Add ability to see a timestamp when the message was received / read

[or-else]

Is your feature request related to a problem? Please describe.

It maybe useful to see when the message was delivered to each recipient and when it was read.

Describe the solution you'd like

Add message delivery info screen.

[Chr728]

was the feature added or do you want me to add this feature? if possible please give details of what is needed to add.

[or-else]

It's not a simple feature. Here is a high-level outline.

Tinode client apps consider a message read when the message appears on the screen for ~500ms. When the message with seq=X is read the client app sends a note to the server that all messages with seq <= X have been read. It does not mean that all these messages appeared on the screen: if the user has 100 unread messages, only 10 or so would fit on the screen but all 100 would be marked as read.

The server records that user U read all messages with seq <= X, but it does not record the time when specific seq was read.

In order to implement this feature correctly you have to store the timestamp of each read receipt for each user. I believe it requires a separate DB table, something like topicID, seq, userID, timestamp. Then this information has to be passed from the server to the client which probably requires modifications to the wire protocol.

It's possible to implement this feature half-way by storing the timestamp of the last read receipt for each user and saving the corresponding timestamp on the client. This would give an approximation of when the message was read.

Overall the feature looks very heavy for the marginal value it provides.

[or-else]

@Chr728 If you would like a starter project, this would be a good one: #707
It's relatively simple, well isolated and useful.

[Chr728]

@or-else will try looking at #651 first then if possible will look into #707. thank you