#
# CDDL HEADER START
#
# The contents of this file are subject to the terms of the
# Common Development and Distribution License (the "License").
# You may not use this file except in compliance with the License.
#
# You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
# or http://www.opensolaris.org/os/licensing.
# See the License for the specific language governing permissions
# and limitations under the License.
#
# When distributing Covered Code, include this CDDL HEADER in each
# file and include the License file at usr/src/OPENSOLARIS.LICENSE.
# If applicable, add the following below this CDDL HEADER, with the
# fields enclosed by brackets "[]" replaced with your own identifying
# information: Portions Copyright [yyyy] [name of copyright owner]
#
# CDDL HEADER END
#

#
# Copyright (c) 2010, 2016, Oracle and/or its affiliates. All rights reserved.
#

GIT =		/usr/bin/git

#
# Anything that we pull from a GIT repo must have a GIT_REPO{_[0-9]+} and
# GIT_COMMIT_ID{_[0-9]+} to match.
#

GIT_SUFFIXES = $(subst GIT_REPO_,, $(filter GIT_REPO_%, $(.VARIABLES)))

# Templates for git variables and rules.  We separate the variable assignments
# from the rules so that all the variable assignments are given a chance to
# complete before those variables are used in targets or prerequisites, where
# they'll be expanded immediately.
define git-variables
ifdef GIT_REPO$(1)
ifeq ("",$(strip $(or $(GIT_BRANCH$(1)),$(GIT_COMMIT_ID$(1)))))
  $$(error GIT_BRANCH$(1) and/or GIT_COMMIT_ID$(1) must be defined)
endif

ifdef GIT_BRANCH$(1)
  GIT_BRANCH_ARG$(1) = -b $$(GIT_BRANCH$(1))
else
  GIT_BRANCH_ARG$(1) = -b master
endif

# If the label is not already defined (including to empty), set it to the version.
COMPONENT_LABEL$(1) ?= $$(COMPONENT_VERSION$(1))
# The source directory is <name>-(<label>|<version>)[-(<tag>|<branch>)][-<commit].
COMPONENT_SRC$(1) ?= $$(COMPONENT_NAME$(1))$$(COMPONENT_LABEL$(1):%=-%)$$($$(or $$(GIT_TAG$(1)),$$(GIT_BRANCH$(1))))$$(GIT_COMMIT_ID$(1):%=-%)
COMPONENT_ARCHIVE$(1) ?= $$(COMPONENT_SRC$(1)).tar.gz
# If the source is github attempt to generate an archive url.  Defining
# COMPONENT_ARCHIVE_URL here messes with prep-download.mk, which keys off of
# that variable to build download rules, so keep track of which suffixes
# generated a github archive URL, and prep-download.mk will use that list to
# remove those URLs.  If the primary (unsuffixed) archive is from github, then
# we add a dummy __BLANK__ suffix to the list, and filter that out separately.
ifeq (github,$(findstring github,$(GIT_REPO$(1))))
  COMPONENT_ARCHIVE_URL$(1) ?= $(GIT_REPO$(1))/tarball/$(GIT_BRANCH$(1))
  GITHUB_ARCHIVE_SUFFIXES += $(or $(strip $(1:_%=%)),__BLANK__)
else
  COMPONENT_ARCHIVE_SRC$(1) = git
endif

CLEAN_PATHS += $$(COMPONENT_SRC$(1))
CLOBBER_PATHS += $$(COMPONENT_ARCHIVE$(1))
SOURCE_DIR$(1) = $$(COMPONENT_DIR)/$(COMPONENT_SRC$(1))
endif
endef

define git-rules
ifdef GIT_REPO$(1)
download::	$$(USERLAND_ARCHIVES)$$(COMPONENT_ARCHIVE$(1))

# First attempt to download a cached archive of the SCM repo at the proper
# changeset ID, If COMPONENT_ARCHIVE_URL is defined try that as well.
# If that fails, create an archive by cloning the SCM repo,
# updating to the selected changeset, archiving that directory, and cleaning up
# when complete.
#
# GIT CLONE ARGS
# A shallow clone (--depth=1) to git clone takes only the top level (named)
# commits on any branches or tags and can cause use of other commit IDs to
# fail.  As such, it should never be used here as it can make it impossible to
# reliably reproduce archives created from the result since git clone (unlike
# mercurial) currently has no way of cloning to a specific commit id.
$$(USERLAND_ARCHIVES)$$(COMPONENT_ARCHIVE$(1)):	$(MAKEFILE_PREREQ)
	$$(FETCH) --file $$@ \
		$$(GIT_HASH$(1):%=--hash %) || \
		( \
	$$(FETCH) --file $$@ \
		$$(COMPONENT_ARCHIVE_URL$(1):%=--url %) || \
	(TMP_REPO=$$$$(mktemp --directory) && \
	$(GIT) clone $$(GIT_REPO$(1)) $$(GIT_BRANCH_ARG$(1)) $$$${TMP_REPO} && \
	(cd $$$${TMP_REPO} ; $(GIT) checkout \
	$$(GIT_COMMIT_ID$(1))) && \
	(cd $$$${TMP_REPO} ; $(GIT) archive --format tar.gz \
		--prefix $$(COMPONENT_SRC$(1))/ \
		$$(or $$(GIT_COMMIT_ID$(1)),$$(GIT_BRANCH$(1)))) > $$@ && \
	$(RM) -r $$$${TMP_REPO} ) && \
	( GIT_HASH=$$$$(digest -a sha256 $$@) && \
	$(GSED) -i \
		-e "s/\(GIT_HASH$(1)[[:space:]]*=[[:space:]]*\).*/\1sha256:$$$${GIT_HASH}/" \
		Makefile ))


REQUIRED_PACKAGES += developer/versioning/git

endif
endef

# Evaluate the variable assignments immediately
$(eval $(call git-variables,))
$(foreach suffix, $(GIT_SUFFIXES), $(eval $(call git-variables,_$(suffix))))

# Put the rule evaluations in a variable for deferred evaluation.
define eval-git-rules
$(eval $(call git-rules,))
$(foreach suffix, $(GIT_SUFFIXES), $(eval $(call git-rules,_$(suffix))))
endef