# Copyright (c) 2020 Andika Wasisto
#
# Permission is hereby granted, free of charge, to any person obtaining a copy
# of this software and associated documentation files (the "Software"), to deal
# in the Software without restriction, including without limitation the rights
# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
# copies of the Software, and to permit persons to whom the Software is
# furnished to do so, subject to the following conditions:
#
# The above copyright notice and this permission notice shall be included in all
# copies or substantial portions of the Software.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
# SOFTWARE.

import threading

from flask import Flask, request, Response
from flask_sockets import Sockets
from gevent import pywsgi
from geventwebsocket.handler import WebSocketHandler

from quanttp.data.qng_wrapper import QngWrapper
from quanttp.data.qng_wrapper_mock import QngWrapperMock


app = Flask(__name__)
sockets = Sockets(app)

qng_wrapper = QngWrapper()
# qng_wrapper = QngWrapperMock()


@app.route('/api/randint32')
def api_randint32():
    qng_wrapper.clear()
    return Response(str(qng_wrapper.randint32()), content_type='text/plain')


@app.route('/api/randuniform')
def api_randuniform():
    qng_wrapper.clear()
    return Response(str(qng_wrapper.randuniform()), content_type='text/plain')


@app.route('/api/randnormal')
def api_randnormal():
    qng_wrapper.clear()
    return Response(str(qng_wrapper.randnormal()), content_type='text/plain')


@app.route('/api/randbytes')
def api_randbytes():
    try:
        length = int(request.args.get('length'))
        if length < 1:
            return Response('length must be greater than 0', status=400, content_type='text/plain')
        elif length > 8192:
            return Response('length must be less than or equal to 8192', status=400, content_type='text/plain')
        qng_wrapper.clear()
        return Response(qng_wrapper.randbytes(length), content_type='application/octet-stream')
    except ValueError as e:
        return Response(str(e), status=400, content_type='text/plain')


@sockets.route('/ws')
def ws(websocket):
    subscribed = [False]
    while not websocket.closed:
        threading.Thread(target=handle_ws_message, args=(websocket.receive(), websocket, subscribed)).start()


def handle_ws_message(message, websocket, subscribed):
    try:
        split_message = message.strip().upper().split()
        if split_message[0] == 'RANDINT32':
            qng_wrapper.clear()
            websocket.send(str(qng_wrapper.randint32()))
        elif split_message[0] == 'RANDUNIFORM':
            qng_wrapper.clear()
            websocket.send(str(qng_wrapper.randuniform()))
        elif split_message[0] == 'RANDNORMAL':
            qng_wrapper.clear()
            websocket.send(str(qng_wrapper.randnormal()))
        elif split_message[0] == 'RANDBYTES':
            length = int(split_message[1])
            if not 1 <= length <= 8192:
                raise ValueError()
            qng_wrapper.clear()
            websocket.send(qng_wrapper.randbytes(length))
        elif split_message[0] == 'SUBSCRIBEINT32':
            if not subscribed[0]:
                subscribed[0] = True
                qng_wrapper.clear()
                while subscribed[0] and not websocket.closed:
                    websocket.send(str(qng_wrapper.randint32()))
        elif split_message[0] == 'SUBSCRIBEUNIFORM':
            if not subscribed[0]:
                subscribed[0] = True
                qng_wrapper.clear()
                while subscribed[0] and not websocket.closed:
                    websocket.send(str(qng_wrapper.randuniform()))
        elif split_message[0] == 'SUBSCRIBENORMAL':
            if not subscribed[0]:
                subscribed[0] = True
                qng_wrapper.clear()
                while subscribed[0] and not websocket.closed:
                    websocket.send(str(qng_wrapper.randnormal()))
        elif split_message[0] == 'SUBSCRIBEBYTES':
            chunk = int(split_message[1])
            if not 1 <= chunk <= 8192:
                raise ValueError()
            qng_wrapper.clear()
            if not subscribed[0]:
                subscribed[0] = True
                while subscribed[0] and not websocket.closed:
                    websocket.send(qng_wrapper.randbytes(chunk))
        elif split_message[0] == 'UNSUBSCRIBE':
            subscribed[0] = False
            websocket.send('UNSUBSCRIBED')
    except (ValueError, BlockingIOError):
        pass
    except Exception as e:
        websocket.close(code=1011, message=str(e))


@app.errorhandler(Exception)
def handle_exception(e):
    return Response(e.description, status=e.code, content_type='text/plain')


server = pywsgi.WSGIServer(('0.0.0.0', 62456), application=app, handler_class=WebSocketHandler)
server.serve_forever()