PROJECT_BASE ?= $(shell pwd)
ARCH?=x86

O ?= $(PROJECT_BASE)/outdir
# Turn O into an absolute path; we call the main Kbuild with $(MAKE) -C
# which changes the working directory, relative paths don't work right.
# Need to create the directory first to make readlink happy
$(shell mkdir -p $(O))
override O := $(shell readlink -f $(O))

export ARCH MDEF_FILE QEMU_EXTRA_FLAGS PROJECT_BASE

ifdef PLATFORM_CONFIG
ifndef KERNEL_TYPE
$(error KERNEL_TYPE is not defined!  Set it to either micro or nano)
endif
KBUILD_DEFCONFIG=$(KERNEL_TYPE)_$(PLATFORM_CONFIG)_defconfig
export KBUILD_DEFCONFIG
endif

ifdef KBUILD_DEFCONFIG
CONFIG_DEPS=$(O)/.initconfig
else
CONFIG_DEPS=FORCE
endif

SOURCE_DIR ?= $(PROJECT_BASE)/src/
# Kbuild doesn't work correctly if this is an absolute path
override SOURCE_DIR := $(shell python -c "import os.path; print(\"%s\" % os.path.relpath(os.path.realpath('$(SOURCE_DIR)'), os.path.realpath('$(ZEPHYR_BASE)')))")/
export SOURCE_DIR

CONFIG_SHELL := $(shell if [ -x "$$BASH" ]; then echo $$BASH; \
	  else if [ -x /bin/bash ]; then echo /bin/bash; \
	  else echo sh; fi ; fi)

ifeq ("$(origin V)", "command line")
  KBUILD_VERBOSE = $(V)
endif
ifndef KBUILD_VERBOSE
  KBUILD_VERBOSE = 0
endif

ifeq ($(KBUILD_VERBOSE),1)
  Q =
  S =
else
  Q = @
  S = -s
endif

all: $(CONFIG_DEPS) $(O)/.dir
	$(Q)$(MAKE) -C $(ZEPHYR_BASE)  O=$(O) \
		PROJECT=$(PROJECT_BASE) SOURCE_DIR=$(SOURCE_DIR) \
		CFLAGS=$(CFLAGS)

rm-files:= .config
rm-objects:= *.o
rm-dirs := $(O)

cmd_clean_inner_files = \
	$(shell cd $(PROJECT_BASE);rm $(rm-files) -f; rm $(rm-dirs) -rf)

clean: FORCE
	$(Q)rm $(SOURCE_DIR)$(rm-objects) -f
	$(Q)rm $(SOURCE_DIR)/modules.order -f
	$(Q)rm $(SOURCE_DIR)/.*.cmd -f
	$(call cmd_clean_inner_files)

pristine: distclean

distclean: clean
	@rm $(PROJECT_BASE)/.config -f
	@rm $(PROJECT_BASE)/.config.old -f
	@rm $(PROJECT_BASE)/.version -f

mrproper: FORCE
	$(call cmd_clean_inner_files)
	$(Q)$(MAKE) -C $(ZEPHYR_BASE) PROJECT=$(PROJECT_BASE) mrproper

%config: $(O)/.dir FORCE
	$(Q)$(MAKE) $(S) -C $(ZEPHYR_BASE) O=$(O) PROJECT=$(PROJECT_BASE) $@

qemu: $(CONFIG_DEPS) $(O)/.dir
	$(Q)$(MAKE) -C $(ZEPHYR_BASE) O=$(O) \
		PROJECT=$(PROJECT_BASE) SOURCE_DIR=$(SOURCE_DIR) \
		CFLAGS=$(CFLAGS) qemu


$(O)/.config: $(O)/.dir
	$(Q)cp $(ZEPHYR_BASE)/arch/$(ARCH)/configs/$(KBUILD_DEFCONFIG) \
		$(O)/.config

$(O)/.initconfig: mergeconfig
	$(Q)yes "" | $(MAKE) $(S) -C $(ZEPHYR_BASE) O=$(O) \
		PROJECT=$(PROJECT_BASE) oldconfig
	touch $@

ifneq (($strip $(CONF_FILE)),)
mergeconfig: $(O)/.config $(CONF_FILE)
	$(Q)$(CONFIG_SHELL) $(ZEPHYR_BASE)/scripts/kconfig/merge_config.sh \
		-q -m -O $(O) $(O)/.config $(CONF_FILE)
else
mergeconfig: defconfig $(CONF_FILE);
endif

$(CONF_FILE):;

%/.dir:
	$(Q)set -e;
	$(Q)test -s $(abspath $(dir $@)) || mkdir $(abspath $(dir $@)) -p
	$(Q)touch $@

help:
	$(Q)$(MAKE) -C $(ZEPHYR_BASE) help

PHONY += FORCE clean mrproper
FORCE:

.PHONY: $(PHONY)
.PRECIOUS: %/.dir