import os
import json
import time
import threading

CHAT_FILE = "global_chat.json"

class ChatNetwork:
    def __init__(self, ui_callback):
        self.ui_callback = ui_callback
        self.my_pid = os.getpid()
        self.is_running = True
        self.last_read_index = 0 

        if not os.path.exists(CHAT_FILE):
            with open(CHAT_FILE, 'w') as f:
                json.dump([], f)

    def start_server(self):
        """Inicia el hilo que lee el chat constantemente."""
        threading.Thread(target=self._monitor_chat, daemon=True).start()

    def _monitor_chat(self):
        """Lee el archivo global y muestra solo los mensajes nuevos."""
        while self.is_running:
            try:
                if os.path.exists(CHAT_FILE):
                    with open(CHAT_FILE, 'r') as f:
                        messages = json.load(f)
                        
                        if len(messages) > self.last_read_index:
                            new_msgs = messages[self.last_read_index:]
                            
                            for msg in new_msgs:
                                mi_prefijo = f"PID {self.my_pid}:"
                                
                                if msg.startswith(mi_prefijo):
                                    mensaje_visual = msg.replace(mi_prefijo, "Yo:")
                                else:
                                    mensaje_visual = msg
                                    
                                self.ui_callback(mensaje_visual)
                            
                            self.last_read_index = len(messages)
            except Exception:
                pass 
            time.sleep(0.5)

    def send_message(self, message):
        """Añade un mensaje al archivo global."""
        try:
            if os.path.exists(CHAT_FILE):
                with open(CHAT_FILE, 'r') as f:
                    data = json.load(f)
            else:
                data = []
            
            data.append(f"PID {self.my_pid}: {message}")
            
            with open(CHAT_FILE, 'w') as f:
                json.dump(data, f)
            return True
        except Exception:
            return False

    def stop(self):
        self.is_running = False