PACKAGE    = $(notdir $(realpath .))
FOMU_SDK  ?= .
ADD_CFLAGS = -I$(FOMU_SDK)/include -D__vexriscv__ -march=rv32im  -mabi=ilp32
ADD_LFLAGS = -L$(FOMU_SDK)/lib $(FOMU_SDK)/lib/crt0-vexriscv-ctr.o -lbase-nofloat -lcompiler_rt
SRC_DIR    = src

GIT_VERSION= $(shell git describe --tags)
TRGT      ?= riscv64-unknown-elf-
CC         = $(TRGT)gcc
CXX        = $(TRGT)g++
OBJCOPY    = $(TRGT)objcopy

RM         = rm -rf
COPY       = cp -a
PATH_SEP   = /

ifeq ($(OS),Windows_NT)
COPY       = copy
RM         = del
PATH_SEP   = \\
endif

LDSCRIPT   = $(FOMU_SDK)/ld/linker.ld
LDSCRIPTS   = $(LDSCRIPT) $(FOMU_SDK)/ld/output_format.ld $(FOMU_SDK)/ld/regions.ld
DBG_CFLAGS = -ggdb -g -DDEBUG -Wall
DBG_LFLAGS = -ggdb -g -Wall
CFLAGS     = $(ADD_CFLAGS) \
             -Wall -Wextra \
             -ffunction-sections -fdata-sections -fno-common \
             -fomit-frame-pointer -Os \
			 -flto -ffreestanding -fuse-linker-plugin \
             -DGIT_VERSION=u\"$(GIT_VERSION)\" -std=gnu11
CXXFLAGS   = $(CFLAGS) -std=c++11 -fno-rtti -fno-exceptions
LFLAGS     = $(CFLAGS) $(ADD_LFLAGS) \
             -nostartfiles \
             -Wl,--gc-sections \
             -Wl,--no-warn-mismatch \
			 -Wl,--script=$(LDSCRIPT) \
			 -Wl,--build-id=none

OBJ_DIR    = .obj

CSOURCES   = $(wildcard $(SRC_DIR)/*.c)
CPPSOURCES = $(wildcard $(SRC_DIR)/*.cpp)
ASOURCES   = $(wildcard $(SRC_DIR)/*.S)
COBJS      = $(addprefix $(OBJ_DIR)/, $(notdir $(CSOURCES:.c=.o)))
CXXOBJS    = $(addprefix $(OBJ_DIR)/, $(notdir $(CPPSOURCES:.cpp=.o)))
AOBJS      = $(addprefix $(OBJ_DIR)/, $(notdir $(ASOURCES:.S=.o)))
OBJECTS    = $(COBJS) $(CXXOBJS) $(AOBJS)
VPATH      = $(SRC_DIR)

QUIET      = @

ALL        = all
TARGET     = $(PACKAGE).elf
CLEAN      = clean

$(ALL): $(TARGET) $(PACKAGE).bin $(PACKAGE).ihex $(PACKAGE).dfu

$(OBJECTS): | $(OBJ_DIR)

$(TARGET): $(OBJECTS) $(LDSCRIPTS)
	$(QUIET) echo "  LD       $@"
	$(QUIET) $(CXX) $(OBJECTS) $(LFLAGS) -o $@

$(PACKAGE).bin: $(TARGET)
	$(QUIET) echo "  OBJCOPY  $@"
	$(QUIET) $(OBJCOPY) -O binary $(TARGET) $@

$(PACKAGE).dfu: $(TARGET)
	$(QUIET) echo "  DFU      $@"
	$(QUIET) $(COPY) $(PACKAGE).bin $@
	$(QUIET) dfu-suffix -v 1209 -p 70b1 -a $@

$(PACKAGE).ihex: $(TARGET)
	$(QUIET) echo "  IHEX     $(PACKAGE).ihex"
	$(QUIET) $(OBJCOPY) -O ihex $(TARGET) $@

$(DEBUG): CFLAGS += $(DBG_CFLAGS)
$(DEBUG): LFLAGS += $(DBG_LFLAGS)
CFLAGS += $(DBG_CFLAGS)
LFLAGS += $(DBG_LFLAGS)
$(DEBUG): $(TARGET)

$(OBJ_DIR):
	$(QUIET) mkdir $(OBJ_DIR)

$(COBJS) : $(OBJ_DIR)/%.o : %.c Makefile
	$(QUIET) echo "  CC       $<	$(notdir $@)"
	$(QUIET) $(CC) -c $< $(CFLAGS) -o $@ -MMD

$(OBJ_DIR)/%.o: %.cpp
	$(QUIET) echo "  CXX      $<	$(notdir $@)"
	$(QUIET) $(CXX) -c $< $(CXXFLAGS) -o $@ -MMD

$(OBJ_DIR)/%.o: %.S
	$(QUIET) echo "  AS       $<	$(notdir $@)"
	$(QUIET) $(CC) -x assembler-with-cpp -c $< $(CFLAGS) -o $@ -MMD

.PHONY: clean

clean:
	$(QUIET) echo "  RM      $(subst /,$(PATH_SEP),$(wildcard $(OBJ_DIR)/*.d))"
	-$(QUIET) $(RM) $(subst /,$(PATH_SEP),$(wildcard $(OBJ_DIR)/*.d))
	$(QUIET) echo "  RM      $(subst /,$(PATH_SEP),$(wildcard $(OBJ_DIR)/*.d))"
	-$(QUIET) $(RM) $(subst /,$(PATH_SEP),$(wildcard $(OBJ_DIR)/*.o))
	$(QUIET) echo "  RM      $(TARGET) $(PACKAGE).bin $(PACKAGE).symbol $(PACKAGE).ihex $(PACKAGE).dfu"
	-$(QUIET) $(RM) $(TARGET) $(PACKAGE).bin $(PACKAGE).symbol $(PACKAGE).ihex $(PACKAGE).dfu

include $(wildcard $(OBJ_DIR)/*.d)