.PHONY: all, clean-dist, clean

ifeq ($(origin IMAGE_DIR),undefined)
$(error $$IMAGE_DIR is not set)
endif

# Files for distribution
DIST_DIR ?= dist
# Temporary build artifacts
BUILD_DIR ?= build

THUMB_DIR := $(DIST_DIR)/thumbs

images := $(shell find $(IMAGE_DIR) -iname '*.jpg')
image_names_cs := $(notdir $(images))
image_names := $(shell echo $(image_names_cs) | tr A-Z a-z)
dist_images := $(addprefix $(DIST_DIR)/,$(image_names))
dist_thumbs := $(patsubst $(DIST_DIR)/%.jpg,$(THUMB_DIR)/%.webp,$(dist_images))

extra_files := $(wildcard extra/*)
dist_extra_files := $(extra_files:%=$(DIST_DIR)/%)

define copy_image_rule =
$(DIST_DIR)/$(1): $(shell find $(IMAGE_DIR) -iname $(1))
	@mkdir -p $(DIST_DIR)
	cp --preserve $$< $$@
endef

build_metas := $(dist_images:$(DIST_DIR)/%.jpg=$(BUILD_DIR)/%.meta.json)
dist_html := $(dist_images:$(DIST_DIR)/%.jpg=$(DIST_DIR)/%.html)

### RULES ###

all: $(dist_images) $(dist_thumbs) $(dist_extra_files) $(dist_html) $(DIST_DIR)/all.zip $(DIST_DIR)/index.html

clean-dist:
	rm -rf $(DIST_DIR)

clean: clean-dist
	rm -rf $(BUILD_DIR)

$(foreach f,$(image_names),$(eval $(call copy_image_rule,$(f))))

$(THUMB_DIR)/%.webp: $(DIST_DIR)/%.jpg
	@mkdir -p $(THUMB_DIR)
	magick $< -strip -thumbnail 300x300 $@

$(BUILD_DIR)/index.json: $(build_metas) build-index.py
	./build-index.py $(filter-out build-index.py,$^) > $@

$(BUILD_DIR)/%.meta.json: $(DIST_DIR)/%.jpg $(THUMB_DIR)/%.webp extract-metadata.py
	@mkdir -p $(BUILD_DIR)
	./extract-metadata.py --root $(DIST_DIR) --dist-path $(patsubst $(BUILD_DIR)/%.meta.json,$(DIST_DIR)/%.html,$@) --key $(patsubst $(BUILD_DIR)/%.meta.json,%,$@) --thumbnail $(patsubst $(BUILD_DIR)/%.meta.json,$(THUMB_DIR)/%.webp,$@) $< > $@

$(DIST_DIR)/index.html: $(BUILD_DIR)/index.json index.hbs
	@mkdir -p $(DIST_DIR)
	handlebars-cli index.hbs @$(BUILD_DIR)/index.json > $@

$(DIST_DIR)/%.html: $(BUILD_DIR)/%.meta.json $(BUILD_DIR)/index.json photo.hbs
	@mkdir -p $(DIST_DIR)
	cat $(BUILD_DIR)/index.json | jq .index.$(patsubst $(BUILD_DIR)/%.meta.json,%,$<) | handlebars-cli photo.hbs @/dev/stdin > $@

$(DIST_DIR)/extra/%: extra/%
	@mkdir -p $(DIST_DIR)/extra
	cp -r $< $@

$(DIST_DIR)/all.zip: $(dist_images)
	@mkdir -p $(DIST_DIR)
	zip --junk-paths $@ $^