Mvn wrapper that searches a .m2/settings.xml upwards from the current directory - if you have to use different maven installations for different projects at the same time

mvn

#!/bin/bash
# This script calls Maven with settings depending on the directory it's started.
# It searches for .m2/settings.xml in the current directory and parent directories and takes the first it finds.
# This is not done if the command line contains an argument -s or --settings.
# This is useful if you have different settings for different projects.
# In the end it expects the real mvn executable (or probably a link to it) to be named _mvn and in the PATH.

settings_file=".m2/settings.xml"
settings_dir="$(realpath .)"
use_custom_settings=true
prev_arg_is_s=false

# Check if -s or --settings is present in the command-line arguments
for arg in "$@"; do
  if $prev_arg_is_s; then
    # Skip the argument to -s or --settings
    prev_arg_is_s=false
    continue
  fi
  case "$arg" in
    -s)
      use_custom_settings=false
      prev_arg_is_s=true
      ;;
    --settings)
      use_custom_settings=false
      prev_arg_is_s=true
      ;;
    -s*)
      # Handle combined -s<settingsfile>
      use_custom_settings=false
      ;;
    --settings=*)
      # Handle --settings=<settingsfile>
      use_custom_settings=false
      ;;
  esac
done

if $use_custom_settings; then
  # Search for settings file in current and parent directories
  while true; do
    if [ "$settings_dir" = "/" ] || [ "$settings_dir" = "$HOME" ]; then
      settings_path=""
      break
    fi
    if [ -f "$settings_dir/$settings_file" ]; then
      settings_path="$settings_dir/$settings_file"
      break
    fi
    new_settings_dir="$(dirname "$settings_dir")"
    if [ "$new_settings_dir" = "$settings_dir" ]; then
      settings_path=""
      break
    fi
    settings_dir="$new_settings_dir"
  done
else
  settings_path=""
fi

if [ -n "$settings_path" ]; then
  echo "Calling mvn with -s $settings_path $*" >&2
  exec _mvn -s "$settings_path" "$@"
else
  exec _mvn "$@"
fi