"""Diagnostics support for Emby Media Player."""

from __future__ import annotations

import hashlib
from dataclasses import asdict
from typing import Any

from homeassistant.components.diagnostics import async_redact_data
from homeassistant.core import HomeAssistant

from . import EmbyConfigEntry
from .const import CONF_API_KEY

TO_REDACT_ENTRY = {CONF_API_KEY}
# Session-level fields that could allow Emby command injection if leaked
# alongside the API key.
TO_REDACT_SESSION = {"session_id", "device_id", "user_id"}


def _stable_token(value: str) -> str:
    """Stable, irreversible token for a session identifier.

    The first 10 chars of an MD5 are enough to correlate entries in a single
    diagnostics dump without exposing the real Emby ID.
    """
    return "sid-" + hashlib.md5(value.encode("utf-8")).hexdigest()[:10]  # noqa: S324


async def async_get_config_entry_diagnostics(
    hass: HomeAssistant, entry: EmbyConfigEntry
) -> dict[str, Any]:
    """Return diagnostics for a config entry."""
    runtime = entry.runtime_data
    coordinator = runtime.coordinator

    sessions_dump: dict[str, Any] = {}
    if coordinator.data:
        for sid, session in coordinator.data.items():
            session_dict = asdict(session)
            # Convert datetimes to isoformat for JSON friendliness.
            for key, value in list(session_dict.items()):
                if hasattr(value, "isoformat"):
                    session_dict[key] = value.isoformat()
                # Nested play_state.updated_at may also be a datetime.
                if isinstance(value, dict):
                    for sub_k, sub_v in list(value.items()):
                        if hasattr(sub_v, "isoformat"):
                            value[sub_k] = sub_v.isoformat()
            sessions_dump[_stable_token(sid)] = async_redact_data(
                session_dict, TO_REDACT_SESSION
            )

    return {
        "entry": {
            "title": entry.title,
            "data": async_redact_data(dict(entry.data), TO_REDACT_ENTRY),
            "options": dict(entry.options),
            "unique_id": entry.unique_id,
        },
        "server_id": runtime.server_id,
        "websocket_connected": coordinator.websocket_connected,
        "last_update_success": coordinator.last_update_success,
        "sessions": sessions_dump,
    }