# pylint: disable=C0111,R0903

"""Periodically checks the RTT of a configurable host using ICMP echos

Requires the following executable:
    * ping

Parameters:
    * ping.interval: Time in seconds between two RTT checks (defaults to 60)
    * ping.address : IP address to check
    * ping.timeout : Timeout for waiting for a reply (defaults to 5.0)
    * ping.probes  : Number of probes to send (defaults to 5)
    * ping.warning : Threshold for warning state, in seconds (defaults to 1.0)
    * ping.critical: Threshold for critical state, in seconds (defaults to 2.0)
"""

import re
import time
import threading

import bumblebee.input
import bumblebee.output
import bumblebee.engine

def get_rtt(module, widget):
    try:
        widget.set('rtt-unreachable', False)
        res = bumblebee.util.execute('ping -n -q -c {} -W {} {}'.format(
            widget.get('rtt-probes'), widget.get('rtt-timeout'), widget.get('address')
        ))

        for line in res.split('\n'):
            if line.startswith('{} packets transmitted'.format(widget.get('rtt-probes'))):
                m = re.search(r'(\d+)% packet loss', line)

                widget.set('packet-loss', m.group(1))

            if not line.startswith('rtt'): continue
            m = re.search(r'([0-9\.]+)/([0-9\.]+)/([0-9\.]+)/([0-9\.]+)\s+(\S+)', line)

            widget.set('rtt-min', float(m.group(1)))
            widget.set('rtt-avg', float(m.group(2)))
            widget.set('rtt-max', float(m.group(3)))
            widget.set('rtt-unit', m.group(5))
    except Exception as e:
        widget.set('rtt-unreachable', True)

class Module(bumblebee.engine.Module):
    def __init__(self, engine, config):
        widget = bumblebee.output.Widget(full_text=self.rtt)
        super(Module, self).__init__(engine, config, widget)

        widget.set('address', self.parameter('address', '8.8.8.8'))
        widget.set('interval', self.parameter('interval', 60))
        widget.set('rtt-probes', self.parameter('probes', 5))
        widget.set('rtt-timeout', self.parameter('timeout', 5.0))
        widget.set('rtt-avg', 0.0)
        widget.set('rtt-unit', '')
        widget.set('packet-loss', 0)

        self._next_check = 0

    def rtt(self, widget):
        if widget.get('rtt-unreachable'):
            return '{}: unreachable'.format(widget.get('address'))
        return '{}: {:.1f}{} ({}%)'.format(
            widget.get('address'),
            widget.get('rtt-avg'),
            widget.get('rtt-unit'),
            widget.get('packet-loss')
        )

    def state(self, widget):
        if widget.get('rtt-unreachable'): return ['critical']
        return self.threshold_state(widget.get('rtt-avg'), 1000.0, 2000.0)

    def update(self, widgets):
        if int(time.time()) < self._next_check:
            return
        thread = threading.Thread(target=get_rtt, args=(self, widgets[0],))
        thread.start()
        self._next_check = int(time.time()) + int(widgets[0].get('interval'))

# vim: tabstop=8 expandtab shiftwidth=4 softtabstop=4