VERSION=0.0.2
SYSLINUX_VERSION=6.03
KERNEL_VERSION=6.1.11
TARGET=./target
INITRAMFS=${TARGET}/initramfs
ROOTFS=${TARGET}/rootfs
ISO=${TARGET}/rex.iso

default_target: iso

core: lib
	@echo Building Core
	@$(MAKE) -C core/

lib:
	@echo Building Lib
	@$(MAKE) -C lib/

smash: lib
	@echo Building Smash
	@$(MAKE) -C smash/

dist:
	@echo Extracting Dist
	@mkdir -p dist/core dist/smash
	@cp core/objects/* dist/core/
	@cp smash/smash dist/smash/
	@cp lib/slib.a dist/

target:
	@echo Creating Target Directory
	@mkdir target


initramfs: target core smash
	@echo Installing Initramfs
	@mkdir -p ${INITRAMFS}/bin ${INITRAMFS}/etc ${INITRAMFS}/shr/man
	@cp core/objects/* ${INITRAMFS}/bin/
	@cp man/* ${INITRAMFS}/shr/man/
	@cp smash/smash ${INITRAMFS}/bin/
	@cp utils/* ${INITRAMFS}/bin/
	@cp etc/* ${INITRAMFS}/etc/
	@mv ${INITRAMFS}/bin/init ${INITRAMFS}/init
	@echo Building Initramfs
	@cd ${INITRAMFS} && find . | cpio -o --quiet --format=newc > ../initramfs.img

${TARGET}/kernel:
	@echo Downloading Kernel
	@curl -s "https://cdn.kernel.org/pub/linux/kernel/v6.x/linux-${KERNEL_VERSION}.tar.xz" -o ${TARGET}/kernel.tar.gz
	@echo Extracting Kernel
	@tar -xf ${TARGET}/kernel.tar.gz
	@mv linux-${KERNEL_VERSION} ${TARGET}/kernel-src
	@cp config/linux.config ${TARGET}/kernel-src/.config
	@echo Building Kernel
	@$(MAKE) -C ${TARGET}/kernel-src > /dev/null
	@cp ${TARGET}/kernel-src/arch/x86_64/boot/bzImage ${TARGET}/kernel

${TARGET}/syslinux:
	@echo Downloading SYSLINUX
	@curl -s "https://mirrors.edge.kernel.org/pub/linux/utils/boot/syslinux/syslinux-${SYSLINUX_VERSION}.tar.gz" -o ${TARGET}/syslinux.tar.gz
	@echo Extracting SYSLINUX
	@tar -xf ${TARGET}/syslinux.tar.gz
	@mv syslinux-${SYSLINUX_VERSION} ${TARGET}/syslinux
	

rootfs: target initramfs ${TARGET}/syslinux ${TARGET}/kernel
	@echo Installing Rootfs
	@mkdir -p ${ROOTFS}/syslinux ${ROOTFS}/images/rex/
	@cp ${TARGET}/initramfs.img ${ROOTFS}/images/rex/boot.img
	@cp ${TARGET}/kernel ${ROOTFS}/images/rex/kernel
	@cp config/syslinux.cfg ${ROOTFS}/syslinux/syslinux.cfg
	@cp ${TARGET}/syslinux/bios/core/isolinux.bin \
	         ${TARGET}/syslinux/bios/com32/elflink/ldlinux/ldlinux.c32 \
	         ${TARGET}/syslinux/bios/com32/libutil/libutil.c32 \
	         ${TARGET}/syslinux/bios/com32/menu/menu.c32 \
	         ${ROOTFS}/syslinux/

iso: rootfs
	@echo Creating ISO
	@mkisofs -o ${ISO} \
		-rational-rock \
		-volid "reX ${VERSION}" \
		-cache-inodes \
		-joliet \
		-full-iso9660-filenames \
		-input-charset UTF8 \
		-b syslinux/isolinux.bin \
		-c syslinux/boot.cat \
		-no-emul-boot \
		-boot-load-size 4 \
		-boot-info-table \
		-quiet \
		${ROOTFS}
	@isohybrid ${ISO}
	@echo Building ISO finished.
	@echo
	@echo The ISO is located under ${ISO}
	@echo

qemu: iso
	@echo Running QEMU
	@qemu-system-x86_64 -cdrom ${ISO}

qemu-nographic: iso
	@echo Running QEMU in nongraphic mode
	@echo
	@echo IMPORTANT: Select Serial Mode in the bootloader.
	@echo            Else there will be no output.
	@echo
	@qemu-system-x86_64 -cdrom ${ISO} -nographic

clean:
	@echo Cleaning Up reX Repository
	@-rm -r target
	@$(MAKE) -C core clean
	@$(MAKE) -C lib clean
	@$(MAKE) -C smash clean

.PHONY: core lib smash initramfs rootfs iso qemu qemu-nographic clean