"""The test application. respond() is shared by the Hypercorn ASGI wrapper (HTTP/1.1, HTTP/2) and the aioquic
HTTP/3 server. It reports which HTTP version the request arrived on, returns N bytes for /bytes/N, and can redirect."""
import os

ALT_SVC = os.environ.get("ALT_SVC_PORT")      # set by serve.py in h3 mode: advertise h3 on that UDP port

def respond(path, version, host, port):
    hdrs = []
    if ALT_SVC:
        hdrs.append((b"alt-svc", ('h3=":%s"; ma=3600' % ALT_SVC).encode()))
    if path.startswith("/bytes/"):
        body = b"x" * int(path.rsplit("/", 1)[1]); ctype = b"application/octet-stream"; status = 200
    elif path == "/redirect":
        hdrs.append((b"location", b"/hello")); return 302, hdrs, b""
    else:
        body = ("hello from %s:%s via HTTP/%s\n" % (host, port, version)).encode(); ctype = b"text/plain"; status = 200
    hdrs += [(b"content-type", ctype), (b"content-length", str(len(body)).encode())]
    return status, hdrs, body

async def app(scope, receive, send):
    if scope["type"] == "lifespan":
        while True:
            m = await receive()
            if m["type"] == "lifespan.startup":
                await send({"type": "lifespan.startup.complete"})
            elif m["type"] == "lifespan.shutdown":
                await send({"type": "lifespan.shutdown.complete"}); return
    if scope["type"] != "http":
        return
    while (await receive()).get("more_body"):   # drain the request body
        pass
    status, headers, body = respond(scope["path"], scope["http_version"], scope["server"][0], scope["server"][1])
    await send({"type": "http.response.start", "status": status, "headers": headers})
    await send({"type": "http.response.body", "body": body})