.POSIX:

# Standard GNU-ish install variables, so a packager can redirect everything:
#   make install PREFIX=/usr DESTDIR=/tmp/pkg
DESTDIR    ?=
PREFIX     ?= $(HOME)/.local
BINDIR     := $(DESTDIR)$(PREFIX)/bin
MANDIR     := $(DESTDIR)$(PREFIX)/share/man/man1

BIN     := prognosis
DIST    := dist
MODULE  := github.com/lukaszkasprzak/prognosis

# Version comes from git when there is a tag, "dev" otherwise, and is stamped
# into the binary so -version reports something meaningful.
VERSION ?= $(shell git describe --tags --always --dirty 2>/dev/null || echo dev)
GOFLAGS := -trimpath
LDFLAGS := -s -w -X main.version=$(VERSION)

PLATFORMS := linux/amd64 linux/arm64 android/arm64 darwin/amd64 darwin/arm64 freebsd/amd64

.PHONY: help build install uninstall test vet fmt lint ci cross release install-hooks clean

help: ## show this help
	@grep -E '^[a-z-]+:.*?## .*$$' $(MAKEFILE_LIST) | sort | \
	  awk 'BEGIN {FS = ":.*?## "}; {printf "  \033[1m%-14s\033[0m %s\n", $$1, $$2}'
	@echo
	@echo "  version: $(VERSION)   prefix: $(PREFIX)"

build: ## build ./$(BIN)
	go build $(GOFLAGS) -ldflags "$(LDFLAGS)" -o $(BIN) ./cmd/prognosis

install: build ## install the binary and man page
	mkdir -p $(BINDIR) $(MANDIR)
	# rm first: the target may be a symlink, and cp follows symlinks.
	rm -f $(BINDIR)/$(BIN)
	install -m 755 $(BIN) $(BINDIR)/$(BIN)
	install -m 644 man/prognosis.1 $(MANDIR)/prognosis.1
	@echo "installed $(BINDIR)/$(BIN) and $(MANDIR)/prognosis.1"

uninstall: ## remove the installed binary and man page
	rm -f $(BINDIR)/$(BIN) $(MANDIR)/prognosis.1

test: ## run the tests
	go test ./...

vet: ## go vet
	go vet ./...

fmt: ## gofmt the tree
	gofmt -w .

lint: ## check the man page renders without warnings
	@out=$$(man --warnings -l man/prognosis.1 2>&1 >/dev/null); \
	  test -z "$$out" || { echo "man page warnings:"; echo "$$out"; exit 1; }
	@echo "man page ok"

ci: ## the gate: gofmt, vet, tests, man page, and no third-party deps
	@test -z "$$(gofmt -l .)" || { echo "gofmt needed:"; gofmt -l .; exit 1; }
	go vet ./...
	go test ./...
	@$(MAKE) --no-print-directory lint
	@deps=$$(go list -deps ./... | grep -E '^[a-z0-9-]+\.[a-z]+/' | grep -v '^$(MODULE)' || true); \
	  test -z "$$deps" || { echo "third-party dependencies crept in:"; echo "$$deps"; exit 1; }
	@echo "ci ok"

cross: ## cross-compile every platform into $(DIST)/
	@mkdir -p $(DIST)
	@for p in $(PLATFORMS); do \
	  os=$${p%/*}; arch=$${p#*/}; \
	  echo "  $$os/$$arch"; \
	  CGO_ENABLED=0 GOOS=$$os GOARCH=$$arch \
	    go build $(GOFLAGS) -ldflags "$(LDFLAGS)" -o $(DIST)/$(BIN)-$$os-$$arch ./cmd/prognosis || exit 1; \
	done
	@ls -la $(DIST)

release: ## tag a release: make release VERSION=0.2.0 (add its CHANGELOG entry first)
	@test "$(VERSION)" != "dev" || { echo "give a version: make release VERSION=0.2.0"; exit 1; }
	@grep -q "^## $(VERSION)" CHANGELOG.md || \
	  { echo "CHANGELOG.md has no '## $(VERSION)' entry; write it first"; exit 1; }
	@test -z "$$(git status --porcelain)" || { echo "working tree is dirty"; exit 1; }
	@$(MAKE) --no-print-directory ci
	git tag -a v$(VERSION) -m "prognosis v$(VERSION)"
	@echo "tagged v$(VERSION); push it with: git push --tags"

install-hooks: ## install the pre-push hook that runs make ci
	install -m 755 scripts/hooks/pre-push .git/hooks/pre-push
	@echo "installed .git/hooks/pre-push"

clean: ## remove build artifacts
	rm -rf $(BIN) $(DIST)