def save_figure_to_bytes():
    buf = io.BytesIO()
    plt.savefig(buf, format="png")
    plt.close()
    encoded_str = str(base64.b64encode(buf.getvalue()), "UTF-8")
    buf.close()
    return encoded_str

import base64
import urllib
import numpy as np
import parselmouth as parselmouth
from flask import Flask, make_response
import tempfile
from flask import request
import matplotlib.pyplot as plt
from urllib.parse import unquote
import io
import os
from memory_profiler import profile

application = Flask(__name__)


@profile(precision=4)
def get_data_and_write_temp_file():
    plt.close()
    # strip off url encoding
    file_data = urllib.parse.unquote(request.data).replace("file_data=", "")
    # strip off base64
    file_data_no_base64 = base64.standard_b64decode(file_data)
    with tempfile.TemporaryDirectory() as td:
        f_name = os.path.join(td, 'test')
        with open(f_name, 'wb') as fh:
            fh.write(file_data_no_base64)
            fh.seek(0)
            value_to_return = parselmouth.Sound(f_name)  
            fh.close()
        return value_to_return


@profile(precision=4)
def save_figure_to_bytes():
    plt.savefig(buf, format="png")
    plt.close()
    encoded_str = str(base64.b64encode(buf.getvalue()), "UTF-8")
    buf.close()
    return encoded_str


@profile(precision=4)
@application.route('/get_amplitude', methods=['POST', 'GET'])
def get_amplitude():
    snd = get_data_and_write_temp_file()
    # do the figure actions to create plot.
    plt.figure()
    plt.plot(snd.xs(), snd.values.T)
    plt.xlim([snd.xmin, snd.xmax])
    plt.xlabel("time [s]")
    plt.ylabel("amplitude")

    encoded_str = save_figure_to_bytes()
    return encoded_str


if __name__ == '__main__':
    application.run(host="0.0.0.1")