"""Subprocess lifecycle management for the 9Router process."""

import asyncio
import logging
import os
import shutil
import subprocess
import threading

import httpx

from backend.ports import NINE_ROUTER_PORT

import subprocess as _sp

logger = logging.getLogger(__name__)

NINE_ROUTER_URL = f"http://localhost:{NINE_ROUTER_PORT}"
NINE_ROUTER_V1 = f"{NINE_ROUTER_URL}/v1"

_process: subprocess.Popen | None = None

_THIS_DIR = os.path.dirname(os.path.abspath(__file__))


def _forward_output(pipe):
    """Read subprocess output line by line and print with [9router] prefix."""
    try:
        for line in iter(pipe.readline, b''):
            text = line.decode('utf-8', errors='replace').rstrip()
            if text:
                print(f"[9router] {text}", flush=True)
    except Exception:
        pass
    finally:
        try:
            pipe.close()
        except Exception:
            pass


def is_running() -> bool:
    """Check if 9Router is running."""
    try:
        r = httpx.get(f"{NINE_ROUTER_V1}/models", timeout=2.0)
        return r.status_code == 200
    except Exception:
        return False


def _find_9router_dir() -> str | None:
    """Locate the bundled 9Router directory (works in both dev and packaged mode)."""
    _is_packaged = os.environ.get("OPENSWARM_PACKAGED") == "1"

    if _is_packaged:
        # Packaged Electron app — 9router is in extraResources
        # _THIS_DIR is <resources>/backend/apps/nine_router/
        _resources = os.path.dirname(os.path.dirname(os.path.dirname(_THIS_DIR)))
        _candidate = os.path.join(_resources, "9router")
        if os.path.isdir(_candidate):
            return _candidate
    else:
        # Dev mode — 9router is at project root
        _backend_dir = os.path.dirname(os.path.dirname(_THIS_DIR))
        _project_root = os.path.dirname(_backend_dir)
        _candidate = os.path.join(_project_root, "9router")
        if os.path.isdir(_candidate):
            return _candidate

    return None


def _find_node() -> str | None:
    """Find a Node.js binary (works in both dev and packaged mode)."""
    node = shutil.which("node")
    if node:
        return node

    # In packaged Electron app, use the Electron binary with ELECTRON_RUN_AS_NODE=1
    electron_path = os.environ.get("OPENSWARM_ELECTRON_PATH")
    if electron_path and os.path.exists(electron_path):
        return electron_path

    return None


async def ensure_running():
    """Start 9Router if not already running."""
    global _process
    _is_packaged = os.environ.get("OPENSWARM_PACKAGED") == "1"

    if is_running():
        if not _is_packaged:
            try:
                result = _sp.run(
                    ["pgrep", "-f", "next-server"],
                    capture_output=True, text=True, timeout=3,
                )
                if result.stdout.strip():
                    print("9Router: killing stale standalone to use next dev", flush=True)
                    _sp.run(["pkill", "-f", "next-server"], timeout=5)
                    await asyncio.sleep(2)
                else:
                    return
            except Exception:
                return
        else:
            return

    _9router_dir = _find_9router_dir()

    if _is_packaged and _9router_dir:
        standalone_server = os.path.join(_9router_dir, "server.js")
        if not os.path.exists(standalone_server):
            standalone_server = os.path.join(_9router_dir, ".next", "standalone", "server.js")
        if not os.path.exists(standalone_server):
            print("9Router: standalone build not found in", _9router_dir, flush=True)
            return

        node = _find_node()
        if not node:
            print("9Router: Node.js not found, cannot start in packaged mode", flush=True)
            return

        print(f"9Router: starting (production) on port {NINE_ROUTER_PORT}...", flush=True)
        cmd = [node, standalone_server]
        cwd = os.path.dirname(standalone_server)
        env = {
            **os.environ,
            "PORT": str(NINE_ROUTER_PORT),
            "NEXT_PUBLIC_BASE_URL": NINE_ROUTER_URL,
            "NODE_ENV": "production",
        }
        if node == os.environ.get("OPENSWARM_ELECTRON_PATH"):
            env["ELECTRON_RUN_AS_NODE"] = "1"

    elif _9router_dir:
        npx = shutil.which("npx")
        if not npx:
            print("9Router: npx not found, cannot auto-start", flush=True)
            return

        if not os.path.isdir(os.path.join(_9router_dir, "node_modules")):
            print("9Router: installing dependencies...", flush=True)
            npm = shutil.which("npm")
            if npm:
                subprocess.run([npm, "install"], cwd=_9router_dir,
                               stdout=subprocess.DEVNULL, stderr=subprocess.DEVNULL, timeout=120)

        print(f"9Router: starting (dev) on port {NINE_ROUTER_PORT}...", flush=True)
        cmd = [npx, "next", "dev", "--webpack", "-p", str(NINE_ROUTER_PORT)]
        cwd = _9router_dir
        env = {
            **os.environ,
            "PORT": str(NINE_ROUTER_PORT),
            "NEXT_PUBLIC_BASE_URL": NINE_ROUTER_URL,
        }

    else:
        npx = shutil.which("npx")
        if not npx:
            print("9Router: npx not found and no bundled 9router directory", flush=True)
            return
        print(f"9Router: starting (npx) on port {NINE_ROUTER_PORT}...", flush=True)
        cmd = [npx, "9router", "--port", str(NINE_ROUTER_PORT),
               "--no-browser", "--skip-update"]
        cwd = None
        env = {
            **os.environ,
            "PORT": str(NINE_ROUTER_PORT),
            "NEXT_PUBLIC_BASE_URL": NINE_ROUTER_URL,
        }

    try:
        _process = subprocess.Popen(
            cmd,
            cwd=cwd,
            stdin=subprocess.DEVNULL,
            stdout=subprocess.PIPE,
            stderr=subprocess.STDOUT,
            env=env,
        )
        threading.Thread(
            target=_forward_output, args=(_process.stdout,), daemon=True,
        ).start()

        timeout = 20 if _is_packaged else 30
        for _ in range(timeout * 2):
            await asyncio.sleep(0.5)
            if is_running():
                print("9Router: started successfully", flush=True)
                return

        print(f"9Router: did not start within {timeout}s", flush=True)
    except Exception as e:
        print(f"9Router: failed to start: {e}", flush=True)


def stop():
    """Stop the 9Router subprocess."""
    global _process
    if _process:
        try:
            _process.terminate()
            _process.wait(timeout=5)
        except Exception:
            try:
                _process.kill()
            except Exception:
                pass
        _process = None
        logger.info("9Router stopped")