shell: add rm-prefer-trash script

.config/shell/bin/rm-prefer-trash

@@ -0,0 +1,170 @@
+#!/bin/sh
+# cause plain rm wasn't good enough
+# auto selects what trash directory to put files in if rmtrash is available
+# otherwise, uses rm
+
+set -eu
+
+rm='rm'
+
+err_differing_filesystems() {
+   echo 'Error: some files are apart of different filesystems.' >&2
+   # shellcheck disable=SC2016
+   echo 'Either set RM=rm to force not using `trash`, or remove the files individually' >&2
+}
+
+fs(){
+   df "$1" | sed '1d' | cut -d ' ' -f 1
+}
+
+dbg() {
+   echo "$@" >&2
+}
+
+rm_warning() {
+   echo 'WARNING: using rm - NOT trash. Files will be PERMINANTLY DELETED!' >&2
+   printf '%s'  "Type Y to continue: " >&2
+   read -r confirm
+   if [ "$confirm" != 'Y' ]; then
+      printf '\n'
+      exit 1
+   fi
+   echo 'Waiting 3 seconds before continuing.' >&2
+   sleep 3
+}
+
+rm_custom_warning() {
+   echo 'WARNING: using custom rm command: '"$rm" >&2
+   echo 'This might NOT use the trash'
+   echo ''
+   echo 'Waiting 5 seconds before continuing.' >&2
+   sleep 5
+}
+
+err_no_trashdirs() {
+   echo 'Error: No trash directorys with matching filesystems are available.' >&2
+   echo 'Please set TRASH_DIRS to a colon-separated list of your preferred trash directories.' >&2
+}
+
+usage() {
+   echo "Wrapper for rm and rm-trash commands"
+   echo ""
+   echo "Environment:"
+   echo " RM          Force using a particular rm command."
+   # shellcheck disable=SC2016
+   echo ' TRASH_DIRS  What directories to use as trash locations for `trash`.'
+   echo ' DRY         Dry run: print the rm command instead of executing it.'
+   echo ""
+   echo "Usage:"
+   echo " ${0##*/} [ARGS]"
+   echo ""
+   echo "Where ARGS is the argument list corresponding to the rm command to be used."
+   echo ""
+   echo "Current selection for rm command: $which_rm"
+}
+
+do_rm() {
+   if [ "${DRY:-false}" = true ]; then
+      echo "$rm" "$@"
+   else
+      "$rm" "$@"
+   fi
+}
+
+do_rmnormal() {
+   # shellcheck disable=SC2209
+   rm=rm
+   rm_warning
+   do_rm "$@"
+}
+
+do_rmcustom() {
+   # check if we have been given an rm command
+   rm="$RM"
+   rm_custom_warning
+   do_rm "$@"
+}
+
+do_rmtrash() {
+   # get trash directories
+   trash_default_fallback="$HOME"/.local/share
+   trash_default="${XDG_DATA_HOME:-"$trash_default_fallback"}/Trash"
+   trashdirs="${TRASH_DIRS:-"$trash_default"}"
+
+   # if trash is available, use it
+   rm='trash'
+   fs1=''
+   # validate that all files are on the same filesystem
+   for a; do
+      if [ -e "$a" ]; then
+         fs="$(fs "$a")"
+         if [ -z "$fs1" ]; then
+            fs1="$fs"
+            # this will only run the first time through the loop
+            continue
+         fi
+         # ensure all files are on the same filesystem
+         if [ "$fs1" != "$fs" ]; then
+            err_differing_filesystems
+            exit 1
+         fi
+      fi
+   done
+   if [ "$fs1" != '' ]; then
+      # if we get here, we have validated that all the files are on the same filesystem
+      trashdir=''
+      found_trash=false
+      while [ "$trashdirs" != "$trashdir" ]; do
+         trashdir="${trashdirs%%:*}"
+         trashdirs="${trashdirs#"$trashdir":}"
+         fs="$(fs "$trashdir")"
+         if [ "$fs" = "$fs1" ]; then
+            found_trash=true
+            break
+         fi
+      done
+      if [ "$found_trash" = true ]; then
+         set -- --trash-dir "$trashdir" "$@"
+      else
+         err_no_trashdirs
+         exit 1
+      fi
+   fi
+   echo "trash dir:" "$trashdir"
+   do_rm "$@"
+}
+
+main() {
+   # which rm command to use
+   rm=''
+
+   # calculate which rm command to use
+   which_rm=''
+   if [ -n "${RM:-}" ]; then
+      which_rm='custom: '"$RM"
+   elif command -v trash > /dev/null; then
+      which_rm='trash'
+   else
+      which_rm='rm'
+   fi
+
+   # print usage information (including which rm command we'll use)
+   if [ $# = 0 ]; then
+      usage
+      exit
+   fi
+
+   # execute rm
+   case "$which_rm" in
+      rm)
+         do_rmnormal "$@";;
+      trash)
+         do_rmtrash "$@";;
+      custom*)
+         do_rmcustom "$@";;
+      *)
+         usage; exit;;
+   esac
+}
+
+main "$@"