# Author: Jose A Ortega Ruiz <jao@member.fsf.org>
# Start date: Mon Jan 06, 2003 00:47
#
# Copyright (C) 2003, 2009, 2020 by Jose Antonio Ortega Ruiz
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
#

NOTANGLE ?= notangle
NOWEAVE ?= noweave
NOROOTS ?= noroots
CPIF ?= cpif
NODEFS ?= nodefs
NOINDEX ?= noindex

NW_LINEFORMAT ?= -L"\# %L \"%F\" %N"
NW_MAIN ?= main
NW_DOCUMENT_CLASS ?= report
NW_CONTENTS ?= contents.tex
NW_CODESIZE ?= smallcode
NW_HYPER ?= yes
NW_HYPER_OPTIONS ?= "colorlinks=true,linkcolor=blue"

f_tabbed = $(if $(subst Makefile,,$(1)),,-t8)
f_notangle = $(NOTANGLE) $(NW_LINEFORMAT) $(call f_tabbed,$(2)) -R$(2) $(1) \
             | $(CPIF) $(2);
f_latex = $(1) '\scrollmode \input '"$(2)";\
          while grep -s 'Rerun to get cross-references right' $(2).log;\
          do $(1) '\scrollmode \input '"$(2)"; done
f_roots = $(shell $(NOROOTS) $(1) | sed -r 's/^(<<)(.*)>>$$/\2/')

f_extract_inputs = $(strip $(shell \
                     cat $(1) | grep '^\\input' | \
                     sed -r 's/\\\input\{(.*)\}.*/\1/'))

f_read_nw_files = $(foreach f, $(call f_extract_inputs, $(1)), $(dir $(1))$(f))

nw_contents_files = $(foreach d, $(NW_SUBDIRS), $d/$(NW_CONTENTS))
nw_files = $(foreach f, $(nw_contents_files), $(call f_read_nw_files, $(f)))

NW_FILES = $(strip $(nw_files))

nw_sources = $(NW_FILES:%=%.nw)
local_nw_files = $(call f_extract_inputs, $(NW_CONTENTS))
local_nw_sources = $(local_nw_files:%=%.nw)
code_targets = $(local_nw_sources:%.nw=.%.tangle)
main_tex = $(NW_MAIN).tex
main_html = $(NW_MAIN).html
main_dvi = $(NW_MAIN).dvi
main_pdf = $(NW_MAIN).pdf
main_defs = $(NW_MAIN).defs
tex_files = $(NW_FILES:%=%.tex)
defs_files = $(NW_FILES:%=%.defs)
code_files = $(foreach f, $(NW_FILES), $(call f_roots, $(f).nw))
code_dirs = $(sort $(filter-out ./, \
                       $(foreach src, $(code_files), $(dir $(src)))))

%.tex : %.nw ; $(NOWEAVE) -n -indexfrom $(main_defs) $< > $@

%.defs : %.nw ;	$(NODEFS) $< > $@

$(main_tex): $(nw_contents_files) $(main_defs) $(tex_files) \
             $(NW_PRE_TEX) $(NW_POST_TEX)
	@echo "\documentclass[a4paper]{$(NW_DOCUMENT_CLASS)}" > $(main_tex)
	@echo "\usepackage{noweb}" >> $(main_tex)
	@echo "\noweboptions{longchunks}"  >> $(main_tex)
	@echo "\noweboptions{externalindex}" >> $(main_tex)
	@echo "\noweboptions{$(NW_CODESIZE)}" >> $(main_tex)
	@if [ ! -z $(NW_LANGUAGES) ]; \
          then echo "\usepackage[$(NW_LANGUAGES)]{babel}" >> $(main_tex); fi
	@echo "\usepackage[utf8]{inputenc}" >> $(main_tex)
	@for f in $(NW_PACKAGES); do echo "\usepackage{$$f}" >> $(main_tex); \
           done
	@for f in $(NW_PACKAGES_OPT); do echo "\usepackage$$f" >> $(main_tex); \
           done
	@if [ "x$(HW_HYPER)" != "xno" ]; \
           then echo "\usepackage[$(NW_HYPER_OPTIONS)]{hyperref}" >> $(main_tex); fi
	@echo "\begin{document}" >> $(main_tex)
	@for f in $(NW_PRE_TEX); do echo "\input{$$f}" >> $(main_tex); done
	@for f in $(nw_contents_files); do \
         foo=`dirname $$f`; \
         cat $$f | grep -v "^%" | \
           sed -r "s/\\\input\{(.+)\}/\\\input\{$$foo\/\1\}/" \
           >> $(main_tex); done
	@for f in $(NW_POST_TEX); do echo "\input{$$f}" >> $(main_tex); done
	@echo "\\end{document}" >> $(main_tex)

$(code_dirs): $(nw_sources)
	mkdir -p $@

$(code_targets): .%.tangle: %.nw
	$(foreach root, $(call f_roots,$<), $(call f_notangle,$<,$(root)))
	touch $@

$(main_defs): $(defs_files)
	sort -u $(defs_files) | $(CPIF) $(main_defs)

$(main_dvi): $(main_defs) $(tex_files) $(main_tex) $(nw_sources)
	latex $(NW_MAIN)
	$(NOINDEX) $(NW_MAIN)
	$(call f_latex, latex, $(NW_MAIN))

$(main_pdf): $(main_defs) $(tex_files) $(main_tex) $(nw_sources)
	pdflatex $(NW_MAIN)
	$(NOINDEX) $(NW_MAIN)
	$(call f_latex, pdflatex, $(NW_MAIN))

$(main_html): $(nw_sources)
	cat $(nw_sources) > $(NW_MAIN).nw
	$(NOWEAVE) -filter l2h -index -html $(NW_MAIN).nw | htmltoc \
          > $(main_html)
	rm -f $(NW_MAIN).nw

tangle: t_subdirs = $(filter-out ., $(NW_SUBDIRS))
tangle: $(code_dirs) $(code_targets)
	for d in $(t_subdirs); do cd $$d && $(MAKE) tangle; done

weave:  $(main_defs) $(tex_files) $(main_tex)

debug:
	@echo "sources: $(nw_sources)"
	@echo "contents files: $(nw_contents_files)"
	@echo "noweb files: $(NW_FILES)"
	@echo "code targets: $(code_targets)"
	@echo "tex files: $(tex_files)"

dvi: $(main_dvi)

pdf: $(main_pdf)

html: $(main_html)

NW_TRASH_FILES = $(code_targets) $(code_files) $(tex_files) $(defs_files) \
                 $(main_html) $(main_defs) $(main_tex)  $(main_pdf) \
                 $(NW_MAIN).out $(NW_MAIN).nwi *.toc *.log *.aux *.dvi

clean:
	rm -rf $(NW_TRASH_FILES)

.PHONY: clean dvi html weave tangle