#!/usr/bin/env bash
#
# Add a directory to the front of the PATH if it exists and is not already there
# Usage: x-path-prepend <dir>

# Set verbosity with VERBOSE=1
VERBOSE="${VERBOSE:-0}"

# Function to print usage information
usage()
{
  echo "Usage: $0 <dir>"
  exit 1
}

# Function to print messages if VERBOSE is enabled
# $1 - message (string)
msg()
{
  [[ "$VERBOSE" -eq 1 ]] && echo "$1"
}

# Function to add a directory to the front of PATH
# $1 - directory to add (string)
prepend_to_path()
{
  local dir=$1

  if [ ! -d "$dir" ]; then
    msg "(?) Directory $dir does not exist"
    exit 0
  fi

  if echo "$PATH" | grep -qE "(^|:)$dir($|:)"; then
    msg "(!) Directory $dir is already in PATH"
  else
    export PATH="$dir${PATH:+":$PATH"}"
    msg "(!) Directory $dir has been added to the front of PATH"
  fi
}

# Main function
main()
{
  if [ "$#" -ne 1 ]; then
    usage
  fi

  prepend_to_path "$1"
}

main "$@"