MeshTerm/meshterm/ui/admin_picker.py

# SPDX-License-Identifier: Apache-2.0
"""The admin-node picker: choose a remote node you hold (or will enter) credentials for.

Shared by the tools that administer remote nodes over the mesh — TX optimize and the
repeater admin screen — so "pick the node to manage" reads identically everywhere.
Credentialed nodes lead the list in their own 🔑 section (those are the nodes previously
administered, the likeliest picks), repeaters and room servers follow, then everything
else; each section orders by how recently the node was heard. Any contact with a public
key is offerable, since holding a password is a fact about the *user*, not the node.

The pick is a **popup**: a question asked on the way into a tool, drawn as a box and gone
the moment it is answered — never a frame kept under the tool's own page for Esc to land
back on. It used to be held pushed as a hub for the whole visit, so leaving the admin page
landed on the list it was picked from; that read as two places where there is one.
"""

from __future__ import annotations

from typing import TYPE_CHECKING, Any

from rich.text import Text

from ..core.models import NODE_TYPE_REPEATER, NODE_TYPE_ROOM, Contact

if TYPE_CHECKING:
    from ..context import AppContext


def admin_picker_rows(ctx: AppContext, contacts: list[Contact]) -> tuple[list, list[Contact]]:
    """Build the admin-node picker's grouped rows and the contacts they map to.

    Shared so every surface that offers the pick draws the same list: :func:`pick_admin_node`
    runs these rows as a one-shot popup, and TX optimize turns them as the first page of its
    stepped dialog. Rows carry ``value = contact.name``, so a picked name (or a ``default``)
    resolves through ``candidates``.

    Args:
        ctx: Shared application context (for the admin store, which sorts remembered nodes up).
        contacts: The device's known contacts.

    Returns:
        ``(rows, candidates)`` — the grouped select rows and the offerable contacts
        (those holding a key). Both are empty when nothing is offerable; the caller
        notes that and never opens a list at all.
    """
    from .menus import section_heading
    from .theme import name_style
    from .tui import Choice
    from .widgets import DEFAULT_GLYPH, NODE_GLYPHS

    candidates = [c for c in contacts if (c.public_key or c.key_prefix).strip()]
    if not candidates:
        return [], candidates

    def row(contact: Contact) -> Choice:
        # The type mark keeps its own fixed hue; the *name* takes the node's key-derived
        # colour like every other list of nodes (a style on the Text itself would be the
        # row's base and would paint the name the type's colour too).
        glyph, glyph_style = NODE_GLYPHS.get(contact.node_type, DEFAULT_GLYPH)
        label = Text()
        label.append(f"{glyph} ", style=glyph_style)
        label.append(
            contact.name,
            style=name_style(contact.name, contact.public_key or contact.key_prefix),
        )
        return Choice(title=label, value=contact.name)

    def recency(contact: Contact) -> float:
        return -(contact.last_seen.timestamp() if contact.last_seen else 0.0)

    remembered = [c for c in candidates if ctx.admin_store.get(c) is not None]
    infrastructure = [
        c
        for c in candidates
        if c not in remembered and c.node_type in (NODE_TYPE_REPEATER, NODE_TYPE_ROOM)
    ]
    others = [c for c in candidates if c not in remembered and c not in infrastructure]

    items: list = []
    if remembered:
        items.append(section_heading("Remembered admins"))
        items.extend(row(c) for c in sorted(remembered, key=recency))
    if infrastructure:
        items.append(section_heading("Repeaters & rooms"))
        items.extend(row(c) for c in sorted(infrastructure, key=recency))
    if others:
        items.append(section_heading("Other contacts"))
        items.extend(row(c) for c in sorted(others, key=recency))
    return items, candidates


async def pick_admin_node(
    ctx: AppContext,
    contacts: list[Contact],
    *,
    title: str,
    prompt: str,
    default: Contact | None = None,
) -> Contact | None:
    """Pick a remote node to administer, credentialed and infrastructure nodes first.

    A floating popup that comes down as soon as a node is picked. A caller that asks again
    — the login it tried was refused — hands the last pick back as ``default`` so the list
    reopens on it, the way a step of :func:`~meshterm.ui.menus.run_steps` offers its
    previous answer.

    Args:
        ctx: Shared application context (for the UI surface and the admin store).
        contacts: The device's known contacts.
        title: The select screen's heading (names the calling feature).
        prompt: One line above the list saying what the pick is for.
        default: The node to open highlighted on, if any.

    Returns:
        The chosen contact, or ``None`` if cancelled (or there is nothing to pick).
    """
    items, candidates = admin_picker_rows(ctx, contacts)
    if not candidates:
        await _note_nothing_to_pick(ctx, title)
        return None

    choice = await ctx.ui.select(
        title,
        items,
        prompt=prompt,
        default=default.name if default is not None else None,
        floating=True,
    )
    return _resolve(candidates, choice)


async def _note_nothing_to_pick(ctx: AppContext, title: str) -> None:
    """Say there is no offerable node and show it — no list is opened at all."""
    ctx.ui.note("[err]no contacts with a key — receive an advert first[/err]")
    await ctx.ui.present(title=title)


def _resolve(candidates: list[Contact], choice: Any) -> Contact | None:
    """The contact a picked row's name stands for, or ``None`` when nothing was picked."""
    if choice is None:
        return None
    return next((c for c in candidates if c.name == choice), None)