Terminal: Das prompt, dprompt and dbanner (0.9.1)

- das-shell 0.1.0: the Das two-line bash prompt by default (replaces the
  PS1 of Void's skel .bashrc once), dprompt (Textual prompt builder with
  presets and live preview) and dbanner (SSH login banner editor: canvas
  tools, fields with values, widgets, das-banner service for cached ones,
  Das OS logo and tryzub pictures). Python tests in make test.
- das-server 0.3.0 depends on das-shell; the server installer mentions
  dprompt and dbanner; the desktop image includes it.
- run-qemu.sh forwards the guest's SSH to localhost:2222.
- Hardware fixes: Ventoy menu icon, boot menu titles "Das OS <version>".

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

srcpkgs/das-shell/files/python/das_shell/tui_common.py

@@ -0,0 +1,157 @@
+"""Textual pieces shared by the dprompt and dbanner editors."""
+
+import os
+import subprocess
+import sys
+
+from rich.style import Style
+from rich.text import Text
+from textual import events
+from textual.containers import Horizontal, Vertical
+from textual.message import Message
+from textual.screen import ModalScreen
+from textual.widget import Widget
+from textual.widgets import Button, Input, Label, Select
+
+from . import colors
+from .i18n import t
+
+NONE = "-"  # Select has no None value
+
+
+def color_options(allow_none=True):
+    names = {
+        "black": ("чорний", "black"), "red": ("червоний", "red"), "green": ("зелений", "green"),
+        "yellow": ("жовтий", "yellow"), "blue": ("синій", "blue"), "magenta": ("пурпуровий", "magenta"),
+        "cyan": ("бірюзовий", "cyan"), "white": ("білий", "white"),
+    }
+    opts = [(t("— типовий —", "— default —"), NONE)] if allow_none else []
+    for c in colors.NAMES:
+        base = c[7:] if c.startswith("bright_") else c
+        label = t(*names[base])
+        if c.startswith("bright_"):
+            label = t("яскравий ", "bright ") + label
+        opts.append((Text.assemble(("██ ", c), label), c))
+    return opts
+
+
+def color_value(value):
+    return None if value in (NONE, Select.NULL, None) else value
+
+
+def to_select(color):
+    return color if color in colors.NAMES else NONE
+
+
+class Swatches(Widget):
+    """A row of the 16 colors (and "none") to click; the chosen one is marked."""
+
+    DEFAULT_CSS = """
+    Swatches { height: 2; width: 36; }
+    """
+
+    class Picked(Message):
+        def __init__(self, swatches, color):
+            super().__init__()
+            self.swatches, self.color = swatches, color
+
+    def __init__(self, color=None, allow_none=True, **kw):
+        super().__init__(**kw)
+        self.color, self.allow_none = color, allow_none
+
+    def _items(self):
+        return ([None] if self.allow_none else []) + list(colors.NAMES)
+
+    def render(self):
+        text = Text()
+        for i, c in enumerate(self._items()):
+            if i == 9:
+                text.append("\n")
+            mark = "▣" if c == self.color else "■"
+            if c is None:
+                text.append("∅ " if c != self.color else "▣ ", Style(bold=True))
+            else:
+                text.append(mark * 2 + " " if c == self.color else "██ ", Style(color=c))
+        return text
+
+    def on_click(self, event: events.Click):
+        items = self._items()
+        index = (event.y * 9) + event.x // 3
+        if 0 <= event.x // 3 < 9 and 0 <= index < len(items):
+            self.color = items[index]
+            self.refresh()
+            self.post_message(self.Picked(self, self.color))
+
+
+class AskDialog(ModalScreen):
+    """A few text fields with OK/Cancel; dismisses with {key: value} or None."""
+
+    DEFAULT_CSS = """
+    AskDialog { align: center middle; }
+    AskDialog > Vertical { width: 72; height: auto; border: round $accent; background: $surface; padding: 1 2; }
+    AskDialog Label { margin-top: 1; }
+    AskDialog Horizontal { height: auto; margin-top: 1; align-horizontal: right; }
+    AskDialog Button { margin-left: 2; }
+    """
+    BINDINGS = [("escape", "cancel", t("Скасувати", "Cancel"))]
+
+    def __init__(self, heading, fields):
+        """fields: [(key, label, value or a list of (label, value) choices, current)]"""
+        super().__init__()
+        self.heading, self.fields = heading, fields
+
+    def compose(self):
+        with Vertical():
+            yield Label(Text(self.heading, style="bold"))
+            for key, label, value, *rest in self.fields:
+                yield Label(Text(label))
+                if isinstance(value, list):
+                    yield Select(value, value=rest[0] if rest else value[0][1], allow_blank=False, id="f_" + key)
+                else:
+                    yield Input(str(value), id="f_" + key)
+            with Horizontal():
+                yield Button(t("Скасувати", "Cancel"), id="cancel")
+                yield Button("OK", variant="primary", id="ok")
+
+    def on_mount(self):
+        inputs = self.query(Input)
+        if inputs:
+            inputs.first().focus()
+
+    def _result(self):
+        return {key: self.query_one("#f_" + key).value for key, *_ in self.fields}
+
+    def on_button_pressed(self, event: Button.Pressed):
+        self.dismiss(self._result() if event.button.id == "ok" else None)
+
+    def on_input_submitted(self, event: Input.Submitted):
+        self.dismiss(self._result())
+
+    def action_cancel(self):
+        self.dismiss(None)
+
+
+def run_as_root(app, args):
+    """Runs one of our commands through sudo with the TUI suspended, so sudo can
+    ask for the password. Returns True on success."""
+    exe = "/usr/bin/" + args[0]
+    if os.path.exists(exe):
+        cmd = [exe] + args[1:]
+    else:  # from the source tree
+        module = {"dprompt": "das_shell.cli_prompt", "dbanner": "das_shell.cli_banner"}[args[0]]
+        env = [f"{k}={os.environ[k]}" for k in ("PYTHONPATH", "DAS_SHELL_DATA", "DAS_SHELL_ETC", "DAS_SHELL_CACHE")
+               if k in os.environ]
+        cmd = ["env"] + env + [sys.executable, "-m", module] + args[1:]
+    if os.geteuid() != 0:
+        cmd = ["sudo"] + cmd
+    with app.suspend():
+        print("\n$ " + " ".join(cmd))
+        code = subprocess.run(cmd).returncode
+        if code:
+            input(t("Помилка. Enter — повернутися…", "Failed. Press Enter to go back…"))
+    return code == 0
+
+
+def bar(*buttons):
+    row = Horizontal(*buttons, classes="buttons")
+    return row