NAME = os

CC = i686-elf-gcc
ASM = i686-elf-as
CFLAGS = -std=gnu99 -ffreestanding -O2 -Wall -Wextra -g
LFLAGS = -ffreestanding -O2 -nostdlib -lgcc -g

SDIR = src
ODIR = obj
SRC = $(wildcard $(SDIR)/*.c)
OBJ = $(patsubst $(SDIR)/%.c,$(ODIR)/%.o,$(SRC))

ASMODIR = asm_obj
ASMSRC = $(wildcard $(SDIR)/*.s)
ASMOBJ = $(patsubst $(SDIR)/%.s,$(ASMODIR)/%.o,$(ASMSRC))

default: kernel.bin

kernel.bin: $(OBJ) $(ASMOBJ)
	$(CC) -T linker.ld -o $@ $^ $(LFLAGS)

$(ODIR)/%.o: $(SDIR)/%.c $(ODIR)
	$(CC) $(CFLAGS) -c -o $@ $<

$(ASMODIR)/%.o: $(SDIR)/%.s $(ASMODIR)
	$(ASM) -g -c -o $@ $<

$(NAME).iso: kernel.bin
	mkdir -p isodir/boot/grub
	cp $< isodir/boot/
	cp grub.cfg isodir/boot/grub/grub.cfg
	grub-mkrescue -o $@ isodir

.PHONY: test debug
test: os.iso
	qemu-system-i386 -cdrom os.iso

debug: kernel.bin
	qemu-system-i386 -s -S -kernel kernel.bin

$(ODIR):
	mkdir -p $@

$(ASMODIR):
	mkdir -p $@

.PHONY: clean

clean: 
	rm -rf $(ODIR)
	rm -rf $(ASMODIR)
	rm -f boot.o
	rm -rf isodir
	rm -f $(NAME).iso