import serial
import serial.tools.list_ports
import win32gui
import win32con
import win32com.client
import time
import sys

# --- Config ---
COM_PORT = "COM3"   # change to your Arduino's COM port
BAUD_RATE = 9600
TRIGGER_WORD = "DETECTED"
COOLDOWN_SEC = 1.5  # minimum seconds between switches
IGNORE_TITLES = {"", "Program Manager", "Windows Input Experience"}


def list_ports():
    ports = serial.tools.list_ports.comports()
    if not ports:
        print("No serial ports found.")
    else:
        print("Available ports:")
        for p in ports:
            print(f"  {p.device} — {p.description}")


def get_windows():
    """Return list of (hwnd, title) for all visible, non-minimized top-level windows."""
    results = []

    def callback(hwnd, _):
        if not win32gui.IsWindowVisible(hwnd):
            return
        title = win32gui.GetWindowText(hwnd)
        if title and title not in IGNORE_TITLES:
            results.append((hwnd, title))

    win32gui.EnumWindows(callback, None)
    return results


def force_focus(hwnd):
    """Bring window to foreground, bypassing Windows focus-steal protection."""
    shell = win32com.client.Dispatch("WScript.Shell")
    shell.SendKeys('%')  # simulate Alt — tricks Windows into allowing focus change
    if win32gui.IsIconic(hwnd):
        win32gui.ShowWindow(hwnd, win32con.SW_RESTORE)
    win32gui.SetForegroundWindow(hwnd)


class WindowSwitcher:
    def __init__(self):
        self.index = 0
        self.last_switch = 0

    def switch(self):
        now = time.time()
        if now - self.last_switch < COOLDOWN_SEC:
            return

        windows = get_windows()
        if not windows:
            print("No windows found.")
            return

        self.index = (self.index + 1) % len(windows)
        hwnd, title = windows[self.index]

        try:
            force_focus(hwnd)
            print(f"[{time.strftime('%H:%M:%S')}] → {title}")
            self.last_switch = now
        except Exception as e:
            print(f"Could not switch to '{title}': {e}")


def main():
    if "--list-ports" in sys.argv:
        list_ports()
        return

    if "--test" in sys.argv:
        # Test window switching without Arduino
        print("Test mode — switching window in 2 seconds...")
        time.sleep(2)
        WindowSwitcher().switch()
        return

    print(f"Connecting to {COM_PORT} at {BAUD_RATE} baud...")
    print("Press Ctrl+C to stop.\n")

    switcher = WindowSwitcher()

    try:
        ser = serial.Serial(COM_PORT, BAUD_RATE, timeout=1)
        print(f"Connected. Waiting for '{TRIGGER_WORD}' signal...\n")

        while True:
            line = ser.readline().decode("utf-8", errors="ignore").strip()
            if line == TRIGGER_WORD:
                switcher.switch()

    except serial.SerialException as e:
        print(f"Serial error: {e}")
        print("\nAvailable ports:")
        list_ports()
    except KeyboardInterrupt:
        print("\nStopped.")


if __name__ == "__main__":
    main()