# Packages included in BR2_EXTERNAL are not part of buildroot, so they
# should not be included in the manual.
manual-update-lists: manual-check-dependencies-lists $(BUILD_DIR)/docs/$(pkgname)
	$(Q)$(call MESSAGE,"Updating the manual lists...")
	$(Q)BR2_DEFCONFIG="" TOPDIR=$(TOPDIR) O=$(BUILD_DIR)/docs/$(pkgname) \
		BR2_EXTERNAL=$(TOPDIR)/support/dummy-external \
		python -B $(TOPDIR)/support/scripts/gen-manual-lists.py

manual-prepare-sources: manual-rsync manual-update-lists

# we can't use suitable-host-package here because that's not available in
# the context of 'make release'
manual-check-dependencies:
	$(Q)if [ -z "$(shell support/dependencies/check-host-asciidoc.sh)" ]; then \
		echo "You need a sufficiently recent asciidoc on your host" \
			"to generate the manual"; \
		exit 1; \
	fi
	$(Q)if [ -z "`which w3m 2>/dev/null`" ]; then \
		echo "You need w3m on your host to generate the manual"; \
		exit 1; \
	fi

manual-check-dependencies-pdf:
	$(Q)if [ -z "`which dblatex 2>/dev/null`" ]; then \
		echo "You need dblatex on your host to generate the pdf manual"; \
		exit 1; \
	fi

manual-check-dependencies-lists:
	$(Q)if ! python -c "import argparse" >/dev/null 2>&1 ; then \
		echo "You need python with argparse on your host to generate" \
			"the list of packages in the manual"; \
		exit 1; \
	fi

# PDF manual generation is broken because of a bug in xsltproc program provided
# by libxslt <=1.1.28, which does not honor an option we need to set.
# Fortunately, this bug is already fixed upstream:
#   https://gitorious.org/libxslt/libxslt/commit/5af7ad745323004984287e48b42712e7305de35c
#
# So, bail out when trying to build the pdf manual using a buggy version of the
# xsltproc program.
#
# So, to overcome this issue and being able to build the pdf manual, you can
# build xsltproc from it source repository, then run:
#   $ PATH=/path/to/custom-xsltproc/bin:${PATH} make manual
MANUAL_XSLTPROC_IS_BROKEN = \
	$(shell xsltproc --maxvars 0 >/dev/null 2>/dev/null || echo y)

################################################################################
# GENDOC_INNER -- generates the make targets needed to build a specific type of
#                 asciidoc documentation.
#
#  argument 1 is the name of the document and must be a subdirectory of docs/;
#             the top-level asciidoc file must have the same name
#  argument 2 is the type of document to generate (-f argument of a2x)
#  argument 3 is the document type as used in the make target
#  argument 4 is the output file extension for the document type
#  argument 5 is the human text for the document type
#  argument 6 (optional) are extra arguments for a2x
#
# The variable <DOCUMENT_NAME>_SOURCES defines the dependencies.
#
# Since this function will be called from within an $(eval ...)
# all variable references except the arguments must be $$-quoted.
################################################################################
define GENDOC_INNER
$(1): $(1)-$(3)
.PHONY: $(1)-$(3)
$(1)-$(3): $$(O)/docs/$(1)/$(1).$(4)

manual-check-dependencies-$(3):

MANUAL_$(2)_ASCIIDOC_CONF = docs/$(1)/asciidoc-$(2).conf
ifneq ($$(wildcard $$(MANUAL_$(2)_ASCIIDOC_CONF)),)
MANUAL_$(2)_ASCIIDOC_OPTS += -f $$(MANUAL_$(2)_ASCIIDOC_CONF)
endif

# Handle a2x warning about --destination-dir option only applicable to HTML
# based outputs. So:
# - use the --destination-dir option if possible (html and split-html),
# - otherwise copy the generated manual to the output directory
MANUAL_$(2)_A2X_OPTS =
ifneq ($$(filter $(3),html split-html),)
MANUAL_$(2)_A2X_OPTS += --destination-dir="$$(@D)"
else
define MANUAL_$(2)_INSTALL_CMDS
	$$(Q)cp -f $$(BUILD_DIR)/docs/$(1)/$(1).$(4) $$(@D)
endef
endif

ifeq ($(4)-$$(MANUAL_XSLTPROC_IS_BROKEN),pdf-y)
$$(O)/docs/$(1)/$(1).$(4):
	$$(warning PDF manual generation is disabled because of a bug in \
		xsltproc. To be able to generate the PDF manual, you should \
		build xsltproc from the libxslt sources >=1.1.29 and pass it \
		to make through the command line: \
		'PATH=/path/to/custom-xsltproc/bin:$$$${PATH} make manual-pdf')
else
$$(O)/docs/$(1)/$(1).$(4): $$($$(call UPPERCASE,$(1))_SOURCES) \
			   manual-check-dependencies \
			   manual-check-dependencies-$(3) \
			   manual-prepare-sources
	$$(Q)$$(call MESSAGE,"Generating $(5) $(1)...")
	$$(Q)mkdir -p $$(@D)
	$$(Q)a2x $(6) -f $(2) -d book -L -r $$(TOPDIR)/docs/images \
		$$(MANUAL_$(2)_A2X_OPTS) \
		--asciidoc-opts="$$(MANUAL_$(2)_ASCIIDOC_OPTS)" \
		$$(BUILD_DIR)/docs/$(1)/$(1).txt
# install the generated manual
	$$(MANUAL_$(2)_INSTALL_CMDS)
endif
endef

################################################################################
# GENDOC -- generates the make targets needed to build asciidoc documentation.
#
# The variable <DOCUMENT_NAME>_SOURCES defines the dependencies.
################################################################################
define GENDOC
$$(BUILD_DIR)/docs/$(pkgname):
	$$(Q)mkdir -p $$@

$(pkgname)-rsync: $$(BUILD_DIR)/docs/$(pkgname)
	$$(Q)$$(call MESSAGE,"Preparing the $(pkgname) sources...")
	$$(Q)rsync -a docs/$(pkgname)/ $$^

$(call GENDOC_INNER,$(pkgname),xhtml,html,html,HTML,\
	--xsltproc-opts "--stringparam toc.section.depth 1")
$(call GENDOC_INNER,$(pkgname),chunked,split-html,chunked,split HTML,\
	--xsltproc-opts "--stringparam toc.section.depth 1")
# dblatex needs to pass the '--maxvars ...' option to xsltproc to prevent it
# from reaching the template recursion limit when processing the (long) target
# package table and bailing out.
$(call GENDOC_INNER,$(pkgname),pdf,pdf,pdf,PDF,\
	--dblatex-opts "-P latex.output.revhistory=0 -x '--maxvars 100000'")
$(call GENDOC_INNER,$(pkgname),text,text,text,text)
$(call GENDOC_INNER,$(pkgname),epub,epub,epub,ePUB)
clean: $(pkgname)-clean
$(pkgname)-clean:
	$$(Q)$$(RM) -rf $$(BUILD_DIR)/docs/$(pkgname)
.PHONY: $(pkgname) $(pkgname)-clean manual-update-lists
endef

MANUAL_SOURCES = $(sort $(wildcard docs/manual/*.txt) $(wildcard docs/images/*))
$(eval $(call GENDOC))