convert=/usr/bin/convert
identify=/usr/bin/identify
imgs_nb=$(patsubst %_nb.png,%,$(wildcard *_nb.png))

.PHONY: all_wrapped
all_wrapped: remove_spaces
	@$(MAKE) all

.PHONY: remove_spaces
remove_spaces:
	@find . -name "* *" -exec rename -v 's/ /_/g' '{}' ';'

#IMG = $(shell ls --quoting-style="escape" */*.jpeg */*.JPEG */*.jpg */*.JPG */*.png */*.PNG */*.gif */*.GIF 2>/dev/null)
#IMG = $(wildcard  */*.jpeg */*.JPEG */*.jpg */*.JPG */*.png */*.PNG */*.gif */*.GIF)
#IMG = $(shell find . -iregex ".*\.\(jpeg\|jpg\|gif\|png\)"|grep -v "\.img/")

# ignore directories where there is a .img/ignore file
IGNORE = $(shell find . -path '*/.img/ignore'|sed -r 's@^(.*)/.img/ignore$$@-path '\''\1'\''@;2,$$s/^/-o /')
FORCE = $(shell find . -path '*/.img/force'|sed -r 's@^(.*)/.img/force$$@'\''\1'\''@')
# find picture files not in $(IGNORE) directories nor in */.img
IMG = $(shell find . $(FORCE) \( -path '*/.img' $(if $(IGNORE),-o $(IGNORE)) \) -prune -o \( -iregex '.*\.\(jpeg\|jpg\|gif\|png\)' -print \))

#TOREMOVE = $(filter-out $(THUMBS) $(SIZES) $(TITLES) $(DESCRIPTIONS),$(shell find . -type f \( $(IGNORE) -name 'sdfsdfsdfsdf' \) -prune -o \( -iregex '.*/\.img/.*' -print \)|grep -v .exists))

.PHONY: all clean
all: $(imgs:%=%_col.png)
#	@rm -f $(TOREMOVE) 2>/dev/null || true

define IMG_template
THUMBS += $(dir $(i)).img/thumb/$(notdir $(i))
SIZES += $(dir $(i)).img/size/$(notdir $(i))
TITLES += $(dir $(i)).img/title/$(notdir $(i))
DESCRIPTIONS += $(dir $(i)).img/description/$(notdir $(i))
$(dir $(i)).img/thumb/$(notdir $(i)): $(i) $(dir $(i)).img/thumb/.exists $(dir $(i)).img/size/.exists
	@echo -n "generating thumbnail for $$<..."
	@$(convert) -size "512x512>" -thumbnail "128x128>" "$$<" "$$@" \
	&& echo "done."
$(dir $(i)).img/size/$(notdir $(i)): $(i)
	@echo -n "computing size of $$<..."
	@$(identify) -format '%wx%h\n' '$$<' | head -1 > '$$@' \
	&& echo "done."
endef

%/.exists:
	@mkdir -p $(dir $@) && touch $@

$(foreach i,$(IMG),$(eval $(call IMG_template,$(i))))

all: $(THUMBS) $(SIZES)

clean:
	@echo -n "cleaning thumbnails..."
	@rm -f $(THUMBS) $(SIZES) \
	&& echo "done."

$(imgs_nb:%=%_col.png): %_col.png: %_nb.png Makefile
	$(convert) $< -channel green -fx 'g*g' -channel blue -fx 'b*b' -background 'rgb(255,255,255)' $@

.PHONY: list list2
list2:
	@echo IGNORE=$(IGNORE)
	@echo FORCE=$(FORCE)
list:
	@echo $(IMG)