WIP hostname coloring based on OS

gwy_prompt_host_color.zsh

#!/usr/bin/env zsh

# Copyright 2019 Gavin Weifert-Yeh
#
# Copying and distribution of this file, with or without modification,
# are permitted in any medium without royalty provided the copyright
# notice and this notice are preserved.  This file is offered as-is,
# without any warranty. 

gwy_prompt_host_color() {

local os_for_prompt
local kernel_name

kernel_name=$(uname -s)
case "$kernel_name" in
('Linux')
  # Gets from os-release file if present. File is present on all systemd OSes.
  if [[ -f /etc/os-release ]]; then os_for_prompt=$(cat /etc/os-release \
    | grep '^ID=' \
    | cut -c 4- | most)
  else os_for_prompt='Linux'
  fi
  ;;
('Darwin')
  os_for_prompt='Darwin'
  ;;
('*BSD')
  if [[ "$kernel_name" == 'FreeBSD' ]]; then
    os_for_prompt='FreeBSD'
  elif [[ "$kernel_name" == 'NetBSD' ]]; then
    os_for_prompt='NetBSD'
  elif [[ "$kernel_name" == 'OpenBSD' ]]; then
    os_for_prompt='OpenBSD'
  else
    os_for_prompt='unknown_BSD'
  fi
  ;;
('DragonFly')
  os_for_prompt='DragonFly'
  ;;
('CYGWIN')
  os_for_prompt='CYGWIN'
  ;;
(*)
  os_for_prompt='unknown'
  ;;
esac

case "$os_for_prompt" in
('arch')
  echo $'%{\e[38;2;23;147;209m%}'
  ;;
('centos')
  echo $'%{\e[38;2;164;70;143m%}'
  ;;
('CYGWIN')
  echo $'%{\e[38;2;222;0;0m%}'
  ;;
('Darwin')
  echo $'%{\e[38;2;99;99;99m%}'
  ;;
('DragonFly')
  echo $'%{\e[38;2;179;211;69m%}'
  ;;
('debian')
  echo $'%{\e[38;2;199;0;54m%}'
  ;;
('fedora')
  echo $'%{\e[38;2;41;65;114m%}'
  ;;
('FreeBSD')
  echo $'%{\e[38;2;239;0;0m%}'
  ;;
('gentoo')
  echo $'%{\e[38;2;203;199;255m%}'
  ;;
('Linux')
  echo $'%{\e[38;2;252;198;36m%}'
  ;;
('linuxmint')
  echo $'%{\e[38;2;191;255;128m%}'
  ;;
('NetBSD')
  echo $'%{\e[38;2;242;103;17m%}'
  ;;
('other_BSD')
  echo $'%{\e[38;2;190;0;0m%}'
  ;;
('puppy')
  echo $'%{\e[38;2;205;205;205m%}'
  ;;
('rhel')
  echo $'%{\e[38;2;238;0;0m%}'
  ;;
('slackware')
  echo $'%{\e[38;2;115;0;0m%}'
  ;;
('SunOS') # Includes Solaris.
  echo $'%{\e[38;2;85;131;163m%}'
 ;;
('ubuntu')
  echo $'%{\e[38;2;233;84;32m%}'
  ;;
('WSL') # Windows Subsystem for Linux
  echo $'%{\e[38;2;0;103;184m%}'
  ;;
esac
}