localsend/app/lib/util/fingerprint_alphabet.dart

import 'dart:convert';
import 'dart:math';

import 'package:crypto/crypto.dart';
import 'package:flutter/material.dart';

/// The icon alphabet used to visualize fingerprints.
const iconAlphabet = <IconData>[
  Icons.ac_unit,
  Icons.access_alarm,
  Icons.access_time,
  Icons.accessibility,
  Icons.accessibility_new,
  Icons.account_balance,
  Icons.account_balance_wallet,
  Icons.account_box,
  Icons.account_circle,
  Icons.adb,
  Icons.add,
  Icons.add_a_photo,
  Icons.add_alarm,
  Icons.add_alert,
  Icons.add_box,
  Icons.add_circle,
  Icons.add_circle_outline,
  Icons.add_comment,
  Icons.add_location,
  Icons.add_photo_alternate,
  Icons.add_shopping_cart,
  Icons.alarm,
  Icons.alarm_add,
  Icons.alarm_off,
  Icons.alarm_on,
  Icons.album,
  Icons.all_inbox,
  Icons.all_inclusive,
  Icons.analytics,
  Icons.android,
  Icons.announcement,
  Icons.api,
  Icons.app_blocking,
  Icons.app_registration,
  Icons.app_settings_alt,
  Icons.apple,
  Icons.apps,
  Icons.archive,
  Icons.arrow_back,
  Icons.arrow_back_ios,
  Icons.arrow_downward,
  Icons.arrow_drop_down,
  Icons.arrow_drop_up,
  Icons.arrow_forward,
  Icons.arrow_forward_ios,
  Icons.arrow_left,
  Icons.arrow_right,
  Icons.arrow_upward,
  Icons.article,
  Icons.aspect_ratio,
  Icons.assessment,
  Icons.assignment,
  Icons.assignment_ind,
  Icons.assignment_late,
  Icons.assignment_return,
  Icons.assignment_turned_in,
  Icons.assistant,
  Icons.attach_email,
  Icons.attach_file,
  Icons.attach_money,
  Icons.attachment,
  Icons.attribution,
  Icons.audiotrack,
  Icons.auto_awesome,
  Icons.auto_delete,
  Icons.auto_fix_high,
  Icons.autorenew,
  Icons.backspace,
  Icons.backup,
  Icons.badge,
  Icons.bar_chart,
  Icons.batch_prediction,
  Icons.battery_charging_full,
  Icons.battery_full,
  Icons.battery_std,
  Icons.beach_access,
  Icons.beenhere,
  Icons.block,
  Icons.bluetooth,
  Icons.bluetooth_connected,
  Icons.bluetooth_disabled,
  Icons.bluetooth_searching,
  Icons.book,
  Icons.bookmark,
  Icons.bookmark_border,
  Icons.bookmarks,
  Icons.border_all,
  Icons.border_color,
  Icons.build,
  Icons.business,
  Icons.business_center,
  Icons.calculate,
  Icons.calendar_today,
  Icons.call,
  Icons.call_end,
  Icons.call_made,
  Icons.call_merge,
  Icons.call_missed,
  Icons.call_received,
  Icons.call_split,
  Icons.camera,
  Icons.camera_alt,
  Icons.camera_enhance,
  Icons.camera_front,
  Icons.camera_rear,
  Icons.cancel,
  Icons.card_giftcard,
  Icons.card_membership,
  Icons.card_travel,
  Icons.category,
  Icons.chat,
  Icons.chat_bubble,
  Icons.chat_bubble_outline,
  Icons.check,
  Icons.check_box,
  Icons.check_box_outline_blank,
  Icons.check_circle,
  Icons.check_circle_outline,
  Icons.chevron_left,
  Icons.chevron_right,
  Icons.clear,
  Icons.close,
  Icons.cloud,
  Icons.cloud_circle,
  Icons.cloud_download,
  Icons.cloud_off,
  Icons.cloud_queue,
  Icons.cloud_upload,
  Icons.code,
  Icons.comment,
  Icons.computer,
  Icons.contact_mail,
  Icons.contact_phone,
  Icons.contact_support,
  Icons.contacts,
  Icons.content_copy,
  Icons.content_cut,
  Icons.content_paste,
  Icons.credit_card,
  Icons.crop,
  Icons.dashboard,
  Icons.data_usage,
  Icons.delete,
  Icons.delete_forever,
  Icons.delete_outline,
  Icons.description,
  Icons.desktop_mac,
  Icons.desktop_windows,
  Icons.details,
  Icons.developer_board,
  Icons.developer_mode,
  Icons.device_hub,
  Icons.devices,
  Icons.dialpad,
  Icons.directions,
  Icons.directions_bike,
  Icons.directions_bus,
  Icons.directions_car,
  Icons.directions_run,
  Icons.directions_walk,
  Icons.disc_full,
  Icons.dns,
  Icons.done,
  Icons.done_all,
  Icons.done_outline,
  Icons.drafts,
  Icons.edit,
  Icons.edit_location,
  Icons.email,
  Icons.error,
  Icons.error_outline,
  Icons.event,
  Icons.event_available,
  Icons.event_busy,
  Icons.event_note,
  Icons.event_seat,
  Icons.exit_to_app,
  Icons.expand_less,
  Icons.expand_more,
  Icons.explicit,
  Icons.explore,
  Icons.extension,
  Icons.face,
  Icons.facebook,
  Icons.fast_forward,
  Icons.fast_rewind,
  Icons.favorite,
  Icons.favorite_border,
  Icons.featured_play_list,
  Icons.featured_video,
  Icons.feedback,
  Icons.file_download,
  Icons.file_upload,
  Icons.filter,
  Icons.filter_alt,
  Icons.filter_list,
  Icons.find_in_page,
  Icons.fingerprint,
  Icons.flag,
  Icons.flash_auto,
  Icons.flash_off,
  Icons.flash_on,
  Icons.flight,
  Icons.flight_land,
  Icons.flight_takeoff,
  Icons.folder,
  Icons.folder_open,
  Icons.folder_shared,
  Icons.forum,
  Icons.forward,
  Icons.fullscreen,
  Icons.fullscreen_exit,
  Icons.games,
  Icons.gavel,
  Icons.gesture,
  Icons.get_app,
  Icons.gif,
  Icons.grade,
  Icons.group,
  Icons.group_add,
  Icons.group_work,
  Icons.hd,
  Icons.headset,
  Icons.headset_mic,
  Icons.healing,
  Icons.hearing,
  Icons.help,
  Icons.help_outline,
  Icons.history,
  Icons.home,
  Icons.hotel,
  Icons.hourglass_empty,
  Icons.hourglass_full,
  Icons.http,
  Icons.https,
  Icons.image,
  Icons.image_aspect_ratio,
  Icons.import_contacts,
  Icons.import_export,
  Icons.inbox,
  Icons.info,
  Icons.info_outline,
  Icons.input,
  Icons.key,
  Icons.keyboard,
  Icons.label,
  Icons.landscape,
  Icons.language,
  Icons.laptop,
  Icons.launch,
  Icons.layers,
  Icons.lightbulb,
  Icons.link,
  Icons.list,
  Icons.local_activity,
  Icons.local_airport,
  Icons.local_atm,
  Icons.local_bar,
  Icons.local_cafe,
  Icons.local_dining,
  Icons.local_grocery_store,
  Icons.local_hospital,
  Icons.local_hotel,
  Icons.local_offer,
  Icons.local_phone,
  Icons.local_pizza,
  Icons.local_post_office,
  Icons.local_see,
  Icons.local_shipping,
  Icons.local_taxi,
  Icons.lock,
  Icons.lock_open,
];

/// Hashes the [combined] fingerprints and renders the first 128 bits as 16 icons of [iconAlphabet].
List<IconData> fingerprintToIcons(String combined) {
  final digest = sha256.convert(utf8.encode(combined));
  final hex = digest.bytes.sublist(0, 16).map((b) => b.toRadixString(16).padLeft(2, '0')).join();
  return convertFingerprintToAlphabet(fingerprint: hex, alphabet: iconAlphabet);
}

/// Converts a hex [fingerprint] to a sequence of items of [alphabet] using base conversion.
/// The result has a fixed length depending only on the input and alphabet sizes.
List<T> convertFingerprintToAlphabet<T>({
  required String fingerprint,
  required List<T> alphabet,
}) {
  final base = BigInt.from(alphabet.length);
  final length = (fingerprint.length * 4 * log(2) / log(alphabet.length)).ceil();
  var value = BigInt.parse(fingerprint, radix: 16);
  final result = List<T>.filled(length, alphabet[0]);
  for (var i = length - 1; i >= 0; i--) {
    result[i] = alphabet[(value % base).toInt()];
    value ~/= base;
  }
  return result;
}