#!/bin/python3
import os
import sys
import logging
import requests
import json
import argparse

from subject import main
from lib.diffie_hellman import decrypt, encrypt

logging.basicConfig(format='%(levelname)s\t- %(message)s')
logger = logging.getLogger()
logger.setLevel(logging.INFO)

state = main(sys.argv)

BASE_DIR = os.path.join(os.path.expanduser('~'), '.sio/')

# session file - username(optional)
def list_subjects(args):

    parser = argparse.ArgumentParser()

    parser.add_argument("-k", '--key', nargs=1, help="Path to the key file")
    parser.add_argument("-r", '--repo', nargs=1, help="Address:Port of the repository")
    parser.add_argument("-v", '--verbose', help="Increase verbosity", action="store_true")

    parser.add_argument('session', nargs='?', default=None)
    parser.add_argument('username', nargs='?', default=None)

    args = parser.parse_args()

    # Check if session file is valid
    if args.session:
        if (not os.path.isfile(BASE_DIR + args.session)):
            logger.error("File '" + args.session + "' not found.")
            sys.exit(1)
    else:
        logger.error("Need session file.")
        sys.exit(1)

    # Get session file content
    with open(BASE_DIR + args.session, 'r') as f:
        args.session = json.load(f)

    payload = {}
    derived_key = bytes.fromhex(args.session['derived_key'])

    if args.username:
        payload['username'] = args.username[0]

    try:
        payload = json.dumps(payload)
        payload = encrypt(payload, derived_key).hex()

        headers = {
            'Authorization': args.session['token'],
            'Content-Type': 'application/octet-stream'
        }

        req = requests.get(f'http://{state['REP_ADDRESS']}/user/list',
                                            data=payload,
                                            headers=headers)
        req.raise_for_status()

    except requests.exceptions.HTTPError:
        logger.error("%d: %s", req.status_code, req.json()['error'])
        sys.exit(-1)

    except requests.exceptions.RequestException as errex:
        logger.error("Failed to obtain response from server.")
        sys.exit(-1)

    if req.status_code == 200:
        try:
            response_data = json.loads(decrypt(bytes.fromhex(req.text), derived_key).decode('utf-8'))
        except Exception:
            logger.error("Failed to decrypt the content")
            sys.exit(1)
        logger.info(json.dumps(response_data, indent=4))
        sys.exit(0)
    else:
        logger.error("Failed to get subjects")
        sys.exit(-1)
    
if __name__ == '__main__':
    list_subjects(sys.argv[1:])