#!/bin/sh
# edge cases give me headache

lns () {
	# prevent `mvln file1 file1` or `mvln dir1/file1 dir1/`
	# which means `ln -s samename samename` or `ln -s dir/file dir/`
	# both $1 and $2 here are realpath
	[ "$1" != "$2" ] && ln -s -- "$1" "$2"
}

mv -i -- "$@"
# consider `mvln file1 dir/file2`
if [ $# -eq 2 ] && ! [ -d "$2" ]; then
	# use realpath here
	lns "$(realpath "$2")" "$(realpath "$1")" 	
else
	dir="$(realpath -- "$(lastarg "$@")")"
	# steal from https://unix.stackexchange.com/a/353833/459013
	while [ $# -gt 1 ]; do
		to="$(realpath -- "$1")"
		# prevent `mvln dir1/ dir1/`
		if [ "$dir" != "$to" ]; then
			lns "$dir/$(basename "$1")" "$to"
		fi
		shift
	done
fi