filename=$(shell basename $(shell pwd))
timestamp=$(shell date +%Y-%m-%d_%H:%M)

all: snapshot

snapshot: main.tex
	@latexmk -pdf main.tex
	@if ! cmp --silent build/main.pdf ${filename}_*.pdf; then \
		touch ${filename}_tmp.pdf; \
		rm ${filename}*.pdf; \
		cp build/main.pdf ${filename}_${timestamp}.pdf; \
		echo "Updated"; \
	fi

clean:
	@rm -rf build 2>/dev/null