---
type: architecture
title: Application state and event handling
description: How the App struct in src/app.rs holds UI state, routes AppEvent values (keys, WhatsApp, AI replies, image descriptions, reply timers, web panel, configuration reloads, relink outcomes), handles function keys (including F8 relink), the list filter and chat deletion, toggles global and per-chat autoreply, and runs background tasks.
tags: [app, state, events, keybindings, tokio, web-panel, relink, config-reload]
verified:
  - by: openwiki/0.7.2
    at: 2026-10-23T21:26:24.156Z
sources:
  - id: openwiki-source-9fec9d1af408501c9c455161
    resource: repo://src/app.rs
generated: { by: "claude-code", at: "2026-10-23T21:26:24.156Z" }
---

# Application state and event handling

`src/app.rs` owns the whole application state. The event loop described in
[Runtime and event loop](runtime-and-event-loop.md) feeds every input into
`App::handle_event`, and the [terminal UI](terminal-ui.md) renders the public
fields of `App` after each event. `App` is the only component that mutates the
[history store](../concepts/history-store.md) in response to user, WhatsApp
and [web panel](../integrations/web-control-panel.md) activity.

## Events

`AppEvent` (`src/app.rs:106-141`) is the single message type of the main channel:

| Variant | Producer | Meaning |
|---|---|---|
| `Key(KeyEvent)` | input thread | A key press (release/repeat events are filtered out upstream). |
| `Redraw` | input thread | Terminal resized; nothing to change, just redraw. |
| `Wa(WaEvent)` | WhatsApp forwarder | An event from the [WhatsApp client](../integrations/whatsapp-client.md). |
| `AiReply { chat_jid, result }` | AI background task | `Reply::Text`, `Reply::NoReply` (model called the `no_reply` tool) or an error string. |
| `ImagesDescribed { target, results }` | image description task | One description (or error) per image of a chat, keyed by message id; `target` says whether to answer the chat afterwards. |
| `ReplyDue { chat_jid }` | reply timer task | The reply delay of a chat has elapsed. |
| `Sent { chat_jid, text, is_ai, result }` | send background task | Outcome of a text send. |
| `Web(WebRequest)` | `wh-web` thread | A command from the [web control panel](../integrations/web-control-panel.md) with a reply channel. |
| `ConfigReloaded(Result<Box<Config>, String>)` | configuration watcher task | A configuration file changed: the reloaded `Config` or the load error. |
| `Relinked(Result<(), String>)` | relink task | Outcome of a relink: the new unpaired session started, or the error. |

`handle_event` (`src/app.rs:293-317`) dispatches each variant; after an
`AiReply` it always calls `finish_reply` to end the chat's pending state. Only
fatal history (SQLite) errors propagate as `Err`; every other failure is turned
into a `status` text shown in the footer.

## State

`App` (`src/app.rs:188-239`) exposes UI fields read by the renderer: `screen`,
`qr_code`, `focus`, `list_mode`, `chats`, `contacts`, `selected`, `filter`,
`open_chat`, `open_chat_name`, `open_chat_autoreply`, `global_autoreply`,
`messages`, `input`, `status` and `should_quit`. Private fields hold the
`History`, the `Config`, an optional `AiClient`, the autoreply `ReplyGate`,
the WhatsApp handle and a clone of the event sender, plus the reply
bookkeeping:

| Field | Purpose |
|---|---|
| `pending_images` | images received by chats with a scheduled reply, per chat, in arrival order |
| `backlog_images` | images delivered with offline messages, kept until the catch-up runs |
| `describing` | message ids whose image description is in progress (never described twice) |
| `answered_up_to` | per chat, the id of the last message in the context of the reply in progress |
| `own_jids_known`, `catch_up_done` | one-shot flags for own JIDs and the startup catch-up |
| `pending_delete` | the chat awaiting a deletion confirmation |
| `pending_relink` | a first F8 press awaits the second one that confirms the relink |
| `relinking` | a relink is running; further relink requests are ignored until it ends |

- `Screen` (`src/app.rs:151-157`): `Connecting` → `Pairing` (QR shown) → `Main`.
- `Focus` (`src/app.rs:159-164`): `List` or `Input`.
- `ListMode` (`src/app.rs:166-171`): `Chats` or `Contacts`.

`App::new` (`src/app.rs:246-286`) builds the AI client with `build_ai`, loads
chats, contacts and the persisted global autoreply flag from history, starts on
`Connecting` with list focus in chat mode, an empty filter and no pending
deletion or relink, and creates the `ReplyGate` with the current time, so that
backlog messages are never auto-answered live.

`build_ai` (`src/app.rs:1534-1542`) returns no client when the system prompt
(`SOUL.md`, see [Configuration](../operations/configuration-and-data.md)) is
missing — status `AI non configurata: imposta openai_api_key in config.toml e
il prompt in SOUL.md` — and reports a client build error with the
`AI non disponibile` prefix.

## Configuration reload

The [configuration watcher](../operations/configuration-and-data.md#live-reload)
sends `ConfigReloaded` when `config.toml`, `SOUL.md` or `VISION.md` change.
`apply_reloaded_config` (`src/app.rs:388-400`) keeps the current configuration
and shows `Configurazione non ricaricata: <error>` when the load failed;
otherwise it replaces `config`, rebuilds the AI client with `build_ai` (replies
already running keep the client they were started with) and shows
`Configurazione ricaricata`, or the `build_ai` status when the AI is not
configured or unavailable. Later replies therefore use the new prompt, model,
delays and retries without a restart.

## WhatsApp events

`handle_wa_event` (`src/app.rs:406-429`):

- `Qr` → switch to `Pairing` and store the QR payload.
- `Connected` → switch to `Main`, clear the QR, status `Connesso`, refresh own JIDs.
- `Disconnected` / `Error` → update `status` only.
- `LoggedOut` → back to `Connecting`, status `Sessione scollegata`.
- `OfflineSyncCompleted` → `on_offline_sync_completed`, the startup catch-up
  (see below).
- `Contact` → `on_contact`: upsert the contact, reload contacts and chats and
  refresh the open chat name (`src/app.rs:435-443`).
- `Message { message, image }` → `on_message` (`src/app.rs:450-459`).

`on_message` saves the message and stops immediately when
`History::save_message` reports a duplicate, so history sync replays never
trigger UI reloads or autoreplies twice. New messages reload the chat list, the
open conversation and then go through `maybe_autoreply` (see
[AI autoreply](../workflows/ai-autoreply.md)).

Own JIDs are fetched by `refresh_own_jids` (`src/app.rs:797-804`); the list is
empty while the device is not paired (or no session is running during a
relink), so the refresh is retried later (`own_jids_known` stays false until it
succeeds).

## Relink

F8 (twice) and the web panel's `Relink` command replace the WhatsApp session
with a new unpaired one; the full flow is in
[WhatsApp relink and pairing](../workflows/relink-and-pairing.md). In `App`:

- `request_relink` (`src/app.rs:361-369`) cancels a pending chat deletion; the
  first F8 sets `pending_relink` and shows
  `Cancellare la sessione WhatsApp e rifare l'abbinamento? F8 conferma, Esc annulla`,
  the second calls `start_relink`.
- `cancel_pending_relink` (`src/app.rs:375-381`) clears the flag on any other
  key and shows `Nuovo abbinamento annullato`.
- `start_relink` (`src/app.rs:326-341`) is a no-op while `relinking`;
  otherwise it switches to `Connecting`, clears the QR, shows
  `Cancellazione della sessione in corso...`, resets `own_jids_known` (the new
  pairing may be another account) and spawns a task that runs
  `WaHandle::relink` and sends `Relinked`. The web command calls it directly,
  without the two-press confirmation (the browser asks instead).
- `finish_relink` (`src/app.rs:348-354`) clears `relinking` and shows
  `Sessione cancellata: scansiona il nuovo QR` or
  `Nuovo abbinamento fallito: <error>`; the screen then follows the new
  session's `Qr` / `Connected` events.

## Autoreply orchestration

A chat is "enabled" when the global autoreply is on **or** its per-chat flag
is on (`autoreply_enabled`, `src/app.rs:642-644`). `ai_setup`
(`src/app.rs:749-751`) returns nothing, and so stops every path, when the AI
client or the system prompt is missing. The full workflow is in
[AI autoreply](../workflows/ai-autoreply.md); the state machine in `App` is:

- **Schedule** — `maybe_autoreply` (`src/app.rs:468-483`) calls
  `schedule_reply` when `ReplyGate::should_schedule` allows it: the chat is
  marked pending and `spawn_reply_timer` (`src/app.rs:1345-1350`) emits
  `ReplyDue` after `reply_delay_seconds`. A chat already pending gets no second
  timer, so messages arriving meanwhile are answered together. An image sent by
  an allowed sender in an enabled chat is kept by `keep_image`
  (`src/app.rs:501-515`): in `pending_images` for a pending chat, in
  `backlog_images` for an offline image before the catch-up, or described at
  once without reply (`describe_late_image`) after it.
- **Reply due** — `handle_reply_due` (`src/app.rs:539-545`) takes the kept
  images and, if the chat is still pending, calls `prepare_reply`
  (`src/app.rs:556-568`). `reply_context` (`src/app.rs:652-664`) returns
  nothing when the autoreply was disabled, the AI is missing, the chat is
  empty or its last message was written by hand by the owner; then the
  pending state ends. Otherwise images still lacking a description go to
  `spawn_descriptions` (reply follows on `ImagesDescribed`), or `start_reply`
  runs at once.
- **Descriptions** — `handle_images_described` (`src/app.rs:591-614`) stores
  each description whose message still exists with
  `History::save_image_description`, sets one status for failures
  (`Descrizione immagine fallita (N): <first error>`) and, when `then_reply`
  holds and the chat is still pending, starts the reply.
- **Start** — `start_reply` (`src/app.rs:771-790`) records the last context
  message in `answered_up_to`, marks own mentions, reads the chat name and the
  stored image descriptions, builds the turns and calls `spawn_ai_request`.
- **Finish** — `finish_reply` (`src/app.rs:622-636`) clears the pending state
  and `answered_up_to`; if a newer message that passes `should_schedule`
  arrived after the answered one, it schedules a new reply (keeping its
  images), otherwise it drops the kept images.
- **Startup catch-up** — `on_offline_sync_completed` (`src/app.rs:688-694`)
  runs `catch_up` once per process (`catch_up_done`). `catch_up`
  (`src/app.rs:704-724`) asks `catch_up_chats` (`src/app.rs:731-743`) for the
  enabled chats (all chats when the global autoreply is on) whose latest
  stored message passes `ReplyGate::catch_up_due` within `catch_up_seconds`,
  marks each pending and calls `prepare_reply` with its offline images (no
  reply delay); the status becomes `Risposte di recupero: N` when N > 0.

## Key bindings

Commands use function keys (`src/app.rs:23-32`); `handle_key`
(`src/app.rs:884-929`) dispatches them:

| Key | Where | Action |
|---|---|---|
| F10 | any screen | Quit (`should_quit = true`). |
| F8 | any screen | First press asks to delete the WhatsApp session and pair again; second press confirms (see [Relink](#relink)). |
| Esc | after a first F8 | Cancels the pending relink (the key is consumed). |
| F2 | main screen, any focus | Switch chat list / contact list; selection resets to 0, filter kept. |
| F3 | main screen | Toggle autoreply for the focused chat: the selected row with list focus, the open chat with input focus. |
| F4 | main screen, any focus | Toggle the global autoreply ("AI tutte"). |
| Tab | main screen | Switch focus between list and input. |
| Up / Down | list focus | Move selection by one row, clamped to the filtered list. |
| PageUp / PageDown | list focus | Move selection by 10 rows (`LIST_PAGE_ROWS`), clamped. |
| Home / End | list focus | Jump to the first / last row. |
| Enter | list focus | Open the selected chat or contact. |
| characters / Backspace | list focus | Edit the list filter; selection resets to 0. |
| Esc | list focus | Clear the filter (or cancel a pending deletion). |
| Delete (Canc) | list focus, chat mode | Ask to delete the selected chat; a second Delete confirms. |
| characters / Backspace | input focus | Edit the input line. |
| Esc | input focus | Return focus to the list. |
| Enter | input focus | Send the trimmed input to the open chat. |

F10 and F8 are checked first, on every screen. Any other key cancels a
pending relink; an Esc that does so is consumed, every other key then
continues normally. Non-main screens ignore everything else. Ctrl chords are
swallowed (they cancel a pending deletion and do nothing else) so they never
type into the input or the filter; `is_command` (`src/app.rs:1592-1594`)
treats Ctrl as a command only when Alt is not held, because Windows reports
AltGr as Ctrl+Alt (needed for `@`, `#`, `€` on the Italian layout). Switching
list mode with F2 also makes the event loop repaint the whole terminal (see
[Runtime and event loop](runtime-and-event-loop.md)).

### List filter

Typing while the list has focus edits `filter` (`handle_list_key`,
`edit_filter`, `src/app.rs:937-973`). `visible_chats` / `visible_contacts`
(`src/app.rs:1048-1058`) keep the entries whose name contains the filter,
case-insensitively (`matches_filter`, `src/app.rs:1289-1291`); selection,
opening, F3 and deletion all work on the filtered list.

### Local chat deletion

`request_delete` (`src/app.rs:992-1009`) works only in chat mode: the first
Delete stores the selected chat in `pending_delete` and shows
`Eliminare la chat <name>? Canc conferma, Esc annulla`; a second Delete on
the same chat calls `confirm_delete` (`src/app.rs:1016-1031`), which removes
the chat from the history (messages, image descriptions and row; no WhatsApp
call), drops its pending reply, kept images and answered snapshot, closes it
if open and shows `Chat <name> eliminata`. Any other key (Tab, F2, F3, F4, F8,
list keys, Ctrl chords) cancels the pending deletion with
`Eliminazione annullata` (`cancel_pending_delete`, `src/app.rs:979-985`).

### Opening and toggling

`selected_jid` (`src/app.rs:1221-1232`) returns the JID on the selected row of
the active filtered list (chat or contact), or nothing when it is empty.
`open_selected` (`src/app.rs:1205-1219`) uses it to load display name,
per-chat autoreply flag and the last `MESSAGES_SHOWN` (200) messages, then
moves focus to the input. The `reload_*` helpers (`src/app.rs:1249-1274`) keep
`selected` inside the active filtered list.

`toggle_autoreply` (F3, `src/app.rs:1101-1116`) picks the target from the
focus — `selected_jid` with list focus, `open_chat` with input focus — and
delegates to `toggle_chat_autoreply` (`src/app.rs:1124-1137`), which always
allows disabling and updates `open_chat_autoreply` when the target is the open
chat. Enabling goes through `can_enable_autoreply`
(`src/app.rs:1549-1557`), which first requires an AI client and then a chat
accepted by `supports_autoreply` (private chats and groups; broadcasts,
status and newsletters are refused with
`Autoreply disponibile solo nelle chat private e nei gruppi`). The flag is
persisted with `History::set_autoreply` and the status shows
`Autoreply ON|OFF per <name>`.

`toggle_global_autoreply` (F4, `src/app.rs:1192-1203`) refuses to enable
without an AI client (`STATUS_AI_NOT_CONFIGURED`), persists the flag with
`History::set_global_autoreply`, updates `global_autoreply` and shows
`Autoreply globale ON|OFF`. Disabling is always allowed.

## Web panel requests

`handle_web_request` (`src/app.rs:1139-1156`) applies a `WebCommand` and then
always sends back a `WebState` snapshot on the request's oneshot channel:

- `State` → nothing, just the snapshot;
- `ToggleGlobal` → `toggle_global_autoreply` (same rules as F4);
- `ToggleChat(jid)` → `toggle_web_chat` (`src/app.rs:1163-1169`): if the JID is
  not among the panel's chats the status becomes `Chat non trovata`,
  otherwise `toggle_chat_autoreply` (same rules as F3);
- `Relink` → `start_relink` (no second confirmation; ignored while a relink runs);
- `Quit` → `should_quit = true`.

`web_state` (`src/app.rs:1171-1184`) returns the global flag, the status line,
`web_chats` (`src/app.rs:1575-1585`) — the TUI chat list in the same order,
restricted to chats that support autoreply — the current screen as
`connecting` / `pairing` / `main` (`web_screen`, `src/app.rs:1563-1569`) and,
while a QR payload is stored, the QR code rendered as SVG by `web::qr_svg`. See
[Web control panel](../integrations/web-control-panel.md).

## Sending and background tasks

All network work runs in tokio tasks that report back through the event
channel; `send_event` ignores a closed channel because that only happens on
shutdown (`src/app.rs:1335-1338`).

- `submit_input` (`src/app.rs:1080-1088`) ignores blank input or no open chat,
  clears the input and calls `spawn_send` with `is_ai: false`.
- `spawn_send` (`src/app.rs:1518-1527`) calls `WaHandle::send_text` and emits
  `Sent`; during a relink no session is running, so sends fail with a send
  error.
- `handle_sent` (`src/app.rs:858-882`) stores a successful send as a
  `from_me` message (with `is_ai` preserved) and reloads the views; a failure
  sets `Invio fallito: …`.
- `spawn_ai_request` (`src/app.rs:1359-1370`) runs the text completion in one
  task and waits for it in another, so `AiReply` is always emitted — even when
  the request task panics — and the chat never stays pending.
- `spawn_image_descriptions` (`src/app.rs:1381-1404`) runs one task per image
  in parallel (download with up to 3 attempts and a 60 s timeout each, then
  `AiClient::describe_image`) and a collector task that emits a single
  `ImagesDescribed`; a failed image does not stop the others and the bytes
  stay in memory.
- `handle_ai_reply` (`src/app.rs:812-818`) shows
  `AI: nessuna risposta necessaria` for `Reply::NoReply`, `Errore AI: …` for
  an error, and passes text to `send_ai_reply_if_enabled`
  (`src/app.rs:826-839`), which sends it only if the chat is still enabled and
  the owner did not answer by hand meanwhile (`owner_answered_meanwhile`);
  otherwise it shows `Risposta AI scartata: autoreply disattivato` or
  `Risposta AI scartata: hai già risposto`.
- The relink task (see [Relink](#relink)) runs `WaHandle::relink` and emits
  `Relinked`.

## Tests

Unit tests at `src/app.rs:1596` onward cover `can_enable_autoreply` (private,
self-chat LID, groups allowed; broadcasts/newsletters and missing AI refused),
`web_chats` filtering and order, `vision_applies`,
`select_images_to_describe` (last five, skip known and out-of-context),
`arrived_after`, `manual_reply_after`, `description_failure_status`,
`matches_filter`, selection clamping/stepping and page steps, the toggle
helpers, `is_command` and the fixed function-key codes (F2, F3, F4, F10; F8 is
not part of that check). Relink, configuration reload and F3 targeting have no
`App`-level tests. See [Unit tests](../testing/unit-tests.md).