zap-stream-flutter/lib/login.dart

import 'dart:convert';
import 'dart:developer' as developer;

import 'package:flutter/widgets.dart';
import 'package:flutter_secure_storage/flutter_secure_storage.dart';
import 'package:ndk/domain_layer/entities/account.dart';
import 'package:ndk/shared/nips/nip01/bip340.dart';
import 'package:ndk/shared/nips/nip19/nip19.dart';

class Account {
  final AccountType type;
  final String pubkey;
  final String? privateKey;

  Account._({required this.type, required this.pubkey, this.privateKey});

  static Account nip19(String key) {
    final keyData = Nip19.decode(key);
    final pubkey =
        Nip19.isKey("nsec", key) ? Bip340.getPublicKey(keyData) : keyData;
    final privateKey = Nip19.isKey("npub", key) ? null : keyData;
    return Account._(
      type: AccountType.privateKey,
      pubkey: pubkey,
      privateKey: privateKey,
    );
  }

  static Account privateKeyHex(String key) {
    return Account._(
      type: AccountType.privateKey,
      privateKey: key,
      pubkey: Bip340.getPublicKey(key),
    );
  }

  static Account externalPublicKeyHex(String key) {
    return Account._(type: AccountType.externalSigner, pubkey: key);
  }

  static Map<String, dynamic> toJson(Account? acc) => {
    "type": acc?.type.name,
    "pubKey": acc?.pubkey,
    "privateKey": acc?.privateKey,
  };

  static Account? fromJson(Map<String, dynamic> json) {
    if (json.length > 2 && json.containsKey("pubKey")) {
      return Account._(
        type: AccountType.values.firstWhere(
          (v) => v.toString().endsWith(json["type"] as String),
        ),
        pubkey: json["pubKey"],
        privateKey: json["privateKey"],
      );
    }
    return null;
  }
}

class LoginData extends ValueNotifier<Account?> {
  final _storage = FlutterSecureStorage();
  static const String _storageKey = "accounts";

  LoginData() : super(null) {
    super.addListener(() async {
      final data = json.encode(Account.toJson(value));
      await _storage.write(key: _storageKey, value: data);
    });
  }

  Future<void> logout() async {
    super.value = null;
    await _storage.delete(key: _storageKey);
  }

  Future<void> load() async {
    final acc = await _storage.read(key: _storageKey);
    if (acc?.isNotEmpty ?? false) {
      try {
        super.value = Account.fromJson(json.decode(acc!));
      } catch (e) {
        developer.log(e.toString());
      }
    }
  }
}