#!/usr/bin/env python3
"""Disposable loopback-only UI fixture. Never reads legacy configuration.

Usage: python3 scripts/ui_fixture.py target/debug/mirror-tool
Public test-only login: local-ui-fixture-only. Ctrl-C removes fixture state.
"""
import asyncio
import os
from pathlib import Path
import signal
import sys
import tempfile


async def echo(reader, writer):
    try:
        while data := await reader.read(65536):
            writer.write(data)
            await writer.drain()
    except (OSError, asyncio.CancelledError):
        pass
    finally:
        writer.close()
        await writer.wait_closed()


async def main():
    executable = str(Path(sys.argv[1]).resolve())
    with tempfile.TemporaryDirectory(prefix="mirror-ui-") as folder:
        root = Path(folder)
        config = root / "mirror.toml"
        config.write_text('''[web]
listen = "127.0.0.1:16700"
state_file = "state.json"
[network]
drain_timeout_ms = 500
[[teams]]
id = "a"
name = "Loopback A"
address = "127.0.0.1"
[[teams]]
id = "b"
name = "Loopback B"
address = "::1"
[[services]]
id = "echo"
name = "Echo"
listen = "127.0.0.1:18081"
upstream_port = 18082
primary = "a"
replicas = ["b"]
enabled = false
auto_switch = false
replica_policy = "isolate"
''')
        servers = [await asyncio.start_server(echo, address, 18082) for address in ("127.0.0.1", "::1")]
        env = os.environ.copy()
        env["MIRROR_PASSWORD"] = "local-ui-fixture-only"
        process = await asyncio.create_subprocess_exec(executable, "--config", str(config), env=env)
        stop = asyncio.Event()
        for sig in (signal.SIGINT, signal.SIGTERM):
            asyncio.get_running_loop().add_signal_handler(sig, stop.set)
        print("UI fixture: http://127.0.0.1:16700 (loopback only)", flush=True)
        waiter = asyncio.create_task(process.wait())
        stopper = asyncio.create_task(stop.wait())
        await asyncio.wait([waiter, stopper], return_when=asyncio.FIRST_COMPLETED)
        if process.returncode is None:
            process.terminate()
        await process.wait()
        stopper.cancel()
        await asyncio.gather(stopper, return_exceptions=True)
        for server in servers:
            server.close()
            await server.wait_closed()


if __name__ == "__main__":
    asyncio.run(main())