import time
import pycurl
import itertools
import argparse
import multiprocessing
import paho.mqtt.client
from datetime import datetime
from blist import blist
from dataclasses import dataclass
import threading
import queue


@dataclass(frozen=False, init=True)
class UploadRequest:
    id: int
    upload_started: float = None
    upload_finished: float = None
    upload_status_code: bool = False
    alert_arrived: float = None


@dataclass(frozen=False, init=True)
class ReturnedRequest:
    id: int
    arrived: float


def independent_worker(number_generator, result_queue, filename: str, timeout: float):
    prepared_curl = pycurl.Curl()
    prepared_curl.setopt(pycurl.URL, "https://birb.k8s.kmlabz.com/benchmark")
    prepared_curl.setopt(pycurl.SSL_VERIFYPEER, 0)
    prepared_curl.setopt(pycurl.SSL_VERIFYHOST, 0)
    # prepared_curl.setopt(pycurl.FORBID_REUSE, 0)
    prepared_curl.setopt(pycurl.HTTP_VERSION, pycurl.CURL_HTTP_VERSION_2_0)
    prepared_curl.setopt(pycurl.WRITEFUNCTION, lambda _: None)

    completed_jobs_list = blist()  # O(log n) insert instead of python's O(n)

    worker_stop_time = 0
    worker_completed_job_count = 0

    # Start working!!
    worker_start_time = time.time()
    while True:
        jobid = next(number_generator)
        prepared_curl.setopt(pycurl.HTTPPOST, [
            ('file', (
                pycurl.FORM_FILE, filename  # Copying buffers from Python memory would be even slower... trust me
            )),
            ('description', (
                pycurl.FORM_BUFFERPTR, f'{{"date": "{datetime.now().isoformat()}", "device_id" : "{jobid}"}}',
                pycurl.FORM_CONTENTTYPE, 'application/json',
            ))
        ])

        job_start_time = time.time()
        prepared_curl.perform()
        job_stop_time = time.time()
        status_code = prepared_curl.getinfo(pycurl.HTTP_CODE)

        worker_completed_job_count += 1

        completed_jobs_list.append(UploadRequest(
            id=jobid,
            upload_started=job_start_time,
            upload_finished=job_stop_time,
            upload_status_code=status_code
        ))

        if (job_stop_time - worker_start_time) >= timeout:
            worker_stop_time = job_stop_time
            break

    # end of loop
    runtime = worker_stop_time - worker_start_time
    prepared_curl.close()

    result_queue.put(
        (runtime, worker_completed_job_count, completed_jobs_list)
    )


def mqtt_on_connect(client, userdata, flags, rc):
    client.subscribe(f"command/#")


def mqtt_on_command(client, userdata, message):
    # msg = json.loads(message.payload.decode())
    # if msg['command'] == 'doAlert':
    _id = int(message.topic[8:])  # len('command/') = 8
    userdata.put(ReturnedRequest(id=_id, arrived=time.time()))


def mqtt_on_subscribe(client, userdata, mid, granted_qos):
    userdata.set()


def run_benchmark(num_workers: int, timeout: float, filename: str):
    result_queue = multiprocessing.Queue()

    workers = []
    number_gen = itertools.count()
    for _ in range(num_workers):
        workers.append(multiprocessing.Process(
            target=independent_worker,
            args=(number_gen, result_queue, filename, timeout)
        ))

    for w in workers:
        w.start()

    completed_workers = 0
    all_requests_completed = {}
    while completed_workers < num_workers:
        results = result_queue.get()
        for result in results[2]:
            all_requests_completed[result.id] = result

        completed_workers += 1

    for w in workers:
        w.join()

    return all_requests_completed


def main():
    parser = argparse.ArgumentParser(
        description='Birbnetes Benchmarker 3'
    )

    parser.add_argument('--workers', type=int, required=False, default=1, help='Number of workers (or threads)')
    parser.add_argument('--timeout', type=int, required=False, default=10,
                        help='Maximum time for request sending (0 for unlimited)')

    parser.add_argument('--file', type=str, required=True, help='Name of the sound file to upload')
    parser.add_argument('--target-url', type=str, required=False, default="https://birb.k8s.kmlabz.com/sample",
                        help='The target endpoint')

    parser.add_argument('--inflight-timeout', type=int, required=False, default=30,
                        help='Number of seconds to wait for MQTT messages to arrive after uploading finished (not very precise) (0 for not waiting)')

    parser.add_argument('--mqtt-username', type=str, required=False, default="birbnetes",
                        help="Username for the MQTT server")
    parser.add_argument('--mqtt-port', type=int, required=False, default=1883, help="Port for the MQTT server")
    parser.add_argument('--mqtt-host', type=str, required=False, default="mqtt.kmlabz.com",
                        help="Hostname for the MQTT server")
    parser.add_argument('--mqtt-password', type=str, required=False, default=None, help="Username for the MQTT server")

    args = parser.parse_args()

    print("Workers:", args.workers)
    print("Timeout:", args.timeout, "sec")

    alerts_arrived_queue = queue.Queue()

    print(f"Preparing MQTT (host: {args.mqtt_host}:{args.mqtt_port}, login: {bool(args.mqtt_password)})")
    subscription_waiter = threading.Event()
    # Preparing connection
    mqtt_client = paho.mqtt.client.Client(client_id="10")
    mqtt_client.on_connect = mqtt_on_connect
    mqtt_client.on_subscribe = mqtt_on_subscribe
    mqtt_client.user_data_set(subscription_waiter)
    if args.mqtt_password:
        mqtt_client.username_pw_set(args.mqtt_username, args.mqtt_password)
    # this is a blocking call, will wait until connecion is complete
    mqtt_client.connect(args.mqtt_host, args.mqtt_port, 60)
    # Start loop in background
    mqtt_client.loop_start()
    # Wait for subscription to be made
    subscription_waiter.wait()
    # Set final command reciever
    mqtt_client.user_data_set(alerts_arrived_queue)
    mqtt_client.on_message = mqtt_on_command
    print("MQTT Complete!")

    print("Running benchmark...")
    benchmark_results = run_benchmark(args.workers, args.timeout, args.file)
    print("Waiting for inflight MQTT messages to arrive...")
    # Wait for inflight messages for a little

    total_successful_uploads = len([req for req in benchmark_results.values() if req.upload_status_code == 200])
    all_arrived = False
    for _ in range(int(args.inflight_timeout)):
        time.sleep(1)
        if alerts_arrived_queue.qsize() >= total_successful_uploads:
            all_arrived = True
            break

    if not all_arrived:
        print("WARNING: Not all MQTT Messages arrived!")

    # Disconnectiong MQTT
    mqtt_client.disconnect()
    mqtt_client.loop_stop()  # This stops further recieving MQTT messages

    # Aggregate results
    total_answered = 0
    while True:
        try:
            returned_job = alerts_arrived_queue.get_nowait()
        except queue.Empty:
            break

        try:
            benchmark_results[returned_job.id].alert_arrived = returned_job.arrived
        except KeyError:
            print("Bruh moment: Alert arrived with an id that's not sent", returned_job.id)

        total_answered += 1

    # print some mini statistics
    total_runtime = \
        benchmark_results[max(benchmark_results.keys())].upload_finished - \
        benchmark_results[min(benchmark_results.keys())].upload_started

    print(
        f"{len(benchmark_results)} requests completed: {total_successful_uploads} successfully uploaded and {total_answered} answered"
    )
    print(f"Test total runtime was {total_runtime} seconds")
    print("HTTP Request/sec:", len(benchmark_results) / total_runtime)


if __name__ == '__main__':
    main()