blinky/scripts/blinky-feed.sh

#!/usr/bin/env bash

# author:	Daniel Sommer <daniel.sommer@velvettear.de>
# license: 	MIT

# blinky 
blinky_url="${BLINKY_URL:-localhost:3000}"
blinky_type="${BLINKY_TYPE:-morph}"
blinky_duration="${BLINKY_DURATON:-2500}"
blinky_mode="${BLINKY_MODE:-$1}"

# temperature
temperature_high="${BLINKY_TEMPERATURE_HIGH:-85000}"
temperature_critical="${BLINKY_TEMPERATURE_CRITICAL:-90000}"
threshold_upper="${BLINKY_THRESHOLD_UPPER:-66}"
threshold_lower="${BLINKY_THRESHOLD_LOWER:-33}"
thermal_zones=(
    "0"
    "1"
    "2"
    "3"
)

#############
# functions #
#############
# check for root permissions
function checkRoot() {
    [[ "$EUID" != 0 ]] && printf "error: permission denied!\n" && exit 1
}

# convert a temperature value to a rgb color value
function temperatureToRGB() {
    [[ ! "$1" ]] && printf "error: did not receive a temperature value to convert to a rgb value\n" && exit 1
    printf "converting temperature to rgb value... "
    percentage="$(bc <<< "$1 / ( $temperature_high / 100 )")"
    [[ "$percentage" -gt "100" ]] && percentage="100"
    color_main="$(bc <<< "$percentage * 2.55")"
    color_supplement="$(bc <<< "255 - $color_main")"
    color_unused="0"
    if [[ "$percentage" -ge "$threshold_upper" ]]; then
        result="$color_main, $color_supplement, $color_unused"
    elif [[ "$percentage" -ge "33" ]]; then 
        result="$color_supplement, $color_main, $color_unused"
    else 
        result="$color_unused, $color_supplement, $color_main"
    fi 
    printf "result: '$result'\n"
}

# send http post request to blinky
function sendPOST() {
    [[ ! "$1" ]] && printf "error: did not receive any arguments for post request\n" && exit 1  
	cmd="curl -X POST" 
	for arg in "$@"; do
		cmd="$cmd -d \"$arg\""
	done
	cmd="$cmd \"$blinky_url\" -s"
	printf "sending post request '$cmd'...\n"
	eval "$cmd"
}

# get (average) temperature from defined thermal zones
function getTemperature() {
	counter="0"
    printf "getting temperature value from thermal zone(s) "
	for zone in "${thermal_zones[@]}"; do
        printf "'"$zone"'... "
        for value in $(cat "/sys/devices/virtual/thermal/thermal_zone"$zone"/temp"); do
            [[ ! "$temp" ]] && temp="$value" || temp=$(( $temp + $value ))
            (( counter++ ))
        done
    done
    result="$(( $temp / $counter ))"
    printf "result: '$result'\n"
    [[ "$result" -ge "$temperature_critical" ]] && printf "warning: critical temperature reached\n" && blinky_type="pulse" && blinky_duration="500" && return 0
    [[ "$result" -ge "$temperature_high" ]] && printf "warning: maximum temperature reached\n" && blinky_type="pulse" && blinky_duration="1500" && return 0
}


#############
# main part #
#############
argument_count="$#"
index=1
while [[ "$index" -lt $(( $argument_count -1 )) ]]; do
    argument="${@: $index: 1}"
    argument="${argument,,}"
    (( index++ ))
    printf "checking arg $argument\n"
    case "$argument" in 
	-u|--url|--blinky-url)
	    blinky_url="${@: $index: 1}"
	    ;;
	-t|--type|--blinky-type)
            blinky_type="${@: $index: 1}"
            ;;
        -d|--duration|--blinky-duration)
            blinky_duration="${@: $index: 1}"
            ;;
        -m|--mode|--blinky-mode)
            blinky_mode="${@: $index: 1}"
            ;;
     esac
done

case "$blinky_mode" in
	t|temp|temperature)
        checkRoot
		getTemperature
		temperatureToRGB "$result"
		sendPOST "color=$result" "mode=$blinky_type" "duration=$blinky_duration"
		;;
	*)
        sendPOST "color=random" "mode=$blinky_type" "duration=$blinky_duration"
		;;
esac