#! /bin/sh

# cmd-sel -- selects the path for a given command
# $Id$
# Carlos Duarte <cgd@mail.teleweb.pt>, 981008/990419

# usage: ./cmd-sel [-m] name1 [name2 ...] [-- tests]

# usage 1 (no tests):
# 	cmd-sel mawk nawk gawk awk 
# 		just selects available awk, in order of preference
# 		(mawk first, awk last)
# 
# usage 2 (test as an hint to the best): 
# 	cmd-sel sed gsed gnused -- %% --version \| grep -i gnu
# 		selects available sed, using test as a tie breaker
# 		(altough "sed" appears first, if gsed exists and 
# 		responds something with "gnu" to "--version", this
# 		will be selected)
# 
# 		%% gets replaced with each name, when testing
# 
# usage 3 (test must be passed): 
# 	cmd-sel mawk nawk gawk awk -- %% --version \| grep -i gnu 
# 		will select awk that responds ok to given test, but
# 		will fail if none responds ok, even if any exist
# 		on path
# 	

if test "x$1" = "x-m"; then
	must_test=yes
	shift
fi

while test $# -ne 0; do 
	if test "x$1" = "x--"; then
		shift
		break; 
	fi
	n="$n $1"
	shift
done

if test $# -ne 0; then
	# has tests to do 
	for t
	do
		if test "$t" = "%%"; then 
			tst="$tst \$p/\$cmd"
		else 
			tst="$tst $t"
		fi
	done
else
	must_test=
fi

for p in `echo $PATH | tr : " "`; do 
	for cmd in $n; do 
		if test -x "$p/$cmd"; then
			test "$must_test" = "yes" || best="$p/$cmd"
			if test $# -eq 0; then
				# no tests, then this is the best
				break 2; 
			else 
				# if pass test, then is the best
				# else, remember current best, and keep 
				# searching
				eval "exec 2>&1; $tst" >/dev/null && break 2
			fi
		fi
	done
done

if test "$best" != ""; then
	echo "$best"
	exit 0; 
fi
exit 1