BINNAME = gomonop
BINDIR = $(CURDIR)/bin
DISTDIR = $(CURDIR)/dist
TARGETS = linux/amd64 linux/386 linux/arm linux/arm64
STATICFILES = README.md LICENSE

SRC := $(shell find . -type f -name '*.go' -not -path './dist/*' -print) go.mod go.sum
GOHOSTOS = $(shell go env GOHOSTOS)
GOHOSTARCH ?= $(shell go env GOHOSTARCH)

GIT_TAG    = $(shell git describe --tags --abbrev=0 --exact-match 2>/dev/null)
GIT_COMMIT ?= $(shell git rev-parse --short HEAD 2>/dev/null)
GIT_STATUS ?= $(shell test -n "`git status --porcelain`" && echo "dirty" || echo "clean")

ifneq ($(VERSION),)
	BINARY_VERSION = $(VERSION)
endif
BINARY_VERSION ?= $(GIT_TAG)

LDFLAGS += -w -s
ifneq ($(BINARY_VERSION),)
	LDFLAGS += -X nocternity.net/gomonop/pkg/version.version=${BINARY_VERSION}
endif
LDFLAGS += -X nocternity.net/gomonop/pkg/version.commit=${GIT_COMMIT}
LDFLAGS += -X nocternity.net/gomonop/pkg/version.status=${GIT_STATUS}

# Use bash as the shell, mostly for -o pipefail
SHELL = /usr/bin/env bash


.PHONY: all
all: build

# ---------------
# Basic building

.PHONY: build
build: GOOS=$(GOHOSTOS)
build: GOARCH=$(GOHOSTARCH)
build: build-target symlink

.PHONY: symlink
symlink:
	@ln -sf $(BINDIR)/$(GOOS)-$(GOARCH)/$(BINNAME) $(BINDIR)/$(BINNAME)

.PHONY: build-target
build-target: LDFLAGS += -X nocternity.net/gomonop/pkg/version.target=${GOOS}/${GOARCH}
build-target: $(BINDIR)/$(GOOS)-$(GOARCH)/$(BINNAME)

$(BINDIR)/$(GOOS)-$(GOARCH)/$(BINNAME): $(SRC)
	@mkdir -p $(BINDIR)/$(GOOS)-$(GOARCH)
	@CGO_ENABLED=0 go build -ldflags "$(LDFLAGS)" -o $(BINDIR)/$(GOOS)-$(GOARCH)/$(BINNAME) .

.PHONY: test
test:
	@go test -v ./...

.PHONY: lint
lint:
	@go run -modfile=tools/go.mod github.com/golangci/golangci-lint/cmd/golangci-lint run

# ----------------
# Cross compiling

.PHONY: build-cross
build-cross:
	@for target in $(TARGETS); do \
		$(MAKE) build-target GOOS=`echo $$target | cut -d / -f 1` GOARCH=`echo $$target | cut -d / -f 2`; \
	done

# ----------
# Packaging

.PHONY: dist
dist: GOOS=$(GOHOSTOS)
dist: GOARCH=$(GOHOSTARCH)
dist: dist-target

.PHONY: dist-all
dist-all: dist-source
	@set -eu -o pipefail; \
	for target in $(TARGETS); do \
		$(MAKE) dist-target GOOS=`echo $$target | cut -d / -f 1` GOARCH=`echo $$target | cut -d / -f 2`; \
	done; \
	mkdir -p $(DISTDIR)/release; \
	mv $(DISTDIR)/$(BINNAME)-$(BINARY_VERSION)*.tar.xz $(DISTDIR)/release

.PHONY: dist-source
dist-source:
	@set -eu -o pipefail; \
	if [ -z "$(BINARY_VERSION)" ]; then \
		echo "No version set"; \
		exit 1; \
	fi; \
	rm -rf $(DISTDIR)/$(BINNAME)-$(BINARY_VERSION); \
	mkdir -p $(DISTDIR)/$(BINNAME)-$(BINARY_VERSION); \
	for f in $(SRC) $(STATICFILES); do \
		install -m 644 -D $$f $(DISTDIR)/$(BINNAME)-$(BINARY_VERSION)/$$f; \
	done; \
	( \
		echo "VERSION = ${BINARY_VERSION}"; \
		echo "GIT_COMMIT = ${GIT_COMMIT}"; \
		echo "GIT_STATUS = ${GIT_STATUS}"; \
		cat Makefile; \
	) > $(DISTDIR)/$(BINNAME)-$(BINARY_VERSION)/Makefile; \
	cd $(DISTDIR); \
	tar cJf $(BINNAME)-$(BINARY_VERSION).tar.xz $(BINNAME)-$(BINARY_VERSION)

.PHONY: dist-target
dist-target: build-target
	@set -eu -o pipefail; \
	if [ -z "$(BINARY_VERSION)" ]; then \
		echo "No version set"; \
		exit 1; \
	fi; \
	rm -rf $(DISTDIR)/$(BINNAME)-$(BINARY_VERSION)-$(GOOS)-$(GOARCH); \
	mkdir -p $(DISTDIR)/$(BINNAME)-$(BINARY_VERSION)-$(GOOS)-$(GOARCH); \
	cp $(BINDIR)/$(GOOS)-$(GOARCH)/$(BINNAME) $(DISTDIR)/$(BINNAME)-$(BINARY_VERSION)-$(GOOS)-$(GOARCH); \
	for f in $(STATICFILES); do \
		cp $$f $(DISTDIR)/$(BINNAME)-$(BINARY_VERSION)-$(GOOS)-$(GOARCH); \
	done; \
	cd $(DISTDIR); \
	tar cJf $(BINNAME)-$(BINARY_VERSION)-$(GOOS)-$(GOARCH).tar.xz $(BINNAME)-$(BINARY_VERSION)-$(GOOS)-$(GOARCH)

# --------
# Cleanup

.PHONY: clean
clean:
	@rm -rf $(BINDIR) $(DISTDIR)