#!/usr/bin/python

import ConfigParser
import json
import os
from os import path
import socket
import sys
import urllib2

import psutil

is_root = (os.getuid() == 0)
config = ConfigParser.RawConfigParser()
if is_root:
	cfg_path = '/etc/sysvitals.cfg'
else:
	cfg_path = path.join(path.dirname(path.abspath(__file__)), 'sysvitals.cfg')
default_api_server = 'http://api.sysvitals.com'

def post():
	if not config.read(cfg_path):
		sys.exit('no config found at %s' % cfg_path)

	cpu = psutil.cpu_times()
	mem = psutil.virtual_memory()
	net = psutil.net_io_counters()
	disk = psutil.disk_io_counters()
	datum = {
		'cpu': cpu._asdict(),
		'mem': {
			'total': mem.total,
			'used': mem.used,
			'buffers': mem.buffers,
			'cached': mem.cached,
		},
		'net': net._asdict(),
		'disk': {
			'read_bytes': disk.read_bytes,
			'write_bytes': disk.write_bytes,
		},
	}
	datum['cpu']['num_cpus'] = psutil.NUM_CPUS
	for partition in psutil.disk_partitions():
		usage = psutil.disk_usage(partition.mountpoint)
		datum['disk'][partition.mountpoint] = {
			'total': usage.total,
			'used': usage.used,
		}

	api_key = config.get('client', 'api_key')
	group_id = config.get('client', 'group_id')
	server_id = config.get('client', 'server_id')
	from pprint import pprint
	pprint(datum)
	#__query(group_id, 'datum/' + server_id, api_key, datum)

def configure():
	if not is_root:
		print 'configuring sysvitals client not as root will create a local config'
		if raw_input('are you sure you want to continue? [y/N] ') != 'y':
			return
	if path.exists(cfg_path):
		print cfg_path, 'already exists'
		if raw_input('are you sure you want to continue? [y/N] ') != 'y':
			return

	config.add_section('client')
	config.set('client', 'api_server', default_api_server)
	group_id = None
	while group_id is None:
		group_id = raw_input('group_id: ')
		try:
			int(group_id)
		except ValueError:
			group_id = None
			print 'group_id should be numeric'
	config.set('client', 'group_id', group_id)
	api_key = raw_input('api_key: ')
	config.set('client', 'api_key', api_key)

	print 'checking existing servers'
	servers = __query(group_id, 'servers', api_key)
	our_hostname = socket.gethostname()
	server_id = None
	matches = 0
	for server in servers:
		if server['hostname'] == our_hostname:
			server_id = server['id']
			matches += 1
	if matches == 0:
		print 'no hostname matches found'
	elif matches == 1:
		print '1 hostname match found (%s, server id %d)' % (our_hostname, server_id)
		if raw_input('take over this server id? (only do this if the old host is dead) [y/N] ') != 'y':
			server_id = None
	else:
		print 'found %d servers with the same hostname... hopefully this is ok...' % matches
		server_id = None

	if server_id is None:
		print 'getting a brand new server id'
		response = __query(group_id, 'register_server', api_key, {'hostname': our_hostname})
		server_id = response['server_id']
	config.set('client', 'server_id', server_id)

	print 'writing config to', cfg_path
	with open(cfg_path, 'w') as f:
		config.write(f)

def __query(group_id, endpoint, api_key, data=None):
	api_server = config.get('client', 'api_server')
	url = '%s/v1/%s/%s' % (api_server, group_id, endpoint)
	if data is not None:
		data = json.dumps(data)
	req = urllib2.Request(url, data, {'Authorization': api_key})
	try:
		return json.load(urllib2.urlopen(req))
	except urllib2.HTTPError as e:
		sys.exit('http error (%d):\n%s' % (e.code, e.read()))
	except Exception as e:
		sys.exit('an error occurred while querying%s:\n%r' % (endpoint, e))

if len(sys.argv) > 1 and sys.argv[1] == '--configure':
	configure()
else:
	post()