#!/usr/bin/env python3

import getopt
import sys
import requests
import urllib3
import json
import os
from pprint import pprint
from requests.structures import CaseInsensitiveDict
from requests.auth import HTTPBasicAuth
import cmk.utils.password_store

def showUsage():
    sys.stderr.write("""CheckMK Nextcloud Special Agent

USAGE: agent_nextcloud_info -u [username] -p [password]
        OR
       agent_nextcloud_info -u [username] -t [token]
       agent_nextcloud_info -h

OPTIONS:
  -H, --hostname                Hostname (FQDN or IP) of Nextcloud server
  -u, --username                Username
  -p, --password                Password
  -P, --port                    Port
  -f, --folder                  Subfolder if not installed in web root
  -t, --token                   Token (recommended)
  --no-https True|False         If "True": Disable HTTPS, use HTTP (not recommended!)
  --no-cert-check True|False    If "True": Disable TLS certificate check (not recommended!)
  -h, --help                    Show this help message and exit
""")

# set this to true to produce debug output (this clutters the agent output)
# be aware: activating this logs very sensitive information to debug files in ~/tmp 
# !!DO NOT FORGET to delete these files after debugging is done!!

DEBUG = True

nc_api_endpoint = "ocs/v2.php/apps/serverinfo/api/v1/info?format=json"
nc_api_endpoint_all_users = "ocs/v1.php/cloud/users?format=json"
nc_api_endpoint_user = "ocs/v1.php/cloud/users"

opt_hostname = ""
opt_username = ""
opt_password = ""
opt_port = ""
opt_folder = ""
opt_token = "0"
opt_no_https = False
opt_no_cert_check = False

short_options = 'hH:u:p:P:f:t:'
long_options = [
    'hostname=', 'username=', 'password=', 'port=', 'token=', 'folder=', 'no-https=', 'no-cert-check=', 'help'
]

def logDebug(line):
    if DEBUG:
        home_path = os.getenv("HOME")
        tmp_path = f"{home_path}/tmp"
        help_file = f"{tmp_path}/nextcloud_{opt_hostname}_{opt_port}_debug.txt"
        with open(help_file, "a") as file:
            file.write(line)


def getOptions():
    global opt_hostname
    global opt_username
    global opt_password
    global opt_port
    global opt_folder
    global opt_token
    global opt_no_https
    global opt_no_cert_check

    opts, args = getopt.getopt(sys.argv[1:], short_options, long_options)
    for opt, arg in opts:
        if opt in ['-H', '--hostname']:
            opt_hostname = arg
        elif opt in ['-u', '--username']:
            opt_username = arg
        elif opt in ['-p', '--password']:
            opt_password = arg
        elif opt in ['-P', '--port']:
            opt_port = arg
        elif opt in ['-f', '--folder']:
            opt_folder = arg
        elif opt in ['-t', '--token']:
            opt_token = arg
        elif opt in ['--no-https']:
            if arg == 'True':
                opt_no_https = True
            else:
                opt_no_https = False
        elif opt in ['--no-cert-check']:
            if arg == 'True':
                opt_no_cert_check = True
            else:
                opt_no_cert_check = False
        elif opt in ['-h', '--help']:
            showUsage()
            sys.exit(0)
    logDebug(f"getOptions - Number of Arguments: {len(sys.argv)}, Argument List: {str(sys.argv)}\n")

def showOptions():
    print(f"Hostname: {opt_hostname}")
    print(f"Username: {opt_username}")
    print(f"Password: {opt_password}")
    print(f"Port: {opt_port}")
    print(f"Folder: {opt_folder}")
    print(f"Token: {opt_token}")
    print(f"No HTTPS: {opt_no_https}")
    print(f"No TLS Check: {opt_no_cert_check}")
    logDebug(f"showOptions - Hostname: {opt_hostname}, Port: {opt_port}, No HTTPS: {opt_no_https}, No Cert Check: {opt_no_cert_check}\n")

def createUrl(endpoint, hostname, protocol, port, folder):
    # these parameters are needed, otherwise no information about updates regarding apps and Nextcloud itself are not reported (since version 28)
    params = "skipApps=false&skipUpdate=false"
    if folder == "":
        url = f"{protocol}://{hostname}:{port}/{endpoint}"
    else:
        url = f"{protocol}://{hostname}:{port}/{folder}/{endpoint}"
    if endpoint == nc_api_endpoint:
        url = f"{url}&{params}"
    logDebug(f"createUrl - Data URL: {url}\n")
    return url

def createUrlUser(user, endpoint, hostname, protocol, port, folder):
    params = "format=json"
    if folder == "":
        url = f"{protocol}://{hostname}:{port}/{endpoint}/{user}?{params}"
    else:
        url = f"{protocol}://{hostname}:{port}/{folder}/{endpoint}/{user}?{params}"
    logDebug(f"createUrlUser - User URL: {url}\n")
    return url

def getSession(username, secret):
    session = requests.session()
    session.cookies.set("SameSite", "Strict")
    session.auth = (username, secret)
    session.headers['Accept'] = "application/json"
    return session

def getData(session, url, verify):
    headers = CaseInsensitiveDict()
    headers["Accept"] = "application/json"
    cookies = {"nc_sameSiteCookiestrict": "true"}
    response = session.get(url, headers=headers, cookies=cookies, verify=verify)
    status = response.status_code
    if (status == 200):
        jsdata = response.text
        data = json.loads(jsdata) # returns  a dictionary
        return data
    elif (status == 503):
        # this code is reported when maintenance mode is on
        sys.stderr.write(f"Request response code is {response.status_code} with URL {url}, maybe maintenance mode is on?\n")
        sys.exit(1)
    else:
        sys.stderr.write(f"Request response code is {response.status_code} with URL {url}\n")
        sys.exit(1)

def getDataAllUsers(session, url, verify):
    headers = CaseInsensitiveDict()
    headers["Accept"] = "application/json"
    headers["OCS-APIRequest"] = "true"
    cookies = {"nc_sameSiteCookiestrict": "true"}
    response = session.get(url, headers=headers, cookies=cookies, verify=verify)
    status = response.status_code
    if (status == 200):
        jsdata = response.text
        data = json.loads(jsdata) # returns  a dictionary
        return data
    else:
        sys.stderr.write(f"Request response code is {response.status_code} with URL {url}\n")
        sys.exit(1)

def getDataUser(session, url, verify):
    headers = CaseInsensitiveDict()
    headers["Accept"] = "application/json"
    headers["OCS-APIRequest"] = "true"
    cookies = {"nc_sameSiteCookiestrict": "true"}
    response = session.get(url, headers=headers, cookies=cookies, verify=verify)
    status = response.status_code
    if (status == 200):
        jsdata = response.text
        data = json.loads(jsdata) # returns  a dictionary
        return data
    else:
        sys.stderr.write(f"Request response code is {response.status_code} with URL {url}\n")
        sys.exit(1)
    
def doCmkOutput(data):
    print("<<<nextcloud_info:sep(59)>>>")  
    print(f"NC_Version;{data['ocs']['data']['nextcloud']['system']['version']}")
    print(f"NC_Freespace;{data['ocs']['data']['nextcloud']['system']['freespace']}")
    print(f"NC_Status;{data['ocs']['meta']['status']}")
    # This update info is available only from version 28 onwards, so the key "update" does not exist in all versions before
    try:
        print(f"NC_Last_Update;{data['ocs']['data']['nextcloud']['system']['update']['lastupdatedat']}")
        print(f"NC_Update_Available;{data['ocs']['data']['nextcloud']['system']['update']['available']}")
    except KeyError:
        pass
    print(f"NC_Num_Users;{data['ocs']['data']['nextcloud']['storage']['num_users']}")
    print(f"NC_Num_Files;{data['ocs']['data']['nextcloud']['storage']['num_files']}")
    print(f"NC_Num_Shares;{data['ocs']['data']['nextcloud']['shares']['num_shares']}")
    print(f"NC_Num_Storages;{data['ocs']['data']['nextcloud']['storage']['num_storages']}")
    print(f"NC_Num_Storages_Home;{data['ocs']['data']['nextcloud']['storage']['num_storages_home']}")
    print(f"NC_Num_Storages_Local;{data['ocs']['data']['nextcloud']['storage']['num_storages_local']}")
    print(f"NC_Num_Storages_Other;{data['ocs']['data']['nextcloud']['storage']['num_storages_other']}")
    # Workaround for Nextcloud 28.0.1 (KeyError "apps")
    try:
        print(f"NC_Num_Apps_Installed;{data['ocs']['data']['nextcloud']['system']['apps']['num_installed']}")
        print(f"NC_Num_Apps_Updates_Available;{data['ocs']['data']['nextcloud']['system']['apps']['num_updates_available']}")
    except KeyError:
        pass
    print(f"NC_Active_Users_Last_5Min;{data['ocs']['data']['activeUsers']['last5minutes']}")
    print(f"NC_Active_Users_Last_1Hour;{data['ocs']['data']['activeUsers']['last1hour']}")
    print(f"NC_Active_Users_Last_1Day;{data['ocs']['data']['activeUsers']['last24hours']}")
    print(f"NC_Webserver;{data['ocs']['data']['server']['webserver']}")
    print(f"NC_PHP_Version;{data['ocs']['data']['server']['php']['version']}")

    print("<<<nextcloud_database:sep(59)>>>")
    print(f"NC_Database_Type;{data['ocs']['data']['server']['database']['type']}")
    print(f"NC_Database_Version;{data['ocs']['data']['server']['database']['version']}")
    print(f"NC_Database_Size;{data['ocs']['data']['server']['database']['size']}")
    # opcache entry does not exist if opcache_get_status is disabled by server settings
    # thanks to Marcus Klein from Iteratio to report (and solve!) this bug
    if (data['ocs']['data']['server']['php']['opcache']):
        print(f"NC_OPCache_Hit_Rate;{data['ocs']['data']['server']['php']['opcache']['opcache_statistics']['opcache_hit_rate']}")
    else:
        print(f"NC_OPCache_Hit_Rate;0")

def doCmkOutputAllUsers(session, data, verify, hostname, protocol, port, folder):
    print("<<<nextcloud_users:sep(59)>>>")
    for user in data['ocs']['data']['users']:
        nc_url = createUrlUser(user, nc_api_endpoint_user, hostname, protocol, port, folder)
        user_data = getDataUser(session, nc_url, verify)
        userid = user_data['ocs']['data']['id']
        displayname = user_data['ocs']['data']['displayname']
        lastlogin = int(user_data['ocs']['data']['lastLogin'])
        if lastlogin == 0:
            # user has never logged in
            quota_free = -1
            quota_quota = -1
            quota_relative = -1
            quota_total = -1
            quota_used = -1
        else:
            quota_free = user_data['ocs']['data']['quota']['free']
            # quota_quota == -3 --> unlimited
            quota_quota = user_data['ocs']['data']['quota']['quota']
            # quota_relative = used * 100 / (free + used)
            quota_relative = user_data['ocs']['data']['quota']['relative']
            quota_total = user_data['ocs']['data']['quota']['total']
            quota_used = user_data['ocs']['data']['quota']['used']
        print(f"{userid};{displayname};{lastlogin};{quota_free};{quota_quota};{quota_relative};{quota_total};{quota_used}")

def main():
    # replace password from pwd store
    cmk.utils.password_store.replace_passwords()
    getOptions()
    if (opt_hostname == ""):
        sys.stderr.write(f"No hostname given.\n")
        showUsage()
        sys.exit(1)
    if (opt_no_cert_check):
        urllib3.disable_warnings(urllib3.exceptions.InsecureRequestWarning)
        verify = False
    else:
        verify = True
    if (opt_port == ""):     
        if (opt_no_https):
            protocol = "http"
            port = "80"
        else:
            protocol = "https"
            port = "443"
    else:
        if (opt_no_https):
            protocol = "http"
        else:
            protocol = "https"
        port = opt_port
    if DEBUG:
        showOptions()
    if (protocol == "http" and port == "443"):
        sys.stderr.write(f"Combining HTTP with port 443 is not supported.\n")
        sys.exit(1)
    if (protocol == "https" and port == "80"):
        sys.stderr.write(f"Combining HTTPS with port 80 is not supported.\n")
        sys.exit(1)
    if (opt_token == '0'):
        # authenticate with username and password
        pwd = opt_password
    else:
        # authenticate with token
        pwd = opt_token 

    # create session    
    session = getSession(opt_username, pwd)
    nc_url = createUrl(nc_api_endpoint, opt_hostname, protocol, port, opt_folder)
    nc_data = getData(session, nc_url, verify)
    doCmkOutput(nc_data)
    nc_url = createUrl(nc_api_endpoint_all_users, opt_hostname, protocol, port, opt_folder)
    nc_data = getDataAllUsers(session, nc_url, verify)
    doCmkOutputAllUsers(session, nc_data, verify, opt_hostname, protocol, port, opt_folder)

if __name__ == "__main__":
    main()