"""Jellystat API adapter. Credentials and raw history never leave the backend."""

import asyncio
import json
import re
from datetime import datetime

import httpx

from .base import ApiClient


class JellystatError(Exception):
    pass


class HistoryLimitError(JellystatError):
    pass


def same_user_id(left, right) -> bool:
    return bool(left and right) and str(left).replace("-", "").lower() == str(right).replace("-", "").lower()


class JellystatClient(ApiClient):
    PAGE_SIZE = 200
    MAX_PAGES = 50

    def configured(self) -> bool:
        return bool(self.base_url and self.api_key)

    async def _read(self, client: httpx.AsyncClient, method: str, path: str, **kwargs):
        try:
            response = await client.request(method, f"{self.base_url}{path}",
                                            headers={"x-api-token": self.api_key}, **kwargs)
            response.raise_for_status()
            return response.json()
        except (httpx.HTTPError, ValueError) as exc:
            raise JellystatError("Jellystat did not return a valid response") from exc

    async def test_connection(self) -> dict:
        # This protected endpoint confirms API authentication without returning user data.
        async with httpx.AsyncClient(timeout=10.0) as client:
            result = await self._read(client, "GET", "/api/getLibraries")
        if not isinstance(result, list):
            raise JellystatError("Jellystat returned an unexpected library response")
        return {"connected": True}

    async def get_user_history(self, user_id: str, start: datetime, end: datetime) -> tuple[list, list]:
        if not re.fullmatch(r"[A-Za-z0-9_-]{1,128}", user_id):
            raise JellystatError("Invalid linked Jellyfin identity")
        # Only fixed, user-scoped endpoints are used. Never pass browser search/filters through.
        filters = json.dumps([{"field": "ActivityDateInserted", "min": start.isoformat(), "max": end.isoformat()}])
        try:
            async with asyncio.timeout(30):
                async with httpx.AsyncClient(timeout=10.0) as client:
                    libraries = await self._read(client, "GET", "/api/getLibraries")
                    if not isinstance(libraries, list) or any(not isinstance(row, dict) for row in libraries):
                        raise JellystatError("Jellystat returned an unexpected library response")
                    history = []
                    for page in range(1, self.MAX_PAGES + 1):
                        payload = await self._read(client, "POST", "/api/getUserHistory",
                            json={"userid": user_id}, params={"page": page, "size": self.PAGE_SIZE,
                            "sort": "ActivityDateInserted", "desc": "true", "filters": filters})
                        if not isinstance(payload, dict) or not isinstance(payload.get("results"), list):
                            raise JellystatError("Jellystat returned an unexpected history response")
                        rows = payload["results"]
                        try:
                            pages = int(payload["pages"])
                        except (KeyError, TypeError, ValueError) as exc:
                            raise JellystatError("Jellystat did not return history pagination") from exc
                        if pages < 0 or (pages == 0 and rows) or len(rows) > self.PAGE_SIZE:
                            raise JellystatError("Jellystat returned invalid history pagination")
                        if pages > self.MAX_PAGES:
                            raise HistoryLimitError("Select a shorter period to view this history")
                        for row in rows:
                            if not isinstance(row, dict) or not same_user_id(row.get("UserId"), user_id):
                                raise JellystatError("Jellystat returned history for an unexpected account")
                        history.extend(rows)
                        if page >= pages:
                            return history, libraries
                        if not rows:
                            raise JellystatError("Jellystat returned incomplete history")
        except TimeoutError as exc:
            raise JellystatError("Jellystat took too long to return history") from exc
        raise HistoryLimitError("Select a shorter period to view this history")