"""Python 3.10+. Standard library only; use on your server."""
import json
import os
import re
from urllib.error import HTTPError
from urllib.request import Request, urlopen

API = "https://api.sendwich.kr"


class SendwichError(Exception):
    def __init__(self, status, code, request_id):
        super().__init__(f"sendwich: {code} ({status})")
        self.status, self.code, self.request_id = status, code, request_id


def _request(path, method="GET", body=None, idempotency_key=None):
    key = os.environ["SENDWICH_API_KEY"]
    headers = {"Authorization": f"Bearer {key}"}
    if body is not None:
        headers["Content-Type"] = "application/json"
    if idempotency_key:
        headers["Idempotency-Key"] = idempotency_key
    data = json.dumps(body).encode("utf-8") if body is not None else None
    try:
        with urlopen(Request(API + path, data=data, headers=headers, method=method), timeout=10) as response:
            return json.load(response)
    except HTTPError as error:
        with error:
            try:
                detail = json.load(error).get("error", {})
            except (ValueError, AttributeError):
                detail = {}
        raise SendwichError(error.code, detail.get("code", "request_failed"),
                            detail.get("request_id") or error.headers.get("X-Request-ID")) from None


def create_verification(body, idempotency_key):
    if not re.fullmatch(r"[A-Za-z0-9_.:-]{8,128}", idempotency_key):
        raise ValueError("Provide a stable Idempotency-Key for this attempt")
    return _request("/v1/verifications", "POST", body, idempotency_key)


def _session_path(verification_id):
    if not re.fullmatch(r"vrf_[A-Za-z0-9_-]+", verification_id):
        raise ValueError("Invalid verification ID")
    return "/v1/verifications/" + verification_id


def get_verification(verification_id):
    return _request(_session_path(verification_id))


def cancel_verification(verification_id):
    return _request(_session_path(verification_id) + "/cancel", "POST")