from __future__ import annotations

from typing import Any

import aiohttp


def make_session(token: str, timeout: float = 10.0) -> aiohttp.ClientSession:
    """Create a pre-configured ClientSession for use with HAClient."""
    return aiohttp.ClientSession(
        headers={
            "Authorization": f"Bearer {token}",
            "Content-Type": "application/json",
        },
        timeout=aiohttp.ClientTimeout(total=timeout),
    )


class HAClient:
    """Async Home Assistant REST API client.

    Session lifecycle is managed externally — the caller creates the session
    via make_session() at startup and closes it on shutdown.  HAClient is a
    session-borrower: it never opens or closes the session it receives.
    """

    def __init__(self, base_url: str, session: aiohttp.ClientSession) -> None:
        self._base_url = base_url.rstrip("/")
        self._session = session

    async def get_api_status(self) -> dict[str, Any]:
        """GET /api/ — returns {"message": "API running."} when HA is up."""
        async with self._session.get(f"{self._base_url}/api/") as resp:
            resp.raise_for_status()
            return await resp.json()

    async def get_states(self) -> list[dict[str, Any]]:
        """GET /api/states — full entity state list."""
        async with self._session.get(f"{self._base_url}/api/states") as resp:
            resp.raise_for_status()
            return await resp.json()

    async def get_system_health(self) -> dict[str, Any]:
        """GET /api/system_health — per-integration health summary."""
        async with self._session.get(f"{self._base_url}/api/system_health") as resp:
            resp.raise_for_status()
            return await resp.json()

    async def get_config(self) -> dict[str, Any]:
        """GET /api/config — HA configuration including version."""
        async with self._session.get(f"{self._base_url}/api/config") as resp:
            resp.raise_for_status()
            return await resp.json()

    async def get_entity_registry(self) -> list[dict[str, Any]]:
        """GET /api/config/entity_registry — entity registry entries.

        Each entry includes entity_id, platform (integration name), area_id,
        config_entry_id, and other metadata.
        """
        async with self._session.get(
            f"{self._base_url}/api/config/entity_registry"
        ) as resp:
            resp.raise_for_status()
            return await resp.json()

    async def get_automation_traces(self, automation_id: str) -> list[dict[str, Any]]:
        """GET /api/trace/automation/<id> — last run traces for an automation."""
        url = f"{self._base_url}/api/trace/automation/{automation_id}"
        async with self._session.get(url) as resp:
            resp.raise_for_status()
            return await resp.json()

    async def get_error_log(self) -> str:
        """GET /api/error_log — plaintext error log."""
        async with self._session.get(f"{self._base_url}/api/error_log") as resp:
            resp.raise_for_status()
            return await resp.text()