# Nuke built-in rules and variables.
MAKEFLAGS += -rR
.SUFFIXES:

# Target architecture to build for. Default to x86_64.
ARCH := x86_64

# Default user QEMU flags. These are appended to the QEMU command calls.
QEMUFLAGS := -smp 4 -m 2G -d int -D qemu.log -no-reboot

override IMAGE_NAME := montauk-$(ARCH)

# KERNEL_ONLY=1 builds a ramdisk holding just the boot files (no
# userspace), for bringing up a kernel on a new architecture.
KERNEL_ONLY ?= 0

# programs/ builds x86_64 into bin/, other architectures into bin-<arch>/.
ifeq ($(ARCH),x86_64)
    PROGRAMS_BIN := programs/bin
else
    PROGRAMS_BIN := programs/bin-$(ARCH)
endif

override EFI_LOADER_x86_64 := BOOTX64.EFI
override EFI_LOADER_aarch64 := BOOTAA64.EFI
override EFI_LOADER_riscv64 := BOOTRISCV64.EFI
override EFI_LOADER_loongarch64 := BOOTLOONGARCH64.EFI

# The host strip handles x86_64 images; other targets use their toolchain's.
ifeq ($(ARCH),x86_64)
    STRIP := strip
else
    STRIP := toolchain/local/bin/$(ARCH)-montauk-strip
endif

# AArch64 UEFI firmware for QEMU (Debian/Ubuntu: qemu-efi-aarch64).
AARCH64_EFI_FIRMWARE ?= /usr/share/qemu-efi-aarch64/QEMU_EFI.fd

# Toolchain for building the 'limine' executable for the host.
HOST_CC := cc
HOST_CFLAGS := -g -O2 -pipe
HOST_CPPFLAGS :=
HOST_LDFLAGS :=
HOST_LIBS :=

.PHONY: all
all: $(IMAGE_NAME).iso

.PHONY: all-hdd
all-hdd: $(IMAGE_NAME).hdd

.PHONY: run
run: run-$(ARCH)

.PHONY: run-hdd
run-hdd: run-hdd-$(ARCH)

.PHONY: run-x86_64
run-x86_64: $(IMAGE_NAME).iso
	qemu-system-$(ARCH) \
		-enable-kvm \
		-M q35 \
		-bios /usr/share/ovmf/OVMF.fd \
		-cdrom $(IMAGE_NAME).iso \
		-device e1000,netdev=net0,mac=52:54:00:68:00:99 \
		-netdev user,id=net0 \
		$(QEMUFLAGS)

.PHONY: run-hdd-x86_64
run-hdd-x86_64: $(IMAGE_NAME).hdd
	qemu-system-$(ARCH) \
		-M q35 \
		-bios /usr/share/ovmf/OVMF.fd \
		-hda $(IMAGE_NAME).hdd \
		-device e1000,netdev=net0,mac=52:54:00:68:00:99 \
		-netdev user,id=net0 \
		$(QEMUFLAGS)

.PHONY: run-aarch64
# The machine mirrors the Raspberry Pi 4/400: Cortex-A72 cores, a GICv2, and
# keyboard and mouse behind a hub (every USB 2 device on the Pi is: the
# VL805's one USB 2 port carries an on-board hub). QEMU's hub is full-speed,
# so the transaction-translator path is only exercised on the real board.
# The kernel console is mirrored to the PL011 (-serial stdio).
run-aarch64: $(IMAGE_NAME).iso
	qemu-system-$(ARCH) \
		-M virt,gic-version=2 \
		-cpu cortex-a72 \
		-device ramfb \
		-device qemu-xhci,id=xhci \
		-device usb-hub,bus=xhci.0,port=1 \
		-device usb-kbd,bus=xhci.0,port=1.1 \
		-device usb-mouse,bus=xhci.0,port=1.2 \
		-bios $(AARCH64_EFI_FIRMWARE) \
		-cdrom $(IMAGE_NAME).iso \
		-serial stdio \
		$(QEMUFLAGS)

.PHONY: run-hdd-aarch64
run-hdd-aarch64: $(IMAGE_NAME).hdd
	qemu-system-$(ARCH) \
		-M virt,gic-version=2 \
		-cpu cortex-a72 \
		-device ramfb \
		-device qemu-xhci,id=xhci \
		-device usb-hub,bus=xhci.0,port=1 \
		-device usb-kbd,bus=xhci.0,port=1.1 \
		-device usb-mouse,bus=xhci.0,port=1.2 \
		-bios $(AARCH64_EFI_FIRMWARE) \
		-drive if=none,id=hd0,format=raw,file=$(IMAGE_NAME).hdd \
		-device virtio-blk-pci,drive=hd0 \
		-serial stdio \
		$(QEMUFLAGS)

# The SD card image on QEMU, with the root read through the SDHCI driver:
# the card goes on sdhci-pci as a padded copy (QEMU wants a power-of-two card;
# RPI4_QEMU_CARD_MIB, default 4 GiB, leaves the first-boot grow room to work
# with; every run starts from a fresh copy, so every run is a first boot),
# and since QEMU's UEFI has no SD driver, the card's ESP is also
# attached alone (the card's first partition, as its own disk) over virtio
# for the firmware to boot Limine from.
RPI4_QEMU_CARD_MIB ?= 4096
.PHONY: run-rpi4-sd
run-rpi4-sd: montauk-rpi4.img
	cp --sparse=always montauk-rpi4.img rpi4-sd-qemu.img
	size=$$(stat -c %s rpi4-sd-qemu.img); p=$$(($(RPI4_QEMU_CARD_MIB) * 1048576)); \
		while [ $$p -lt $$size ]; do p=$$((p * 2)); done; truncate -s $$p rpi4-sd-qemu.img
	end=$$(PATH=$$PATH:/usr/sbin:/sbin sfdisk -d montauk-rpi4.img | awk -F'[=,]' '/montauk-rpi4.img1/ {print $$2 + $$4}'); \
		dd if=montauk-rpi4.img of=rpi4-esp-qemu.img bs=512 count=$$end status=none
	PATH=$$PATH:/usr/sbin:/sbin sfdisk --quiet --delete rpi4-esp-qemu.img 2 2>/dev/null || true
	qemu-system-aarch64 \
		-M virt,gic-version=2 \
		-cpu cortex-a72 \
		-device ramfb \
		-device qemu-xhci,id=xhci \
		-device usb-hub,bus=xhci.0,port=1 \
		-device usb-kbd,bus=xhci.0,port=1.1 \
		-device usb-mouse,bus=xhci.0,port=1.2 \
		-bios $(AARCH64_EFI_FIRMWARE) \
		-drive if=none,id=esp,format=raw,file=rpi4-esp-qemu.img \
		-device virtio-blk-pci,drive=esp \
		-device sdhci-pci \
		-drive if=none,id=sd,format=raw,file=rpi4-sd-qemu.img \
		-device sd-card,drive=sd \
		-serial stdio \
		$(QEMUFLAGS)

.PHONY: run-riscv64
run-riscv64: $(IMAGE_NAME).iso
	qemu-system-$(ARCH) \
		-M virt \
		-cpu rv64 \
		-device ramfb \
		-device qemu-xhci,id=xhci \
		-device usb-kbd,bus=xhci.0 \
		-device usb-mouse,bus=xhci.0 \
		-bios /usr/share/ovmf/OVMF.fd \
		-cdrom $(IMAGE_NAME).iso \
		$(QEMUFLAGS)

.PHONY: run-hdd-riscv64
run-hdd-riscv64: $(IMAGE_NAME).hdd
	qemu-system-$(ARCH) \
		-M virt \
		-cpu rv64 \
		-device ramfb \
		-device qemu-xhci,id=xhci \
		-device usb-kbd,bus=xhci.0 \
		-device usb-mouse,bus=xhci.0 \
		-bios /usr/share/ovmf/OVMF.fd \
		-hda $(IMAGE_NAME).hdd \
		$(QEMUFLAGS)

.PHONY: run-loongarch64
run-loongarch64: $(IMAGE_NAME).iso
	qemu-system-$(ARCH) \
		-M virt \
		-cpu la464 \
		-device ramfb \
		-device qemu-xhci,id=xhci \
		-device usb-kbd,bus=xhci.0 \
		-device usb-mouse,bus=xhci.0 \
		-bios /usr/share/ovmf/OVMF.fd \
		-cdrom $(IMAGE_NAME).iso \
		$(QEMUFLAGS)

.PHONY: run-hdd-loongarch64
run-hdd-loongarch64: $(IMAGE_NAME).hdd
	qemu-system-$(ARCH) \
		-M virt \
		-cpu la464 \
		-device ramfb \
		-device qemu-xhci,id=xhci \
		-device usb-kbd,bus=xhci.0 \
		-device usb-mouse,bus=xhci.0 \
		-bios /usr/share/ovmf/OVMF.fd \
		-hda $(IMAGE_NAME).hdd \
		$(QEMUFLAGS)


.PHONY: run-bios
run-bios: $(IMAGE_NAME).iso
	qemu-system-$(ARCH) \
		-M q35 \
		-cdrom $(IMAGE_NAME).iso \
		-boot d \
		-device e1000,netdev=net0,mac=52:54:00:68:00:99 \
		-netdev user,id=net0 \
		$(QEMUFLAGS)

.PHONY: run-hdd-bios
run-hdd-bios: $(IMAGE_NAME).hdd
	qemu-system-$(ARCH) \
		-M q35 \
		-hda $(IMAGE_NAME).hdd \
		-device e1000,netdev=net0,mac=52:54:00:68:00:99 \
		-netdev user,id=net0 \
		$(QEMUFLAGS)

.PHONY: toolchain
toolchain:
	./toolchain/build-toolchain.sh

# Build the Montauk SDK: native binutils + GCC that run on MontaukOS,
# shipped into the image at 0:/sdk by the programs/ devkit target.
# One-time (long) build; idempotent afterwards.
.PHONY: sdk
sdk:
	./toolchain/build-native-sdk.sh

limine/limine:
	rm -rf limine
	git clone https://github.com/limine-bootloader/limine.git --branch=v9.x-binary --depth=1
	$(MAKE) -C limine \
		CC="$(HOST_CC)" \
		CFLAGS="$(HOST_CFLAGS)" \
		CPPFLAGS="$(HOST_CPPFLAGS)" \
		LDFLAGS="$(HOST_LDFLAGS)" \
		LIBS="$(HOST_LIBS)"

kernel-deps:
	./kernel/get-deps
	touch kernel-deps

.PHONY: kernel
kernel: kernel-deps
	$(MAKE) -C kernel

.PHONY: programs
programs:
	$(MAKE) -C programs

# Build out-of-tree ports (~/dev/mtkports) and stage their app bundles into
# programs/bin/apps/. Opt-in: the base ISO ships only what lives in
# programs/src/, so this is never a dependency of the default build. Run it
# before 'make ramdisk' to include ports in the image.
MTKPORTS ?= $(HOME)/dev/mtkports

.PHONY: ports
ports: programs
	@if [ -d "$(MTKPORTS)" ]; then \
	    $(MAKE) -C "$(MTKPORTS)" install MONTAUKOS="$(CURDIR)"; \
	else \
	    echo "ports: $(MTKPORTS) not found - skipping (set MTKPORTS=/path/to/mtkports)"; \
	fi

.PHONY: ramdisk
ifeq ($(KERNEL_ONLY),1)
ramdisk: limine/limine kernel
	rm -rf .kernel-only-root
	mkdir -p .kernel-only-root/boot/limine
	cp -v limine/$(EFI_LOADER_$(ARCH)) limine.conf .kernel-only-root/boot/limine/
	cp -v kernel/bin-$(ARCH)/kernel .kernel-only-root/boot/
	./scripts/mkramdisk.sh .kernel-only-root ramdisk.tar
	rm -rf .kernel-only-root
else
ramdisk: limine/limine kernel programs
	mkdir -p $(PROGRAMS_BIN)/boot/limine
	cp -v limine/$(EFI_LOADER_$(ARCH)) $(PROGRAMS_BIN)/boot/limine/
	cp -v limine.conf $(PROGRAMS_BIN)/boot/limine/
	cp -v kernel/bin-$(ARCH)/kernel $(PROGRAMS_BIN)/boot/
	rm -f $(PROGRAMS_BIN)/boot/ramdisk.tar
	./scripts/mkramdisk.sh $(PROGRAMS_BIN) ramdisk.tar
endif

$(IMAGE_NAME).iso: limine/limine kernel ramdisk
	rm -rf iso_root
	mkdir -p iso_root/boot
	cp -v kernel/bin-$(ARCH)/kernel iso_root/boot/
	cp -v ramdisk.tar iso_root/boot/
	mkdir -p iso_root/boot/limine
	cp -v limine.conf iso_root/boot/limine/
	mkdir -p iso_root/EFI/BOOT
ifeq ($(ARCH),x86_64)
	cp -v limine/limine-bios.sys limine/limine-bios-cd.bin limine/limine-uefi-cd.bin iso_root/boot/limine/
	cp -v limine/BOOTX64.EFI iso_root/EFI/BOOT/
	cp -v limine/BOOTIA32.EFI iso_root/EFI/BOOT/
	xorriso -as mkisofs -R -r -J -b boot/limine/limine-bios-cd.bin \
		-no-emul-boot -boot-load-size 4 -boot-info-table -hfsplus \
		-apm-block-size 2048 --efi-boot boot/limine/limine-uefi-cd.bin \
		-efi-boot-part --efi-boot-image --protective-msdos-label \
		iso_root -o $(IMAGE_NAME).iso
	./limine/limine bios-install $(IMAGE_NAME).iso
endif
ifeq ($(ARCH),aarch64)
	cp -v limine/limine-uefi-cd.bin iso_root/boot/limine/
	cp -v limine/BOOTAA64.EFI iso_root/EFI/BOOT/
	xorriso -as mkisofs -R -r -J \
		-hfsplus -apm-block-size 2048 \
		--efi-boot boot/limine/limine-uefi-cd.bin \
		-efi-boot-part --efi-boot-image --protective-msdos-label \
		iso_root -o $(IMAGE_NAME).iso
endif
ifeq ($(ARCH),riscv64)
	cp -v limine/limine-uefi-cd.bin iso_root/boot/limine/
	cp -v limine/BOOTRISCV64.EFI iso_root/EFI/BOOT/
	xorriso -as mkisofs -R -r -J \
		-hfsplus -apm-block-size 2048 \
		--efi-boot boot/limine/limine-uefi-cd.bin \
		-efi-boot-part --efi-boot-image --protective-msdos-label \
		iso_root -o $(IMAGE_NAME).iso
endif
ifeq ($(ARCH),loongarch64)
	cp -v limine/limine-uefi-cd.bin iso_root/boot/limine/
	cp -v limine/BOOTLOONGARCH64.EFI iso_root/EFI/BOOT/
	xorriso -as mkisofs -R -r -J \
		-hfsplus -apm-block-size 2048 \
		--efi-boot boot/limine/limine-uefi-cd.bin \
		-efi-boot-part --efi-boot-image --protective-msdos-label \
		iso_root -o $(IMAGE_NAME).iso
endif
	rm -rf iso_root

# Example and regression-test programs that are built into 0:/os for
# development but have no place on a release image.
RELEASE_EXCLUDE_PROGRAMS := rusthello.elf futextest.elf memtest.elf

.PHONY: release
release: limine/limine kernel ramdisk
	rm -rf iso_root .release-tmp
	mkdir -p iso_root/boot
	cp kernel/bin-$(ARCH)/kernel iso_root/boot/
	$(STRIP) iso_root/boot/kernel
	cp -r $(PROGRAMS_BIN) .release-tmp
# A release ISO ships only in-tree apps, so drop any out-of-tree port bundles
# that happen to be staged in programs/bin/apps (each carries a .port marker).
# Pass RELEASE_WITH_PORTS=1 to deliberately cut a ports-included image.
ifneq ($(RELEASE_WITH_PORTS),1)
	@for m in $$(find .release-tmp/apps -name .port 2>/dev/null); do \
	    d=$$(dirname $$m); \
	    echo "release: excluding port bundle $$(basename $$d)"; \
	    rm -rf "$$d"; \
	done
else
	@echo "release: RELEASE_WITH_PORTS=1 - including out-of-tree port bundles"
endif
# The Montauk SDK (native GCC + binutils and their target sysroot under
# 0:/sdk) dominates the image size. Pass RELEASE_WITHOUT_SDK=1 to cut a slim
# ISO without it. Only the devkit-owned subtrees go: sdk/tcc and sdk/lua are
# installed by their own targets and stay, as does 0:/tmp, which the libc
# uses for tmpnam() and not just for compiler intermediates.
ifeq ($(RELEASE_WITHOUT_SDK),1)
	@echo "release: RELEASE_WITHOUT_SDK=1 - excluding the Montauk SDK (0:/sdk dev tools)"
	rm -rf .release-tmp/sdk/bin .release-tmp/sdk/lib .release-tmp/sdk/include \
	       .release-tmp/sdk/libexec .release-tmp/sdk/x86_64-montauk
endif
	rm -f $(addprefix .release-tmp/os/,$(RELEASE_EXCLUDE_PROGRAMS))
	find .release-tmp -name '*.elf' -exec $(STRIP) {} +
# The ramdisk carries its own copy of the kernel at 0:/boot/kernel -- that is
# the image the Installer lays down on the target disk -- and it is not named
# *.elf, so the find above misses it. Unstripped it is ~6 MB against ~0.7 MB.
	$(STRIP) .release-tmp/boot/kernel
	./scripts/mkramdisk.sh .release-tmp iso_root/boot/ramdisk.tar
	rm -rf .release-tmp
	mkdir -p iso_root/boot/limine
	cp limine.conf iso_root/boot/limine/
	mkdir -p iso_root/EFI/BOOT
ifeq ($(ARCH),x86_64)
	cp limine/limine-bios.sys limine/limine-bios-cd.bin limine/limine-uefi-cd.bin iso_root/boot/limine/
	cp limine/BOOTX64.EFI iso_root/EFI/BOOT/
	cp limine/BOOTIA32.EFI iso_root/EFI/BOOT/
	xorriso -as mkisofs -R -r -J -b boot/limine/limine-bios-cd.bin \
		-no-emul-boot -boot-load-size 4 -boot-info-table -hfsplus \
		-apm-block-size 2048 --efi-boot boot/limine/limine-uefi-cd.bin \
		-efi-boot-part --efi-boot-image --protective-msdos-label \
		iso_root -o $(IMAGE_NAME).iso
	./limine/limine bios-install $(IMAGE_NAME).iso
endif
ifeq ($(ARCH),aarch64)
	cp limine/limine-uefi-cd.bin iso_root/boot/limine/
	cp limine/BOOTAA64.EFI iso_root/EFI/BOOT/
	xorriso -as mkisofs -R -r -J \
		-hfsplus -apm-block-size 2048 \
		--efi-boot boot/limine/limine-uefi-cd.bin \
		-efi-boot-part --efi-boot-image --protective-msdos-label \
		iso_root -o $(IMAGE_NAME).iso
endif
ifeq ($(ARCH),riscv64)
	cp limine/limine-uefi-cd.bin iso_root/boot/limine/
	cp limine/BOOTRISCV64.EFI iso_root/EFI/BOOT/
	xorriso -as mkisofs -R -r -J \
		-hfsplus -apm-block-size 2048 \
		--efi-boot boot/limine/limine-uefi-cd.bin \
		-efi-boot-part --efi-boot-image --protective-msdos-label \
		iso_root -o $(IMAGE_NAME).iso
endif
ifeq ($(ARCH),loongarch64)
	cp limine/limine-uefi-cd.bin iso_root/boot/limine/
	cp limine/BOOTLOONGARCH64.EFI iso_root/EFI/BOOT/
	xorriso -as mkisofs -R -r -J \
		-hfsplus -apm-block-size 2048 \
		--efi-boot boot/limine/limine-uefi-cd.bin \
		-efi-boot-part --efi-boot-image --protective-msdos-label \
		iso_root -o $(IMAGE_NAME).iso
endif
	rm -rf iso_root

# Raspberry Pi 4/400 SD card image (UEFI firmware + Limine + MontaukOS).
# ROOTFS=ext2 (default) puts the system on an ext2 partition read through the
# kernel's SD driver; ROOTFS=ramdisk has Limine load ramdisk.tar instead.
# Phony so switching ROOTFS always rebuilds the image.
ROOTFS ?= ext2
.PHONY: rpi4-sd montauk-rpi4.img
rpi4-sd: montauk-rpi4.img

montauk-rpi4.img: limine/limine kernel ramdisk
ifneq ($(ARCH),aarch64)
	$(error rpi4-sd needs ARCH=aarch64)
endif
	./scripts/mk-rpi4-sd.sh kernel/bin-$(ARCH)/kernel ramdisk.tar $@ $(ROOTFS) $(PROGRAMS_BIN)-rpi

# Graphical imager: write montauk-rpi4.img to an SD card, or update the
# installation on one in place (scripts/montauk-imager.py, docs/raspberry-pi.md).
.PHONY: rpi4-imager
rpi4-imager:
	./scripts/montauk-imager.py

$(IMAGE_NAME).hdd: limine/limine kernel ramdisk
	rm -f $(IMAGE_NAME).hdd
	dd if=/dev/zero bs=1M count=0 seek=64 of=$(IMAGE_NAME).hdd
	PATH=$$PATH:/usr/sbin:/sbin sgdisk $(IMAGE_NAME).hdd -n 1:2048 -t 1:ef00
ifeq ($(ARCH),x86_64)
	./limine/limine bios-install $(IMAGE_NAME).hdd
endif
	mformat -i $(IMAGE_NAME).hdd@@1M
	mmd -i $(IMAGE_NAME).hdd@@1M ::/EFI ::/EFI/BOOT ::/boot ::/boot/limine
	mcopy -i $(IMAGE_NAME).hdd@@1M kernel/bin-$(ARCH)/kernel ::/boot
	mcopy -i $(IMAGE_NAME).hdd@@1M ramdisk.tar ::/boot
	mcopy -i $(IMAGE_NAME).hdd@@1M limine.conf ::/boot/limine
ifeq ($(ARCH),x86_64)
	mcopy -i $(IMAGE_NAME).hdd@@1M limine/limine-bios.sys ::/boot/limine
	mcopy -i $(IMAGE_NAME).hdd@@1M limine/BOOTX64.EFI ::/EFI/BOOT
	mcopy -i $(IMAGE_NAME).hdd@@1M limine/BOOTIA32.EFI ::/EFI/BOOT
endif
ifeq ($(ARCH),aarch64)
	mcopy -i $(IMAGE_NAME).hdd@@1M limine/BOOTAA64.EFI ::/EFI/BOOT
endif
ifeq ($(ARCH),riscv64)
	mcopy -i $(IMAGE_NAME).hdd@@1M limine/BOOTRISCV64.EFI ::/EFI/BOOT
endif
ifeq ($(ARCH),loongarch64)
	mcopy -i $(IMAGE_NAME).hdd@@1M limine/BOOTLOONGARCH64.EFI ::/EFI/BOOT
endif

.PHONY: clean
clean:
	$(MAKE) -C kernel clean
# 	$(MAKE) -C programs clean
	rm -rf iso_root .release-tmp $(IMAGE_NAME).iso $(IMAGE_NAME).hdd montauk-rpi4.img rpi4-sd-qemu.img rpi4-esp-qemu.img ramdisk.tar

.PHONY: distclean
distclean:
	$(MAKE) -C kernel distclean
	rm -rf iso_root *.iso *.hdd kernel-deps limine ovmf