desired techs.
       *
       * See <https://developer.android.com/reference/android/nfc/NfcAdapter#ACTION_TECH_DISCOVERED> for more information.
       *
       * Examples
       *
       * ```ts
       * import type { TechKind } from "@tauri-apps/plugin-nfc"
       *
       * const techLists = [
       *  // capture anything using NfcF
       *  [TechKind.NfcF],
       *  // capture all MIFARE Classics with NDEF payloads
       *  [TechKind.NfcA, TechKind.MifareClassic, TechKind.Ndef]
       * ]
       * ```
       */
      techLists?: TechKind[][]
    }

export interface ScanOptions {
  keepSessionAlive?: boolean
  /** Message displayed in the UI. iOS only. */
  message?: string
  /** Message displayed in the UI when the message has been read. iOS only. */
  successMessage?: string
}

export interface WriteOptions {
  kind?: ScanKind
  /** Message displayed in the UI when reading the tag. iOS only. */
  message?: string
  /** Message displayed in the UI when the tag has been read. iOS only. */
  successfulReadMessage?: string
  /** Message displayed in the UI when the message has been written. iOS only. */
  successMessage?: string
}

export enum NFCTypeNameFormat {
  Empty = 0,
  NfcWellKnown = 1,
  Media = 2,
  AbsoluteURI = 3,
  NfcExternal = 4,
  Unknown = 5,
  Unchanged = 6
}

export interface TagRecord {
  tnf: NFCTypeNameFormat
  kind: number[]
  id: number[]
  payload: number[]
}

export interface Tag {
  id: number[]
  kind: string[]
  records: TagRecord[]
}

export interface NFCRecord {
  format: NFCTypeNameFormat
  kind: number[]
  id: number[]
  payload: number[]
}

export function record(
  format: NFCTypeNameFormat,
  kind: string | number[],
  id: string | number[],
  payload: string | number[]
): NFCRecord {
  return {
    format,
    kind:
      typeof kind === 'string'
        ? Array.from(new TextEncoder().encode(kind))
        : kind,
    id: typeof id === 'string' ? Array.from(new TextEncoder().encode(id)) : id,
    payload:
      typeof payload === 'string'
        ? Array.from(new TextEncoder().encode(payload))
        : payload
  }
}

export function textRecord(
  text: string,
  id?: string | number[],
  language: string = 'en'
): NFCRecord {
  const payload = Array.from(new TextEncoder().encode(language + text))
  payload.unshift(language.length)
  return record(NFCTypeNameFormat.NfcWellKnown, RTD_TEXT, id ?? [], payload)
}

const protocols = [
  '',
  'http://www.',
  'https://www.',
  'http://',
  'https://',
  'tel:',
  'mailto:',
  'ftp://anonymous:anonymous@',
  'ftp://ftp.',
  'ftps://',
  'sftp://',
  'smb://',
  'nfs://',
  'ftp://',
  'dav://',
  'news:',
  'telnet://',
  'imap:',
  'rtsp://',
  'urn:',
  'pop:',
  'sip:',
  'sips:',
  'tftp:',
  'btspp://',
  'btl2cap://',
  'btgoep://',
  'tcpobex://',
  'irdaobex://',
  'file://',
  'urn:epc:id:',
  'urn:epc:tag:',
  'urn:epc:pat:',
  'urn:epc:raw:',
  'urn:epc:',
  'urn:nfc:'
]

function encodeURI(uri: string): number[] {
  let prefix = ''

  protocols.slice(1).forEach(function (protocol) {
    if (
      (prefix.length === 0 || prefix === 'urn:')
      && uri.indexOf(protocol) === 0
    ) {
      prefix = protocol
    }
  })

  if (prefix.length === 0) {
    prefix = ''
  }

  const encoded = Array.from(new TextEncoder().encode(uri.slice(prefix.length)))
  const protocolCode = protocols.indexOf(prefix)
  // prepend protocol code
  encoded.unshift(protocolCode)

  return encoded
}

export function uriRecord(uri: string, id?: string | number[]): NFCRecord {
  return record(
    NFCTypeNameFormat.NfcWellKnown,
    RTD_URI,
    id ?? [],
    encodeURI(uri)
  )
}

function mapScanKind(kind: ScanKind): Record<string, unknown> {
  const { type: scanKind, ...kindOptions } = kind
  return { [scanKind]: kindOptions }
}

/**
 * Scans an NFC tag.
 *
 * ```javascript
 * import { scan } from "@tauri-apps/plugin-nfc";
 * await scan({ type: "tag" });
 * ```
 *
 * See <https://developer.android.com/develop/connectivity/nfc/nfc#ndef> for more information.
 *
 * @param kind
 * @param options
 * @returns
 */
export async function scan(
  kind: ScanKind,
  options?: ScanOptions
): Promise<Tag> {
  return await invoke('plugin:nfc|scan', {
    kind: mapScanKind(kind),
    ...options
  })
}

/**
 * Write to an NFC tag.
 *
 * ```javascript
 * import { uriRecord, write } from "@tauri-apps/plugin-nfc";
 * await write([uriRecord("https://tauri.app")], { kind: { type: "ndef" } });
 * ```
 *
 * If you did not previously call {@link scan} with {@link ScanOptions.keepSessionAlive} set to true,
 * it will first scan the tag then write to it.
 *
 * @param records
 * @param options
 * @returns
 */
export async function write(
  records: NFCRecord[],
  options?: WriteOptions
): Promise<void> {
  const { kind, ...opts } = options ?? {}
  if (kind) {
    // @ts-expect-error map the property
    opts.kind = mapScanKind(kind)
  }
  await invoke('plugin:nfc|write', {
    records,
    ...opts
  })
}

export async function isAvailable(): Promise<boolean> {
  return await invoke('plugin:nfc|is_available')
}