import numpy as np
import matplotlib.pyplot as plt
from watchdog.observers import Observer
from watchdog.events import FileSystemEventHandler
import time
import os

needs_update = True  # flag global

def plot_constellations(ref_file, rx_file, title="Constellation Comparison", save_path=None):
    ref_data = np.atleast_2d(np.loadtxt(ref_file))
    rx_data = np.atleast_2d(np.loadtxt(rx_file))
    
    x_ref, y_ref = ref_data[:,0], ref_data[:,1]
    x_rx, y_rx = rx_data[:,0], rx_data[:,1]

    plt.clf()  # efface la figure précédente
    plt.scatter(x_ref, y_ref, color='dodgerblue', s=80, marker='o', edgecolors='k', label='Référence')
    plt.scatter(x_rx, y_rx, color='tomato', s=80, marker='x', alpha=0.6, label='Reçu')

    all_x = np.concatenate([x_ref, x_rx])
    all_y = np.concatenate([y_ref, y_rx])
    margin = 0.15 * max(np.ptp(all_x), np.ptp(all_y))
    plt.xlim(min(all_x)-margin, max(all_x)+margin)
    plt.ylim(min(all_y)-margin, max(all_y)+margin)

    plt.grid(True, which='both', linestyle='--', linewidth=0.5, alpha=0.7)
    plt.axhline(0, color='black', linewidth=1)
    plt.axvline(0, color='black', linewidth=1)
    plt.xlabel('In-phase (I)', fontsize=12)
    plt.ylabel('Quadrature (Q)', fontsize=12)
    plt.title(title, fontsize=14, fontweight='bold')
    plt.gca().set_aspect('equal', adjustable='box')
    plt.legend()
    if save_path:
        plt.savefig(save_path, dpi=300, bbox_inches='tight')
    plt.pause(0.1)

class FileChangeHandler(FileSystemEventHandler):
    def on_modified(self, event):
        global needs_update
        if event.src_path.endswith("constellation_ref.dat") or event.src_path.endswith("constellation.dat"):
            print(f"{event.src_path} modifié")
            needs_update = True  # on ne fait que signaler

if __name__ == "__main__":
    ref_file = "constellation_ref.dat"
    rx_file = "constellation.dat"

    plt.ion()
    plt.figure(figsize=(7,7))
    plot_constellations(ref_file, rx_file)

    event_handler = FileChangeHandler()
    observer = Observer()
    observer.schedule(event_handler, path=os.path.dirname(os.path.abspath(ref_file)) or '.', recursive=False)
    observer.start()

    try:
        while True:
            if needs_update:
                plot_constellations(ref_file, rx_file)
                needs_update = False
            time.sleep(0.2)  # boucle principale
    except KeyboardInterrupt:
        observer.stop()
    observer.join()