"""Demo server: python demo/server.py

Accepts WebSocket clients on ws://127.0.0.1:8765, runs the handshake as
responder (identifying each caller by trying its key store against
msg1), prints the verification digest for comparison, then echoes
messages back. Ctrl-C to stop.
"""

import asyncio

from common import key_store, psk, save_store, setup_logging
from websockets import serve
from websockets.exceptions import ConnectionClosed

from quantumpipe import ProtocolError, SecSocket, Verification, sas

log = setup_logging("server")
psk()  # eager: create demo/psk before we listen (avoids a creation race)


async def show_digest(v: Verification) -> None:
    # returning None answers with the app default: proceed unverified --
    # the digest stays exposed (sock.session.verification) for an optional
    # comparison, confirmed later via sock.session.confirm; answering False
    # instead would delete the credential
    log.info("compare these emojis with the client:\n%s", sas.format(v.sas))


async def handle(ws) -> None:
    # per connection: re-read the store; the handshake mutates it in
    # place (rotation, flag, burn, delete) and we persist after
    store = key_store("server")
    sock = SecSocket(ws, store, handlers={Verification: show_digest})
    try:
        await sock.accept()
    except (ProtocolError, ConnectionClosed) as e:
        log.info("handshake failed: %s", e)
        return
    finally:
        save_store("server", store)
    log.info(
        "handshake done (%s, verified=%s), echoing",
        sock.session.state,
        sock.session.verified,
    )
    try:
        while True:
            msg = await sock.receive()
            log.info("received %r", msg)
            await sock.send(f"echo: {msg}")
    except ConnectionClosed:
        log.info("client disconnected")


async def main() -> None:
    async with serve(handle, "127.0.0.1", 8765):
        log.info("listening on ws://127.0.0.1:8765")
        await asyncio.Future()  # serve forever


if __name__ == "__main__":
    try:
        asyncio.run(main())
    except KeyboardInterrupt:
        pass