Why this option not working in this Bash script?

Question

I am expanding the following function to include the option -i | --ignore-case with error-handling

#!/bin/sh
[ $# -ne 1 ] && echo "1 argument is needed" && exit 1
find $HOME -type f -name "*.tex" -exec grep -il "$1" {} + | vim -

Expanded code

#!/bin/sh
################################
# Check if parameters options  #
# are given on the commandline #
################################
while (( "$#" )); do
   case "$1" in
    -h | --help)
        echo "help menu"
        exit 0
        ;;
    -i | --ignore-case)
        [ $# -ne 2 ] && echo "1 argumenst i needed" && exit 1
        find $HOME -type f -name "*.tex" -exec grep -il "$1" {} + | vim -
        exit 0
        ;;
     -*)
        echo "Error: Unknown option: $1" >&2
        exit 1
        ;;
      *) # No more options
        break
        ;;
   esac

   shift # not sure if needed
done

# Do this if no cases chosen
[ $# -ne 1 ] && echo "1 argument is needed" && exit 1
find $HOME -type f -name "*.tex" -exec grep -l "$1" {} + | vim -

Result

1. haetex "TODO". Expected output is the same as output. Passed!
2. haetex -i "TODO". Expected result: search with ignore-case. Result: blank file.

---

Why the option -i is not working here?

Answer 1

Change the grep in the -i case to search for $2, since $1 contains the option that you just tested, not the search string.

find $HOME -type f -name "*.tex" -exec grep -il "$2" {} + | vim -

To handle multiple options, it would be better for the case statement to just set a variable, e.g.

-i | --ignore-case)
    [ $# -ne 2 ] && echo "1 argumenst i needed" && exit 1
    case_option=-i
    ;;

Then the find command after the loop would look like:

find $HOME -type f -name "*.tex" -exec grep -l $case_option "$1" {} + | vim -

In this case it can use $1 because the shift has moved the search string to the beginning of the arguments.

So the whole script looks like:

while (( "$#" )); do
   case "$1" in
    -h | --help)
        echo "help menu"
        exit 0
        ;;
    -i | --ignore-case)
        [ $# -ne 2 ] && echo "1 argumenst i needed" && exit 1
        case_option=-i
        ;;
     -*)
        echo "Error: Unknown option: $1" >&2
        exit 1
        ;;
      *) # No more options
        break
        ;;
   esac

   shift # not sure if needed
done

find $HOME -type f -name "*.tex" -exec grep -l $case_option "$1" {} + | vim -