import json
import logging
import random
import sys
import smpplib.consts
import smpplib.gsm
import smpplib.client
import smpplib.exceptions
import ssl
import select
from threading import Thread

# Load configuration
with open("config.json", "r") as config_file:
    data = json.load(config_file)

smppserverhostname = data["Hostname"]
smppserverport = int(data["Port"])
smppserverusername = data["Username"]
smppserverpassword = data["Password"]
usessl = bool(int(data["SSL"]))
smssendsource = data["Source"]
smssenddest = data["Destination"]
smssendcont = data["Content"]
numberofmsgtosend = int(data['Count'])
validityperiod = data["Validityperiod"]

# Setup logging
logging.basicConfig(level=logging.INFO)


def get_state_description(state):
    state_map = {
        1: "Enroute",
        2: "Delivered",
        3: "Expired",
        4: "Deleted",
        5: "Undeliverable",
        6: "Accepted",
        7: "Unknown",
        8: "Rejected",
    }
    return state_map.get(state, "Unknown")


# Initialize SMPP client with or without SSL
if usessl:
    ssl_context = ssl.create_default_context()
    ssl_context.check_hostname = False
    ssl_context.verify_mode = ssl.CERT_NONE
    ssl_context.options = ssl.OP_NO_SSLv2
    client = smpplib.client.Client(smppserverhostname, smppserverport, allow_unknown_opt_params=True,
                                   ssl_context=ssl_context)
else:
    client = smpplib.client.Client(smppserverhostname, smppserverport, allow_unknown_opt_params=True)

client.set_message_sent_handler(
    lambda pdu: sys.stdout.write('Sent msg with sequence ID {}, got ID back {}\n'.format(pdu.sequence, pdu.message_id)))
client.set_message_received_handler(lambda pdu: sys.stdout.write(
    'DLR received, msg with ID {}, and state {}\n'.format(
        pdu.receipted_message_id,
        get_state_description(pdu.message_state)
    )
))

try:
    print("Connecting to SMPP Server", smppserverhostname, "on port", smppserverport)
    client.connect()
    client.bind_transceiver(system_id=smppserverusername, password=smppserverpassword)
    print("Connected to SMPP Server", smppserverhostname, "on port", smppserverport)
    print("Sending", numberofmsgtosend, "messages towards server", smppserverhostname)
except Exception as e:
    print(f"Error connecting to SMPP Server: {e}")
    client.disconnect()
    sys.exit(1)

try:
    for i in range(numberofmsgtosend):
        parts, encoding_flag, msg_type_flag = smpplib.gsm.make_parts(smssendcont + str(random.randint(1, 10000)))
        for part in parts:
            client.send_message(
                source_addr_ton=smpplib.consts.SMPP_TON_ALNUM,
                source_addr=smssendsource,
                dest_addr_ton=smpplib.consts.SMPP_TON_INTL,
                destination_addr=smssenddest,
                short_message=part,
                data_coding=encoding_flag,
                esm_class=msg_type_flag,
                registered_delivery=True,
            )
    print('Messages sent successfully.')

    def listen_for_delivery_reports():
        print("Waiting for delivery reports...")
        while True:
            try:
                # Get the file descriptor associated with the client's socket
                client_fd = client._socket.fileno()

                # Use select with a timeout to prevent blocking for more than 5 seconds
                ready = select.select([client_fd], [], [], 5)
                if ready[0]:
                    client.listen()
            except smpplib.exceptions.ConnectionError:
                break

    delivery_report_thread = Thread(target=listen_for_delivery_reports)
    delivery_report_thread.start()
    delivery_report_thread.join(timeout=5)
    client.disconnect()

except ConnectionError as e:
    print("Connection error, probably already disconnected.", e)
    # Handle the connection error here, such as retrying the connection or logging the error.

# finally:
#    try:
#        client.disconnect()
#    except ConnectionError as e:
#        print("Connection error, probably already disconnected from SMPP Server", e)
#    print("Disconnected from SMPP server")