from __future__ import annotations

import argparse
import sys

from .ingress import BrainEventIngress
from .runtime import DemoEngine
from .server import parse_bind, serve
from .source import StreamSource, SyntheticSource, read_stream_url, require_opencv


def build_parser() -> argparse.ArgumentParser:
    parser = argparse.ArgumentParser(description="YoVision Brain single-stream engineering prototype")
    parser.add_argument("--source", choices=("synthetic", "stream"), default="synthetic")
    parser.add_argument("--stream-url-file", help="absolute external file containing one RTSP URL")
    parser.add_argument("--bind", default="127.0.0.1:8090", help="loopback bind address")
    parser.add_argument("--fps", type=float, default=2.0, help="prototype processing FPS (0, 30]")
    parser.add_argument("--event-ingress-config", help="absolute external Brain-to-Bell ingress configuration")
    return parser


def main(argv: list[str] | None = None) -> int:
    args = build_parser().parse_args(argv)
    try:
        require_opencv()
        parse_bind(args.bind)
        if args.source == "stream":
            if not args.stream_url_file:
                raise ValueError("--stream-url-file is required for stream mode")
            source = StreamSource(read_stream_url(args.stream_url_file))
        else:
            if args.stream_url_file:
                raise ValueError("--stream-url-file is only valid for stream mode")
            source = SyntheticSource()
        event_ingress = BrainEventIngress.from_file(args.event_ingress_config) if args.event_ingress_config else None
        engine = DemoEngine(source, fps=args.fps, event_ingress=event_ingress)
    except (RuntimeError, ValueError) as exc:
        print(f"Brain demo configuration error: {exc}", file=sys.stderr)
        return 2
    print(f"Brain demo listening on http://{args.bind}/brain-demo")
    print("Engineering prototype only; synthetic replay and HOG output are not production model evidence.")
    try:
        serve(engine, args.bind)
    except KeyboardInterrupt:
        return 0
    return 0


if __name__ == "__main__":
    raise SystemExit(main())