ui: reconnect call (#7711)

* Update Call.hs

* Update Internal.hs

* add reconnecting string

* Update WebRTC.kt

* desktop: show reconnecting state, keep call duration

* android keep connection time correct wiith adding reconnecting

* Update CallTypes.swift add reconnecting status on IOS

* Update WebRTC.swift add reconnecting

* add reconnecting and make sure call duration is correct

* Update call.ts

* core: regenerate call.js from call.ts

* Update Call.hs revert call status change

minimization

* Update Internal.hs rever to minimize changes

* Update CallTypes.swift minimize changes

* Update WebRTC.kt minimize changes

* Update CallView.desktop.kt desktop shows reconnecting without sending to core

* Update CallView.android.kt show reconnecting without sending it to the core

* Update ActiveCallView.swift show reconnecting to ui without sending to core

* Update CallView.desktop.kt add reconnecting sound on reconnect

* Update CallView.android.kt add reconnecting sound

* Update ActiveCallView.swift play reconnecting sound when reconnecting

* Update RecAndPlay.desktop.kt

* rebuild

* refactor

* build

* android, desktop: restart ICE to reconnect calls

* ios: restart ICE to reconnect calls

* webrtc: add call reconnection e2e tests

* android, desktop: fix lost call commands

---------

Co-authored-by: GuavaGoat <320862384+GuavaGoat@users.noreply.github.com>
Co-authored-by: Evgeny Poberezkin <evgeny@poberezkin.com>
Co-authored-by: Evgeny @ SimpleX Chat <259188159+evgeny-simplex@users.noreply.github.com>

apps/multiplatform/product/flows/calling.md

@@ -99,6 +99,7 @@ Both platforms share a common signaling flow through the Haskell core API.
 ```
 Outgoing: WaitCapabilities -> InvitationSent -> OfferSent -> AnswerReceived -> Negotiated -> Connected -> Ended
 Incoming: InvitationAccepted -> OfferReceived -> Negotiated -> Connected -> Ended
+Reconnection: Connected -> Reconnecting -> Connected | Ended
 ```
 
 | State | Description |
@@ -111,8 +112,17 @@ Incoming: InvitationAccepted -> OfferReceived -> Negotiated -> Connected -> Ende
 | `AnswerReceived` | Caller received SDP answer |
 | `Negotiated` | ICE negotiation complete |
 | `Connected` | Media flowing |
+| `Reconnecting` | Connection lost, waiting for ICE restart |
 | `Ended` | Call terminated |
 
+### 3.1 Reconnection
+
+1. A connected call loses its WebRTC connection, e.g. when the device switches between Wi-Fi and mobile network.
+2. The WebRTC engine reports `"reconnecting"` connection state; the app shows "reconnecting…" and plays the connecting sound. This state is not reported to the core, and `connectedAt` is kept, so call duration continues.
+3. The callee's WebRTC engine (the party that sent the initial offer) restarts ICE every 10 seconds, sending the new offer in `WCallResponse.Ice` with `session` via `apiSendCallExtraInfo`. The caller answers the same way.
+4. When the connection is restored, the call returns to `Connected` and the sound stops.
+5. If the connection is not restored in 30 seconds, the call ends as disconnected. Clients without ICE restart support ignore the restart offer, so the call ends in this case.
+
 ---
 
 ## 4. Ending a Call
@@ -184,7 +194,7 @@ Incoming: InvitationAccepted -> OfferReceived -> Negotiated -> Connected -> Ende
 | `apiRejectCall(rh, contact)` | Reject incoming call |
 | `apiSendCallOffer(rh, contact, rtcSession, rtcIceCandidates, media, capabilities)` | Send SDP offer |
 | `apiSendCallAnswer(rh, contact, rtcSession, rtcIceCandidates)` | Send SDP answer |
-| `apiSendCallExtraInfo(rh, contact, rtcIceCandidates)` | Send additional ICE candidates |
+| `apiSendCallExtraInfo(rh, contact, rtcSession, rtcIceCandidates)` | Send additional ICE candidates, or ICE restart offer/answer |
 | `apiEndCall(rh, contact)` | End active call |
 | `apiCallStatus(rh, contact, status)` | Report WebRTC connection status |
 

apps/multiplatform/product/views/call.md

@@ -71,8 +71,8 @@ Sound: `SoundPlayer.start()` plays ringtone while banner is visible (unless call
 | 1. Capabilities | `WCallResponse.Capabilities` | Local capabilities reported; `apiSendCallInvitation()` called |
 | 2. Offer | `WCallResponse.Offer` | SDP offer + ICE candidates sent via `apiSendCallOffer()` |
 | 3. Answer | `WCallResponse.Answer` | SDP answer + ICE candidates sent via `apiSendCallAnswer()` |
-| 4. ICE | `WCallResponse.Ice` | Additional ICE candidates exchanged via `apiSendCallExtraInfo()` |
-| 5. Connection | `WCallResponse.Connection` | WebRTC connection state changes; `CallState.Connected` set on success |
+| 4. ICE | `WCallResponse.Ice` | Additional ICE candidates, and ICE restart offer/answer in `session`, exchanged via `apiSendCallExtraInfo()` |
+| 5. Connection | `WCallResponse.Connection` | WebRTC connection state changes; `CallState.Connected` set on success, `CallState.Reconnecting` when a connected call loses connection |
 | 6. Connected | `WCallResponse.Connected` | Connection info (relay/direct) stored in `call.connectionInfo` |
 | 7. PeerMedia | `WCallResponse.PeerMedia` | Remote party media source changes (mic, camera, screen) |
 | 8. Media control | `WCallCommand.Media` | Toggle local media sources (mic, camera, screen audio/video) |
@@ -90,14 +90,15 @@ Sound: `SoundPlayer.start()` plays ringtone while banner is visible (unless call
 | `OfferReceived` | Callee received SDP offer |
 | `AnswerReceived` | Caller received SDP answer |
 | `Negotiated` | ICE negotiation complete |
-| `Connected` | WebRTC media flowing; `connectedAt` timestamp set |
+| `Connected` | WebRTC media flowing; `connectedAt` timestamp set on the first connection |
+| `Reconnecting` | Connection lost; "reconnecting…" shown while ICE restarts, call ends after 30 seconds without connection |
 | `Ended` | Call terminated |
 
 ### Call Sounds
 
 | Sound | Trigger |
 |---|---|
-| Connecting sound | `CallSoundsPlayer.startConnectingCallSound()` after invitation sent |
+| Connecting sound | `CallSoundsPlayer.startConnectingCallSound()` after invitation sent, and while reconnecting |
 | In-call sound | `CallSoundsPlayer.startInCallSound()` when delivery receipt received |
 | Ringtone | `SoundPlayer.start()` for incoming calls |
 | End vibration | `CallSoundsPlayer.vibrate()` on call end (if was connected) |