fixes for tool_swap script

Thanks Hr_Ravn!

extras/tool_swap/tool_swap.sh

@@ -1,19 +1,19 @@
 #!/bin/bash
 
 # Copyright (C) 2022 Chris Laprade
-# 
+#
 # This file is part of zippy_config.
-# 
+#
 # zippy_config is free software: you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by
 # the Free Software Foundation, either version 3 of the License, or
 # (at your option) any later version.
-# 
+#
 # zippy_config is distributed in the hope that it will be useful,
 # but WITHOUT ANY WARRANTY; without even the implied warranty of
 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 # GNU General Public License for more details.
-# 
+#
 # You should have received a copy of the GNU General Public License
 # along with zippy_config. If not, see <http://www.gnu.org/licenses/>.
 
@@ -22,6 +22,8 @@
 ### Written with the assistance of an AI ###
 ############################################
 
+# Define the file to be searched
+filename=~/printer_data/config/printer.cfg
 
 # Check if the required number of arguments have been provided
 if [ $# -ne 1 ]
@@ -30,22 +32,23 @@ then
  exit 1
 fi
 
-# Assign the argument to a variable
+# Assign the argument to a variable as an integer
+
 tool_number=$1
+# Convert to an inteeger
+tool_number=$((tool_number))
+
 
 # Check if the input parameter is a valid integer
-if ! [[ $tool_number =~ ^[0-9]+$ ]]
+if [ $tool_number -lt 0 ]
 then
- echo "Error: Invalid input. Integer required."
+ echo "Error: Invalid input. Integer must be greater than or equal to 0."
  exit 1
 fi
 
 # Construct the replacement string
 replace_string="[include tool$tool_number.cfg]"
 
-# Define the file to be searched
-filename=~/printer_data/config/printer.cfg
-
 # Check if the file exists
 if [ ! -f "$filename" ]
 then
@@ -69,7 +72,7 @@ else
  echo "Error: More than one occurrence of the regex pattern was found."
  exit 1
  fi
-
+ 
  mv "$temp_file" "$filename"
 fi