# Copyright 1999-2014 Gentoo Foundation
# Distributed under the terms of the GNU General Public License v2
# $Id$

# @ECLASS: mercurial.eclass
# @MAINTAINER:
# Christoph Junghans <ottxor@gentoo.org>
# Dirkjan Ochtman <djc@gentoo.org>
# @AUTHOR:
# Next gen author: Krzysztof Pawlik <nelchael@gentoo.org>
# Original author: Aron Griffis <agriffis@gentoo.org>
# @BLURB: This eclass provides generic mercurial fetching functions
# @DESCRIPTION:
# This eclass provides generic mercurial fetching functions. To fetch sources
# from mercurial repository just set EHG_REPO_URI to correct repository URI. If
# you need to share single repository between several ebuilds set EHG_PROJECT to
# project name in all of them.

inherit eutils

EXPORT_FUNCTIONS src_unpack

DEPEND="dev-vcs/mercurial"

# @ECLASS-VARIABLE: EHG_REPO_URI
# @DESCRIPTION:
# Mercurial repository URI.

# @ECLASS-VARIABLE: EHG_REVISION
# @DESCRIPTION:
# Create working directory for specified revision, defaults to default.
#
# EHG_REVISION is passed as a value for --updaterev parameter, so it can be more
# than just a revision, please consult `hg help revisions' for more details.
: ${EHG_REVISION:="default"}

# @ECLASS-VARIABLE: EHG_STORE_DIR
# @DESCRIPTION:
# Mercurial sources store directory. Users may override this in /etc/portage/make.conf
[[ -z "${EHG_STORE_DIR}" ]] && EHG_STORE_DIR="${PORTAGE_ACTUAL_DISTDIR:-${DISTDIR}}/hg-src"

# @ECLASS-VARIABLE: EHG_PROJECT
# @DESCRIPTION:
# Project name.
#
# This variable default to $PN, but can be changed to allow repository sharing
# between several ebuilds.
[[ -z "${EHG_PROJECT}" ]] && EHG_PROJECT="${PN}"

# @ECLASS-VARIABLE: EGIT_CHECKOUT_DIR
# @DESCRIPTION:
# The directory to check the hg sources out to.
#
# EHG_CHECKOUT_DIR=${S}

# @ECLASS-VARIABLE: EHG_QUIET
# @DESCRIPTION:
# Suppress some extra noise from mercurial, set it to 'ON' to be quiet.
: ${EHG_QUIET:="OFF"}
[[ "${EHG_QUIET}" == "ON" ]] && EHG_QUIET_CMD_OPT="--quiet"

# @ECLASS-VARIABLE: EHG_CLONE_CMD
# @DESCRIPTION:
# Command used to perform initial repository clone.
[[ -z "${EHG_CLONE_CMD}" ]] && EHG_CLONE_CMD="hg clone ${EHG_QUIET_CMD_OPT} --pull --noupdate"

# @ECLASS-VARIABLE: EHG_PULL_CMD
# @DESCRIPTION:
# Command used to update repository.
[[ -z "${EHG_PULL_CMD}" ]] && EHG_PULL_CMD="hg pull ${EHG_QUIET_CMD_OPT}"

# @ECLASS-VARIABLE: EHG_OFFLINE
# @DESCRIPTION:
# Set this variable to a non-empty value to disable the automatic updating of
# a mercurial source tree. This is intended to be set outside the ebuild by
# users.
EHG_OFFLINE="${EHG_OFFLINE:-${EVCS_OFFLINE}}"

# @FUNCTION: mercurial_fetch
# @USAGE: [repository_uri] [module] [sourcedir]
# @DESCRIPTION:
# Clone or update repository.
#
# If repository URI is not passed it defaults to EHG_REPO_URI, if module is
# empty it defaults to basename of EHG_REPO_URI, sourcedir defaults to 
# EHG_CHECKOUT_DIR, which defaults to S.

mercurial_fetch() {
	debug-print-function ${FUNCNAME} "${@}"

	has "${EAPI:-0}" 0 1 2 && ! use prefix && EPREFIX=

	EHG_REPO_URI=${1-${EHG_REPO_URI}}
	[[ -z "${EHG_REPO_URI}" ]] && die "EHG_REPO_URI is empty"

	local module="${2-$(basename "${EHG_REPO_URI}")}"
	local sourcedir="${3:-${EHG_CHECKOUT_DIR:-${S}}}"

	# Should be set but blank to prevent using $HOME/.hgrc
	export HGRCPATH=

	# Check ${EHG_STORE_DIR} directory:
	addwrite "$(dirname "${EHG_STORE_DIR}")" || die "addwrite failed"
	if [[ ! -d "${EHG_STORE_DIR}" ]]; then
		mkdir -p "${EHG_STORE_DIR}" || die "failed to create ${EHG_STORE_DIR}"
		chmod -f g+rw "${EHG_STORE_DIR}" || \
			die "failed to chown ${EHG_STORE_DIR}"
	fi

	# Create project directory:
	mkdir -p "${EHG_STORE_DIR}/${EHG_PROJECT}" || \
		die "failed to create ${EHG_STORE_DIR}/${EHG_PROJECT}"
	chmod -f g+rw "${EHG_STORE_DIR}/${EHG_PROJECT}" || \
		echo "Warning: failed to chmod g+rw ${EHG_PROJECT}"
	pushd "${EHG_STORE_DIR}/${EHG_PROJECT}" > /dev/null || \
		die "failed to cd to ${EHG_STORE_DIR}/${EHG_PROJECT}"

	# Clone/update repository:
	if [[ ! -d "${module}" ]]; then
		einfo "Cloning ${EHG_REPO_URI} to ${EHG_STORE_DIR}/${EHG_PROJECT}/${module}"
		${EHG_CLONE_CMD} "${EHG_REPO_URI}" "${module}" || {
			rm -rf "${module}"
			die "failed to clone ${EHG_REPO_URI}"
		}
	elif [[ -z "${EHG_OFFLINE}" ]]; then
		einfo "Updating ${EHG_STORE_DIR}/${EHG_PROJECT}/${module} from ${EHG_REPO_URI}"
		pushd "${module}" > /dev/null || die "failed to cd to ${module}"
		${EHG_PULL_CMD} "${EHG_REPO_URI}" || die "update failed"
		popd > /dev/null || die
	fi
	popd > /dev/null || die

	# Checkout working copy:
	einfo "Creating working directory in ${sourcedir} (target revision: ${EHG_REVISION})"
	mkdir -p "${sourcedir}" || die "failed to create ${sourcedir}"
	hg clone \
		${EHG_QUIET_CMD_OPT} \
		--updaterev="${EHG_REVISION}" \
		"${EHG_STORE_DIR}/${EHG_PROJECT}/${module}" \
		"${sourcedir}" || die "hg clone failed"
	# An exact revision helps a lot for testing purposes, so have some output...
	# id           num  branch
	# fd6e32d61721 6276 default
	local HG_REVDATA=($(hg identify -b -i "${sourcedir}"))
	export HG_REV_ID=${HG_REVDATA[0]}
	local HG_REV_BRANCH=${HG_REVDATA[1]}
	einfo "Work directory: ${sourcedir} global id: ${HG_REV_ID} (was ${EHG_REVISION} branch: ${HG_REV_BRANCH}"
}

# @FUNCTION: mercurial_bootstrap
# @INTERNAL
# @DESCRIPTION:
# Internal function that runs bootstrap command on unpacked source.
mercurial_bootstrap() {
	debug-print-function ${FUNCNAME} "$@"

	# @ECLASS-VARIABLE: EHG_BOOTSTRAP
	# @DESCRIPTION:
	# Command to be executed after checkout and clone of the specified
	# repository.
	if [[ ${EHG_BOOTSTRAP} ]]; then
		pushd "${S}" > /dev/null
		einfo "Starting bootstrap"

		if [[ -f ${EHG_BOOTSTRAP} ]]; then
			# we have file in the repo which we should execute
			debug-print "${FUNCNAME}: bootstraping with file \"${EHG_BOOTSTRAP}\""

			if [[ -x ${EHG_BOOTSTRAP} ]]; then
				eval "./${EHG_BOOTSTRAP}" \
					|| die "${FUNCNAME}: bootstrap script failed"
			else
				eerror "\"${EHG_BOOTSTRAP}\" is not executable."
				eerror "Report upstream, or bug ebuild maintainer to remove bootstrap command."
				die "\"${EHG_BOOTSTRAP}\" is not executable"
			fi
		else
			# we execute some system command
			debug-print "${FUNCNAME}: bootstraping with commands \"${EHG_BOOTSTRAP}\""

			eval "${EHG_BOOTSTRAP}" \
				|| die "${FUNCNAME}: bootstrap commands failed"
		fi

		einfo "Bootstrap finished"
		popd > /dev/null
	fi
}

# @FUNCTION: mercurial_src_unpack
# @DESCRIPTION:
# The mercurial src_unpack function, which will be exported.
function mercurial_src_unpack {
	debug-print-function ${FUNCNAME} "$@"

	mercurial_fetch
	mercurial_bootstrap
}