from __future__ import annotations

import json
import urllib.error
import urllib.parse
import urllib.request

from ..ddns_models import DdnsSettings, UpdateResult
from .base import DnsProviderError


def publish_cloudflare(result: UpdateResult, settings: DdnsSettings) -> None:
    if not settings.cloudflare_api_token or not settings.cloudflare_zone_id:
        raise DnsProviderError("Cloudflare DNS provider is missing required credentials")
    if result.update_ipv4:
        _cloudflare_upsert_record(settings, result.hostname, "A", result.ipv4)
    if result.update_ipv6:
        _cloudflare_upsert_record(settings, result.hostname, "AAAA", result.ipv6)


def delete_cloudflare_records(hostname: str, settings: DdnsSettings) -> None:
    if not settings.cloudflare_api_token or not settings.cloudflare_zone_id:
        raise DnsProviderError("Cloudflare DNS provider is missing required credentials")
    for record_type in ("A", "AAAA"):
        record = _cloudflare_find_record(settings, hostname, record_type)
        if record:
            _cloudflare_request(settings, f"/dns_records/{record['id']}", method="DELETE")


def _cloudflare_upsert_record(settings: DdnsSettings, hostname: str, record_type: str, value: str | None) -> None:
    record = _cloudflare_find_record(settings, hostname, record_type)
    if value is None:
        if record:
            _cloudflare_request(settings, f"/dns_records/{record['id']}", method="DELETE")
        return

    payload = {
        "type": record_type,
        "name": hostname,
        "content": value,
        "ttl": settings.ttl,
        "proxied": False,
    }
    if record:
        _cloudflare_request(settings, f"/dns_records/{record['id']}", method="PATCH", payload=payload)
    else:
        _cloudflare_request(settings, "/dns_records", method="POST", payload=payload)


def _cloudflare_find_record(settings: DdnsSettings, hostname: str, record_type: str) -> dict[str, str] | None:
    query = urllib.parse.urlencode({"type": record_type, "name": hostname})
    response = _cloudflare_request(settings, f"/dns_records?{query}")
    records = response.get("result", [])
    return records[0] if records else None


def _cloudflare_request(
    settings: DdnsSettings,
    path: str,
    method: str = "GET",
    payload: dict[str, object] | None = None,
) -> dict[str, object]:
    url = f"https://api.cloudflare.com/client/v4/zones/{settings.cloudflare_zone_id}{path}"
    body = json.dumps(payload).encode("utf-8") if payload is not None else None
    request = urllib.request.Request(url, data=body, method=method)
    request.add_header("Authorization", f"Bearer {settings.cloudflare_api_token}")
    request.add_header("Content-Type", "application/json")
    try:
        with urllib.request.urlopen(request, timeout=10) as response:
            parsed = json.loads(response.read().decode("utf-8"))
    except urllib.error.HTTPError as exc:
        raise DnsProviderError(f"Cloudflare API returned HTTP {exc.code}") from exc
    except urllib.error.URLError as exc:
        raise DnsProviderError("Cloudflare API request failed") from exc
    except json.JSONDecodeError as exc:
        raise DnsProviderError("Cloudflare API returned invalid JSON") from exc
    if not parsed.get("success", False):
        raise DnsProviderError("Cloudflare API returned an unsuccessful response")
    return parsed