#!/bin/bash

# powersw - power switch utility.
# Turn on and off the power to various external devices.
#
# This knows about two ways to control the power:
# (1) Control from a USB hub.  The hubpower program is used to actually 
# toggle the power.  This script adds a layer on top of that to find 
# the right port on the right hub.
# (2) Control from an IP Power 9258 power switch.  This script sends an 
# HTTP request to the switch to toggle the power.
#
# By Philip Endecott, 2010.
# I hearby place this code in the public domain.


usage() {
  echo "Usage: powersw [--delay <secs>] <device> [on|off]"
  echo "See /etc/powersw.conf for device configuration."
  exit 1
}

find_hub() {
  # We're looking for a hub with no devices connected to it and per-port 
  # power switching.
  hub_bus_dev=`lsusb -v | tr -d ':' |
    awk '/^Bus [0-9]+ Device [0-9]+/ { bus=$2; dev=$4; ppps=0; any_devs=0; }
         /Per-port power switching/  { ppps=1; }
         /Port.*connect/             { any_devs=1; }
         /^$/                        { if (ppps && !any_devs) exit; }
         END                         { if (ppps && !any_devs) printf("%s:%s",bus,dev); } '`
  if [ -z "${hub_bus_dev}" ]
  then
    echo "Can't find power control hub"
    exit 1
  fi
}

find_device() {
  l=`cat /etc/powersw.conf | awk '!/^#/ && !/^$/ && $1=="'$device'"'`
  if [ -z "${l}" ]
  then
    echo "Can't find requested device '${device}' in /etc/powersw.conf"
    exit 1
  fi
  controller=`echo $l | awk '{print $2}'`
  portnum=`echo $l | awk '{print $3}'`
}

do_hubpower() {
  hubpower "${hub_bus_dev}" power "${portnum}" "${action}"
}

do_powerswitch() {
  case "${action}" in
    on) state=1 ;;
    off) state=0 ;;
    *) echo "Unknown state '${state}'" ; exit 1 ;;
  esac
  url="http://admin:12345678@powerswitch/Set.cmd?CMD=SetPower+P$((59+${portnum}))=${state}"
echo $url
  wget "${url}"
}


do_switch() {
  case "${controller}" in
    usb) do_hubpower ;;
    powerswitch) do_powerswitch ;;
  esac
}  


delay=""

case $1 in
--delay) delay=$2 ; shift ; shift ;;
*) ;;
esac

case $# in
2) ;;
*) usage ;;
esac

device=$1
action=$2

case $action in
on|off) ;;
*) usage ;;
esac

find_device

case "${controller}" in
  usb) find_hub ;;
  powerswitch) ;;
  *) echo "controller '${controller}' unknown" ; exit 1 ;;
esac

if [ -z $delay ]
then
  do_switch

else
  ( sleep $delay ; do_switch ) &

fi