"""Python 3.10+, standard library only. Run on the store server."""
import json
import re
import urllib.error
import urllib.parse
import urllib.request


class _NoRedirect(urllib.request.HTTPRedirectHandler):
    def redirect_request(self, req, fp, code, msg, headers, newurl):
        return None


class DidbanClient:
    def __init__(self, base_url: str, api_key: str):
        u = urllib.parse.urlsplit(base_url)
        if (not u.hostname or u.username or u.password or u.query or u.fragment
                or u.path not in ('', '/') or not (u.scheme == 'https'
                or u.scheme == 'http' and u.hostname in ('127.0.0.1', 'localhost'))):
            raise ValueError('Use an HTTPS origin or localhost.')
        if not re.fullmatch(r'db_(test|live)_[A-Za-z0-9_-]{43}', api_key):
            raise ValueError('Invalid API key.')
        self.base_url = base_url.rstrip('/')
        self.api_key = api_key
        self.opener = urllib.request.build_opener(_NoRedirect())

    def create_invoice(self, request_id: str, amount_rial: str, ttl_minutes: int | None = None, presentation: str = "hosted") -> dict:
        return self._request('/api/v1/invoices', dict(request_id=request_id,
                              amount_rial=amount_rial, ttl_minutes=ttl_minutes, presentation=presentation))

    def get_invoice(self, invoice_id: str) -> dict:
        if not re.fullmatch(r'[0-9a-f-]{36}', invoice_id):
            raise ValueError('Invalid invoice ID.')
        return self._request('/api/v1/invoices/' + invoice_id)

    def get_payment_data(self, invoice_id: str) -> dict:
        if not re.fullmatch(r'[0-9a-f-]{36}', invoice_id):
            raise ValueError('Invalid invoice ID.')
        return self._request('/api/v1/invoices/' + invoice_id + '/payment-data')

    def get_wallet(self) -> dict:
        return self._request('/api/v1/wallet')

    def _request(self, path: str, body: dict | None = None) -> dict:
        request = urllib.request.Request(self.base_url + path,
            data=json.dumps(body, ensure_ascii=False).encode('utf-8') if body is not None else None,
            headers={'Authorization': 'Bearer ' + self.api_key,
                     'Content-Type': 'application/json', 'Accept': 'application/json'})
        try:
            with self.opener.open(request, timeout=20) as response:
                result = json.load(response)
                if not isinstance(result, dict):
                    raise RuntimeError('Invalid API response.')
                return result
        except urllib.error.HTTPError as error:
            raise RuntimeError(f'Didban request failed (HTTP {error.code}).') from None
        except (urllib.error.URLError, TimeoutError):
            raise RuntimeError('Connection failed; retry only with the same request_id.') from None


if __name__ == '__main__':
    import os
    client = DidbanClient(os.environ.get('DIDBAN_API_URL', 'http://127.0.0.1:4321'), os.environ['DIDBAN_API_KEY'])
    invoice = client.create_invoice('PY-ORDER-1001', '550680')
    # Persist invoice['order_id'], invoice['id'] and invoice['amount_rial'] with your local order before showing payment.
    print('Payment URL:', invoice['payment_url'])
    state = client.get_invoice(invoice['id'])
    print('Status:', state['status'], '| Requires review:', state['requires_review'])
    # Only live invoices with a verified bank approval can report paid=true. Never fulfill an order from test_payment.