#This file is part of TALER
#Copyright (C) 2014, 2015, 2016, 2017 GNUnet e.V. and INRIA
#
#TALER is free software; you can redistribute it and/or modify it under the
#terms of the GNU Lesser General Public License as published by the Free Software
#Foundation; either version 2.1, or (at your option) any later version.
#
#TALER is distributed in the hope that it will be useful, but WITHOUT ANY
#WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
#A PARTICULAR PURPOSE.  See the GNU Lesser General Public License for more details.
#
#You should have received a copy of the GNU Lesser General Public License along with
#TALER; see the file COPYING.LGPL.  If not, see <http://www.gnu.org/licenses/>

# @author Marcello Stanisci
# @brief Error generator for responses coming from the exchange

from flask import (request,
                   Flask,
                   jsonify)
import requests
from urllib.parse import (urljoin,
                          urlencode,
                          urlparse,
                          urlunparse)
from pytaler import amount
import base64
import os
import logging
import json
from random import randint
from datetime import datetime

# FIXME

# 1) make this as a standalone executable, like taler-merchant-mitm.
# 2) accept the exchange url as a cli option.

app = Flask(__name__)
app.secret_key = base64.b64encode(os.urandom(64)).decode('utf-8')
logger = logging.getLogger(__name__)
exchange_url = os.environ.get("TALER_EXCHANGE_URL")
assert(None != exchange_url)

# The functions taking 'resp' as parameter are responsible for
# modifying the data to return.

def track_transaction(resp):
    return resp

def track_transfer(resp):
    return resp

@app.route('/', defaults={'path': ''})
@app.route('/<path:path>', methods=["GET", "POST"])
def all(path):
    body = request.get_json()
    url = list(urlparse(request.url))
    xurl = urlparse(exchange_url)
    url[0] = xurl[0]
    url[1] = xurl[1]
    url = urlunparse(url)
    if "POST" == request.method:
        r = requests.post(urljoin(url, path), json=body)
    else:
        r = requests.get(urljoin(url, path), json=body)
    resp = dict()
    if "application/json" == r.headers["Content-Type"]:
        resp = r.json()
    dispatcher = {
        "track_transaction": track_transaction,
        "track_transfer": track_transfer
    }
    func = dispatcher.get(request.headers.get("X-Taler-Mitm"),
                          lambda x: x)
    return jsonify(func(resp)), r.status_code