"""Helpers for building per-display DeviceInfo.

Each physical monitor is exposed as its own HA device (linked back to the
media-server hub via `via_device`) so that per-display entities (power
switch, brightness, future per-display sensors) cluster together, can be
placed in their own area/room, and participate in device-based automations.
"""

from __future__ import annotations

from typing import Any

from homeassistant.config_entries import ConfigEntry
from homeassistant.helpers.entity import DeviceInfo

from .const import DOMAIN


def display_label(monitor: dict[str, Any]) -> str:
    """Return a user-friendly label for a display monitor.

    Resolution is appended when available so that two monitors sharing a
    name (e.g. two "Generic PnP Monitor" entries) remain distinguishable.
    """
    name = monitor.get("name") or f"Monitor {monitor['id']}"
    resolution = monitor.get("resolution")
    if resolution:
        return f"{name} ({resolution})"
    return name


def display_device_identifier(entry: ConfigEntry, monitor_id: int) -> tuple[str, str]:
    """Return the stable identifier tuple for a per-display device."""
    return (DOMAIN, f"{entry.entry_id}_display_{monitor_id}")


def display_device_info(entry: ConfigEntry, monitor: dict[str, Any]) -> DeviceInfo:
    """Build DeviceInfo for a per-display device linked to the hub.

    Prefers the manufacturer/model reported by the monitor's EDID; falls back
    to integration-level defaults so devices still appear sensibly even when
    EDID parsing returns blanks.
    """
    manufacturer = (monitor.get("manufacturer") or "").strip() or "Remote Media Player"
    model = (monitor.get("model") or "").strip() or "Display"

    return DeviceInfo(
        identifiers={display_device_identifier(entry, monitor["id"])},
        via_device=(DOMAIN, entry.entry_id),
        # HA's device tree already shows the parent hub above its children
        # via `via_device`, so re-stating the entry title here would just
        # duplicate the hub name on every child row.
        name=display_label(monitor),
        manufacturer=manufacturer,
        model=model,
    )