###CONFIGURATION
ARCH    := i686
CROSS   := $(ARCH)-elf-
AS      := $(CROSS)as
CC      := $(CROSS)gcc
LD      := $(CROSS)ld
QEMU	:= qemu-system-i386


CFLAGS  := -ffreestanding -nostdlib -lgcc -g
LDFLAGS := -T linker.ld -nostdlib

SRC_DIR := src
OBJ_DIR := obj
BIN_DIR := build
LOADER_DIR := module_bootloader

SOURCES := $(wildcard $(SRC_DIR)/*.c) $(wildcard $(SRC_DIR)/*.s)
OBJECTS := $(patsubst $(SRC_DIR)/%, $(OBJ_DIR)/%, $(SOURCES:.c=.o))
OBJECTS := $(OBJECTS:.s=.o)


OUT_ELF := $(BIN_DIR)/ukern.elf
OUT_ISO := $(BIN_DIR)/uOS.iso

###RULES

.PHONY: all
all: $(OUT_ELF)

#Build Targets
$(OUT_ELF): $(OBJECTS)
	@mkdir -p $(BIN_DIR)
	$(LD) $(LDFLAGS) -o $@ $^ $(shell $(CC) -print-libgcc-file-name)

$(OBJ_DIR)/%.o: $(SRC_DIR)/%.c
	@mkdir -p $(dir $@)
	$(CC) $(CFLAGS) -c $< -o $@

$(OBJ_DIR)/%.o: $(SRC_DIR)/%.s
	@mkdir -p $(dir $@)
	$(AS) $< -o $@

#Related targets


$(OUT_ISO): $(OUT_ELF)
	@cp $(OUT_ELF) $(LOADER_DIR)/src/boot/
	@$(MAKE) -C $(LOADER_DIR) all
	@cp $(LOADER_DIR)/$(OUT_ISO) $(BIN_DIR)/

#Utility
.PHONY: clean
clean:
	rm -rf $(OBJ_DIR) $(BIN_DIR)

.PHONY: iso
iso: $(OUT_ISO)

.PHONY: run
run:
	$(QEMU) -kernel $(OUT_ELF)

.PHONY: run_iso
run_iso:
	$(QEMU) -cdrom $(OUT_ISO)