#!/usr/bin/make -f

PKGNAME := string-lerp

fallback = $(firstword $(shell command -v $(1)) $(2))

git = $(shell GIT_DIR=$(firstword $(2) $(srcdir) .)/.git $(GIT) $(1))
git_ls-tree = $(call git,ls-tree -r --name-only $(1),$(2))
git_tag = $(call git,name-rev --tags --name-only $(call git,rev-parse $(1),$(2)),$(2))

GIT ?= git
NPM ?= npm
NPMBINDIR := ./node_modules/.bin
JSTEST ?= $(NPMBINDIR)/jstest
JSHINT ?= $(call fallback,jshint,$(NPMBINDIR)/jshint)
UGLIFY ?= $(call fallback,uglifyjs,$(NPMBINDIR)/uglifyjs)
SOURCES := string-lerp.js
UGLIFIED = $(SOURCES:.js=.min.js)

TESTS = $(wildcard tests/*.js)
LINT_TARGETS = $(patsubst %.js,build/stamp/%.lint,$(SOURCES))
TEST_TARGETS = $(patsubst %.js,build/stamp/%.test,$(SOURCES)) \
               $(patsubst tests/%.js,build/stamp/%.test,$(TESTS))

.PHONY: all check lint test ugly dist clean distclean install

all:
	@echo "Interesting targets:"
	@echo "    lint - validate source (with jshint)"
	@echo "    test - run tests (with jstest)"
	@echo "    ugly - generate minified/mangled source files"
	@echo "    dist - generate redistributables (if git tagged)"
	@echo
	@echo "(Running these may download packages from npm.)"
	@echo

%.min.js: %.js | $(UGLIFY)
	$(UGLIFY) --comments -m < $< > $@

build/stamp/%.lint: %.js | $(JSHINT)
	@mkdir -p $(@D)
	$(JSHINT) $<
	@touch $@

build/stamp/%.test: tests/%.js %.js | $(JSTEST)
	@mkdir -p $(@D)
	@echo $(JSTEST) $<
	@$(JSTEST) $< > $@ || (cat $@ && rm -f $@ && exit 1)
	@touch $@

build/stamp/%.test: tests/%.js $(SOURCES) | $(JSTEST)
	@mkdir -p $(@D)
	@echo $(JSTEST) $<
	@$(JSTEST) $< > $@ || (cat $@ && rm -f $@ && exit 1)
	@touch $@

check: lint test

lint: $(LINT_TARGETS)

test: $(TEST_TARGETS)

ugly: $(UGLIFIED)

build/dist/$(PKGNAME)-undefined.zip build/dist/$(PKGNAME)-undefined.tar.gz:
	$(error Distributables must be tagged or explicitly versioned)

.SECONDEXPANSION:
build/dist/$(PKGNAME)-%.zip: $$(call git_ls-tree,$$*)
	@mkdir -p $(@D)
	$(GIT) archive --prefix=$(PKGNAME)-$*/ --output=$@ $*

.SECONDEXPANSION:
build/dist/$(PKGNAME)-%.tar.gz: $$(call git_ls-tree,$$*)
	@mkdir -p $(@D)
	$(GIT) archive --prefix=$(PKGNAME)-$*/ --output=$@ $*

dist: check $(addprefix build/dist/$(PKGNAME)-$(call git_tag,HEAD),.zip .tar.gz)

clean:
	$(RM) -r build
	$(RM) $(UGLIFIED)

distclean: clean
	$(RM) -r node_modules

install: check
	$(NPM) install -g .

$(JSTEST):
	$(NPM) install jstest

$(JSHINT):
	$(NPM) install jshint

$(UGLIFY):
	$(NPM) install uglify-js