SVG_GENERATE_FORMATS        ?= png svg
SVG                         ?= $(filter-out copied-%,$(wildcard *.svg))
COPIED_SVG                   = $(addprefix copied-,$(notdir $(SVG)))
INKSCAPE_VERSION             = $(shell inkscape -V 2>&1 | sed '/Inkscape/ !d; s/Inkscape *\([0-9.]\+\) .*/\1/')
INKSCAPE_VERSION_MAJOR       = $(word 1,$(subst ., ,$(INKSCAPE_VERSION)))
ifeq ($(INKSCAPE_VERSION_MAJOR),1)
  INKSCAPE_EXPORT_PNG        = --export-filename
else
  INKSCAPE_EXPORT_PNG        = --export-png
endif

GENERATED_ICON_WIDTHS       += 16 32 48 64 72 96 128 144 168 192
GENERATED_WIDTHS            ?= $(GENERATED_ICON_WIDTHS) $(GENERATED_EXTRA_WIDTHS)

ifneq ($(filter png,$(SVG_GENERATE_FORMATS)),)
  GENERATED_WIDTHS_PNG      ?= $(GENERATED_WIDTHS)
  GENERATED_PNG             ?= \
  	$(foreach w, $(GENERATED_WIDTHS_PNG),$(patsubst %.svg,%-$w.png,$(notdir $(SVG))))
  GENERATED_IMAGES          += $(GENERATED_PNG)
endif

ifneq ($(filter ico,$(SVG_GENERATE_FORMATS)),)
  GENERATED_WIDTHS_ICO      ?= 16 32
  GENERATED_ICO             ?= \
  	$(foreach w, $(GENERATED_WIDTHS_ICO),$(patsubst %.svg,%-$w.ico,$(notdir $(SVG))))
  GENERATED_IMAGES          += $(GENERATED_ICO)
endif

ifneq ($(filter pdf,$(SVG_GENERATE_FORMATS)),)
  GENERATED_PDF             ?= $(patsubst %.svg,%.pdf,$(notdir $(SVG)))
  GENERATED_IMAGES          += $(GENERATED_PDF)
endif

ifneq ($(filter svg,$(SVG_GENERATE_FORMATS)),)
  IMAGES                    += $(notdir $(SVG))
endif

all: $(GENERATED_IMAGES)
install:
clean: clean.images
distclean:

clean.images:
	$(RM) -f $(GENERATED_IMAGES) $(COPIED_SVG)

%.png: $(COPIED_SVG)
	inkscape -w $(shell echo $* | sed 's/.*-//') \
		$(INKSCAPE_EXPORT_PNG)=$@ copied-$(shell echo $* | sed 's/-[0-9]\+$$//').svg

%.pdf: copied-%.svg
	inkscape --export-filename="$@" $<

copied-%.svg: $(SVG)
	@echo $^
	cp $(filter %$*.svg, $^) $@.tmp
	mv $@.tmp $@

%.ico: %.png
	icotool -o $@ -c $<