# -*- makefile -*-

clean::
	fakeroot debian/rules clean
.PHONY: clean

prepare::
.PHONY: prepare

deb: prepare
	dpkg-buildpackage -us -uc -rfakeroot -I.git -I.gitignore -I.gitmodules
.PHONY: deb

###########################################################################
# Generate debian/changelog from git log

NAME       := $(shell awk '/^Source:/{print $$2}' debian/control)
CLOGDIR    := .git/changelogs
CHANGELOGS := $(shell lasttag=HEAD;						\
		      (git tag -l 'v*'; echo)					\
			  | while read tag; do					\
			      echo $(CLOGDIR)/$${tag}$${tag:+-}$$lasttag;	\
			      lasttag=$$tag;					\
			  done)

# Author/Date formating could be as simple as  git log --format=' -- %an <%ae>  %cD'
# however, we want the tagger not the author and  git log  doesn't show tags, only commits ...
$(CHANGELOGS): %:
	@echo "generating $@"
	@mkdir -p "$(CLOGDIR)"
	@(                                                                                       \
	    version="$@"; version="$${version#$(CLOGDIR)/}";                                     \
	    from="$${version%-*}"; version="$${version#*-}"; to="$$version";                     \
	    if [ "$$from" = "$$to" ]; then from=""; fi;                                  \
	    release="unstable";                                                                  \
	    if [ "$$version" = "HEAD" ]; then                                                    \
		version="`git describe --tag --match='v*' | sed -e 's/-/~/' -e 's/-/./g'`";      \
		release="UNRELEASED";                                                            \
	    fi;                                                                                  \
	    version="$${version#v}";                                                             \
	    echo "$(NAME) ($$version) $$release; urgency=low";                                   \
	    echo;                                                                                \
	    git log --format='  * [%h] %s' $$from$${from:+..}$$to;                               \
	    date="`echo $$to | git cat-file --batch                                              \
		       | sed -n                                                                  \
			     -e 's/^\(tagger\|committer\) \(.*\)00$$/\2/'                        \
			     -eT -e 'y/+-/-+/' -ep`";                                            \
	    author="$${date% * *}"; date="$${date#$$author }"; zone="$${date#* }";               \
	    date="`TZ="UTC$$zone" date -d "1/1/1970 0:0 UTC + $${date% *} seconds" --rfc-2822`"; \
	    echo; echo " -- $$author  $$date"; echo;                                             \
	) >$@ || (rm -f $@; false)
.PHONY: $(word 1,$(CHANGELOGS)) # The first changelog entry must be recreated on each call

debian/changelog: $(CHANGELOGS)
	cat $^ > $@ || (rm -f $@; false)

clean::
	rm -f debian/changelog
	rm -rf $(CLOGDIR)

prepare:: debian/changelog