import argparse
import json
import os
import requests
import time

DEBUG = False


class colors:
    HEADER = '\033[95m'
    OKBLUE = '\033[94m'
    OKCYAN = '\033[96m'
    OKGREEN = '\033[92m'
    WARNING = '\033[93m'
    FAIL = '\033[91m'
    ENDC = '\033[0m'
    BOLD = '\033[1m'
    UNDERLINE = '\033[4m'


def headline(color: bool) -> str:
    rv = ""
    if color:
        rv += colors.BOLD + colors.UNDERLINE
    rv += "NAGIOS Status:"
    if color:
        rv += colors.ENDC
    rv += "\n\n"
    return rv


class nagios_service(dict):
    SID_OK = 2
    SID_WARNING = 4
    SID_ERROR = 16
    #
    SNAME_OK = "OKAY"
    SNAME_FLAPPING = "FLAPPING"
    SNAME_WARNING = "WARNING"
    SNAME_ERROR = "ERROR"
    SNAME_UNKNOWN = "UNKNOWN"
    TIMEFORMAT = "%d.%m.%Y %H:%M"

    def __init__(self, service_dict) -> None:
        super().__init__(service_dict)

    def is_problem(self):
        return self["status"] != self.SID_OK or self.flapping()

    def host_name(self):
        return self['host_name']

    def name(self):
        return self['description']

    def status(self):
        status = self["status"]
        default = self.SNAME_UNKNOWN
        if status == self.SID_OK and self.flapping():
            return self.SNAME_FLAPPING
        return {
            self.SID_OK: self.SNAME_OK,
            self.SID_WARNING: self.SNAME_WARNING,
            self.SID_ERROR: self.SNAME_ERROR
        }.get(status, default)

    def last_okay(self):
        return time.strftime(self.TIMEFORMAT, time.localtime(self["last_time_ok"] / 1000))

    def info(self):
        return self.get("plugin_output") or self.get("long_plugin_output")

    def flapping(self):
        return self["is_flapping"]

    def __color__(self):
        return {
            self.SNAME_OK: colors.OKGREEN,
            self.SNAME_FLAPPING: colors.OKBLUE,
            self.SNAME_WARNING: colors.WARNING,
            self.SNAME_ERROR: colors.FAIL,
            self.SNAME_UNKNOWN: colors.OKCYAN
        }.get(self.status())

        return colors.OKBLUE

    def __head__(self, color=False):
        rv = headline(color)
        rv += "+-----------------------------------------------------------------------------------------\n"
        rv += "| Host                      | Service Name    | State    | Last time Okay   |\n"
        rv += "+---------------------------+-----------------+----------+------------------+-------------\n"
        return rv

    def __foot__(self):
        return "+---------------------------+-----------------+----------+------------------+-------------\n"

    def __str__(self, color=False):
        cols = []
        cols.append((self.host_name, 25, False))
        cols.append((self.name, 15, color))
        cols.append((self.status, 8, color))
        cols.append((self.last_okay, 16, color))
        cols.append((self.info, 0, False))
        #
        rv = ""
        for txt_method, l, c in cols:
            txt = txt_method()
            if len(rv) > 0:
                rv += " | "
            if c:
                if txt_method == self.last_okay:
                    rv += colors.OKGREEN
                else:
                    rv += self.__color__()
            if l > 0:
                rv += txt[:l]
                rv += " " * (l-len(txt))
            else:
                rv += txt
            if c:
                rv += colors.ENDC
        #
        rv = "| " + rv + "\n"
        if DEBUG:
            rv += json.dumps(self, indent=4, sort_keys=True)
        return rv


class __nagios_status__(dict):
    def __init__(self) -> None:
        super().__init__()

    def all_problems(self):
        rv = __nagios_status__()
        for host in self:
            for service in self[host]:
                if service.is_problem():
                    rv.__add_service__(host, service)
        return rv

    def __add_service__(self, host, service):
        if host not in self:
            self[host] = []
        self[host].append(nagios_service(service))

    def __str__(self, color=False) -> str:
        rv = ""
        for host in self:
            for service in self[host]:
                if len(rv) == 0:
                    rv += service.__head__(color=color)
                rv += service.__str__(color=color)
        if len(rv) > 0:
            rv += service.__foot__()
        else:
            rv += headline(color)
            rv += "No monitorings to be reported."
        return rv + "\n"


class nagios_status(__nagios_status__):
    URL = "nagios4/cgi-bin/statusjson.cgi?query=servicelist&details=true"  # &servicestatus=warning"
    KEY_DATA = 'data'
    KEY_SERVICELIST = 'servicelist'

    def __init__(self, host, secure) -> None:
        super().__init__()
        #
        if secure:
            prefix = "https://"
        else:
            prefix = "http://"
        r = requests.get(os.path.join(prefix, host, self.URL))
        data = r.json()

        hosts = data.get(self.KEY_DATA, {}).get(self.KEY_SERVICELIST, {})
        for host in hosts:
            for service in hosts.get(host, {}):
                self.__add_service__(host, hosts.get(host).get(service))


if __name__ == "__main__":
    parser = argparse.ArgumentParser(description="Returns the status of all or partial nagios monitorings.")
    parser.add_argument("hostname", help="The hostname and port of the nagios server (e.g. nagios:8080)")
    parser.add_argument("-a", "--all", action="store_true", default=False,
                        help="print the status of all nagios monitorings. Default is all problems.")
    parser.add_argument("-s", "--secure", action="store_true", default=False, help="Enables secure connection (https)")
    parser.add_argument("-m", "--monochrome", action="store_true", default=False, help="No colored output")
    args = parser.parse_args()
    #
    try:
        s = nagios_status(args.hostname, args.secure)
    except requests.ConnectionError:
        print(headline(not args.monochrome) + "Can not connect to given host.")
    else:
        if args.all:
            print(s.__str__(color=not args.monochrome))
        else:
            print(s.all_problems().__str__(color=not args.monochrome))