#!/usr/bin/env python3

import getopt
import sys
import requests
import urllib3
import json
import os
import cmk.utils.password_store
from pprint import pprint
from requests.structures import CaseInsensitiveDict
from requests.auth import HTTPBasicAuth
from time import (
    time, localtime, strftime,
)

def showUsage() -> None:
    sys.stderr.write("""CheckMK Mailcow Special Agent

USAGE: agent_nextcloud -H [hostname] -k [apikey]
       agent_nextcloud -h

OPTIONS:
  -H, --hostname                Hostname (FQDN or IP) of Nextcloud server
  -k, --apikey                  API Key
  -P, --port                    Port
  --check-version True|False    If "True": Running version will be checked against official Github repo
  --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 = False

mc_api_base = "api/v1/get"

opt_hostname = ""
opt_apikey = ""
opt_port = ""
opt_check_version = False
opt_no_https = False
opt_no_cert_check = False

short_options = 'hH:k:P:'
long_options = [
    'hostname=', 'apikey=', 'port=', 'check-version=', 'no-https=', 'no-cert-check=', 'help'
]

domain_data = {}
mailbox_data = {}

debugLogFilename = ""
SEP = "|"
#SEP = "\t"
TIMEFMT = "%Y-%m-%d %H:%M:%S"
FLOATFMT = "{:.4f}"

'''
Decorator function for debugging purposes
    creates a file with many information regarding the function call, like:
        timestamp
        name of function
        runtime
        number of arguments
        number of keyword arguments
        return value of function call
        type of return value
        all parameters given to function
'''
def debugLog(function):
    def wrapper(*args, **kwargs):
        # execute function and measure runtime
        start = time()
        value = function(*args, **kwargs)
        end = time()
        # get number of args and kwargs
        len_args = len(args)
        len_kwargs = len(kwargs)
        # format the output
        seconds = FLOATFMT.format(end - start)
        local_time = strftime(TIMEFMT,localtime(start))
        # get function name
        fname = function.__name__
        # create output
        # out1: Timestamp|Name of Function|Runtime|Num Args|Num Kwargs|Return Value|Return Value Type
        out1 = f"{local_time}{SEP}{fname}{SEP}{seconds}{SEP}{len_args}{SEP}{len_kwargs}{SEP}{value}{SEP}{type(value)}"
        # out2: all arguments
        out2 = ""
        for arg in args:
            out2 = out2 + SEP + str(arg)
        # out3: all keyword arguments
        out3 = ""
        if len_kwargs > 0:
            for key, val in kwargs.items():
                out3 = out3 + SEP + key + ":" + str(val)
        # write output to file
        if debugLogFilename != "":
            try:
                with open(debugLogFilename, "a+") as f:
                    f.write(f"{out1}{out2}{out3}\n")
            except:
                sys.stderr.write(f"Something went wrong when writing to file {debugLogFilename}\n")
                sys.exit(1)
        else:
            sys.stderr.write(f"Debug activated, but no debug filename given.\n")
            sys.exit(1)
        return value
    return wrapper


def getDebugFilename(hostname: str) -> str:
    home_path = os.getenv("HOME")
    tmp_path = f"{home_path}/tmp"
    file_name = f"{tmp_path}/mailcow_{hostname}_debug.log"
    return file_name


def getOptions() -> None:
    global opt_hostname
    global opt_apikey
    global opt_port
    global opt_check_version
    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 ['-k', '--apikey']:
            opt_apikey = arg
        elif opt in ['-P', '--port']:
            opt_port = arg
        elif opt in ['--check-version']:
            if arg == 'True':
                opt_check_version = True
            else:
                opt_check_version = False
        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)
    if DEBUG:
        home_path = os.getenv("HOME")
        tmp_path = f"{home_path}/tmp"
        help_file = f"{tmp_path}/mailcow_{opt_hostname}_debug.txt"
        with open(help_file, "a") as file:
            file.write(f"Number of Arguments: {len(sys.argv)}, Argument List: {str(sys.argv)}\n")


#@debugLog
def showOptions() -> None:
    print(f"Hostname: {opt_hostname}")
    print(f"Username: {opt_apikey}")
    print(f"Port: {opt_port}")
    print(f"Check Version: {opt_check_version}")
    print(f"No HTTPS: {opt_no_https}")
    print(f"No TLS Check: {opt_no_cert_check}")
    home_path = os.getenv("HOME")
    tmp_path = f"{home_path}/tmp"
    help_file = f"{tmp_path}/mailcow_{opt_hostname}_debug.txt"
    with open(help_file, "a") as file:
        file.write(f"Hostname: {opt_hostname}, Port: {opt_port}, No HTTPS: {opt_no_https}, No Cert Check: {opt_no_cert_check}\n")

#@debugLog
def getDomainInfo(headers: str, verify: bool, base_url: str) -> int:
    url = f"{base_url}/domain/all"
    response = requests.get(url, headers=headers, verify=verify)
    if (response.status_code == 200):
        jsdata = response.text
        data = json.loads(jsdata)   # returns a list of dictionaries
        i = 0
        while i < len(data):
            #pprint(data[i])
            # get domain name and status (active (1) or not (0))
            domain_name = data[i].get("domain_name")
            active = data[i].get("active")
            # get creation and last modification date
            created = data[i].get("created")
            modified = data[i].get("modified")      # returns "None" or date
            # get maximum and current number of mailboxes in this domain
            max_num_mboxes_for_domain = data[i].get("max_num_mboxes_for_domain")
            mboxes_in_domain = data[i].get("mboxes_in_domain")
            # get maximum and current number of aliases in this domain
            max_num_aliases_for_domain = data[i].get("max_num_aliases_for_domain")
            aliases_in_domain = data[i].get("aliases_in_domain")
            # get total messages in this domain
            msgs_total = data[i].get("msgs_total")
            # get total bytes used in this domain
            bytes_total = data[i].get("bytes_total")
            # get maximum quota for this domain
            max_quota_for_domain = data[i].get("max_quota_for_domain")
            # store all domain data in global dictionary
            dom = {
                "active": active,
                "created": created,
                "modified": modified,
                "max_num_mboxes_for_domain": max_num_mboxes_for_domain,
                "mboxes_in_domain": mboxes_in_domain,
                "max_num_aliases_for_domain": max_num_aliases_for_domain,
                "aliases_in_domain": aliases_in_domain,
                "msgs_total": msgs_total,
                "bytes_total": bytes_total,
                "max_quota_for_domain": max_quota_for_domain
            }
            domain_data[domain_name] = {}
            domain_data[domain_name] = dom
            i += 1
        # return number of email domains
        return i
    else:
        sys.stderr.write(f"Request response code is {response.status_code} with URL {url}\n")
        sys.exit(1)

#@debugLog
def getMailboxInfo(headers: str, verify: bool, base_url: str) -> tuple:
    url = f"{base_url}/mailbox/all"
    response = requests.get(url, headers=headers, verify=verify)
    if (response.status_code == 200):
        jsdata = response.text
        data = json.loads(jsdata)   # returns a list of dictionaries
        i = 0
        global_num_messages = 0
        while i < len(data):
            # get status of mailbox (0-->inactive or 1-->active)
            active = data[i].get("active")
            # get username of mailbox
            username = data[i].get("username")
            # get friendly name of user
            name = data[i].get("name")
            # get number of messages in mailbox
            num_messages = data[i].get("messages")
            # get quota used in percent (rounded to full percent)
            percent_in_use = data[i].get("percent_in_use")
            # get quota and quota used in bytes
            quota = data[i].get("quota")
            quota_used = data[i].get("quota_used")
            # get creation and last modification date
            created = data[i].get("created")
            modified = data[i].get("modified")
            # get number of messages
            messages = data[i].get("messages")
            # get last login dates
            last_imap_login = data[i].get("last_imap_login")
            last_pop3_login = data[i].get("last_pop3_login")
            last_smtp_login = data[i].get("last_smtp_login")
            mb = {
                "active": active,
                "created": created,
                "modified": modified,
                "name": name,
                "num_messages": num_messages,
                "percent_in_use": percent_in_use,
                "quota": quota,
                "quota_used": quota_used,
                "messages": messages,
                "last_imap_login": last_imap_login,
                "last_pop3_login": last_pop3_login,
                "last_smtp_login": last_smtp_login
            }
            mailbox_data[username] = {}
            mailbox_data[username] = mb
            i += 1
            global_num_messages += num_messages
        # return number of mailboxes and global number of messages
        return i, global_num_messages
    else:
        sys.stderr.write(f"Request response code is {response.status_code} with URL {url}\n")
        sys.exit(1)

def getGitVersion() -> str:
    url = "https://api.github.com/repos/mailcow/mailcow-dockerized/releases/latest"
    git_version = ""
    response = requests.get(url)
    if (response.status_code == 200):
        jsdata = response.text
        data = json.loads(jsdata)   # returns a dictionary
        git_version = data["tag_name"]
        #print(git_version)
    else:
        sys.stderr.write(f"Request response code is {response.status_code} with URL {url}\n")
        sys.exit(1)
    return git_version

def compareVersions(mc_ver: str, git_ver: str) -> bool:
    update_available = False
    try:
        mc_year, mc_month = mc_ver.split("-")
        git_year, git_month = git_ver.split("-")
        #print(mc_year, mc_month, git_year, git_month)
        mc_year_int = int(mc_year)
        git_year_int = int(git_year)
        if git_year_int > mc_year_int:
            update_available = True
        else:
            len_mc_month = len(mc_month)
            len_git_month = len(git_month)
            if len_mc_month == 2:
                mc_month_int = int(mc_month)
            elif len_mc_month == 3:
                mc_month_int = int(mc_month[0:2])
                mc_month_ver = mc_month[-1]
            else:
                pass
            if len_git_month == 2:
                git_month_int = int(git_month)
            elif len_git_month == 3:
                git_month_int = int(git_month[0:2])
                git_month_ver = git_month[-1]
            else:
                pass
            if git_month_int > mc_month_int:
                update_available = True
            elif len_mc_month == 2 and len_git_month == 3:
                update_available = True
            elif git_month_ver > mc_month_ver:
                update_available = True
    except:
        pass
    return update_available

#@debugLog
def getMailcowInfo(headers: str, verify: bool, base_url: str) -> dict:
    info_data = {}
    url = f"{base_url}/status/version"
    response = requests.get(url, headers=headers, verify=verify)
    if (response.status_code == 200):
        jsdata = response.text
        data = json.loads(jsdata)   # returns a dictionary
        #pprint(data)
        # get Mailcow version
        mc_version = data["version"]
        # if enabled, check this version against the official Mailcow repo on Github
        if opt_check_version:
            git_version = getGitVersion()
            update_available = compareVersions(mc_version, git_version)
            #update_available = compareVersions("2023-01a", "2023-02")
            #print(update_available)
            info_data["git_version"] = git_version
            info_data["update_available"] = update_available
        else:
            info_data["git_version"] = "Version check disabled"
            info_data["update_available"] = False
        info_data["mc_version"] = mc_version
        info_data["check_version_enabled"] = opt_check_version
        return info_data
    else:
        sys.stderr.write(f"Request response code is {response.status_code} with URL {url}\n")
        sys.exit(1)

#@debugLog
def getSolrInfo(headers: str, verify: bool, base_url: str) -> tuple:
    url = f"{base_url}/status/solr"
    response = requests.get(url, headers=headers, verify=verify)
    if (response.status_code == 200):
        jsdata = response.text
        data = json.loads(jsdata)   # returns a dictionary
        #pprint(data)
        # get Solr infos
        solr_enabled = data["solr_enabled"]
        solr_size = data["solr_size"]
        solr_documents = data["solr_documents"]
        return solr_enabled, solr_size, solr_documents
    else:
        sys.stderr.write(f"Request response code is {response.status_code} with URL {url}\n")
        sys.exit(1)


'''
Output is as follows:
0   mailbox name                email address used for login
1   active                      1 --> active, 0 --> not active
2   creation date               "None" if ???
3   last modified date          "None" if never modified
4   name                        display name
5   number of messages
6   percent in use              quota used, rounded to full percents
7   quota                       max quota in bytes
8   quota used                  quota used in bytes
9   last imap login             seconds since epoch, 0 if never logged in
10  last pop3 login             seconds since epoch, 0 if never logged in
11  last smtp login             seconds since epoch, 0 if never logged in

Example:
user1@dom1.de;1;2022-04-29 14:29:34;2022-04-29 14:29:34;Sarah;2433;2;21474836480;495481374;1692520168;0;1692281537
user2@dom1.de;1;2022-04-29 14:38:33;2022-04-29 14:38:33;Tom;271;0;21474836480;25895752;1657394782;1692519758;1681065713
user1@dom2.de;1;2022-04-30 09:55:37;2022-04-30 09:55:37;Melissa;53460;33;19964887040;6677677548;1692520066;0;1692510822
'''

#@debugLog
def doCmkOutputMailboxes() -> None:
    print("<<<mailcow_mailboxes:sep(59)>>>")
    for mb in mailbox_data:
        active = mailbox_data[mb]["active"]
        created = mailbox_data[mb]["created"]
        modified = mailbox_data[mb]["modified"]
        name = mailbox_data[mb]["name"]
        # strip semicolons, if present, since we use it as delimiter 
        name = name.replace(";", "")
        num_messages = mailbox_data[mb]["num_messages"]
        percent_in_use = mailbox_data[mb]["percent_in_use"]
        quota = mailbox_data[mb]["quota"]
        quota_used = mailbox_data[mb]["quota_used"]
        last_imap_login = mailbox_data[mb]["last_imap_login"]
        last_pop3_login = mailbox_data[mb]["last_pop3_login"]
        last_smtp_login = mailbox_data[mb]["last_smtp_login"]
        print(f"{mb};{active};{created};{modified};{name};{num_messages};{percent_in_use};{quota};{quota_used};{last_imap_login};{last_pop3_login};{last_smtp_login}")

#@debugLog
def doCmkOutputMailcow(version: str, 
        num_domains: int, num_mailboxes: int, num_global_messages: int,
        solr_enabled: bool, solr_size: float, solr_documents: int,
        git_version: str, update_available: bool, check_version_enabled: bool
    ) -> None:
    print("<<<mailcow_info:sep(59)>>>")
    # strip semicolons, if present, since we use it as delimiter
    version = version.replace(";", "")
    print(f"{version};{num_domains};{num_mailboxes};{num_global_messages};{solr_enabled};{solr_size};{solr_documents};{git_version};{update_available};{check_version_enabled}")


'''
Output is as follows:
0   domain_name
1   active                      1 --> active, 0 --> not active
2   creation date               "None" if ???
3   last modified date          "None" if never modified
4   max number mailboxes
5   number of mailboxes
6   max number of aliases
7   number of aliases
8   total number of messages
9   total number of bytes used  in bytes
10  max quota                   in bytes

Example:
dom1.de;1;2022-04-23 22:54:57;None;10;0;400;6;0;0;10737418240
dom2.de;1;2022-04-29 13:38:42;2023-08-19 17:21:04;10;0;400;2;0;0;10737418240
dom3.de;1;2022-04-29 13:36:08;2022-04-29 21:26:19;10;1;100;3;28132;12852485367;21474836480
'''

#@debugLog
def doCmkOutputDomains() -> None:
    print("<<<mailcow_domains:sep(59)>>>")
    for dom in domain_data:
        active = domain_data[dom]["active"]
        created = domain_data[dom]["created"]
        modified = domain_data[dom]["modified"]
        max_num_mboxes_for_domain = domain_data[dom]["max_num_mboxes_for_domain"]
        mboxes_in_domain = domain_data[dom]["mboxes_in_domain"]
        max_num_aliases_for_domain = domain_data[dom]["max_num_aliases_for_domain"]
        aliases_in_domain = domain_data[dom]["aliases_in_domain"]
        msgs_total = domain_data[dom]["msgs_total"]
        bytes_total = domain_data[dom]["bytes_total"]
        max_quota_for_domain = domain_data[dom]["max_quota_for_domain"]
        print(f"{dom};{active};{created};{modified};{max_num_mboxes_for_domain};{mboxes_in_domain};{max_num_aliases_for_domain};{aliases_in_domain};{msgs_total};{bytes_total};{max_quota_for_domain}")


def main():
    global debugLogFilename
    cmk.utils.password_store.replace_passwords()
    getOptions()
    # do some parameter checks
    if (opt_hostname == ""):
        sys.stderr.write(f"No hostname given.\n")
        showUsage()
        sys.exit(1)
    else:
        hostname = opt_hostname
    if (opt_apikey == ""):
        sys.stderr.write(f"No API key given.\n")
        showUsage()
        sys.exit(1)
    if (opt_no_cert_check):
        # disable certificate warnings
        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 (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)
    headers = CaseInsensitiveDict()
    headers["Accept"] = "application/json"
    headers["X-API-Key"] = opt_apikey
    # now "hostname" contains the FQDN of the host running Mailcow
    # now "protocol" is http or https
    # now "port" contains the port number to use
    # now "verify" signals whether certificate checking will be done (True) or not (False)
    # now "headers" contains the accepted format (JSON) and the API key to use
    debugLogFilename = getDebugFilename(hostname)
    if DEBUG:
        showOptions()
        print(f"hostname: {hostname}, protocol: {protocol}, port: {port}, verify: {verify}")
    base_url = f"{protocol}://{hostname}:{port}/{mc_api_base}"
    # get domain data
    num_domains = getDomainInfo(headers, verify, base_url)
    # get mailbox data
    num_mailboxes, num_global_messages = getMailboxInfo(headers, verify, base_url)
    # get global Mailcow info
    solr_enabled, solr_size, solr_documents = getSolrInfo(headers, verify, base_url)
    mailcow_info = getMailcowInfo(headers, verify, base_url)
    mailcow_version = mailcow_info["mc_version"]
    github_version = mailcow_info["git_version"]
    update_available = mailcow_info["update_available"]
    check_version_enabled = mailcow_info["check_version_enabled"]
    # create agent output
    doCmkOutputDomains()
    doCmkOutputMailboxes()
    doCmkOutputMailcow(mailcow_version, 
        num_domains, num_mailboxes, num_global_messages,
        solr_enabled, solr_size, solr_documents,
        github_version, update_available, check_version_enabled
    )


if __name__ == "__main__":
    main()