from flask import request, flash, redirect, url_for
from flask_wtf.csrf import CSRFProtect, validate_csrf, ValidationError
from functools import wraps

csrf = CSRFProtect()


def get_csrf_check_required(redirect_to):
    def wrapper(f):
        @wraps(f)
        def decorated_function(*args, **kwargs):
            if not check_csrf_get():
                flash('CSRF-Check fehlgeschlagen!', 'danger')
                return redirect(url_for(redirect_to))
            return f(*args, **kwargs)
        return decorated_function
    return wrapper


def check_csrf_get():
    try:
        validate_csrf(request.args.get('csrf_token'))
    except ValidationError:
        return False
    return True