ifeq (, $(__RIOTBUILD_FLAG))
  $(error You cannot build a module on its own. Use "make" in your application's directory instead.)
endif

#
# enable second expansion of prerequisites.
#
# Doing that here enables it globally for all modules and the application.
#
# See https://www.gnu.org/software/make/manual/html_node/Secondary-Expansion.html
# for what it can be used for.
.SECONDEXPANSION:

unexport DIRS
DIRS := $(sort $(abspath $(DIRS)))

_MOD := $(shell basename $(CURDIR))
MODULE ?= $(_MOD)

.PHONY: all clean $(DIRS:%=ALL--%) $(DIRS:%=CLEAN--%) $(MODULE).module

all: $(MODULE).module ..nothing

..nothing:
	@:

clean:: $(DIRS:%=CLEAN--%)

$(DIRS:%=ALL--%):
	$(QQ)"$(MAKE)" -C $(@:ALL--%=%)

$(DIRS:%=CLEAN--%):
	$(QQ)"$(MAKE)" -C $(@:CLEAN--%=%) clean

## submodules
ifeq (1, $(SUBMODULES))
  # don't use *.c as SRC if SRC is empty (e.g., no module selected)
  NO_AUTO_SRC := 1

  # allow different submodule basename (e.g., MODULE=cpu_periph_common, but match just periph_%)
  BASE_MODULE ?= $(MODULE)

  # for each $(BASE_MODULE)_<name> in USEMODULE, add <name>.c to SRC
  SRC += $(wildcard $(patsubst $(BASE_MODULE)_%,%.c,$(filter $(BASE_MODULE)_%,$(USEMODULE))))

  # remove duplicates
  SRC := $(sort $(SRC))
endif

# By default consider C++ files has a .cpp extension
SRCXXEXT ?= cpp

ifeq ($(strip $(SRC))$(NO_AUTO_SRC),)
  SRC := $(filter-out $(SRC_NOLTO), $(wildcard *.c))
endif
ifeq ($(strip $(SRCXX))$(NO_AUTO_SRC),)
  SRCXX := $(filter-out $(SRCXXEXCLUDE),$(wildcard *.$(SRCXXEXT)))
endif
ifeq ($(strip $(ASMSRC))$(NO_AUTO_SRC),)
  ASMSRC := $(wildcard *.s)
endif
ifeq ($(strip $(ASSMSRC))$(NO_AUTO_SRC),)
  ASSMSRC := $(wildcard *.S)
endif

ifneq (,$(SRCXX))
  ifeq (,$(filter cpp,$(FEATURES_USED)))
    $(error Found C++ source, but feature "cpp" is not used. Add "FEATURES_REQUIRED += cpp")
  endif
endif

# include makefile snippets for packages in $(USEPKG) that modify GENSRC:
-include $(USEPKG:%=$(RIOTPKG)/%/Makefile.gensrc)

GENOBJC     := $(GENSRC:%.c=%.o)
OBJC_LTO    := $(SRC:%.c=$(BINDIR)/$(MODULE)/%.o)
OBJC_NOLTO  := $(SRC_NOLTO:%.c=$(BINDIR)/$(MODULE)/%.o)
OBJC        := $(OBJC_NOLTO) $(OBJC_LTO)
OBJCXX      := $(SRCXX:%.$(SRCXXEXT)=$(BINDIR)/$(MODULE)/%.o)
ASMOBJ      := $(ASMSRC:%.s=$(BINDIR)/$(MODULE)/%.o)
ASSMOBJ     := $(ASSMSRC:%.S=$(BINDIR)/$(MODULE)/%.o)

OBJ := $(OBJC) $(OBJCXX) $(ASMOBJ) $(ASSMOBJ) $(GENOBJC)
DEP := $(OBJC:.o=.d) $(OBJCXX:.o=.d) $(ASSMOBJ:.o=.d)

include $(RIOTMAKE)/blob.inc.mk
include $(RIOTMAKE)/tools/fixdep.inc.mk

$(BINDIR)/$(MODULE)/:
	$(Q)mkdir -p $@

$(MODULE).module $(OBJ): | $(BINDIR)/$(MODULE)/

$(MODULE).module: $(OBJ) | $(DIRS:%=ALL--%)

CXXFLAGS = $(filter-out $(CXXUWFLAGS), $(CFLAGS)) $(CXXEXFLAGS)
CCASFLAGS = $(filter-out $(CCASUWFLAGS), $(CFLAGS)) $(CCASEXFLAGS)

# compile and generate dependency info

$(OBJC_LTO): CFLAGS+=$(LTOFLAGS)

# Define dependencies for object files
OBJ_DEPS += $(RIOTBUILD_CONFIG_HEADER_C)

$(OBJC): $(BINDIR)/$(MODULE)/%.o: %.c $(OBJ_DEPS) | $(if $(SHOULD_RUN_KCONFIG),$(KCONFIG_GENERATED_AUTOCONF_HEADER_C))
	$(Q)$(CCACHE) $(CC) \
		-DRIOT_FILE_RELATIVE=\"$(patsubst $(RIOTBASE)/%,%,$(abspath $<))\" \
		-DRIOT_FILE_NOPATH=\"$(notdir $<)\" \
		$(CFLAGS) $(INCLUDES) -MQ '$@' -MD -MP -c -o $@ $(abspath $<)
ifneq (,$(SHOULD_RUN_KCONFIG))
	$(Q)$(FIXDEP) $(@:.o=.d) $@ $(KCONFIG_SYNC_DIR) > $(@:.o=.tmp)
	$(Q)mv $(@:.o=.tmp) $(@:.o=.d)
endif

$(GENOBJC): %.o: %.c $(OBJ_DEPS) | $(if $(SHOULD_RUN_KCONFIG),$(KCONFIG_GENERATED_AUTOCONF_HEADER_C))
	$(Q) $(CCACHE) $(CC) \
		-DRIOT_FILE_RELATIVE=\"$(patsubst $(RIOTBASE)/%,%,$<)\" \
		-DRIOT_FILE_NOPATH=\"$(notdir $<)\" \
		$(CFLAGS) $(INCLUDES) -MQ '$@' -MD -MP -c -o $@ $<
ifneq (,$(SHOULD_RUN_KCONFIG))
	$(Q)$(FIXDEP) $(@:.o=.d) $@ $(KCONFIG_SYNC_DIR) > $(@:.o=.tmp)
	$(Q)mv $(@:.o=.tmp) $(@:.o=.d)
endif

$(OBJCXX): $(BINDIR)/$(MODULE)/%.o: %.$(SRCXXEXT) $(OBJ_DEPS) | $(if $(SHOULD_RUN_KCONFIG),$(KCONFIG_GENERATED_AUTOCONF_HEADER_C))
	$(Q)$(CCACHE) $(CXX) \
		-DRIOT_FILE_RELATIVE=\"$(patsubst $(RIOTBASE)/%,%,$(abspath $<))\" \
		-DRIOT_FILE_NOPATH=\"$(notdir $<)\" \
		$(CXXFLAGS) $(CXXINCLUDES) $(INCLUDES) -MQ '$@' -MD -MP -c -o $@ $(abspath $<)
ifneq (,$(SHOULD_RUN_KCONFIG))
	$(Q)$(FIXDEP) $(@:.o=.d) $@ $(KCONFIG_SYNC_DIR) > $(@:.o=.tmp)
	$(Q)mv $(@:.o=.tmp) $(@:.o=.d)
endif

$(ASMOBJ): $(BINDIR)/$(MODULE)/%.o: %.s
	$(Q)$(AS) $(ASFLAGS) -o $@ $(abspath $<)

$(ASSMOBJ): $(BINDIR)/$(MODULE)/%.o: %.S $(OBJ_DEPS) | $(if $(SHOULD_RUN_KCONFIG),$(KCONFIG_GENERATED_AUTOCONF_HEADER_C))
	$(Q)$(CCAS) $(CCASFLAGS) $(INCLUDES) -MQ '$@' -MD -MP -c -o $@ $(abspath $<)
ifneq (,$(SHOULD_RUN_KCONFIG))
	$(Q)$(FIXDEP) $(@:.o=.d) $@ $(KCONFIG_SYNC_DIR) > $(@:.o=.tmp)
	$(Q)mv $(@:.o=.tmp) $(@:.o=.d)
endif

# pull in dependency info for *existing* .o files
# deleted header files will be silently ignored
-include $(DEP)