#!/usr/bin/env python3
"""Selfprivacy nix channel server."""
import os
import requests

from flask import Flask, request, jsonify, redirect
from flask_restful import Api, Resource, reqparse

# Read the current nixos channel URL from file channel_url.txt
current_channel = open("channel_url.txt", "r").read()

class Channel(Resource):
    def get(self):
        """GET request returns the 301 redirect to the
        current validated NixOS channel 
        """
        return redirect(current_channel, code=301)

    def post(self):
        """POST a new channel, save it to file and update
        current variable"""
        parser = reqparse.RequestParser()
        parser.add_argument('channel', type=str, required=True,
                            help="Channel URL is required")
        args = parser.parse_args()
        channel = args['channel']
        # Save the new channel to file
        with open("channel_url.txt", "w") as f:
            f.write(channel)
        # Update the current channel
        current_channel = channel
        return jsonify({"message": "Channel updated"})

class GetNewChannel(Resource):
    def post(self):
        r = requests.get("https://nixos.org/channels/nixos-21.05")
        channel = r.url
        # Save the new channel to file
        with open("channel_url.txt", "w") as f:
            f.write(channel)
        # Update the current channel
        current_channel = channel
        return jsonify({"message": "Channel updated", "channel": channel})

def create_app():
    app = Flask(__name__)
    api = Api(app)

    app.config['AUTH_KEY'] = os.environ.get('AUTH_KEY') or 'secret!'
    @app.before_request
    def before_request():
        # If request is not GET, check if the auth key is correct
        if request.method != 'GET':
            if request.headers.get('Authorization') != app.config['AUTH_KEY']:
                return jsonify({"message": "Invalid auth key"}), 401

    api.add_resource(Channel, '/nixos-selfpricacy')
    return app

if __name__ == '__main__':
    app = create_app()
    app.run(debug=False)