import os
import argparse
import subprocess
import atexit

from fastapi import FastAPI, Request, HTTPException
from fastapi.middleware.cors import CORSMiddleware
from fastapi.responses import JSONResponse, RedirectResponse

from utils.daily_helpers import create_room as _create_room, get_token

MAX_BOTS_PER_ROOM = 1

# Bot sub-process dict for status reporting and concurrency control
bot_procs = {}


def cleanup():
    # Clean up function, just to be extra safe
    for proc in bot_procs.values():
        proc.terminate()
        proc.wait()


atexit.register(cleanup)


app = FastAPI()

app.add_middleware(
    CORSMiddleware,
    allow_origins=["*"],
    allow_credentials=True,
    allow_methods=["*"],
    allow_headers=["*"],
)


@app.get("/start")
async def start_agent(request: Request):
    print(f"!!! Creating room")
    room_url, room_name = _create_room()
    print(f"!!! Room URL: {room_url}")
    # Ensure the room property is present
    if not room_url:
        raise HTTPException(
            status_code=500,
            detail="Missing 'room' property in request data. Cannot start agent without a target room!")

    # Check if there is already an existing process running in this room
    num_bots_in_room = sum(
        1 for proc in bot_procs.values() if proc[1] == room_url and proc[0].poll() is None)
    if num_bots_in_room >= MAX_BOTS_PER_ROOM:
        raise HTTPException(
            status_code=500, detail=f"Max bot limited reach for room: {room_url}")

    # Get the token for the room
    token = get_token(room_url)

    if not token:
        raise HTTPException(
            status_code=500, detail=f"Failed to get token for room: {room_url}")

    # Spawn a new agent, and join the user session
    # Note: this is mostly for demonstration purposes (refer to 'deployment' in README)
    try:
        proc = subprocess.Popen(
            [
                f"python3 -m bot -u {room_url} -t {token}"
            ],
            shell=True,
            bufsize=1,
            cwd=os.path.dirname(os.path.abspath(__file__))
        )
        bot_procs[proc.pid] = (proc, room_url)
    except Exception as e:
        raise HTTPException(
            status_code=500, detail=f"Failed to start subprocess: {e}")

    return RedirectResponse(room_url)


@app.get("/status/{pid}")
def get_status(pid: int):
    # Look up the subprocess
    proc = bot_procs.get(pid)

    # If the subprocess doesn't exist, return an error
    if not proc:
        raise HTTPException(
            status_code=404, detail=f"Bot with process id: {pid} not found")

    # Check the status of the subprocess
    if proc[0].poll() is None:
        status = "running"
    else:
        status = "finished"

    return JSONResponse({"bot_id": pid, "status": status})


if __name__ == "__main__":
    import uvicorn

    default_host = os.getenv("HOST", "0.0.0.0")
    default_port = int(os.getenv("FAST_API_PORT", "7860"))

    parser = argparse.ArgumentParser(
        description="Daily Storyteller FastAPI server")
    parser.add_argument("--host", type=str,
                        default=default_host, help="Host address")
    parser.add_argument("--port", type=int,
                        default=default_port, help="Port number")
    parser.add_argument("--reload", action="store_true",
                        help="Reload code on change")

    config = parser.parse_args()
    print(f"to join a test room, visit http://localhost:{config.port}/start")
    uvicorn.run(
        "server:app",
        host=config.host,
        port=config.port,
        reload=config.reload,
    )