[Story] EX: Send a warning to the caller making a legacy call

manuroe commented 3 weeks ago

Description

As a caller
I want to be warned the callee may not be able to answer to my legacy call with their EX app
So that I do not felt ghosted and I will retry using EX or an Element Call capable app

Acceptance criteria

Caller is aware by a notice in the timeline that the callee cannot answer because they are using EX
Callee EX app sends a notice in the timeline when receiving a legacy call
There is single notice per legacy call
~~The notice will be in the language of the callee EX app~~

Leads

Tech:
Design:

Size estimate

None

Dependencies

None

Out of scope

Nothing

Open questions

### Questions
- [x] Should EX automatically send the notice or do we want to display a popup asking for confirmation before sending like "Alice is trying to call you using legacy call. Do you want inform them they should use Element Call to reach you"? --> YES
- [x] Are we ok with "The notice will be in the language of the callee EX app"? --> NO

Subtasks

### Android

### iOS

### Web

### Other

Sign-off

Android

[ ] Design sign-off on completion
[ ] QA sign-off on completion
[ ] Product sign-off on completion

iOS

[ ] Design sign-off on completion
[ ] QA sign-off on completion
[ ] Product sign-off on completion

mxandreas commented 3 weeks ago

do we want to display a popup asking for confirmation before sending like "Alice is trying to call you using legacy call. Do you want inform them they should use Element Call to reach you"

Given, this is a temporary/workaround, I would keep it simple and without confirmation. I think it does not compromise privacy much, only exposes that one is using EX.

Are we ok with "The notice will be in the language of the callee EX app"?

I think that is fine; even hardcoding to English is also probably fine.

In terms of the message itself, I would propose something like:

"Bob may not be able to answer your call since you're using legacy calling. Please use Element X to reach them".

manuroe commented 3 weeks ago

We had a tech discussion about it. We are all aligned that we need a long term plan for the migration from lecacy calls to Element Calls BUT we cannot go quick to implement it, even with the band aid solution described in the issue. We tried to not overthinking but we kept raising concerns. It makes think we cannot converge in a better solution than what we have now in the 1 or 2 days of work allocate for this.

From the meeting: Problems:

Privacy concern: the app is going to automatically send message in place of the callee
Several clients can generate several notices, poluting the timeline
Privacy concern: it will advertise the app the callee is using
Tech: we need to manage timeline resets. A stupid and simple implementation will create bugs that we are going to manage

Discussed options:

Implement this-auto sending in the SDK where it manages call notifications
Another user flow: The user taps the incoming call notification -> the app opens on the room -> the app sends the notice
- Problem: there is no notification if the user is already looking at the room
Ideally: we need MSC work to address it properly like having a negotiation setup step in the call flow. But it is going to budgeted time by a lot
EX could send m.call.reject to say "sorry, can't answer now as you need to speak MatrixRTC". We then make a trivial change to the legacy apps to display that appropriately
For group calls, we could display the Jitsi link in the timeline. It implies to add Widget API support in EX.

manuroe commented 3 weeks ago

The current solution is that the callee gets a notification and a timeline item saying "Call in progress (unsupported)". Then, the callee can they interact with the caller to find a way to communicate.

Another option could be to iterate on the wording on this not useful information in the timeline. The copy could invite the callee to engage and chat with the caller. Doing so, we could revisit the mechanism that computes the call state in that timeline item. It is not working well.

bmarty commented 3 weeks ago

Note: if by "notice" we're talking about m.notice msgtype, we will need to handle https://github.com/element-hq/element-x-android/issues/3636 as well on Android.

davidmehren commented 3 weeks ago

Instead of just showing "Call in progress (unsupported)", could you not display the Jitsi link, so the callee may join using the Jitsi app or their browser?

ara4n commented 3 weeks ago

How about we spec m.call.reject code which EX can send to say "sorry, can't answer now as you need to speak MatrixRTC". We then make a trivial change to the legacy apps to display that appropriately?

manuroe commented 3 weeks ago

Instead of just showing "Call in progress (unsupported)", could you not display the Jitsi link, so the callee may join using the Jitsi app or their browser?

Thanks for the hint. We were focused on the DM case but we could definitely used the Jitsi link for group calls. We just™️ need to make Element X support the widget API :/

How about we spec m.call.reject code which EX can send to say "sorry, can't answer now as you need to speak MatrixRTC". We then make a trivial change to the legacy apps to display that appropriately?

Oh, yes. @bmarty raised it too. I added it to the list

neilisfragile commented 1 week ago

Draft MSC https://github.com/matrix-org/matrix-spec-proposals/blob/matthew/msc4220/proposals/4220-call-reject-locally.md

element-hq / element-meta