#!/usr/bin/env python3

import os
import sys
import argparse
import pathlib
import requests
import json
import urllib.parse


def call_katello_api(Outfile=None):
    try:
        requests.packages.urllib3.disable_warnings(requests.packages.urllib3.exceptions.InsecureRequestWarning)
        resp = requests.get('https://katello.example.com/api/subnets', verify=False, auth=(args.user, args.passwd))
        if not resp.ok:
            if resp.status_code >= 400:
                print(resp.text)
            return False
    except requests.exceptions.RequestException as e:
        print(e)
        sys.exit(1)
    
    subnets = resp.json()['results']  # the 'results' key is a list (Python list) of subnets
    for subnet in subnets:
        # multiple subnets can have same VLAN, e.g. there's 3740 for both Data Network (QTS) and Data Network (ELK)
        if subnet['vlanid'] == int(args.vlanid):
            try:
                # curl -s -k -u "user:pass" -X GET 'https://katello.example.com/api/v2/hosts?search=subnet.name%3D%22Data+Network+%28QTS%29%22'
                url = '%s/%s?%s' % ('https://katello.example.com/api/v2', 'hosts', 'search=subnet.name' + urllib.parse.quote_plus('="' + subnet['name'] + '"') + '&per_page=500')
                print('\n%s, calling API endpoint: %s' % (subnet['name'], url))
                resp = requests.get(url, verify=False, auth=(args.user, args.passwd))
                if not resp.ok:
                    return False
                hosts = resp.json()['results']
                for host in hosts:
                    # vlan,ip,hostname,location,os,vm,desc,dept
                    record = "%s,%s,%s,%s,%s,%s,%s,%s\n" % (args.vlanid,host['ip'],host['name'],host['location_name'],host['operatingsystem_name'],host['model_name'],host['hostgroup_name'].capitalize() if host['hostgroup_name'] is not None else 'N/A','GasOps')
                    print(record)
                    if Outfile is not None:
                        Outfile.write(record)
            except requests.exceptions.RequestException as e:
                print(e)
                sys.exit(1)
    return True


if __name__ == "__main__":
    parser = argparse.ArgumentParser(description="Gets inventory of hosts using Katello API based on given VLAN ID and writes it to a CSV file", parents=())
    parser.add_argument("-u", "--user", dest='user', help="katello user", required=True)
    parser.add_argument("-p", "--passwd", dest='passwd', help="katello password", required=True)
    parser.add_argument("-v", "--vlan", dest='vlanid', help="vlan id of the subnet", required=True)
    parser.add_argument("-o", "--output", dest='path', default="stdout", help="optional path where to write a CSV file containing inventory of hosts")
    args = parser.parse_args()

    outfile = None
    if args.path != "stdout":
        outpath = pathlib.Path(args.path).resolve()
        outfile = open(os.path.join(outpath, 'vlan-' + args.vlanid + '-host-inventory.csv'), 'w')
        outfile.write('VLAN,IP,Network Name,Location,Operating System,Virtual or Physical,Description,Department\n')

    success = call_katello_api(Outfile=outfile)
    if not success:
        print("did not get successfull http response")
    if outfile:
        outfile.close()


# some notes
# 
# Katello API doc: https://theforeman.org/plugins/katello/3.17/api/apidoc/v2.html
# list all hosts in Data Network (QTS) subnet in Katello: https://katello.example.com/hosts?search=subnet.name%3D%22Data+Network+%28QTS%29%22