#!/usr/bin/env python3
import sentry_sdk
import os
import requests
import json
import uwsgi
import pickle
from threading import Thread
from queue import Queue

from urllib.parse import urljoin
from config import Config
from pyAudioAnalysis.audioTrainTest import load_model, load_model_knn, classifier_wrapper
from pyAudioAnalysis import audioBasicIO
from pyAudioAnalysis import MidTermFeatures
import numpy

from apscheduler.schedulers.background import BackgroundScheduler

if Config.SENTRY_DSN:
    sentry_sdk.init(
        dsn=Config.SENTRY_DSN,
        send_default_pii=True,
        release=Config.RELEASE_ID,
        environment=Config.RELEASEMODE
    )


def json_datetime_dumper(o):
    if hasattr(o, "isoformat"):
        return o.isoformat()
    else:
        return str(o)


class ModelMemer:

    def __init__(self):
        self._loaded_model = None

    def download_model_if_needed(self):
        models_dir = "/tmp/svm_model"
        os.makedirs(models_dir, exist_ok=True)

        model_file = os.path.join(models_dir, "model")
        means_file = os.path.join(models_dir, "modelMEANS")

        if os.path.isfile(model_file) and self._loaded_model:
            return

        r = requests.get(Config.MODEL_INFO_URL)
        r.raise_for_status()
        self.model_details = r.json()

        r = requests.get(urljoin(Config.MODEL_INFO_URL, self.model_details['files']['model']))
        r.raise_for_status()

        with open(model_file, 'wb') as f:
            f.write(r.content)

        r = requests.get(urljoin(Config.MODEL_INFO_URL, self.model_details['files']['means']))
        r.raise_for_status()

        with open(means_file, 'wb') as f:
            f.write(r.content)

        if self.model_details['type'] == 'knn':
            self.classifier, self.mean, self.std, self.classes, self.mid_window, self.mid_step, self.short_window, \
            self.short_step, self.compute_beat \
                = load_model_knn(model_file)

        else:
            self.classifier, self.mean, self.std, self.classes, self.mid_window, self.mid_step, self.short_window, \
            self.short_step, self.compute_beat \
                = load_model(model_file)

        target_class_name = self.model_details['target_class_name']
        self.target_id = self.classes.index(target_class_name)


def run_classification(audio_file_path: str, memer: ModelMemer):
    memer.download_model_if_needed()

    # run extraction
    sampling_rate, signal = audioBasicIO.read_audio_file(audio_file_path)
    signal = audioBasicIO.stereo_to_mono(signal)

    if sampling_rate == 0:
        raise AssertionError("Could not read the file properly: Sampling rate zero")

    if signal.shape[0] / float(sampling_rate) <= memer.mid_window:
        raise AssertionError("Could not read the file properly: Signal shape is not good")

    # feature extraction:
    mid_features, s, _ = \
        MidTermFeatures.mid_feature_extraction(signal, sampling_rate,
                                               memer.mid_window * sampling_rate,
                                               memer.mid_step * sampling_rate,
                                               round(sampling_rate * memer.short_window),
                                               round(sampling_rate * memer.short_step))

    # long term averaging of mid-term statistics
    mid_features = mid_features.mean(axis=1)
    if memer.compute_beat:
        beat, beat_conf = MidTermFeatures.beat_extraction(s, memer.short_step)
        mid_features = numpy.append(mid_features, beat)
        mid_features = numpy.append(mid_features, beat_conf)

    feature_vector = (mid_features - memer.mean) / memer.std
    class_id, probability = classifier_wrapper(
        memer.classifier, memer.model_details['type'].lower(), feature_vector
    )
    class_id = int(class_id)  # faszom

    return bool((class_id == memer.target_id) and (probability[class_id] > 0.5))


def lapatolas(q: Queue):
    while True:
        message = uwsgi.mule_get_msg()
        q.put(message)


def reporter(q: Queue):
    report = {
        "site": Config.REPORT_ALIAS,
        "measurements": {
            "queue": q.qsize()
        }
    }

    print("Reporting queue length of", report)

    r = requests.post(Config.REPORT_URL, json=report)

    r.raise_for_status()
    if r.status_code != 201:
        print(Config.REPORT_URL, "Wrong response:", r.status_code)


def main():
    memer = ModelMemer()
    requeue = Queue()

    Thread(target=lapatolas, args=(requeue,), daemon=True).start()

    scheduler = None
    if Config.REPORT_URL:
        scheduler = BackgroundScheduler()
        scheduler.add_job(lambda: reporter(requeue), trigger='interval', seconds=Config.REPORT_INTERVAL)
        scheduler.start()

    Thread(target=reporter, args=(requeue,), daemon=True).start()

    while True:
        message = requeue.get(block=True)
        task = pickle.loads(message)
        audio_file_path = task['audio_file_path']
        description = task['description']
        try:
            result = run_classification(audio_file_path, memer)
            if result:
                # upload to real input service
                files = {
                    "file": (
                        os.path.basename(audio_file_path),
                        open(audio_file_path, 'rb').read(),
                        'audio/wave',
                        {'Content-length': os.path.getsize(audio_file_path)}
                    ),
                    "description": (None, json.dumps(description, default=json_datetime_dumper), "application/json")
                }

                r = requests.post(Config.INPUT_SERVICE_URL, files=files)
                r.raise_for_status()
        finally:
            os.remove(audio_file_path)

#    if scheduler:
#        scheduler.stop()


if __name__ == '__main__':
    main()