import os
import signal
import subprocess
import sys
import time
from pathlib import Path

import psutil


def kill_flask_servers():
    """
    Kill all Python processes running main.py (Flask servers)
    Uses psutil to find and kill processes more reliably than just using command line
    """
    killed_pids = []

    for proc in psutil.process_iter(["pid", "name", "cmdline"]):
        try:
            cmdline = proc.info["cmdline"]
            if (
                cmdline
                and "python" in proc.info["name"].lower()
                and any(
                    "local_deep_research.web.app" in arg
                    for arg in cmdline
                    if arg
                )
            ):
                pid = proc.info["pid"]
                print(f"Found Flask server process {pid}, killing...")

                # Windows requires SIGTERM
                os.kill(pid, signal.SIGTERM)
                killed_pids.append(pid)

        except (
            psutil.NoSuchProcess,
            psutil.AccessDenied,
            psutil.ZombieProcess,
        ):
            pass

    if killed_pids:
        print(
            f"Killed Flask server processes with PIDs: {', '.join(map(str, killed_pids))}"
        )
    else:
        print("No Flask server processes found.")

    # Give processes time to die
    time.sleep(1)

    # Verify all are dead
    for pid in killed_pids:
        if psutil.pid_exists(pid):
            print(f"Warning: Process {pid} still exists after kill signal.")
        else:
            print(f"Confirmed process {pid} was terminated.")

    return killed_pids


def check_flask_servers():
    """Check if any Flask servers are running and return their PIDs."""
    running_servers = []

    for proc in psutil.process_iter(["pid", "name", "cmdline"]):
        try:
            cmdline = proc.info["cmdline"]
            if (
                cmdline
                and "python" in proc.info["name"].lower()
                and any(
                    "local_deep_research.web.app" in arg
                    for arg in cmdline
                    if arg
                )
            ):
                pid = proc.info["pid"]
                running_servers.append(pid)
        except (
            psutil.NoSuchProcess,
            psutil.AccessDenied,
            psutil.ZombieProcess,
        ):
            pass

    return running_servers


def start_flask_server(port=5000):
    """Start a Flask server in the background."""
    print(f"Starting Flask server on port {port}...")

    # Get the virtual environment Python executable
    # Try multiple common venv locations
    venv_paths = [
        Path("venv_dev") / "bin" / "python",  # Linux/Mac
        Path("venv") / "bin" / "python",  # Linux/Mac
        Path(".venv") / "Scripts" / "python.exe",  # Windows
        Path("venv_dev") / "Scripts" / "python.exe",  # Windows
        Path("venv") / "Scripts" / "python.exe",  # Windows
    ]

    venv_path = None
    for path in venv_paths:
        if path.exists():
            venv_path = str(path)
            break

    if not venv_path:
        print(
            "Error: Could not find Python executable in any common venv location"
        )
        return None

    try:
        # First, check if port is already in use
        import socket

        sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
        result = sock.connect_ex(("127.0.0.1", port))
        sock.close()

        if result == 0:
            print(f"Error: Port {port} is already in use")
            return None

        # Start the Flask server directly without background flags
        # to better catch any startup errors
        process = subprocess.Popen(
            [
                venv_path,
                "-m",
                "local_deep_research.web.app",
                "--port",
                str(port),
            ],
            stdout=subprocess.PIPE,
            stderr=subprocess.PIPE,
            universal_newlines=True,  # Use text mode for easier output reading
        )

        # Wait a moment to ensure the server has time to start
        time.sleep(3)

        # Check if the process is still running
        if process.poll() is None:
            print(f"Flask server started on port {port} with PID {process.pid}")

            # Try to read initial output to see if there are errors
            stdout_data, stderr_data = "", ""
            try:
                # Read with timeout to avoid blocking
                import select

                if os.name == "nt":  # Windows
                    # Windows doesn't support select on pipes, use non-blocking mode
                    import msvcrt

                    if (
                        process.stdout
                        and msvcrt.get_osfhandle(process.stdout.fileno()) != -1
                    ):
                        stdout_data = process.stdout.read(1024) or ""
                    if (
                        process.stderr
                        and msvcrt.get_osfhandle(process.stderr.fileno()) != -1
                    ):
                        stderr_data = process.stderr.read(1024) or ""
                else:  # Unix
                    if (
                        process.stdout
                        and select.select([process.stdout], [], [], 0.5)[0]
                    ):
                        stdout_data = process.stdout.read(1024) or ""
                    if (
                        process.stderr
                        and select.select([process.stderr], [], [], 0.5)[0]
                    ):
                        stderr_data = process.stderr.read(1024) or ""
            except Exception as e:
                print(f"Warning: Could not read process output: {e}")

            # Log any output for debugging
            if stdout_data:
                print(f"Server stdout: {stdout_data.strip()}")
            if stderr_data:
                print(f"Server stderr: {stderr_data.strip()}")

            # Test if the server is actually responding
            try:
                import urllib.request

                with urllib.request.urlopen(
                    f"http://localhost:{port}/", timeout=2
                ) as response:
                    if response.status == 200:
                        print(
                            f"Server is responsive at http://localhost:{port}/"
                        )
                    else:
                        print(
                            f"Warning: Server responded with status {response.status}"
                        )
            except Exception as e:
                print(f"Warning: Could not connect to server: {e}")
                print(
                    "The process is running but the server may not be responding to requests"
                )

            return process.pid
        else:
            stdout, stderr = process.communicate()
            print(
                f"Error starting Flask server. Server process exited with code {process.returncode}"
            )
            if stdout:
                print(f"Server stdout: {stdout.strip()}")
            if stderr:
                print(f"Server stderr: {stderr.strip()}")
            return None

    except Exception as e:
        print(f"Error starting Flask server: {e!s}")
        return None


def start_flask_server_windows(port=5000):
    """Start a Flask server using Windows 'start' command which is more reliable for Windows environments."""
    print(
        f"Starting Flask server on port {port} using Windows 'start' command..."
    )

    # Get the virtual environment Python executable
    # Try multiple common venv locations
    venv_paths = [
        Path("venv_dev") / "Scripts" / "python.exe",  # Windows
        Path("venv") / "Scripts" / "python.exe",  # Windows
        Path(".venv") / "Scripts" / "python.exe",  # Windows
    ]

    venv_path = None
    for path in venv_paths:
        if path.exists():
            venv_path = str(path)
            break

    if not venv_path:
        print(
            "Error: Could not find Python executable in any common venv location"
        )
        return None

    try:
        # Use Windows 'start' command to launch in a new window
        # This is more reliable on Windows for Flask apps
        cmd = f'start "Flask Server" /MIN "{venv_path}" -m local_deep_research.web.app --port {port}'
        subprocess.run(cmd, shell=True, check=True)

        print(f"Flask server starting on port {port}")
        print(
            "Note: The process is running in a minimized window. Close that window to stop the server."
        )

        # Wait a moment to ensure the server has time to start
        time.sleep(3)

        # We can't get the PID easily with this method, but return True to indicate success
        return True

    except Exception as e:
        print(f"Error starting Flask server: {e!s}")
        return None


def restart_server(port=5000):
    """Kill all Flask servers and start a new one."""
    kill_flask_servers()
    print("All Flask server processes terminated.")
    pid = start_flask_server(port)
    if pid:
        print(f"New Flask server started on port {port} with PID {pid}")
        return True
    else:
        print("Failed to start new Flask server")
        return False


def show_status():
    """Show status of running Flask servers."""
    running_servers = check_flask_servers()

    if running_servers:
        print(f"Found {len(running_servers)} running Flask server(s):")
        for pid in running_servers:
            try:
                proc = psutil.Process(pid)
                cmdline = proc.cmdline()
                port = None

                # Try to extract the port number
                for i, arg in enumerate(cmdline):
                    if arg == "--port" and i + 1 < len(cmdline):
                        port = cmdline[i + 1]

                if port:
                    print(f"  - PID {pid}: Running on port {port}")
                else:
                    print(f"  - PID {pid}: Running (port unknown)")

            except (psutil.NoSuchProcess, psutil.AccessDenied):
                print(f"  - PID {pid}: [Process information unavailable]")
    else:
        print("No Flask servers currently running.")

    return len(running_servers) > 0


if __name__ == "__main__":
    if len(sys.argv) > 1:
        if sys.argv[1] == "restart":
            kill_flask_servers()
            print("All Flask server processes terminated.")
            if os.name == "nt":  # Windows
                start_flask_server_windows()
            else:
                start_flask_server()
        elif sys.argv[1] == "start":
            if os.name == "nt":  # Windows
                start_flask_server_windows()
            else:
                start_flask_server()
        elif sys.argv[1] == "status":
            show_status()
        else:
            print(
                "Unknown command. Usage: python kill_servers.py [restart|start|status]"
            )
    else:
        kill_flask_servers()