public async Task <AddParticipantPayload> GetAddParticipantAsync(
AddParticipantInput input,
[ScopedService] ApplicationDbContext dbContext,
[Service] IHttpContextAccessor contextAccessor,
UserByIdDataLoader userById,
ChatByIdDataLoader chatById,
CancellationToken ct
)
{
var user = await userById.LoadAsync(input.UserId, ct) ?? throw new Exception("User not found.");
var chat = await chatById.LoadAsync(input.ChatId, ct) ?? throw new Exception("Chat not found.");
// Todo: Check if user is allowed to add participants --> add something like a groupadmin
var userChat = new UserChat
{
UserId = user.Id,
ChatId = chat.Id
};
chat.UserChats.Add(userChat);
await dbContext.SaveChangesAsync();
return(new AddParticipantPayload(chat));
}
public async Task <IEnumerable <Chat> > GetChatsAsync(
User user,
[ScopedService] ApplicationDbContext dbContext,
ChatByIdDataLoader chatById,
CancellationToken ct
)
{
int[] chatIds = await dbContext.Users
.Where(u => u.Id == user.Id)
.Include(u => u.UserChats)
.SelectMany(u => u.UserChats.Select(uc => uc.ChatId))
.ToArrayAsync();
return(await chatById.LoadAsync(chatIds, ct));
}
public async Task <IEnumerable <Chat> > GetChatsAsync(
[Service] IHttpContextAccessor contextAccessor,
[ScopedService] ApplicationDbContext dbContext,
ChatByIdDataLoader chatById,
CancellationToken ct
)
{
var httpContext = contextAccessor.HttpContext ?? throw new ArgumentNullException($"{nameof(contextAccessor.HttpContext)} cant't be null.");
var userId = httpContext.User.Claims.Where(uc => uc.Type == "sub").FirstOrDefault().Value;
int[] chatIds = await dbContext.Users
.Where(u => u.Id == userId)
.Include(u => u.UserChats)
.SelectMany(u => u.UserChats.Select(uc => uc.ChatId))
.ToArrayAsync();
return(await chatById.LoadAsync(chatIds, ct));
}
public async Task <SendMessagePayload> SendMessageAsync(
SendMessageInput input,
[ScopedService] ApplicationDbContext dbContext,
[Service] IHttpContextAccessor contextAccessor,
ChatByIdDataLoader chatById,
UserByIdDataLoader userById,
CancellationToken ct
)
{
var httpContext = contextAccessor.HttpContext ?? throw new ArgumentNullException($"{nameof(contextAccessor.HttpContext)} can't be null.");
var user = await userById.LoadAsync(httpContext.User.Claims.Where(uc => uc.Type == "sub").FirstOrDefault().Value ?? throw new Exception("No subject in token found."), ct) ?? throw new Exception("User not found.");
var chat = await chatById.LoadAsync(input.ChatId, ct) ?? throw new Exception("No chat found.");
var userChat = dbContext.UserChats.Where(uc => uc.ChatId == chat.Id && uc.UserId == user.Id).FirstOrDefault();
if (userChat != null)
{
var message = new Message
{
SenderId = user.Id,
ChatId = chat.Id,
Text = input.Text,
Timestamp = DateTime.Now
};
dbContext.Messages.Add(message);
await dbContext.SaveChangesAsync();
return(new SendMessagePayload(message));
}
else
{
throw new Exception("User is not a participant of the chat.");
}
}
public async Task <AddChatPayload> AddChatAsync(
AddChatInput input,
[ScopedService] ApplicationDbContext dbContext,
[Service] IHttpContextAccessor contextAccessor,
ChatByIdDataLoader chatById,
CancellationToken ct
)
{
var httpContext = contextAccessor.HttpContext ?? throw new ArgumentNullException($"{nameof(contextAccessor.HttpContext)} can't be null.");
var userId = httpContext.User.Claims.Where(uc => uc.Type == "sub").FirstOrDefault().Value;
var userIds = input.UserIds ?? throw new ArgumentNullException($"{nameof(input.UserIds)} can't be null.");
if (!userIds.Contains(userId))
{
userIds.Add(userId);
}
if (userIds.Count < 2)
{
throw new Exception("At least two users to create a chat.");
}
var chat = new Chat
{
Messages = new List <Message>()
};
// Check if there is an existing chat with all users
// if so return the existing chat
// Get all ids of chats where all users are inside
int[] chatIdsOfUsers = await dbContext.UserChats
.Where(uc => userIds.Contains(uc.UserId))
.GroupBy(uc => uc.ChatId, (g, r) => new
{
ChatId = g,
Count = r.Count()
})
.Where(p => p.Count == userIds.Count)
.Select(p => p.ChatId)
.ToArrayAsync();
if (chatIdsOfUsers != null && chatIdsOfUsers.Length > 0)
{
int[] existingChats = await dbContext.UserChats
.Where(uc => chatIdsOfUsers.Contains(uc.ChatId))
.GroupBy(uc => uc.ChatId, (g, r) => new
{
ChatId = g,
Count = r.Count()
})
.Where(p => p.Count == userIds.Count)
.Select(p => p.ChatId)
.ToArrayAsync();
if (existingChats != null && existingChats.Length > 0)
{
return(new AddChatPayload(await chatById.LoadAsync(existingChats[0], ct)));
}
}
// no existing chat found with all users so a new one will be created
dbContext.Chats.Add(chat);
var chatId = chat.Id;
List <UserChat> userChats = new List <UserChat>();
foreach (string uId in userIds)
{
userChats.Add(new UserChat
{
ChatId = chatId,
UserId = uId
});
}
chat.UserChats = userChats;
await dbContext.SaveChangesAsync();
return(new AddChatPayload(chat));
}
