# Copyright 1999-2010 Gentoo Foundation
# Distributed under the terms of the GNU General Public License v2
# $Header: $

#
# Author: Hanno Meyer-Thurow
# Purpose: Serve paths to boost libraries & headers
#

inherit flag-o-matic multilib

# add_boost_library_path
#
# one paramater: boost version
#
# ex: add_boost_library_path 1_42
add_boost_library_path() {
	local path="$(check_boost_library_path ${*})"

	if [ "${path}" ] ; then
		append-ldflags "-L${path}"
	else
		die "path not found!"
	fi
}

# add_boost_include_path
#
# one paramater: boost version
#
# ex: add_boost_include_path 1_42
add_boost_include_path() {
	local path="$(check_boost_include_path ${*})"

	if [ "${path}" ] ; then
		append-cxxflags "-I${path}"
	else
		die "path not found!"
	fi
}

# add_boost_paths: convenient wrapper
#
# one parameter optionally: boost version
#
# ex: add_boost_paths
# ex: add_boost_paths 139
# ex: add_boost_paths =139
# ex: add_boost_paths <139
# ex: add_boost_paths >139
add_boost_paths() {
	# required for analyse
	local BV

	# analyse
	_boost_analyse ${*}

	add_boost_include_path ${BV}
	add_boost_library_path ${BV}
}

# check_boost_library_path
#
# one paramater: boost version
#
# return value: library path to boost version
#
# ex: check_boost_library_path 1_42
check_boost_library_path() {
	[[ ${#} -eq 1 ]] || die "pass only one paramater!"

	local path="/usr/$(get_libdir)/boost-${1}"

	[ -d "${path}" ] && echo -n "${path}"
}

# check_boost_include_path
#
# one paramater: boost version
#
# return value: include path to boost version
#
# ex: check_boost_include_path 1_42
check_boost_include_path() {
	[[ ${#} -eq 1 ]] || die "pass only one paramater!"

	local path="/usr/include/boost-${1}"

	[ -d "${path}" ] && echo -n "${path}"
}

# check_boost_paths: convenient wrapper
#
# one parameter optionally: boost version
#
# ex: check_boost_paths
# ex: check_boost_paths 139
# ex: check_boost_paths =139
# ex: check_boost_paths <139
# ex: check_boost_paths >139
check_boost_paths() {
	# required for analyse
	local BV

	# analyse
	_boost_analyse ${*}

	# check include path
	check_boost_include_path ${BV} >/dev/null
	[[ ${?} -eq 0 ]] || die "include path to boost version ${BV} not found!"

	# check library path
	check_boost_library_path ${BV} >/dev/null
	[[ ${?} -eq 0 ]] || die "library path to boost version ${BV} not found!"
}

# helper functions

# return value is written to "global" variable 'BV'!
_boost_analyse() {
	# type to compare
	local type=

	# boost version
	local boost_version=0
	local final_version=0

	[[ ${#} -gt 1 ]] && die "too many parameters given!"

	# analyse paramter
	if [[ ${#} -eq 1 ]] ; then
		if [[ ${#1} == 3 ]] ; then
			type='>'

			# this even converts characters to integer value
			# - guess the results then ;)
			(( boost_version = ${1} ))
		elif [[ ${#1} == 4 ]] ; then
			type=${1:0:1}

			(( boost_version = ${1:1} ))
		else
			die "bad parameter given!"
		fi
	fi

	for b in $(ls -d -1 /usr/include/boost-*) ; do
		# version
		local version="${b: -4:4}"

		# strip underscore
		local stripversion="${version/_}"

		# test
		local found=
		[[ ${type} == '>' ]] && found="$(_boost_gt ${stripversion} ${boost_version})"
		[[ ${type} == '=' ]] && found="$(_boost_eq ${stripversion} ${boost_version})"
		[[ ${type} == '<' ]] && found="$(_boost_lt ${stripversion} ${boost_version})"

		if [ "${found}" ] ; then
			boost_version=${stripversion}
			final_version=${version}
		fi
	done

	[[ ${boost_version} -eq 0 ]] && die "no boost found!"

	einfo "found boost version ${final_version}"

	# write return value into "global" variable
	BV="${final_version}"
}

_boost_gt() {
	[[ ${1} -gt ${2} ]] \
		&& echo -n 1 \
		|| echo -n 0
}

_boost_eq() {
	[[ ${1} -eq ${2} ]] \
		&& echo -n 1 \
		|| echo -n 0
}

_boost_lt() {
	[[ ${1} -lt ${2} ]] \
		&& echo -n 1 \
		|| echo -n 0
}