claudbg/.beans/claudbg-nq36--tui-app-state-model-and-screen-enum.md

title	status	type	priority	created_at	updated_at	parent	blocked_by
TUI: app state model and screen enum	completed	task	normal	2026-03-30T04:45:19Z	2026-03-30T16:40:31Z	claudbg-i6l2	claudbg-78xt

Define the central AppState struct and Screen enum that drive the entire TUI.

Types to define (src/tui/state.rs or src/commands/tui/state.rs)

pub enum Screen {
    SessionList,
    Transcript { session_id: String },
    SubagentTranscript { parent_session_id: String, agent_id: String },
}

pub enum Focus {
    ChatLog,
    SubagentsPanel,
}

pub struct AppState {
    pub screen: Screen,
    // Session list
    pub sessions: Vec<SessionListItem>,   // loaded once
    pub list_selected: usize,
    // Transcript
    pub transcript_entries: Vec<RawEntry>,
    pub transcript_scroll: usize,         // vertical scroll offset
    pub transcript_h_scroll: usize,       // horizontal scroll offset
    pub subagents: Vec<AgentRef>,
    pub subagent_selected: usize,
    pub focus: Focus,
    // Modals
    pub show_quit_dialog: bool,
    pub show_help: bool,
}

Notes

• SessionListItem is a lightweight struct with the display fields (short_id, date, project, model, msg_count, agent_count).
• State transitions: AppState::enter_transcript(session_id) loads entries + subagents. AppState::go_back() pops the screen stack (or just switches back to SessionList).
• Keep all data loading in state transitions so the render function is pure.

Blocked by

• ratatui dependency task (claudbg-78xt)

Summary of Changes\n\nCreated src/tui/mod.rs and src/tui/state.rs with Screen enum, Focus enum, AppState struct, SessionListItem, and AgentRef types. Added state transition methods: new(), enter_transcript(), enter_subagent_transcript(), go_back(). Reuses existing RawEntry and AgentRef types. 11 unit tests all pass. Wired into lib.rs via pub mod tui.