import logging
from typing import Any, Dict, List, Optional
from urllib.parse import quote

import httpx

from app.core.config import settings

logger = logging.getLogger(__name__)


class VaultwardenServiceError(Exception):
    pass


def _is_configured() -> bool:
    return bool((settings.VAULTWARDEN_BASE_URL or "").strip()) and bool((settings.VAULTWARDEN_API_TOKEN or "").strip())


def _base_url() -> str:
    return (settings.VAULTWARDEN_BASE_URL or "").strip().rstrip("/")


def _headers() -> Dict[str, str]:
    token = (settings.VAULTWARDEN_API_TOKEN or "").strip()
    return {
        "Authorization": f"Bearer {token}",
        "X-API-Token": token,
        "Accept": "application/json",
    }


def _extract_from_cipher(payload: dict) -> Optional[dict]:
    if not isinstance(payload, dict):
        return None

    login = payload.get("login") or payload.get("Login") or {}
    if not isinstance(login, dict):
        login = {}

    username = login.get("username") or login.get("Username")
    password = login.get("password") or login.get("Password")
    totp = login.get("totp") or login.get("Totp")

    uris = login.get("uris") or login.get("Uris") or []
    url = None
    if isinstance(uris, list) and uris:
        first = uris[0] or {}
        if isinstance(first, dict):
            url = first.get("uri") or first.get("Uri")

    if not any([username, password, totp, url, payload.get("notes") or payload.get("Notes")]):
        return None

    return {
        "item_id": str(payload.get("id") or payload.get("Id") or "") or None,
        "item_name": payload.get("name") or payload.get("Name"),
        "username": username,
        "password": password,
        "totp": totp,
        "notes": payload.get("notes") or payload.get("Notes"),
        "url": url,
    }


def _extract_from_custom_payload(payload: Any) -> Optional[dict]:
    if isinstance(payload, dict):
        direct = {
            "item_id": payload.get("item_id") or payload.get("id"),
            "item_name": payload.get("item_name") or payload.get("name"),
            "username": payload.get("username"),
            "password": payload.get("password"),
            "totp": payload.get("totp") or payload.get("otp"),
            "notes": payload.get("notes"),
            "url": payload.get("url"),
        }
        if any(direct.values()):
            return direct

        nested = payload.get("data")
        if isinstance(nested, dict):
            nested_res = _extract_from_custom_payload(nested)
            if nested_res:
                return nested_res

        cipher_res = _extract_from_cipher(payload)
        if cipher_res:
            return cipher_res

    if isinstance(payload, list):
        for item in payload:
            extracted = _extract_from_custom_payload(item)
            if extracted:
                return extracted

    return None


async def _get_json(client: httpx.AsyncClient, url: str) -> Any:
    response = await client.get(url)
    if response.status_code == 404:
        return None
    response.raise_for_status()
    if not response.content:
        return None
    return response.json()


async def resolve_vault_credentials(
    *,
    preferred_item_id: Optional[str],
    fallback_item_ids: List[str],
    search_hint: Optional[str],
) -> dict:
    if not _is_configured():
        return {
            "status": "unavailable",
            "configured": False,
            "message": "Vaultwarden er ikke konfigureret.",
            "checked_item_ids": [],
            "credential": None,
        }

    checked_item_ids: List[str] = []
    item_id_candidates = [preferred_item_id] + list(fallback_item_ids)
    deduped_candidates: List[str] = []
    seen = set()
    for item_id in item_id_candidates:
        candidate = (item_id or "").strip()
        if not candidate or candidate in seen:
            continue
        seen.add(candidate)
        deduped_candidates.append(candidate)

    timeout = httpx.Timeout(connect=6.0, read=10.0, write=10.0, pool=6.0)
    async with httpx.AsyncClient(timeout=timeout, headers=_headers(), follow_redirects=True) as client:
        base = _base_url()

        for item_id in deduped_candidates:
            checked_item_ids.append(item_id)
            try:
                payload = await _get_json(client, f"{base}/api/ciphers/{quote(item_id)}")
                extracted = _extract_from_custom_payload(payload)
                if extracted:
                    return {
                        "status": "ok",
                        "configured": True,
                        "message": "Vault-opslag gennemfoert.",
                        "checked_item_ids": checked_item_ids,
                        "credential": extracted,
                    }
            except httpx.HTTPError as exc:
                logger.warning("Vaultwarden item lookup failed for id=%s: %s", item_id, exc)

        hint = (search_hint or "").strip()
        if hint:
            encoded_hint = quote(hint)
            search_endpoints = [
                f"{base}/api/links/credentials?search={encoded_hint}",
                f"{base}/api/ciphers?search={encoded_hint}",
                f"{base}/api/ciphers?url={encoded_hint}",
            ]

            for endpoint in search_endpoints:
                try:
                    payload = await _get_json(client, endpoint)
                    extracted = _extract_from_custom_payload(payload)
                    if extracted:
                        return {
                            "status": "ok",
                            "configured": True,
                            "message": "Vault-opslag gennemfoert.",
                            "checked_item_ids": checked_item_ids,
                            "credential": extracted,
                        }
                except httpx.HTTPError as exc:
                    logger.info("Vaultwarden search endpoint failed (%s): %s", endpoint, exc)

    return {
        "status": "not_found",
        "configured": True,
        "message": "Ingen vault credentials fundet for linket.",
        "checked_item_ids": checked_item_ids,
        "credential": None,
    }