#!/bin/bash

if [[ x$(qlist -IC app-portage/portage-utils)x == xx || \
	x$(qlist -IC app-portage/gentoolkit)x == xx ]] ; then
	echo "This utility requires both app-portage/portage-utils" >&2
	echo "and app-portage/gentoolkit.  Emerge them both and try again." >&2
	exit 1
fi

declare -a arguments atoms

arguments=( )
atoms=( )

verbose=yes
redic=no

for arg in "$@" ; do
	case $arg in
		-q|--quiet) verbose=no ;;
		-r|--redic) redic=yes ;; 
		 *) arguments=( "${arguments[@]}" "$arg" ) ;;
	esac
done

[[ ${#arguments[*]} == 0 ]] && arguments=( '@world' )

for arg in "${arguments[@]}" ; do
	if [[ ${arg} == @* ]] ; then
		newatoms=( "${arg}" )
	else
		newatoms=( "$( qlist -eICv "${arg}" | sed 's/^/=/' )" )
	fi
	newatoms=( $( dumpworld "${newatoms[@]}" ) )
	result=$?
	[[ ${result} != 0 ]] && { echo "dumpworld failed, giving up." >&2 ; exit ${result} ; }
	atoms=( "${atoms[@]}" "${newatoms[@]}" )
done

# OK, we have all the packages -- remove dups, there could be a bunch.
atoms=( $( for atom in "${atoms[@]}" ; do echo "${atom}" ; done | sort -u ) )
		
[[ ${verbose} == yes ]] && \
	echo "Checking for files depended upon by the specified atom(s):" >&2 && \
	echo >&2

total=0
totalfilechars=0
for atom in "${atoms[@]}" ; do
	# turns out equery filse includes certain files (/usr/lib/debug... but why?)
	# that qlist excludes so ... we'd might as well get all the bad news possible
	files=$( equery -Cq files "${atom}" )
	result=$?
	[[ $result == 0 ]] || { echo "equery -Cq files ${atom} failed." >&2 ; exit $result ; }
	count=$( echo "${files}" | wc -l )
	(( total += count ))
	while read filename ; do
		(( totalfilechars += ${#filename} ))
	done < <( echo "${files}" )
	if [[ ${verbose} == yes ]] ; then
		if [[ ${redic} == yes ]] ; then
			echo "${files}"
		else
			echo "${atom}: ${count}" >&2
		fi
	fi
done
[[ ${verbose} == yes ]] && echo >&2 && echo >&2

[[ ${verbose} == yes ]] && echo -n "TOTAL: "
echo -n "${total}"

averagepathlen=$(( totalfilechars / ${total} ))
[[ ${verbose} == yes ]] && echo -n " files (in ${#atoms[*]} ebuilds, average path length: ${averagepathlen})"
echo
echo

exit 0