#!/usr/bin/env python3
"""
stop.py — Stop the AI Video Upscaler web application.

Usage:
    python stop.py
"""

import os
import signal
import sys
import time

# ── Paths ────────────────────────────────────────────────────────────────────
BASE_DIR = os.path.dirname(os.path.abspath(__file__))
PID_FILE = os.path.join(BASE_DIR, ".uvicorn.pid")


def _is_running(pid: int) -> bool:
    """Check whether a process with the given PID is still alive and is our server."""
    try:
        os.kill(pid, 0)
    except OSError:
        return False

    # Check /proc/{pid}/cmdline to verify it's our server process
    try:
        cmdline_path = f"/proc/{pid}/cmdline"
        if os.path.exists(cmdline_path):
            with open(cmdline_path, "r") as f:
                cmdline = f.read()
                # Check for indicators of our server
                return "uvicorn" in cmdline or "app.main" in cmdline
    except Exception:
        pass
    # If we can't read cmdline, default to True (safer fallback)
    return True


def stop() -> None:
    if not os.path.isfile(PID_FILE):
        print("ℹ  No server appears to be running (no pidfile found).")
        return

    try:
        pid = int(open(PID_FILE).read().strip())
    except (ValueError, OSError):
        print("⚠  Pidfile exists but is unreadable. Removing it.")
        os.remove(PID_FILE)
        return

    if not _is_running(pid):
        print(f"ℹ  Server (PID {pid}) is not running. Cleaning up pidfile.")
        os.remove(PID_FILE)
        return

    print(f"🛑 Stopping server (PID {pid}) …")

    # Clean up child processes of the server and any lingering upscaler binaries
    import subprocess
    try:
        subprocess.run(["pkill", "-P", str(pid)], capture_output=True)
    except Exception:
        pass
    try:
        subprocess.run(["pkill", "-f", "realesrgan-ncnn-vulkan"], capture_output=True)
        subprocess.run(["pkill", "-f", "rife-ncnn-vulkan"], capture_output=True)
    except Exception:
        pass

    # Graceful shutdown (SIGTERM)
    os.kill(pid, signal.SIGTERM)

    # Wait up to 10 seconds for graceful exit
    for i in range(20):
        time.sleep(0.5)
        if not _is_running(pid):
            break
    else:
        # Force kill if still alive
        print(f"   ⚠  Server didn't stop gracefully, sending SIGKILL …")
        os.kill(pid, signal.SIGKILL)
        time.sleep(0.5)

    # Clean up pidfile
    if os.path.isfile(PID_FILE):
        os.remove(PID_FILE)

    if _is_running(pid):
        print(f"❌ Failed to stop server (PID {pid}).")
        sys.exit(1)
    else:
        print(f"✅ Server stopped.")


if __name__ == "__main__":
    stop()