#!/usr/bin/python3
"""
Add a list of UNIs to the target group
Replace current members if the replace flag is t (true)

Example:
    grouper_add_members.py -m dev -f <unilist> -g <group> -r <replace flag>
"""

import argparse
import requests
from requests.auth import HTTPBasicAuth
import json
import sys,string
import os

def grouperAddMembers(grouper_credentials, grouper_ws_uri, groupName, subject_list, replace_flag):
    """Add group member"""
    if replace_flag != 't' and replace_flag != 'f':
        print(f"replace flag {replace_flag} must be t or f")
        exit(1)

    # listOfSubjectDictionaries contains a list of dictionaries
    listOfSubjectDictionaries = []
    for nsubjects in range(0,len(subject_list)):
        listOfSubjectDictionaries.append({'subjectId':subject_list[nsubjects]})
    body = {
        "WsRestAddMemberRequest": {
            "wsGroupLookup": {
                "groupName": groupName
            },
            "replaceAllExisting": replace_flag,
            "subjectLookups": listOfSubjectDictionaries
        }
    }
    return grouperWSRequest(grouper_credentials, grouper_ws_uri+"/groups/"+groupName+"/members", "PUT", body)

def grouperGetUuid(grouper_credentials, grouper_ws_uri, groupName):
    """Get UUID for the specified group"""
    thisuuid = 0
    body = {
      "WsRestFindGroupsRequest": {
        "wsQueryFilter": {
          "groupName": groupName,
          "queryFilterType": "FIND_BY_GROUP_NAME_EXACT",
        }
      }
    }
    findGroups = grouperWSRequest(grouper_credentials, grouper_ws_uri+"/groups", "POST", body)
    if findGroups and findGroups['WsFindGroupsResults']['resultMetadata']['success'] and 'groupResults' in findGroups['WsFindGroupsResults']:
        thisuuid = findGroups['WsFindGroupsResults']['groupResults'][0]['uuid']
    return thisuuid

def grouperWSRequest(grouper_credentials, url, method, body=None):
    """Send a request to the Grouper Web Service."""
    try:
        response = requests.request(method, url, json=body, auth=grouper_credentials)
        response.raise_for_status()
    except requests.RequestException as e:
        raise SystemExit(e) from None

    return response.json()

def add_members(mode, uni_list, group_id_path, replace_flag):
    """Add a list of UNIs to a group.

    Args:
        mode (str): The environment mode ('dev', 'prod').
        uni_list (str): The UNI file name.
        group_id_path (str): The group to be updated.
        replace_flag (str): The replace flag ('t', 'f').
    """
    # set the Grouper Web Service username and password
    grouper_username = 'abc1234'
    grouper_password = 'xxxxxxxxxxxxxxxxxxxx'
    grouper_credentials = HTTPBasicAuth(grouper_username,grouper_password)

    # the Grouper Web Service URI should point to dev or prod Grouper
    devGrouperURI  = 'https://grouper-dev.cc.columbia.edu/grouper-ws/servicesRest/v2_4_000'
    prodGrouperURI = 'https://grouper.cc.columbia.edu/grouper-ws/servicesRest/v2_4_000'
    if mode == 'prod':
        grouper_ws_uri = prodGrouperURI
    else:
        grouper_ws_uri = devGrouperURI

    # Verify that the target group exists and is accessible by this user
    if grouperGetUuid(grouper_credentials,grouper_ws_uri,group_id_path) == 0:
        print(f"{group_id_path} group not found (does not exist or is not accessible)")
        return

    # Verify that the file exists
    if not os.path.exists(uni_list):
        print(f"input file not found: {uni_list}")
        return

    # Read the list of UNIs from the input file
    infil = open(uni_list, 'r')
    subject_list = []
    while 1:
        line = infil.readline()
        if not line:
            break
        line = line.rstrip() # remove the newline character
        subject_list.append(line) # add this UNI to the list
    infil.close()

    # Add the members to the group
    result = grouperAddMembers(grouper_credentials,grouper_ws_uri,group_id_path,subject_list,replace_flag)
    if (
        not result
        or not result['WsAddMemberResults']['results'][0]['resultMetadata']['success']
    ):
        print(f"Unable to add members to {group_id_path}")
        return

    print(f"UNIs have been added to {group_id_path}")

def main():
    """Parses command-line arguments and calls add_member."""
    parser = argparse.ArgumentParser(
        description="Add a list of UNIs to the specified group.",
        epilog=("Replace current members if the replace flag is t (true)."),
    )
    parser.add_argument(
        "-m",
        action="store",
        dest="mode",
        required=True,
        choices=["dev", "prod"],
        type=str.lower,
        help="the Grouper environment mode",
    )
    parser.add_argument(
        "-f",
        action="store",
        dest="uni_list",
        required=True,
        help="UNI file name",
    )
    parser.add_argument(
        "-g",
        action="store",
        dest="group_id_path",
        required=True,
        help="the group ID path of the group to be updated",
    )
    parser.add_argument(
        "-r",
        action="store",
        dest="replace_flag",
        required=True,
        choices=["t", "f"],
        type=str.lower,
        help="replace flag",
    )
    args = parser.parse_args()

    add_members(args.mode, args.uni_list, args.group_id_path, args.replace_flag)

if __name__ == "__main__":
    main()