#
# Example makefile using mjotex and a BibTeX references database.
#

# The latex compiler.
LATEX = pdflatex -file-line-error -halt-on-error

# The name of this document.
PN := paper

# A space-separated list of bib files. These must all belong to paths
# contained in your $BIBINPUTS environment variable.
BIBS = references.bib

# A space-separated list of the mjotex files that you use. The path to
# mjotex must be contain in your $TEXINPUTS environment variable.
MJOTEX  = mjo-algorithm.tex mjo-arrow.tex mjo-common.tex mjo-cone.tex
MJOTEX += mjo-convex.tex mjo-font.tex mjo-linear_algebra.tex mjo-listing.tex
MJOTEX += mjo-misc.tex mjo-proof_by_cases.tex mjo-theorem.tex
MJOTEX += mjo-theorem-star.tex mjo-topology.tex

# Use kpsewhich (from the kpathsea suite) to find the absolute paths
# of the bibtex/mjotex files listed in in $(BIBS)/$(MJOTEX). The SRCS
# variable should contain all (Bib)TeX source files for the document.
SRCS = $(PN).tex $(shell kpsewhich $(BIBS)) $(shell kpsewhich $(MJOTEX))


# The first target is the default, so put the PDF document first.
#
# The voodoo here is to avoid rebuilding the project when nothing has
# changed. Each compilation pass with pdflatex will produce a new aux
# file, even if nothing has changed. That cases Make to think that we
# need to regenerate the bbl file, which in turn means we need to
# rebuild the whole project...
#
# To avoid that, we save a copy of the current aux file and compare it
# to the new one afterwards. If the files are the same, great, put the
# old one (with the old timestamp) back. If not, we need to compile
# again, so we just invoke $(MAKE) again on this target.
#
# The process is kind of like finding a fixpoint of `make` with
# respect to the contents of the aux file.
#
# Why use the aux file and not the PDF, which is what we really care
# about? The pdflatex tool currently embeds the creation/modification
# time into the PDF, so every new version will differ from the last,
# making comparisons meaningless. This is fixed in pdftex v1.40.17
# thanks to Debian's SOURCE_DATE_EPOCH initiative. When that version
# of pdflatex makes it into TeX Live 2016, we can replace this junk
# with something smarter
#
$(PN).pdf: $(SRCS) $(PN).aux $(PN).bbl
	mv $(PN).aux $(PN).aux.bak
	$(LATEX) $< && $(LATEX) $<
	if cmp -s $(PN).aux $(PN).aux.bak; then \
		mv $(PN).aux.bak $(PN).aux; \
	else \
		$(MAKE) $@; \
	fi;

$(PN).aux: $(SRCS)
	$(LATEX) $<

$(PN).bbl: $(PN).aux
	bibtex $<


# Clean up leftover junk.
.PHONY: clean
clean:
	rm -f *.{out,nav,snm,toc,aux,log,pdf,bcf,xml,bbl,blg,bib}
	rm -rf dist/



# If this document will be published, the publisher isn't going to
# have your BibTeX database or your mjotex files. So, you need to
# package them up along with the code for your document. This target
# will create a "dist" directory and copy the necessary stuff there.
#
.PHONY: dist
dist: $(PN).bbl
	mkdir -p dist
	cp $(SRCS) $(PN).bbl dist/