Struct UiState 

pub struct UiState {

    pub mode: UiMode,
    pub input_buffer: String,
    pub input_cursor: usize,
    pub attachments: Vec<Attachment>,
    pub attachment_focused: bool,
    pub attachment_selected: usize,
    pub chat_scroll: usize,
    pub palette_filter: String,
    pub palette_cursor: Option<usize>,
    pub queued_messages: VecDeque<String>,
    pub last_title_dispatched: Option<String>,
    pub pending_msgs: VecDeque<Msg>,
    pub input_history_cursor: Option<usize>,
    pub history_draft: String,
    pub mouse_scroll_accum: i32,
}

All UI-only state. Things in UiState never affect what gets sent to the model — only what the user sees.

Fields

mode: UiMode

input_buffer: String

input_cursor: usize

Byte position within input_buffer. The reducer normalizes to a UTF-8 char boundary on every mutation via floor_char_boundary, so widgets can slice safely.

attachments: Vec<Attachment>

Pending image pastes queued for the next user message.

attachment_focused: bool

When true, keyboard focus is on the attachment bar (up arrow from input moves focus up here; Esc returns focus to input).

attachment_selected: usize

Highlighted attachment index when focused. Ignored when attachment_focused is false.

chat_scroll: usize

Scroll offset for the chat pane.

palette_filter: String

When the slash-palette is open, this holds the filter prefix (typed after the leading /) so the palette widget can re-query the registry.

palette_cursor: Option<usize>

When Some(i), the palette has a highlighted row. None = closed / not showing.

queued_messages: VecDeque<String>

Messages the user typed while a turn was in flight. The reducer pops the oldest and auto-submits on a successful StreamDone. FIFO order.

last_title_dispatched: Option<String>

Last terminal title dispatched via Cmd::SetTerminalTitle. Arms that change session.conversation.title consult this and emit a fresh SetTerminalTitle only on diff.

pending_msgs: VecDeque<Msg>

Follow-up Msgs the reducer has queued for re-entry. The outer update() drains this after each single-step call so a handler can emit a synthetic event (e.g. Enter-on-slash queuing Msg::Slash(cmd)) without self-invoking the reducer. Bounded drain depth guards against runaway loops.

input_history_cursor: Option<usize>

Up-arrow history navigation cursor into session.conversation.input_history. None = not navigating (input_buffer is whatever the user typed). Some(i) = currently displaying history entry at index i from the END (0 = newest).

history_draft: String

Whatever the user had typed before hitting Up. Preserved so stepping past the newest history entry with Down restores the partial input unchanged. Cleared on any non-nav key.

mouse_scroll_accum: i32

Running accumulator for mouse-wheel scroll events (F13). The reducer adds the delta here on Msg::MouseScroll; the render layer compares against its last-seen snapshot and applies the diff to the chat pane’s ChatState. This keeps the reducer pure — it doesn’t touch render-layer state, it just publishes an intent. i32 wraps at ~2 billion scrolls (never).

Trait Implementations

impl Clone for UiState

fn clone(&self) -> UiState

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for UiState

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for UiState

fn default() -> UiState

Returns the “default value” for a type.