Struct LiveTerminal 

pub struct LiveTerminal { /* private fields */ }

A continuously-fed terminal emulator with a fixed viewport. Wraps a vt100::Parser and exposes just what the PTY live tap needs.

Implementations

impl LiveTerminal

pub fn new(rows: u16, cols: u16) -> Self

Create a live terminal with a fixed rowsxcols viewport. Dimensions are floored at [MIN_VIEWPORT] (a 0/1-sized grid underflows vt100). Scrollback is left at 0: the snapshot only needs the visible viewport, and the PTY keeps its own raw line_ring for deeper scrollback.

pub fn feed(&mut self, bytes: &[u8])

Feed raw PTY bytes. The parser is persistent, so escape sequences split across chunk boundaries decode correctly.

pub fn osc_title(&self) -> &str

The latest OSC 0/2 title, or "" when none was seen (or the last update was an empty clear).

pub fn osc_progress(&self) -> &str

The latest OSC 9 payload (after 9;), or "" when none was seen. ConEmu progress reads 4;<state>;<percent>.

pub fn clear_osc(&mut self)

Drop retained OSC title/progress evidence. Called when a new command is submitted so a stale title from the previous foreground program can’t leak into the next program’s turn detection.

pub fn in_alt_screen(&self) -> bool

Whether the alternate screen buffer is currently active (vim, htop, and the Ink-based claude/codex TUIs use it).

pub fn resize(&mut self, rows: u16, cols: u16)

Resize the viewport (rows, cols), floored at [MIN_VIEWPORT].

We deliberately do not call vt100’s set_size: its column-shrink reflow underflows / unwraps on perfectly ordinary content (fuzz-found), and since the release build is panic = "abort" such a panic would take the whole MCP server down. Instead we rebuild the parser at the new size and replay the visible text — plain rendered lines can’t retrigger the reflow bug, and TUIs redraw on the SIGWINCH that accompanies a resize.

pub fn snapshot(&self, max_lines: usize) -> Vec<String>

Snapshot the consolidated visible screen as plain-text lines (ANSI already resolved by the emulator), trailing blank lines trimmed. max_lines of 0 returns the whole viewport; otherwise the last N lines.

pub fn cursor_position(&self) -> (u16, u16)

Cursor position as (row, col), 0-based, from the live screen — tells the agent where focus sits in a menu/form it’s piloting.

pub fn snapshot_diff( &mut self, max_lines: usize, threshold: usize, ) -> ScreenUpdate

Diff the current screen against the snapshot the client last saw, update the baseline, and return only what changed. Positional (the terminal is a grid that redraws in place), 1-based rows to match the rest of winx. Returns the full screen on the first look or when more than threshold lines changed (a diff that big isn’t worth the framing).