# Elgato from the shell

Once the lamp joined my local WLAN network (and I know the IP address), I use this script for controlling it.

## Requirements

* You must have `cURL` and `jq` installed. (`sudo apt-get install jq curl`)
* The script sets a local `ELGATO_KEY_LIGHT_IPADDRESS` variable. Tweak that part to your needs.

## Manual

* `e` turns it on or off
* Brightness
  * `e +` increases the brightness
  * `e -` decreases the brightness
* Color tempreature
  * `e 1` selects the coldest color temperature
  * `e 2` selects a medium color temperature
  * `e 3` selects the warmest color temperature
* Identify the light
  * `e i` makes the light blink three times

## Contents of `/usr/local/bin/e`

```bash
#!/bin/bash

function _elgatoGet {
  local ip="$1"
  local path="$2"

  curl --silent \
      --url "http://${ip}:9123/elgato/${path}"
}

function _elgatoPut {
  local ip="$1"
  local path="$2"
  local msg="$3"

  echo "${msg}" | curl --silent --request PUT \
      --header "Content-Type: application/json" \
      --url "http://${ip}:9123/elgato/${path}" \
      --data @-
}

function _elgatoIdentify {
  local ip="$1"

  local displayName="$( _elgatoGet "${ip}" "accessory-info" | jq -r ".displayName" )"

  echo "Light ${displayName} is blinking"

  # empty POST
  curl --silent \
    --request POST\
    --url "http://${ip}:9123/elgato/identify"
}

function _elgatoTurnOnOff {
  local ip="$1"
	local current="$( _elgatoGet "${ip}" "lights" | jq ".lights[0].on" )"
	local new="$(( 1-${current} ))"
	local state="$( _elgatoPut "${ip}" "lights" "{ \"lights\" : [ { \"on\" : ${new} } ] }" | jq ".lights[0].on" )"
  local displayName="$( _elgatoGet "${ip}" "accessory-info" | jq -r ".displayName" )"

  echo "$( if [[ "${state}" == "0" ]] ; then echo "Light \"${displayName}\" turned off" ; else echo "Light \"${displayName}\" turned on" ; fi ; )"
}

function _elgatoTemperature {
  local ip="$1"
  local temperature="$2"

  # temperature must be in range [143..344]
  if [[ ${temperature} -lt 143 ]] ; then 
    temperature="143" ;
  elif [[ ${temperature} -gt 344 ]] ; then 
    temperature="344" ;
  fi
  
  echo "Temperature: $( _elgatoPut "${ip}" lights \
    "{\"lights\":[{ \"on\": 1 , \"temperature\": ${temperature} }]}" \
    | jq '.lights[0].temperature' )"
}

function _elgatoBrightness {
  local ip="$1"
  local brightnessDelta="$2"

  local currentBrightness="$( _elgatoGet "${ip}" lights | jq ".lights[0].brightness" )"
  local newBrightness="$(( $currentBrightness + $brightnessDelta ))"

  # brightness must be in range [3..100]
  if [[ ${newBrightness} -lt 3 ]] ; then 
    newBrightness="3" ;
  elif [[ ${newBrightness} -gt 100 ]] ; then 
    newBrightness="100" ;
  fi
  
  echo "Brightness: $( _elgatoPut "${ip}" lights \
    "{\"lights\":[{ \"on\": 1 , \"brightness\": ${newBrightness} }]}" \
    | jq '.lights[0].brightness' )"
}

# ELGATO_KEY_LIGHT_IPADDRESS="192.168.0.106"
ELGATO_KEY_LIGHT_IPADDRESS="elgatoip"

if [[ $# -eq 0 ]] ; then 
  echo "$( _elgatoTurnOnOff  "${ELGATO_KEY_LIGHT_IPADDRESS}" )"
elif [[ $# -eq 1 ]] ; then
  command=$1
  if [[ "${command}" == "+" ]] ; then
    echo "$( _elgatoBrightness  "${ELGATO_KEY_LIGHT_IPADDRESS}" 20 )"
  elif [[ "${command}" == "-" ]] ; then
    echo "$( _elgatoBrightness  "${ELGATO_KEY_LIGHT_IPADDRESS}" -20 )"
  elif [[ "${command}" == "1" ]] ; then
    echo "$( _elgatoTemperature "${ELGATO_KEY_LIGHT_IPADDRESS}" 143 )"
  elif [[ "${command}" == "2" ]] ; then
    echo "$( _elgatoTemperature "${ELGATO_KEY_LIGHT_IPADDRESS}" 243 )"
  elif [[ "${command}" == "3" ]] ; then
    echo "$( _elgatoTemperature "${ELGATO_KEY_LIGHT_IPADDRESS}" 344 )"
  elif [[ "${command}" == "i" ]] ; then
    echo "$( _elgatoIdentify "${ELGATO_KEY_LIGHT_IPADDRESS}" )"
  fi
fi
```


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