Automatically set background color in iTerm depending on ssh host

ssh-host-color

#!/bin/bash
#
# ssh into a machine and automatically set the background
# color of Mac OS X Terminal depending on the hostname.
#
# Installation:
# 1. Save this script to /usr/local/bin/ssh-host-color
# 2. chmod 755 /usr/local/bin/ssh-host-color
# 3. alias ssh=/usr/local/bin/ssh-host-color
# 4. export PRODUCTION_HOST="<hostname_production_server>"
# 5. Configure your host colors below.
#
# Taken from http://talkfast.org/2011/01/10/ssh-host-color
#
 
set_term_bgcolor(){
  local R=$1
  local G=$2
  local B=$3
  /usr/bin/osascript <<EOF
tell application "iTerm"
  tell the current terminal
    tell the current session
      set background color to {$(($R*65535/255)), $(($G*65535/255)), $(($B*65535/255))}
    end tell
  end tell
end tell
EOF
}

if [[ "$@" =~ "$PRODUCTION_HOST" ]]; then
  set_term_bgcolor 50 0 0
else
  set_term_bgcolor 0 40 0
fi

ssh $@
 
set_term_bgcolor 0 0 0
clear

Probably easier to use their escape codes: https://iterm2.com/documentation-escape-codes.html

changing terminal to window fixes the script to work (as of May 2024)

set_term_bgcolor(){
  local R=$1
  local G=$2
  local B=$3
  /usr/bin/osascript <<EOF
tell application "iTerm"
  tell the current window
    tell the current session
      set background color to {$(($R*65535/255)), $(($G*65535/255)), $(($B*65535/255))}
    end tell
  end tell
end tell
EOF
}

FWIW, I added the above function to my initial script and I run the function manually to set the background color.

Reference to iTerm applescript support - https://iterm2.com/documentation-scripting.html

Added some predefined colors from the Tailwind palette - https://tailwindcolor.com/

function setbg(){
  local R=$1
  local G=$2
  local B=$3
  [ -z "$1" ] && { echo "Colors: red, orange, amber, yellow, lime, green, cyan, sky, indigo, purple, pink, grey"; return; }
  [ "$1" = "red" ]    && { R=254 G=226 B=226; }
  [ "$1" = "orange" ] && { R=255 G=237 B=213; }
  [ "$1" = "amber" ]  && { R=254 G=243 B=199; }
  [ "$1" = "yellow" ] && { R=254 G=249 B=195; }
  [ "$1" = "lime" ]   && { R=236 G=252 B=203; }
  [ "$1" = "green" ]  && { R=220 G=252 B=231; }
  [ "$1" = "cyan" ]   && { R=207 G=250 B=254; }
  [ "$1" = "sky" ]    && { R=224 G=242 B=254; }
  [ "$1" = "indigo" ] && { R=224 G=231 B=255; }
  [ "$1" = "purple" ] && { R=243 G=232 B=255; }
  [ "$1" = "pink" ]   && { R=252 G=231 B=243; }
  [ "$1" = "gray" ]   && { R=243 G=244 B=246; }
  # echo "Setting to ($R, $G, $B)"
  /usr/bin/osascript <<EOF
tell application "iTerm"
  tell the current window
    tell the current session
      set background color to {$(($R*65535/255)), $(($G*65535/255)), $(($B*65535/255))}
    end tell
  end tell
end tell
EOF
}