changexseltextcase

#!/usr/bin/env bash
# 
# File:
#   changexseltextcase
# 
# Description:
#   Change the case of the selected text.
# 
# Usage:
#   changexseltextcase (--upper | --lower)
# 
# Notes:
#   This utility should be used with a keybinding or in a script.
# 
#   If the text is not being converted, increase the usleep time in the xte
#   command.
# 

case "${1}" in
  '--upper'|'--lower')
    readonly MODE="${1}"
    ;;
  *)
    # output errors as a desktop notification since this script is meant to be
    # used with a keybinding and errors printed to stderr will not be seen.
    msg='Mode not specified or invalid; must use option\n--upper or --lower'
    notify-send 'changecase (err)' "${msg}"
    exit 1
    ;;
esac

readonly PREV_CLIPBOARD_CONTENT="$(xclip -o -selection c)"

# use "xclip -out -selection primary" instead of "xsel" as it causes the
# selected text to be unselected in some applications.
readonly SEL_TEXT="$(xclip -out -selection primary)"

if [ "${MODE}" = '--upper' ]; then
  chngdCase="$(echo -n "${SEL_TEXT}" | tr '[:lower:]' '[:upper:]')"
else
  chngdCase="$(echo -n "${SEL_TEXT}" | tr '[:upper:]' '[:lower:]')"
fi

echo -n "${chngdCase}" | xclip -selection c
xte 'usleep 200000' 'keydown Control_L' 'key v' 'keyup Control_L'

# Must sleep before restoring the clipboard content because otherwise the
# keyevents will run after, causing it to get pasted instead.
(sleep .1 && echo -n "${PREV_CLIPBOARD_CONTENT}" | xclip -selection c) &