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
#
# 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 \
        compile-commands $(DIRS:%=COMPILE-COMMANDS--%) $(MODULE).cleanup

all: $(MODULE).module ..nothing

..nothing:
	@:

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

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

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

$(DIRS:%=COMPILE-COMMANDS--%):
	$(QQ)"$(MAKE)" -C $(@:COMPILE-COMMANDS--%=%) compile-commands

## 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
  # unless in SUBMODULES_NO_SRC
  SRC += $(wildcard \
            $(filter-out $(SUBMODULES_NO_SRC),\
                $(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,$(USEMODULE)))
    $(error Found C++ source, but feature "cpp" is not used. Add "FEATURES_REQUIRED += cpp")
  endif
endif

compile-commands: | $(DIRS:%=COMPILE-COMMANDS--%)
	$(file >$(BINDIR)/$(MODULE)/compile_cmds.txt,SRC: $(sort $(SRC) $(SRC_NO_LTO)))
	$(file >>$(BINDIR)/$(MODULE)/compile_cmds.txt,SRC_NO_LTO: $(sort $(SRC_NO_LTO)))
	$(file >>$(BINDIR)/$(MODULE)/compile_cmds.txt,SRCXX: $(sort $(SRCXX)))
	$(file >>$(BINDIR)/$(MODULE)/compile_cmds.txt,CURDIR: $(CURDIR))
	$(file >>$(BINDIR)/$(MODULE)/compile_cmds.txt,CFLAGS: $(CFLAGS))
	$(file >>$(BINDIR)/$(MODULE)/compile_cmds.txt,LTOFLAGS: $(LTOFLAGS))
	$(file >>$(BINDIR)/$(MODULE)/compile_cmds.txt,INCLUDES: $(INCLUDES))
	$(file >>$(BINDIR)/$(MODULE)/compile_cmds.txt,CXXFLAGS: $(CXXFLAGS))
	$(file >>$(BINDIR)/$(MODULE)/compile_cmds.txt,CXXINCLUDES: $(CXXINCLUDES))
	$(file >>$(BINDIR)/$(MODULE)/compile_cmds.txt,CC: $(CC))
	$(file >>$(BINDIR)/$(MODULE)/compile_cmds.txt,CXX: $(CXX))
	$(file >>$(BINDIR)/$(MODULE)/compile_cmds.txt,TARGET_ARCH: $(TARGET_ARCH))
	$(file >>$(BINDIR)/$(MODULE)/compile_cmds.txt,TARGET_ARCH_LLVM: $(TARGET_ARCH_LLVM))

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)

SRC_ALL := $(SRC) $(SRCXX) $(ASMSRC) $(ASSMSRC)
SUBDIRS_IN_DIRS := $(filter $(DIRS), $(abspath $(sort $(dir $(SRC_ALL)))))
ifneq (,$(SUBDIRS_IN_DIRS))
  $(warning Files of the following subdirectories are selected \
    both as RIOT modules (using DIRS) and directly as sourcefiles (using SRC): \
    $(patsubst $(CURDIR)/%,./%, $(SUBDIRS_IN_DIRS)). \
    Please select a single approach for each subfolder to prevent linking errors.)
endif
SUBDIRS := $(filter-out $(BINDIR)/$(MODULE)/, $(dir $(OBJ)))

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

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

OLD_OBJECTS = $(wildcard $(BINDIR)/$(MODULE)/*.o $(BINDIR)/$(MODULE)/**/*.o)

# do not clean objects from bindist modules
ifeq (,$(filter $(MODULE),$(BIN_USEMODULE)))
  OBJECTS_TO_REMOVE = $(filter-out $(OBJ),$(OLD_OBJECTS))
endif

$(MODULE).module compile-commands $(OBJ): | $(BINDIR)/$(MODULE)/ $(SUBDIRS)

$(MODULE).module: $(OBJ) $(if $(OBJECTS_TO_REMOVE),$(MODULE).cleanup) | $(DIRS:%=ALL--%)

$(MODULE).cleanup:
	$(Q)# cleanup non selected source files objects
	$(Q)$(RM) $(OBJECTS_TO_REMOVE)

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)