#!/usr/bin/env python3

import json
import requests
import configparser
import urllib3
from mako.template import Template
urllib3.disable_warnings()


def do_api_calls(config):
    data = {}

    #services
    request_url = "{}/v1/objects/services".format(config['icinga2_api']['baseurl'])
    headers = {
        'Accept': 'application/json',
        'X-HTTP-Method-Override': 'GET'
    }
    requestbody = {
        "attrs": [ "name", "state", "last_check_result", "host_name", "display_name" ],
        "joins": [ "host.name", "host.state", "host.last_check_result" ],
        "filter": config['filters']['services'],
    }
    r = requests.get(request_url,
        headers=headers,
        data=json.dumps(requestbody),
        auth=(config['icinga2_api']['username'], config['icinga2_api']['password']),
        verify=False)

    if (r.status_code == 200):
        data['services'] = r.json()
    else:
        r.raise_for_status()
    
    # hosts
    request_url = "{}/v1/objects/hosts".format(config['icinga2_api']['baseurl'])
    headers = {
        'Accept': 'application/json',
        'X-HTTP-Method-Override': 'GET'
    }
    requestbody = {
        "attrs": [ "name", "state" ],
        "filter": config['filters']['hosts'],
    }
    r = requests.get(request_url,
        headers=headers,
        data=json.dumps(requestbody),
        auth=(config['icinga2_api']['username'], config['icinga2_api']['password']),
        verify=False)

    if (r.status_code == 200):
        data['hosts'] = r.json()
    else:
        r.raise_for_status()
    
    return data

def render_text_output(data):
    print("{:50s} {:10s}".format("host", "status"))
    for host in data['hosts']['results']:
        print("{:50s} {}".format(host['name'], host['attrs']['state']))
    for service in data['services']['results']:
        print("{:50s} {}".format(service['name'], service['attrs']['state']))


def render_hosts(data):
    hosts_operational = ''
    hosts_warning = ''
    hosts_critical = ''

    hosts_operational_template = """
            <li class="list-group-item d-flex justify-content-between align-items-center">
                {}
                <span class="badge badge-success">OK</span>
            </li>
        """
    hosts_warning_template = """
            <li class="list-group-item d-flex justify-content-between align-items-center">
                {}
                <span class="badge badge-warning">WARNING</span>
            </li>
        """
    hosts_critical_template = """
            <li class="list-group-item d-flex justify-content-between align-items-center">
                {}
                <span class="badge badge-danger">CRITICAL</span>
            </li>
        """

    for host in data['hosts']['results']:
        if host['attrs']['state'] == 0:
            hosts_operational = hosts_operational + hosts_operational_template.format(host['name'])
        elif host['attrs']['state'] == 1:
            hosts_warning = hosts_warning + hosts_critical_template.format(host['name'])
        else:
            hosts_critical = hosts_critical + hosts_critical_template.format(host['name'])

    with open("hosts_template.html", "r") as f:
        htmlTemplate = f.read()
    htmlOutput = htmlTemplate.format(
        hosts_operational = hosts_operational,
        hosts_warning = hosts_warning,
        hosts_critical = hosts_critical,
    )
    return htmlOutput

def render_services_per_host(host, data):
    services_operational = ''
    services_warning = ''
    services_critical = ''
    card_header = ''

    services_template = """
            <li class="list-group-item d-flex justify-content-between align-items-center">
                {}
                <span class="badge badge-{}">{}</span>
            </li>
        """
    services_hostname_template = """<div class="card-header d-flex justify-content-between align-items-center"><h4>{}</h4> <span class="badge badge-success">OK</span></div>"""

    for service in sorted(data['services']['results'], key=lambda x: x['attrs']['display_name']):
        if service['attrs']['host_name'] == host:
            if service['attrs']['state'] == 0:
                services_operational = services_operational + services_template.format(service['attrs']['display_name'], 'success', 'OK')
            elif service['attrs']['state'] == 1:
                services_warning = services_warning + services_template.format(service['attrs']['display_name'], 'warning', 'WARNING')
            else:
                services_critical = services_critical + services_template.format(service['attrs']['display_name'], 'danger', 'CRITICAL')
            
            if service['joins']['host']['state'] == 0:
                card_header = services_hostname_template.format(host, 'success', 'UP')
            elif service['joins']['host']['state'] == 0:
                card_header = services_hostname_template.format(host, 'warning', 'WARNING')
            else:
                card_header = services_hostname_template.format(host, 'danger', 'DOWN')

    with open("services_template.html", "r") as f:
        htmlTemplate = f.read()

    htmlOutput = htmlTemplate.format(
        card_header = card_header,
        services_operational = services_operational,
        services_warning = services_warning,
        services_critical = services_critical
    )
    return htmlOutput

def render_service_details(data):
    # generate list of hosts by scanning services for unique host_name
    host_names = []
    for service in data['services']['results']:
        if service['attrs']['host_name'] not in host_names:
            host_names.append(service['attrs']['host_name'])
    # render html for each host_name
    html_output = ""
    for host in sorted(host_names):
        html_output = html_output + render_services_per_host(host, data)
    return html_output

def render_index_html(filename, host_summary, service_details):
    with open("template.html", "r") as f:
        htmlTemplate = f.read()

    htmlOutput = htmlTemplate.format(
        hosts = host_summary,
        services = service_details
    )

    with open(filename, "w") as f:
        f.write(htmlOutput)


def main():
    config = configparser.ConfigParser()
    config['icinga2_api'] = {
        'baseurl': 'https://localhost:5665',
        'username': 'root',
        'password': 'foobar'
    }
    with open('config.conf', 'r') as configfile:
        config.read('config.conf')
    data = do_api_calls(config)
    host_summary = render_hosts(data)
    service_details = render_service_details(data)
    render_index_html(config['output']['filename'], host_summary, service_details)

if __name__ == "__main__":
    main()