# Copyright 1999-2003 Gentoo Technologies, Inc.
# Distributed under the terms of the GNU General Public License v2
# $Header$
#
# Author: Andres Loeh <kosmikus@gentoo.org>
#
# This eclass helps with the Glasgow Haskell Compiler's package
# configuration utility.

ECLASS=haskell
INHERITED="$INHERITED $ECLASS"

PATH="${PATH}:/opt/ghc/bin"

# for later configuration using environment variables
ghc-getghc() {
	echo "ghc"
}

ghc-getghcpkg() {
	echo "ghc-pkg"
}

ghc-getghcpkgbin() {
	echo $(ghc-libdir)/"ghc-pkg.bin"
}

# returns the version
ghc-version() {
	$(ghc-getghc) --version | sed 's:^.*version ::'
}

# returns the library directory
ghc-libdir() {
	$(ghc-getghc) --print-libdir
}

# returns the (Gentoo) library configuration directory
ghc-confdir() {
	echo $(ghc-libdir)/gentoo
}

# returns the name of the local (package-specific)
# package configuration file
ghc-localpkgconf() {
	echo "${PF}.conf"
}

# creates an empty local (package-specific) package
# configuration file
ghc-setup-pkg() {
	echo '[]' > ${S}/$(ghc-localpkgconf)
}

# moves the local (package-specific) package configuration
# file to its final destination
ghc-install-pkg() {
	mkdir -p ${D}/$(ghc-confdir)
	cat ${S}/$(ghc-localpkgconf) | sed "s:${D}::" \
		> ${D}/$(ghc-confdir)/$(ghc-localpkgconf)
}

# registers all packages in the local (package-specific)
# package configuration file
ghc-register-pkg() {
	local localpkgconf
	localpkgconf=$(ghc-confdir)/$1
	for pkg in $(ghc-listpkg ${localpkgconf}); do
		einfo "Registering ${pkg} ..."
		$(ghc-getghcpkgbin) -f ${localpkgconf} -s ${pkg} \
			| $(ghc-getghcpkg) -u --auto-ghci-libs --force
	done
}

# re-adds all available .conf files to the global
# package conf file
ghc-reregister() {
	einfo "Re-adding packages ..."
	ewarn "This may cause several warnings, but they should be harmless."
	pushd $(ghc-confdir)
	for conf in *.conf; do
		einfo "Processing ${conf} ..."
		ghc-register-pkg ${conf}
	done
	popd
}

# unregisters ...
ghc-unregister-pkg() {
	local localpkgconf
	localpkgconf=$(ghc-confdir)/$1
	for pkg in $(ghc-reverse "$(ghc-listpkg ${localpkgconf})"); do
		einfo "Unregistering ${pkg} ..."
		$(ghc-getghcpkg) -r ${pkg} --force
	done
}

# help-function: reverse a list
ghc-reverse() {
	local result
	for i in $1; do
		result="${i} ${result}"
	done
	echo ${result}
}

ghc-listpkg() {
	echo $($(ghc-getghcpkgbin) -l -f $1) \
		| cut -f2 -d':' \
		| cut -f1 -d'/' \
		| sed 's:,: :g'
} 

haskell_pkg_postinst() {
	ghc-register-pkg $(ghc-localpkgconf)
}

haskell_pkg_prerm() {
	# only remove if this is the only instance of the package on the
	# system ...
        has_version "<${CATEGORY}/${PF}" || has_version ">${CATEGORY}/${PF}" \
		|| ghc-unregister-pkg $(ghc-localpkgconf)
}

EXPORT_FUNCTIONS pkg_postinst pkg_prerm