#!/usr/bin/env python3
"""Users management module"""
import subprocess
import re
from flask_restful import Resource, reqparse

from selfprivacy_api.utils import WriteUserData, ReadUserData, is_username_forbidden


class Users(Resource):
    """Users management"""

    def get(self):
        """
        Get a list of users
        ---
        tags:
            - Users
        security:
            - bearerAuth: []
        responses:
            200:
                description: A list of users
            401:
                description: Unauthorized
        """
        parser = reqparse.RequestParser(bundle_errors=True)
        parser.add_argument("withMainUser", type=bool, required=False)
        args = parser.parse_args()
        with_main_user = False if args["withMainUser"] is None else args["withMainUser"]

        with ReadUserData() as data:
            users = []
            if with_main_user:
                users.append(data["username"])
            if "users" in data:
                for user in data["users"]:
                    users.append(user["username"])
        return users

    def post(self):
        """
        Create a new user
        ---
        consumes:
            - application/json
        tags:
            - Users
        security:
            - bearerAuth: []
        parameters:
            - in: body
              name: user
              required: true
              description: User to create
              schema:
                type: object
                required:
                    - username
                    - password
                properties:
                    username:
                        type: string
                        description: Unix username. Must be alphanumeric and less than 32 characters
                    password:
                        type: string
                        description: Unix password.
        responses:
            201:
                description: Created user
            400:
                description: Bad request
            401:
                description: Unauthorized
            409:
                description: User already exists
        """
        parser = reqparse.RequestParser(bundle_errors=True)
        parser.add_argument("username", type=str, required=True)
        parser.add_argument("password", type=str, required=True)
        args = parser.parse_args()
        hashing_command = ["mkpasswd", "-m", "sha-512", args["password"]]
        password_hash_process_descriptor = subprocess.Popen(
            hashing_command,
            shell=False,
            stdout=subprocess.PIPE,
            stderr=subprocess.STDOUT,
        )
        hashed_password = password_hash_process_descriptor.communicate()[0]
        hashed_password = hashed_password.decode("ascii")
        hashed_password = hashed_password.rstrip()
        # Check if username is forbidden
        if is_username_forbidden(args["username"]):
            return {"message": "Username is forbidden"}, 409
        # Check is username passes regex
        if not re.match(r"^[a-z_][a-z0-9_]+$", args["username"]):
            return {"error": "username must be alphanumeric"}, 400
        # Check if username less than 32 characters
        if len(args["username"]) >= 32:
            return {"error": "username must be less than 32 characters"}, 400

        with WriteUserData() as data:
            if "users" not in data:
                data["users"] = []

            # Return 409 if user already exists
            if data["username"] == args["username"]:
                return {"error": "User already exists"}, 409

            for user in data["users"]:
                if user["username"] == args["username"]:
                    return {"error": "User already exists"}, 409

            data["users"].append(
                {
                    "username": args["username"],
                    "hashedPassword": hashed_password,
                }
            )

        return {"result": 0, "username": args["username"]}, 201


class User(Resource):
    """Single user managment"""

    def delete(self, username):
        """
        Delete a user
        ---
        tags:
            - Users
        security:
            - bearerAuth: []
        parameters:
            - in: path
              name: username
              required: true
              description: User to delete
              type: string
        responses:
            200:
                description: Deleted user
            400:
                description: Bad request
            401:
                description: Unauthorized
            404:
                description: User not found
        """
        with WriteUserData() as data:
            if username == data["username"]:
                return {"error": "Cannot delete root user"}, 400
            # Return 400 if user does not exist
            for user in data["users"]:
                if user["username"] == username:
                    data["users"].remove(user)
                    break
            else:
                return {"error": "User does not exist"}, 404

        return {"result": 0, "username": username}