# This file based on: https://github.com/aiortc/aioquic/blob/919ccec9836bf5fa4329b5b050604b09f71d0bdc/examples/http3_client.py

import asyncio
import logging
import time
from collections import deque
from typing import Deque, Dict, Optional
from urllib.parse import urlparse

import aioquic
from aioquic.asyncio.protocol import QuicConnectionProtocol
from aioquic.h3.connection import H3Connection
from aioquic.h3.events import (
    DataReceived,
    H3Event,
    HeadersReceived,
    PushPromiseReceived,
)
from aioquic.quic.events import QuicEvent

logger = logging.getLogger("client")

USER_AGENT = "aioquic/" + aioquic.__version__


class URL:
    def __init__(self, url: str) -> None:
        parsed = urlparse(url)

        self.authority = parsed.netloc
        self.full_path = parsed.path
        if parsed.query:
            self.full_path += "?" + parsed.query
        self.scheme = parsed.scheme


class HttpRequest:
    def __init__(
        self, method: str, url: URL, content: bytes = b"", headers: Dict = {}
    ) -> None:
        self.content = content
        self.headers = headers
        self.method = method
        self.url = url


class HttpClient(QuicConnectionProtocol):
    def __init__(self, *args, **kwargs) -> None:
        super().__init__(*args, **kwargs)

        self.pushes: Dict[int, Deque[H3Event]] = {}
        self._request_events: Dict[int, Deque[H3Event]] = {}
        self._request_waiter: Dict[int, asyncio.Future[Deque[H3Event]]] = {}

        self._http = H3Connection(self._quic)

    async def get(self, url: str, headers: Dict = {}) -> Deque[H3Event]:
        """
        Perform a GET request.
        """
        return await self._request(
            HttpRequest(method="GET", url=URL(url), headers=headers)
        )

    async def post(self, url: str, data: bytes, headers: Dict = {}) -> Deque[H3Event]:
        """
        Perform a POST request.
        """
        return await self._request(
            HttpRequest(method="POST", url=URL(url), content=data, headers=headers)
        )

    def http_event_received(self, event: H3Event) -> None:
        if isinstance(event, (HeadersReceived, DataReceived)):
            stream_id = event.stream_id
            if stream_id in self._request_events:
                # http
                self._request_events[event.stream_id].append(event)
                if event.stream_ended:
                    request_waiter = self._request_waiter.pop(stream_id)
                    request_waiter.set_result(self._request_events.pop(stream_id))

            elif event.push_id in self.pushes:
                # push
                self.pushes[event.push_id].append(event)

        elif isinstance(event, PushPromiseReceived):
            self.pushes[event.push_id] = deque()
            self.pushes[event.push_id].append(event)

    def quic_event_received(self, event: QuicEvent) -> None:
        #  pass event to the HTTP layer
        if self._http is not None:
            for http_event in self._http.handle_event(event):
                self.http_event_received(http_event)

    async def _request(self, request: HttpRequest) -> Deque[H3Event]:
        stream_id = self._quic.get_next_available_stream_id()
        self._http.send_headers(
            stream_id=stream_id,
            headers=[
                (b":method", request.method.encode()),
                (b":scheme", request.url.scheme.encode()),
                (b":authority", request.url.authority.encode()),
                (b":path", request.url.full_path.encode()),
                (b"user-agent", USER_AGENT.encode()),
            ]
            + [(k.lower().encode(), v.encode()) for (k, v) in request.headers.items()],
        )
        self._http.send_data(stream_id=stream_id, data=request.content, end_stream=True)

        waiter = self._loop.create_future()
        self._request_events[stream_id] = deque()
        self._request_waiter[stream_id] = waiter
        self.transmit()

        return await asyncio.shield(waiter)


async def perform_http_request(
    client: HttpClient,
    url: str,
    headers: Optional[dict]
) -> Dict[int, Deque[H3Event]] :
    # perform request
    start = time.time()
    if headers:
        http_events = await client.get(url, headers=headers)
    else:
        http_events = await client.get(url)
    method = "GET"
    elapsed = time.time() - start

    # print speed
    octets = 0
    for http_event in http_events:
        if isinstance(http_event, DataReceived):
            octets += len(http_event.data)
    logger.info(
        "Response received for %s %s : %d bytes in %.1f s (%.3f Mbps)"
        % (method, urlparse(url).path, octets, elapsed, octets * 8 / elapsed / 1000000)
    )

    return http_events


def prepare_response(
    http_events: Deque[H3Event]
) -> str:

    byteslist = []
    headers = {}

    for http_event in http_events:
        if isinstance(http_event, HeadersReceived):
            headers.update(http_event.headers)
        elif isinstance(http_event, DataReceived):
            byteslist.append(http_event.data)

    return headers, b''.join(byteslist)