.POSIX:
.SUFFIXES:

COLOR_BLUE:=\033[36m
COLOR_AUTO:=\033[0m
SRC=.config/aliasrc .config/inputrc .gitconfig .*profile
TGT=$(addprefix $$HOME/, $(SRC))

.PHONY: help ## Show this help menu.
help:
	@printf 'make <subcommand>\n\nsubcommand:\n'
	@awk -F '(: | ## )' '/^\.PHONY:.*?## .*$$/ {\
		printf("\t$(COLOR_BLUE)%s\t\t$(COLOR_AUTO)%s\n",$$2, $$3)\
	}' $(MAKEFILE_LIST)

.PHONY: installcheck ## Check if the dotfiles are properly linked to home.
installcheck:
	# Assert link sources match link destinations.
	for link in $(SRC); do \
	    dst_link=$$(stat -c "%N" ~/"$$link" | cut -d ' ' -f 3); \
	    src_link="$$PWD/$$link"; \
	    if [ ! "$$dst_link" = \'"$$src_link"\' ]; then \
		   printf 'Destination link matches not the source link!\n'; \
	   fi; \
	done

# RFE: Use the single suffix inference rule to enhance iteration semantics
# to actual Makefile semantics. This could probably be done by suffixing source
# links with .ln.
.PHONY: install ## Actually symlink the dotfiles to home.
install: $(SRC)
	mkdir -p $(dir $(TGT))
	for file in $(SRC); do $(RM) -r ~/$$file; ln -s $$PWD/$$file ~/$$file; done

.PHONY: uninstallcheck ## Check if dotfiles' symlinks were properly removed.
uninstallcheck:
	# Assert destination links were removed.
	for link in $(TGT); do \
		[ ! -e ~/"$$link" ] || \
			printf '%s%s\n' "$$link" "survived teardown!"; \
	done

.PHONY: uninstall ## Remove the symlinks to dotfiles.
uninstall:
	$(RM) -r $(TGT)
	for file in $(TGT); do if [ -e "$$file~" ]; then mv "$$file~" "$$file"; fi; done

.PHONY: clean ## Purge cruft (not the dotfiles payload).
clean: 
	-docker rm check_dotfiles
	-docker rmi dotfiles

# ----------------------------------------------------------------------------
# Make is not really a good system for this.
# It works with files, but this works with containers.
# Write a deployment for the test container?

.PHONY: all ## lint -> build -> check
all: lint build check

.PHONY: lint ## Lint the source repository.
lint:
	docker run --rm \
		-u "$(shell id -u):$(shell id -g)" \
		-v "$(shell pwd):/mnt" \
		-w /mnt \
		mvdan/shfmt:latest -d -sr -i 4 .config/aliasrc .*profile
	docker run --rm \
		-u "$(shell id -u):$(shell id -g)" \
		-v "$(shell pwd):/mnt" \
		-w /mnt \
		koalaman/shellcheck -x .config/aliasrc .*profile

.PHONY: build ## Build a container to system-test the dotfiles.
build:
	docker build --target test --tag dotfiles .

.PHONY: check ## Check if (un)install works in the test container.
check: build
	docker run --name="check_dotfiles" --tty -d --entrypoint sh dotfiles
	docker exec check_dotfiles make install
	docker exec check_dotfiles make installcheck
	docker exec check_dotfiles make uninstall
	docker exec check_dotfiles make uninstallcheck
	docker stop check_dotfiles
# ----------------------------------------------------------------------------