from LoRaPy.lorapy import LoRaPy
import keys
import time


def receive_callback(payload):
    print(payload)

"""
LoRaPy takes
    :param dev_addr: list. The "Device address" from your device, given by thethings.network.
    :param nw_key: list. The "NwkSKey" from your device, given by thethings.network.
    :param app_key: list. The "AppSKey" from your device, given by thethings.network.
    :param verbose: bool. True if verbose informations should be printed to the console.
    :param callback: function. Callback-function to handle downlinks out of the the things stack.
""" 
lora = LoRaPy(keys.devaddr, keys.nwskey, keys.appskey, True, receive_callback)

while True:
    """
    lora.send(message: string, spreading_factor: integer)
    """
    lora.send('this is your payload-string', 7)
    time.sleep(900)

from LoRaPy.lorapy import LoRaPy
import keys
import time
last_send = 0


def receive_callback(payload):
    global last_send
    print(payload)
    # reset time 
    last_send = time.time()

    
def try_to_send(message):
    # wait at least 900s before sending next message.
    if last_send + 900 > time.time():
        return
    
    # more than 900s since the last sending.
    lora.send(message, 7)


lora = LoRaPy(keys.devaddr, keys.nwskey, keys.appskey, True, receive_callback)

while True:
    time.sleep(30)
    try_to_send('this is your payload-string')