Envelope/mobile/lib/models/conversations.dart

import 'dart:convert';
import 'dart:typed_data';
import 'package:Envelope/models/conversation_users.dart';
import 'package:Envelope/models/friends.dart';
import 'package:Envelope/models/my_profile.dart';
import 'package:pointycastle/export.dart';
import 'package:sqflite/sqflite.dart';
import 'package:uuid/uuid.dart';
import '/utils/encryption/crypto_utils.dart';
import '/utils/encryption/aes_helper.dart';
import '/utils/storage/database.dart';
import '/utils/strings.dart';

Conversation findConversationByDetailId(List<Conversation> conversations, String id) {
  for (var conversation in conversations) {
    if (conversation.conversationDetailId == id) {
      return conversation;
    }
  }
  // Or return `null`.
  throw ArgumentError.value(id, "id", "No element with that id");
}

class Conversation {
  String id;
  String userId;
  String conversationDetailId;
  String symmetricKey;
  bool admin;
  String name;

  Conversation({
    required this.id,
    required this.userId,
    required this.conversationDetailId,
    required this.symmetricKey,
    required this.admin,
    required this.name,
  });


  factory Conversation.fromJson(Map<String, dynamic> json, RSAPrivateKey privKey) {
    var symmetricKeyDecrypted = CryptoUtils.rsaDecrypt(
        base64.decode(json['symmetric_key']),
        privKey,
    );

    var detailId = AesHelper.aesDecrypt(
        symmetricKeyDecrypted,
        base64.decode(json['conversation_detail_id']),
    );

    var admin = AesHelper.aesDecrypt(
        symmetricKeyDecrypted,
        base64.decode(json['admin']),
    );

    return Conversation(
        id: json['id'],
        userId: json['user_id'],
        conversationDetailId: detailId,
        symmetricKey: base64.encode(symmetricKeyDecrypted),
        admin: admin == 'true',
        name: 'Unknown',
    );
  }

  @override
  String toString() {
    return '''


        id: $id
        userId: $userId
        name: $name
        admin: $admin''';
  }

  Map<String, dynamic> toMap() {
    return {
      'id': id,
      'user_id': userId,
      'conversation_detail_id': conversationDetailId,
      'symmetric_key': symmetricKey,
      'admin': admin ? 1 : 0,
      'name': name,
    };
  }
}

Future<Conversation> createConversation(String title, List<Friend> friends) async {
  final db = await getDatabaseConnection();

  MyProfile profile = await MyProfile.getProfile();

  var uuid = const Uuid();
  final String conversationId = uuid.v4();

  Uint8List symmetricKey = AesHelper.deriveKey(generateRandomString(32));

  String associationKey = generateRandomString(32);

  Conversation conversation = Conversation(
    id: conversationId,
    userId: profile.id,
    conversationDetailId: '',
    symmetricKey: base64.encode(symmetricKey),
    admin: true,
    name: title,
  );

  await db.insert(
      'conversations',
      conversation.toMap(),
      conflictAlgorithm: ConflictAlgorithm.replace,
  );

  await db.insert(
      'conversation_users',
      ConversationUser(
          id: uuid.v4(),
          conversationId: conversationId,
          username: profile.username,
          associationKey: associationKey,
          admin: false,
      ).toMap(),
      conflictAlgorithm: ConflictAlgorithm.replace,
  );

  for (Friend friend in friends) {
    await db.insert(
        'conversation_users',
        ConversationUser(
            id: uuid.v4(),
            conversationId: conversationId,
            username: friend.username,
            associationKey: associationKey,
            admin: false,
        ).toMap(),
        conflictAlgorithm: ConflictAlgorithm.replace,
    );
  }

  return conversation;
}

// A method that retrieves all the dogs from the dogs table.
Future<List<Conversation>> getConversations() async {
  final db = await getDatabaseConnection();

  final List<Map<String, dynamic>> maps = await db.query('conversations');

  return List.generate(maps.length, (i) {
    return Conversation(
        id: maps[i]['id'],
        userId: maps[i]['user_id'],
        conversationDetailId: maps[i]['conversation_detail_id'],
        symmetricKey: maps[i]['symmetric_key'],
        admin: maps[i]['admin'] == 1,
        name: maps[i]['name'],
    );
  });
}