from crypt_random import secure_random
from lora_handler import LoRaHandler, LoRaMessage

import time
import uasyncio as asyncio
import json

from machine import Pin
led = Pin("LED", Pin.OUT)


class Connection:
    def __init__(self, bluetooth_handler=None):
        # ensure led is off during initialization to indicate we're not ready yet
        led.value(0)
        
        try:
            with open("settings.json", "r") as f:
                self.settings = json.load(f)
        except FileNotFoundError:
            print("No settings file found. Using defaults...")
            self.settings = {
                "display_name": "Unnamed Node"
            }
        
        self.bluetooth_handler = bluetooth_handler
        self.load_public_constants()
        
        # generate diffie-hellman keys
        print("Generating keys...")
        print("    - Generating private key...")
        self.private_key = int.from_bytes(secure_random(32), "big") # 32 bytes = 256 bits
        print("    - Generating public key...")
        self.public_key = pow(self.G, self.private_key, self.P)
        
        # start lora handler
        self.lora = LoRaHandler()
        
        # turn on status LED to indicate we're ready
        led.value(1)
        
    async def bluetooth_listener(self):
        while True:
            msg_type, payload = await self.bluetooth_handler.packets.get()
            
            if msg_type == 3: # advertise self
                self.lora.advertise()
                
    def bluetooth_send(self, msg_type: int, payload: dict):
        if self.bluetooth_handler:
            self.bluetooth_handler.send_packet(msg_type, payload)
        
    async def start(self):
        print("Starting connection...")
        
        if self.bluetooth_handler:
            asyncio.create_task(self.bluetooth_listener())
        
        while True:
            msg: LoRaMessage = await self.lora.message_queue.get()
            print(f"Received message from {msg.sender_id}: {msg.payload}")
            
            if msg.payload == b"Ping!":
                self.bluetooth_send(4, {"id": msg.sender_id, "name": self.settings["display_name"]})
            
        
    def load_public_constants(self):
        with open("public_constants.txt", "r") as f:
            self.P = int(f.readline(), 16)
            self.G = int(f.readline(), 16)