/// <summary>
/// Starts a new conversation with the given user by adding their message to the database.
/// returns the Id of the newly created conversation. Increments the unread count of the
/// user the message was sent to.
/// </summary>
public async Task<int> StartConversation(int from, int to, string subject, string message)
{
var db = new OkbDbContext();
Message msg;
ConversationMap mapMe, mapOther;
//// New conversation
var conv = new Conversation { Subject = subject };
db.Conversations.Add(conv);
msg = new Message
{
Conversation = conv,
From = from,
MessageText = message,
Timestamp = DateTime.Now
};
db.Messages.Add(msg);
//My copy of the conversation
mapMe = new ConversationMap
{
Conversation = conv,
LastMessage = msg,
Other = to,
ProfileId = from,
HasBeenRead = true,
HasReplies = false
};
db.ConversationMap.Add(mapMe);
//Other's copy of the conversation
mapOther = new ConversationMap
{
Conversation = conv,
LastMessage = msg,
Other = from,
ProfileId = to,
HasBeenRead = false,
HasReplies = true
};
db.ConversationMap.Add(mapOther);
await db.SaveChangesAsync();
//Everything OK - we can increment the unread count
IncrementUnreadCount(to);
return conv.Id; //return new conversation Id
}
/// <summary>
///
/// Adds a new message to the Messages table. Creates a new converation if necessary.
/// - Updates the LastMessage to point to new message in the ConversationMap table.
/// - Sets the HasBeenRead and HasReply flags
///
/// Returns the conversation Id the message was added to
/// </summary>
public async Task<int> AddMessageAsync(int from, int to, string text, int? convId = null)
{
var db = new OkbDbContext();
Message msg;
ConversationMap mapMe, mapOther;
if (convId==null)
{
//// New conversation
var conv = new Conversation { Subject = "Hi" };
db.Conversations.Add(conv);
msg = new Message
{
Conversation = conv,
From = from,
MessageText = text,
Timestamp = DateTime.Now
};
db.Messages.Add(msg);
//My copy of the conversation
mapMe = new ConversationMap
{
Conversation = conv,
LastMessage = msg,
Other = to,
ProfileId = from,
HasBeenRead = true,
HasReplies = false
};
db.ConversationMap.Add(mapMe);
//Other's copy of the conversation
mapOther = new ConversationMap
{
Conversation = conv,
LastMessage = msg,
Other = from,
ProfileId = to,
HasBeenRead = false,
HasReplies = true
};
db.ConversationMap.Add(mapOther);
await db.SaveChangesAsync();
return conv.Id; //return new conversation Id
}
//// Add to existing conversation
msg = new Message
{
ConversationId = (int)convId,
From = from,
MessageText = text,
Timestamp = DateTime.Now
};
db.Messages.Add(msg);
//Update last message in conversation
mapMe = db.ConversationMap.Find(from, convId);
mapMe.HasBeenRead = true;
mapOther = db.ConversationMap.Find(to, convId);
mapOther.HasBeenRead = false;
if (!mapMe.HasReplies || !mapOther.HasReplies)
{
//Conversation doesn't have replies. Check if this message is a reply
//and set flag accordingly.
if(mapMe.LastMessage.From != from)
{
//the last message isn't from me
mapMe.HasReplies = true;
mapOther.HasReplies = true;
}
}
mapMe.LastMessage = msg;
mapOther.LastMessage = msg;
await db.SaveChangesAsync();
return (int)convId; //return passed in conversation Id
}
/// <summary>
///
/// Deletes the conversation for a user from ConversationMap. Decrements the
/// message count for the user by the number of messages in conversation.
///
/// </summary>
public async Task DeleteConversationAsync(int id, int convId)
{
var db = new OkbDbContext();
//TODO: Get number of messages in conversation
//var query = from msg in db.Messages.AsNoTracking()
// where msg.ConversationId == convId
// select msg;
//var count = query.Count();
//Delete conversation
var toDelete = new ConversationMap { ConversationId = convId, ProfileId = id };
db.ConversationMap.Attach(toDelete);
db.ConversationMap.Remove(toDelete);
//TODO: Decrement message count for user
await db.SaveChangesAsync();
}
/// <summary>
/// Reply to an existing conversation. We don't need the "to" field since we only
/// store the "from" field for each message. Increments the unread count for the
/// user sent to if the message was previously unread.
/// </summary>
public async Task Reply(int from, int convId, string message)
{
var db = new OkbDbContext();
Message msg;
ConversationMap mapMe, mapOther;
bool incUnreadFlag = false;
//// Add to existing conversation
msg = new Message
{
ConversationId = convId,
From = from,
MessageText = message,
Timestamp = DateTime.Now
};
db.Messages.Add(msg);
//Update last message in conversation
mapMe = db.ConversationMap.Find(from, convId);
mapMe.HasBeenRead = true;
mapOther = db.ConversationMap.Find(mapMe.Other, convId);
if (mapOther==null)
{
//conversation doesn't exist for other user - they deleted it
mapOther = new ConversationMap
{
ConversationId = convId,
ProfileId = mapMe.Other,
Other = from,
HasBeenRead = false,
HasReplies = true
};
db.ConversationMap.Add(mapOther);
incUnreadFlag = true;
}
//Increment unread count for "to" user if convesation was previously unread
if (mapOther.HasBeenRead)
{
incUnreadFlag = true;
}
mapOther.HasBeenRead = false;
mapOther.HasBeenEmailed = false;
if (!mapMe.HasReplies || !mapOther.HasReplies)
{
//Conversation doesn't have replies. Check if this message is a reply
//and set flag accordingly.
if (mapMe.LastMessage.From != from)
{
//the last message isn't from me
mapMe.HasReplies = true;
mapOther.HasReplies = true;
}
}
mapMe.LastMessage = msg;
mapOther.LastMessage = msg;
await db.SaveChangesAsync();
//do this last in case we have any db errors
if (incUnreadFlag)
{
IncrementUnreadCount(mapMe.Other);
}
}