motui

A layered, full-screen TUI toolkit. It takes over the terminal on the alternate screen, renders a document of addressable blocks one diffed row at a time, owns its own scrollback, and keeps pinned bands (fixed top/bottom regions, the frame's footer band) that never scroll away. Any Python program can build its own components and screens on it: the library ships parts, not an application.

Runtime dependency: wcwidth only — Python 3.12+.

Install

pip install motui      # or: uv add motui

The wheel carries its own demo, so python -m motui is one command away.

Quickstart

A minimal interactive app: a Button and a Checkbox (the minimal action primitives), a FocusRing for the keyboard and a Pointer for the mouse. Run it on a real terminal, or drive it with scripted events.

import asyncio

from motui import Button, Checkbox, FocusRing, Key, MouseEvent, Pointer, Text, TUI


async def session(tui):
    ship = Button("Ship")
    tui.add(ship, id="ship")                       # a one-row action
    trace = Checkbox("Trace")
    tui.add(trace, id="trace")                     # a one-row toggle
    ring = FocusRing([ship, trace])                # tab cycles, enter activates
    pointer = Pointer(tui, ring=ring)              # hover + stationary clicks
    while True:
        event = await tui.read_key()
        if event is None or (isinstance(event, Key) and event.name == "c-c"):
            break                                  # EOF, or the quit gesture
        if isinstance(event, MouseEvent):
            if pointer.handle(event):              # the hover moved, or a click landed
                tui.invalidate()
        elif isinstance(event, Key) and event.name == "tab":
            ring.focus_next()                      # the host owns the cycle key
        elif not ring.handle(event):
            ...                                    # the host's own dispatch
        for widget in (ship, trace):
            if widget.chosen is not None:          # read each chosen once
                tui.add(Text(f"{widget.label}: {widget.chosen}"))
                widget.chosen = None
    tui.stop()

asyncio.run(TUI(hover=True).run(session))          # 1003: motion reaches the pointer

The demo

python -m motui runs the library's own front page: a demo that ships in the wheel — eleven pages under a left rail grouped into foundations, components and shell, the page content on the right, the shell built from the same library it shows off. It answers locally: no network, no model.

python -m motui              # a real terminal: the full screen
python -m motui < /dev/null  # piped: replays headless, dumps the final screen
python -m motui --pages      # every page as plain text, no terminal needed

Click a rail label to open that page, or c-n / c-p to step (the ends wrap). tab cycles the page's focus ring, the arrows and enter drive what it focuses, space marks the focused view's cursor row, c-o moves the pane focus, c-f opens the search tier, c-g mounts the dev stats overlay, a drag selects and release copies, q quits. Each page follows one template — a title, one factual line, then its exhibits, each a live component under its own rule with at most one caption line — and the eleven pages — overview, text, layout, actions, forms, views, modals, shell, themes, streaming, notes — carry one exhibit per component family, so every widget in the library is on one of them. The notes page is the manual: how to play, the tour, the signature quick reference and the interaction model.

The API

The root is the curated face — 34 names in one import line. Every other name stays public, one name one home, at its layer namespace:

from motui import TUI, Input, Markdown            # the root: 34 names, one line
from motui.widgets import Row, Panel, Diff        # the component library, complete
from motui.kernel import Style, Line, Selection   # the kernel seam
from motui.keys import DEFAULT_INPUT_KEYMAP
from motui.interaction import FocusRing, Pointer, SelectionGesture, Find, Scrollbar, Toasts

motui.kernel holds the primitives — rows, styles, events, the document model, screen / viewport / painter, the frame model, selection — and imports nothing above itself. motui.keys decodes bytes into events and carries the keymaps; motui.widgets is the component library; motui.interaction is the policy tier a host mounts on the driver; motui.app and motui.testing are the driver and the headless helpers. The full map, deeper seams included, is the table in docs/DESIGN.md.

Everything hangs off the driver and the components it mounts:

tui.add(Button("Ship"), id="ship")     # append a block; address it by id later
tui.remove("ship"); tui.get("ship")    # detach it / fetch it
tui.invalidate()                       # mark the frame dirty; a paint follows
await tui.read_key()                   # the host's loop: keys, pastes, mouse reports
tui.scroll_up(2); tui.reveal("b3", 12) # scroll, or bring an address on screen
tui.split("vertical", ratios=(2, 1))   # tile the focused pane
tui.add_band(Viewport(footer))         # pin a footer band outside every split
tui.hit_test(x, y)                     # a 0-based cell -> the block under it
tui.set_title("my app"); tui.stop()    # OSC 2 title; ask run() to finish

Components render through one frozen protocol — render(width) -> list[Line] — and the interactive ones carry controller verbs beside it: handle(event), click(row, col), move(delta), activate(), select(index), plus the focused and hover flags the tiers write. The library ships Text, Markdown, Delegate, Diff, Input, Editor, ComboBox, Autocomplete, Table, List, Tree, Tabs, NavList, Select, Option, Radio, CheckGroup, Checkbox, Button, Link, Slider, ProgressBar, Spinner, Panel, Notice, Divider, Row, Column, Padding, Spacer, Collapsible, Dialog, Palette, StatusLine and ShortcutBar; the modal layer adds Modal (the controller) beside them.

Features

• alt screen + scrollback — full screen; the whole document stays resident and the page keys scroll the window back through it.
• mouse — the wheel, presses, releases and motion decode into 0-based MouseEvents; tui.hit_test resolves a cell to a block, and the host dispatches.
• selection & copy — SelectionGesture(tui): drag to select in document space, release copies through OSC 52, repeated presses take the word, then the line.
• hover — Pointer(tui): the leaf under the pointer takes its hover flag; a press and release on one cell is a stationary click.
• panes, chrome, overlays — tui.split; Scrollbar; Toasts; Tooltip; the Stats dev readout.
• modal dialogs — Modal(tui, dialog) (or a Palette, or a ComboBox dropdown): a scrimmed panel centered or anchored, the keyboard routed into the body first, a click outside dismissing; confirm_dialog / prompt_dialog are the two builders.
• pinned bands — fixed top/bottom blocks in the frame's own band, outside every split.
• themeable — one frozen Theme; restyle everything with dataclasses.replace, nothing global is mutated.
• markdown + syntax — a streaming-safe rule-registry engine (GFM tables, fenced code, your own rules) with an injectable highlighter.
• keymaps — the text fields' editing keys are tables you can rebind, or unbind to hand the event back.

Building your own shell

The library ships no app shell — no ready-made application, no pinned input box: the components plus the tiers are the whole toolkit, and a host assembles its own. The shape is three pieces: the body document the panes render, a footer Document holding the input and status rows, and tui.add_band(viewport), which parks that footer's viewport in the frame's bottom band — full width, beneath every pane, outside every split, so a pane division never cuts it in half.

import asyncio

from motui import Editor, Key, StatusLine, Text, TUI
from motui.kernel import Document, Viewport
from motui.keys import EDITOR_SUBMIT_KEYMAP


async def session(tui):
    footer = Document()                           # the shell's own footer document
    editor = Editor(keymap=EDITOR_SUBMIT_KEYMAP)  # enter stays the host's submit gesture
    footer.add(editor, id="input")                # the pinned input row
    footer.add(StatusLine(left=("ready",)), id="status")
    tui.add_band(Viewport(footer))                # park the footer under the pane area
    while True:
        key = await tui.read_key()
        if key is None or (isinstance(key, Key) and key.name == "c-c"):
            break                                     # EOF, or the quit gesture
        if isinstance(key, Key) and key.name == "enter":
            tui.add(Text(f"you: {editor.text}"))      # the submit gesture is the host's
            editor.clear()
            continue
        editor.handle(key)                            # every editing key, and a Paste
    tui.stop()

asyncio.run(TUI().run(session))

Every other tier mounts with one more line beside the loop — Pointer, FocusRing, SelectionGesture, Scrollbar, Toasts, Find, Palette — and docs/COMPONENTS.md has the dispatch order they route in plus the build-your-own walkthroughs (a custom chrome rail, a custom overlay, a clickable-through container, a custom Markdown rule).

Styling: Theme

Style is frozen and hashable (fg/bg accept named-16, #rrggbb or (r, g, b) truecolor); Theme is the frozen dataclass that carries every semantic default. Build a variant with dataclasses.replace and hand it to the components you construct — nothing global is mutated:

from dataclasses import replace

from motui import DEFAULT_THEME, Markdown, StatusLine, Style, Text
from motui.kernel import ACCENT

theme = replace(DEFAULT_THEME, accent=Style(fg="#ff8800"), heading=Style(fg="#ff8800"))
Text("hello", theme=theme)            # theme field wins over DEFAULT_THEME
Markdown("# H", theme=theme).render(80)
StatusLine(left=("ready",), theme=theme)  # the two-column row follows the theme
Text("still the default", style=ACCENT)  # an explicit style always wins

Styles resolve once, at construction: explicit style= > the component's theme= field > DEFAULT_THEME. The fields and their defaults are the table in docs/COMPONENTS.md.

Keys and keymaps

KeyDecoder is a pure bytes -> events machine (UTF-8, control names, CSI navigation, bracketed paste, SGR mouse). Editing keys route through a keymap — key event name to the editing method it triggers — which Input/Editor resolve at construction:

from motui import Input
from motui.keys import DEFAULT_INPUT_KEYMAP

field = Input(keymap={**DEFAULT_INPUT_KEYMAP, "c-j": "clear"})
del field.keymap["up"]   # unbound: the host sees the event again

DEFAULT_INPUT_KEYMAP binds the arrows, home/end, backspace/delete, c-a/c-e/c-u, the bounded undo/redo pair and the shift chords for the text-internal selection, but leaves enter unbound — the return key is the host's submit gesture. DEFAULT_EDITOR_KEYMAP adds enter as newline, and EDITOR_SUBMIT_KEYMAP is the editor table with the submit key handed back. The three tables live together in keys/keymap.py; the full semantics are in docs/DESIGN.md.

Docs

• docs/DESIGN.md — how it works and why: the layers and the import table, the coordinate charter, the screen model, the viewport, the painter, the frame model, the driver, selection, keys, and what is deliberately out of scope.
• docs/COMPONENTS.md — how to build with it: the render protocol and the controller verbs, the driver in call order, the component catalogue, the Theme fields, the dispatch order and the build-your-own walkthroughs.
• CHANGELOG.md — what changed between releases.
• docs/releases/ — the release notes as published on GitHub, one page per release.
• CONTRIBUTING.md — how the code is changed and how releases are cut: the gates, the invariants, the versioning policy.

Source: Shingwha/motui — issues and pull requests go to the tracker.

License

MIT — see LICENSE.