# This Makefile generates the manual pages from the markdown README.mds. It depends
# on https://github.com/mmarkdown/mmark to be installed. Generally we want this to be
# updated before doing a release. The Debian package, for instance, looks at these pages
# and will install them on your system.

MMARK_VERSION:=2.2.47
PLUGINS:=$(wildcard plugin/*/README.md)
READMES:=$(subst plugin/,,$(PLUGINS))
READMES:=$(subst /README.md,,$(READMES))
PLUGINS:=$(subst plugin/,coredns-,$(PLUGINS))
PLUGINS:=$(subst /README.md,(7),$(PLUGINS))

all: mmark man/coredns.1 man/corefile.5 plugins

GO           ?= go
GOHOSTOS     ?= $(shell $(GO) env GOHOSTOS)
GOHOSTARCH   ?= $(shell $(GO) env GOHOSTARCH)
GO_BUILD_PLATFORM ?= $(GOHOSTOS)_$(GOHOSTARCH)

FIRST_GOPATH := $(firstword $(subst :, ,$(shell $(GO) env GOPATH)))
MMARK_BIN    := $(FIRST_GOPATH)/bin/mmark
MMARK        := $(FIRST_GOPATH)/bin/mmark -man

MMARK_URL := https://github.com/mmarkdown/mmark/releases/download/v$(MMARK_VERSION)/mmark_$(MMARK_VERSION)_$(GO_BUILD_PLATFORM).tgz

# SHA-256 checksums for mmark v2.2.47 release tarballs.
# See: https://github.com/mmarkdown/mmark/releases/tag/v2.2.47
MMARK_SHA256_darwin_amd64  := 941e963489e328c9da188629688438f9f3e93b6a4895c6ef943d55fbbfa84a3c
MMARK_SHA256_darwin_arm64  := 641cbc566edec29dd989ac15432b7f007be54ebc163cf6d98cd1d3df295ef9c4
MMARK_SHA256_linux_amd64   := e0585cc9628c562e0f1be36e45221e84c6fc84957c999168ce4ba35594264ff2
MMARK_SHA256_linux_arm     := f6e1059c032b9ec0a74da40d8e901968d0bb41d92a160ef4782febbbf298d22d
MMARK_SHA256_linux_arm64   := 9a3c9b2e525b5addf97f968ec28829947520f628fdf4850134be784e220149ca
MMARK_SHA256_windows_amd64 := 9c73231e4427651d1f7911d4a9014aa2d87e735aac9c93e4e400061bc1de6714
MMARK_SHA256 := $(MMARK_SHA256_$(GO_BUILD_PLATFORM))

.PHONY: mmark
mmark: $(MMARK_BIN)

$(MMARK_BIN):
	$(eval MMARK_TMP := $(shell mktemp -d))
	curl -s -L -o $(MMARK_TMP)/mmark.tgz $(MMARK_URL)
	@if [ -z "$(MMARK_SHA256)" ]; then \
		echo "error: no known checksum for platform $(GO_BUILD_PLATFORM)" >&2; exit 1; \
	fi
	@echo "$(MMARK_SHA256)  $(MMARK_TMP)/mmark.tgz" | shasum -a 256 -c -
	tar -xzf $(MMARK_TMP)/mmark.tgz -C $(MMARK_TMP)
	mkdir -p $(FIRST_GOPATH)/bin
	cp $(MMARK_TMP)/mmark $(FIRST_GOPATH)/bin/mmark
	rm -r $(MMARK_TMP)

man/coredns.1: coredns.1.md
	@printf '%%%%%%\n title = "coredns 1"\n area = "CoreDNS"\n workgroup = "CoreDNS"\n%%%%%%\n\n' > $@.header
	@cat $@.header $< > $@.md && rm $@.header
	@sed -e "s/@@PLUGINS@@/$(PLUGINS)/" $@.md > $@.md.tmp && mv $@.md.tmp $@.md
	$(MMARK) $@.md > $@ && rm $@.md

man/corefile.5: corefile.5.md
	@printf '%%%%%%\n title = "corefile 5"\n area = "CoreDNS"\n workgroup = "CoreDNS"\n%%%%%%\n\n' > $@.header
	@cat $@.header $< > $@.md && rm $@.header
	$(MMARK) $@.md > $@ && rm $@.md

.PHONY: plugins
plugins:
	for README in $(READMES); do \
	    $(MAKE) -f Makefile.doc man/coredns-$$README.7; \
	done

man/coredns-%.7: plugin/%/README.md
	@printf '%%%%%%\n title = "%s 7"\n area = "CoreDNS"\n workgroup = "CoreDNS Plugins"\n%%%%%%\n\n' "`basename $@ | sed s/\.7//`" > $@.header
	@cat $@.header $< > $@.md && rm $@.header
	@sed -e '/^# .*/d' $@.md > $@.md.tmp && mv $@.md.tmp $@.md
	$(MMARK) $@.md > $@ && rm $@.md

PHONY: clean
clean:
	rm -f man/*