#!/usr/bin/env python
# -*- coding: utf-8 -*-

# Copyright (C) 2009 Michel Blockelet <blockelet@crans.org>

# This file is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# This file is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 59 Temple Street #330, Boston, MA 02111-1307, USA.

"""Plugin munin pour innd :: donne le nombre total de posts par newsgroup."""

## Importations
import socket, sys, threading, time

## Configuration
# Fichier de cache pour stocker les données entre deux lancements
cache_file = "/tmp/munin_innd_total_cache"
# Effectuer le compte exact du nombre de messages (beaucoup plus lent)
# sinon, utilise le compte approximatif envoyé par le serveur
exact_count = False
# Nombre de messages minimal pour être affiché
min_messages = 100

def recvlines(sock):
    buff = sock.recv(4096)
    while buff[-3] != '.':
        buff += sock.recv(4096)
    return buff.split('\r')[:-2]


def get_newsgroups_data():
    ## Connexion
    s = socket.socket()
    s.connect(('localhost', 119))

    ## Mise en mode reader (pour utiliser 'listgroup')
    s.send("mode reader\r\n")

    # Petit "hack" en attendant d'utiliser la nntplib
    time.sleep(0.5)

    s.recv(4096)

    ## Récupération des newsgroups et du nombre de posts
    s.send("list\r\n")
    newsgroups = []
    for l in recvlines(s)[1:]:
        name = l.split()[0]

        # Conversion du nom vers un format accepté par munin
        cname = name
        while '.' in cname:
            (parent, sep, sub) = cname.partition('.')
            cname = '%s_%s' % (parent[0], sub)
        cname = cname.replace('-', '_')

        # Récupération du nombre de posts
        if exact_count:
            s.send('listgroup %s\r\n' % name)
            val = len(recvlines(s))
        else:
            s.send('group %s\r\n' % name)
            val = int(s.recv(4096).split()[1])

        # On ne garde pas les newsgroups presque vides
        if val > min_messages:
            newsgroups.append((name, cname, val))

    ## On garde un cache si jamais le serveur nous bounce
    if len(newsgroups) > 0:
        try:
            f = open(cache_file, 'w')
            for ngdata in newsgroups:
                f.write('%s,%s,%d\n' % ngdata)
            f.close()
        except:
            pass
    else:
        try:
            for line in open(cache_file, 'r'):
                newsgroups.append(line.strip().split(','))
        except:
            pass

    return newsgroups


## Sortie
if len(sys.argv) > 1 and sys.argv[1] == 'config':
    # Configuration du graphe
    print 'host_name news.crans.org'
    print 'graph_title Nombre total de posts'
    print 'graph_args --base 1000 --lower-limit 0'
    print 'graph_vlabel posts'
    print 'graph_category News'
    print 'graph_info Nombre de posts pour chaque newsgroup'
    rnewsgroups = get_newsgroups_data()
    (ng0, cng0, val0) = rnewsgroups[0]
    print '%s.label %s' % (cng0, ng0)
    print '%s.draw AREA' % cng0
    for (ng, cng, val) in rnewsgroups[1:]:
        print '%s.label %s' % (cng, ng)
        print '%s.draw STACK' % cng
    print 'total.label Total'
else:
    # On lance un thread pour éviter les timeouts
    finished = threading.Event()

    def thread_gnd(return_newsgroups, finished):
        return_newsgroups.extend(get_newsgroups_data())
        finished.set()

    rnewsgroups = []
    t = threading.Thread(target=thread_gnd, args=(rnewsgroups, finished))
    t.daemon = True
    t.start()

    # On laisse 30 secondes pour que le thread finisse
    finished.wait(30)
    if finished.isSet():
        fnewsgroups = rnewsgroups
    else:
        try:
            for line in open(cache_file, 'r'):
                fnewsgroups.append(line.strip().split(','))
        except:
            fnewsgroups = []

    # Envoi des valeurs
    lines = []
    total = 0
    for (ng, cng, val) in fnewsgroups:
        total += val
        print '%s.value %d' % (cng, val)
    print 'total.value %d' % total