CC = i686-elf-gcc
INCLUDE = -I./
CFLAGS = -Wall -Wextra -Werror -ffreestanding $(INCLUDE)
LDFLAGS = -T kernel.ld -ffreestanding -O3 -nostdlib -lgcc -mpreferred-stack-boundary=4

BUILDDIR = build

KERNELSRC := $(shell find . -name '*.c' -o -name '*.asm')
KERNELOBJ := $(addprefix $(BUILDDIR)/, \
			 $(notdir \
			 $(patsubst %.c,%.o,\
			 $(patsubst %.asm,%.o,$(KERNELSRC)))))

LIBSRC 	  := $(shell find ./lib -name '*.c')
LIBOBJ    := $(addprefix $(BUILDDIR)/, \
			 $(notdir \
			 $(patsubst %.c,%.o,$(LIBSRC))))

KERNELIMG := $(BUILDDIR)/kernel.bin

QEMUFLAGS = -d int -s \
			-kernel $(KERNELIMG)

.PHONY: all kernel qemu clean docs

all: qemu

qemu: kernel

kernel: $(KERNELIMG)

$(KERNELIMG): $(KERNELOBJ) $(LIBOBJ)
	$(CC) $^ -o $@ $(LDFLAGS)
$(BUILDDIR)/%.o: %.c
	$(CC) $(CFLAGS) -c $^ -o $@ 
$(BUILDDIR)/%.o: %.asm
	nasm -felf32 $^ -o $@

qemu: kernel
	qemu-system-i386 $(QEMUFLAGS)

iso: kernel
	cp $(BUILDDIR)/kernel.bin iso/boot/kernel.bin
	grub-mkrescue -o  $(BUILDDIR)/andewOS.iso iso/

clean:
	rm -rf build/*.o build/*.bin iso/boot/*.bin
docs:
	doxygen