ifeq ($(TOOLCHAIN),)
  ifeq ($(shell util/check.sh),y)
    export PATH := $(shell util/activate.sh)
  else
    FOO := $(shell util/prompt.sh)
    ifeq ($(shell util/check.sh),y)
      export PATH := $(shell util/activate.sh)
    else
      $(error "No toolchain, and you did not ask to build it.")
    endif
  endif
endif

# Prevents Make from removing intermediary files on failure
.SECONDARY:

# Disable built-in rules
.SUFFIXES:

TARGET_TRIPLET=i686-pc-toaru

# Userspace flags

CC=$(TARGET_TRIPLET)-gcc
AR=$(TARGET_TRIPLET)-ar
AS=$(TARGET_TRIPLET)-as
CFLAGS= -O3 -g -std=gnu99 -I. -Iapps -pipe -mmmx -msse -msse2 -fplan9-extensions -Wall -Wextra -Wno-unused-parameter

LIBC_OBJS  = $(patsubst %.c,%.o,$(wildcard libc/*.c))
LIBC_OBJS += $(patsubst %.c,%.o,$(wildcard libc/*/*.c))
LIBC_OBJS += libc/setjmp.o
LC=base/lib/libc.so

APPS=$(patsubst apps/%.c,%,$(wildcard apps/*.c))
APPS_X=$(foreach app,$(APPS),base/bin/$(app))
APPS_Y=$(foreach app,$(filter-out init,$(APPS)),.make/$(app).mak)

LIBS=$(patsubst lib/%.c,%,$(wildcard lib/*.c))
LIBS_X=$(foreach lib,$(LIBS),base/lib/libtoaru_$(lib).so)
LIBS_Y=$(foreach lib,$(LIBS),.make/$(lib).lmak)

all: image.iso

# Kernel / module flags

KCC = $(TARGET_TRIPLET)-gcc
KAS = $(TARGET_TRIPLET)-as
KLD = $(TARGET_TRIPLET)-ld
KNM = $(TARGET_TRIPLET)-nm

KCFLAGS  = -O2 -std=c99
KCFLAGS += -finline-functions -ffreestanding
KCFLAGS += -Wall -Wextra -Wno-unused-function -Wno-unused-parameter -Wno-format
KCFLAGS += -pedantic -fno-omit-frame-pointer
KCFLAGS += -D_KERNEL_
KCFLAGS += -DKERNEL_GIT_TAG=$(shell util/make-version)
KASFLAGS = --32

KERNEL_OBJS = $(patsubst %.c,%.o,$(wildcard kernel/*.c))
KERNEL_OBJS += $(patsubst %.c,%.o,$(wildcard kernel/*/*.c))
KERNEL_OBJS += $(patsubst %.c,%.o,$(wildcard kernel/*/*/*.c))

KERNEL_ASMOBJS = $(filter-out kernel/symbols.o,$(patsubst %.S,%.o,$(wildcard kernel/*.S)))

# Kernel

fatbase/kernel: ${KERNEL_ASMOBJS} ${KERNEL_OBJS} kernel/symbols.o
	${KCC} -T kernel/link.ld ${KCFLAGS} -nostdlib -o $@ ${KERNEL_ASMOBJS} ${KERNEL_OBJS} kernel/symbols.o -lgcc

kernel/symbols.o: ${KERNEL_ASMOBJS} ${KERNEL_OBJS} util/generate_symbols.py
	-rm -f kernel/symbols.o
	${KCC} -T kernel/link.ld ${KCFLAGS} -nostdlib -o .toaruos-kernel ${KERNEL_ASMOBJS} ${KERNEL_OBJS} -lgcc
	${KNM} .toaruos-kernel -g | util/generate_symbols.py > kernel/symbols.S
	${KAS} ${KASFLAGS} kernel/symbols.S -o $@
	-rm -f .toaruos-kernel

kernel/sys/version.o: kernel/*/*.c kernel/*.c

kernel/%.o: kernel/%.S
	${KAS} ${ASFLAGS} $< -o $@

kernel/%.o: kernel/%.c ${HEADERS}
	${KCC} ${KCFLAGS} -nostdlib -g -c -o $@ $<

# Modules

fatbase/mod:
	@mkdir -p $@

MODULES = $(patsubst modules/%.c,fatbase/mod/%.ko,$(wildcard modules/*.c))

HEADERS = $(shell find base/usr/include/kernel -type f -name '*.h')

fatbase/mod/%.ko: modules/%.c ${HEADERS} | fatbase/mod
	${KCC} -T modules/link.ld -nostdlib ${KCFLAGS} -c -o $@ $<

modules: ${MODULES}

# Root Filesystem

base/dev:
	mkdir -p $@
base/tmp:
	mkdir -p $@
base/proc:
	mkdir -p $@
base/bin:
	mkdir -p $@
base/lib:
	mkdir -p $@
fatbase/efi/boot:
	mkdir -p $@
.make:
	mkdir -p .make
dirs: base/dev base/tmp base/proc base/bin base/lib fatbase/efi/boot .make

# C Library

crts: base/lib/crt0.o base/lib/crti.o base/lib/crtn.o | dirs

base/lib/crt%.o: libc/crt%.s
	yasm -f elf -o $@ $<

libc/setjmp.o: libc/setjmp.S
	$(AS) -o $@ $<

libc/%.o: libc/%.c
	$(CC) $(CFLAGS) -fPIC -c -o $@ $<

base/lib/libc.a: ${LIBC_OBJS} | dirs crts
	$(AR) cr $@ $^

base/lib/libc.so: ${LIBC_OBJS} | dirs crts
	$(CC) -nodefaultlibs -o $@ $(CFLAGS) -shared -fPIC $^ -lgcc

base/lib/libm.so: util/lm.c | dirs crts
	$(CC) -nodefaultlibs -o $@ $(CFLAGS) -shared -fPIC $^ -lgcc

# Userspace Linker/Loader

base/lib/ld.so: linker/linker.c base/lib/libc.a | dirs
	$(CC) -static -Wl,-static $(CFLAGS) -o $@ -Os -T linker/link.ld $<

# Shared Libraries
.make/%.lmak: lib/%.c util/auto-dep.py | dirs
	util/auto-dep.py --makelib $< > $@

ifeq (,$(findstring clean,$(MAKECMDGOALS)))
-include ${LIBS_Y}
endif

# Init (static)

base/bin/init: apps/init.c base/lib/libc.a | dirs
	$(CC) -static -Wl,-static $(CFLAGS) -o $@ $<

fatbase/netinit: util/netinit.c base/lib/libc.a | dirs
	$(CC) -s -static -Wl,-static $(CFLAGS) -o $@ $<

# Userspace applications

.make/%.mak: apps/%.c util/auto-dep.py | dirs
	util/auto-dep.py --make $< > $@

ifeq (,$(findstring clean,$(MAKECMDGOALS)))
-include ${APPS_Y}
endif

# Ramdisk

fatbase/ramdisk.img: ${APPS_X} ${LIBS_X} base/lib/ld.so base/lib/libm.so $(shell find base) Makefile | dirs
	genext2fs -B 4096 -d base -D util/devtable -U -b `util/calc-size.sh` -N 2048 $@

# CD image

ifeq (,$(wildcard /usr/lib32/crt0-efi-ia32.o))
$(error Missing GNU-EFI.)
endif

EFI_XORRISO=-eltorito-alt-boot -e fat.img -no-emul-boot -isohybrid-gpt-basdat
EFI_BOOT=cdrom/fat.img
EFI_UPDATE=util/update-extents.py

image.iso: ${EFI_BOOT} cdrom/boot.sys fatbase/netinit ${MODULES} util/update-extents.py
	xorriso -as mkisofs -R -J -c bootcat \
	  -b boot.sys -no-emul-boot -boot-load-size 24 \
	  ${EFI_XORRISO} \
	  -o image.iso cdrom
	${EFI_UPDATE}

# Boot loader

cdrom/fat.img: fatbase/ramdisk.img ${MODULES} fatbase/kernel fatbase/netinit fatbase/efi/boot/bootia32.efi fatbase/efi/boot/bootx64.efi util/mkdisk.sh
	util/mkdisk.sh $@ fatbase

EFI_CFLAGS=-fno-stack-protector -fpic -DEFI_PLATFORM -ffreestanding -fshort-wchar -I /usr/include/efi -mno-red-zone
EFI_SECTIONS=-j .text -j .sdata -j .data -j .dynamic -j .dynsym -j .rel -j .rela -j .reloc

boot/efi.so: boot/cstuff.c boot/*.h
	$(CC) ${EFI_CFLAGS} -I /usr/include/efi/ia32 -c -o boot/efi.o $<
	$(LD) boot/efi.o /usr/lib32/crt0-efi-ia32.o -nostdlib -znocombreloc -T /usr/lib32/elf_ia32_efi.lds -shared -Bsymbolic -L /usr/lib32 -lefi -lgnuefi -o boot/efi.so

fatbase/efi/boot/bootia32.efi: boot/efi.so
	objcopy ${EFI_SECTIONS} --target=efi-app-ia32 $< $@

boot/efi64.so: boot/cstuff.c boot/*.h
	gcc ${EFI_CFLAGS} -I /usr/include/efi/x86_64 -DEFI_FUNCTION_WRAPPER -c -o boot/efi64.o $<
	$(LD) boot/efi64.o /usr/lib/crt0-efi-x86_64.o -nostdlib -znocombreloc -T /usr/lib/elf_x86_64_efi.lds -shared -Bsymbolic -L /usr/lib -lefi -lgnuefi -o boot/efi64.so

fatbase/efi/boot/bootx64.efi: boot/efi64.so
	objcopy ${EFI_SECTIONS} --target=efi-app-x86_64 $< $@

cdrom/boot.sys: boot/boot.o boot/cstuff.o boot/link.ld | dirs
	${KLD} -T boot/link.ld -o $@ boot/boot.o boot/cstuff.o

boot/cstuff.o: boot/cstuff.c boot/*.h
	${KCC} -c -Os -o $@ $<

boot/boot.o: boot/boot.s
	yasm -f elf -o $@ $<

.PHONY: clean
clean:
	rm -f base/lib/*.so
	rm -f base/lib/libc.a
	rm -f ${APPS_X}
	rm -f libc/*.o libc/*/*.o
	rm -f image.iso
	rm -f fatbase/ramdisk.img
	rm -f cdrom/boot.sys
	rm -f boot/*.o
	rm -f boot/*.efi
	rm -f boot/*.so
	rm -f cdrom/fat.img cdrom/kernel cdrom/mod/* cdrom/ramdisk.img
	rm -f fatbase/kernel fatbase/efi/boot/bootia32.efi fatbase/efi/boot/bootx64.efi
	rm -f cdrom/netinit fatbase/netinit
	rm -f ${KERNEL_OBJS} ${KERNEL_ASMOBJS} kernel/symbols.o kernel/symbols.S
	rm -f base/lib/crt*.o
	rm -f ${MODULES}
	rm -f ${APPS_Y} ${LIBS_Y}

QEMU_ARGS=-serial mon:stdio -m 1G -soundhw ac97,pcspk -enable-kvm -rtc base=localtime

.PHONY: run
run: image.iso
	qemu-system-i386 -cdrom $< ${QEMU_ARGS}

.PHONY: fast
fast: image.iso
	qemu-system-i386 -cdrom $< ${QEMU_ARGS} \
	  -fw_cfg name=opt/org.toaruos.bootmode,string=normal

.PHONY: headless
headless: image.iso
	@qemu-system-i386 -cdrom $< ${QEMU_ARGS} \
	  -nographic \
	  -fw_cfg name=opt/org.toaruos.bootmode,string=headless

.PHONY: efi64
efi64: image.iso
	qemu-system-x86_64 -cdrom $< ${QEMU_ARGS} \
	  -bios /usr/share/qemu/OVMF.fd

VMNAME=ToaruOS-NIH CD

define virtualbox-runner =
.PHONY: $1
$1: image.iso
	-VBoxManage unregistervm "$(VMNAME)" --delete
	VBoxManage createvm --name "$(VMNAME)" --ostype $2 --register
	VBoxManage modifyvm "$(VMNAME)" --memory 1024 --vram 32 --audio pulse --audiocontroller ac97 --bioslogodisplaytime 1 --bioslogofadeout off --bioslogofadein off --biosbootmenu disabled $3
	VBoxManage storagectl "$(VMNAME)" --add ide --name "IDE"
	VBoxManage storageattach "$(VMNAME)" --storagectl "IDE" --port 0 --device 0 --medium $$(shell pwd)/image.iso --type dvddrive
	VBoxManage setextradata "$(VMNAME)" GUI/DefaultCloseAction PowerOff
	VBoxManage startvm "$(VMNAME)" --type separate
endef

$(eval $(call virtualbox-runner,virtualbox,"Other",))
$(eval $(call virtualbox-runner,virtualbox-efi,"Other",--firmware efi))
$(eval $(call virtualbox-runner,virtualbox-efi64,"Other_64",--firmware efi))