# Default target is x86_64-unknown-none
TARGET ?= "x86_64-unknown-none"
# Limine BIOS file directory
LIMINEDIR ?= "/usr/share/limine"

# QEMU system is set accordingly and automatically
qemu = "qemu-system-x86_64"
# List of required BIOS files
limine-files = limine-bios.sys limine-bios-cd.bin limine-bios-uefi-cd.bin BOOTX64.EFI BOOTIA32.EFI BOOTAA64.EFI BOOTLOONGARCH64.EFI BOOTRISCV64.EFI

# Properly set QEMU command
ifeq ($(TARGET),x86_64-unknown-none)
	qemu = "qemu-system-x86_64"
else ifeq ($(TARGET),riscv64gc-unknown-none-elf)
	qemu = "qemu-system-riscv64"
else ifeq ($(TARGET),aarch64-unknown-none)
	qemu = "qemu-system-aarch64"
	qemu += "-machine"
	qemu += "orangepi-pc"
else ifeq ($(TARGET),loongarch64-unknown-none)
	qemu = "qemu-system-loongarch64"
endif

executables = rustup xorriso limine tree $(qemu)

all: kernel iso run

checkenv:
	
	$(info "Limine directory: $(LIMINEDIR)")	
	$(foreach file,$(limine-files),\
		$(if $(shell test -f $(LIMINEDIR)/$(file) | echo "it exists"),$(info "Found $(file)"),$(error "No $(file) in $(LIMINEDIR)")))

	$(foreach exec,$(executables),\
    	$(if $(shell which $(exec)),$(info "Found $(exec)"),$(error "No $(exec) in PATH")))

# Prepare toolchain
prepare: checkenv

	rustup install nightly
	rustup target add $(TARGET)

# Run the ISO in an emulator.
run: iso

	$(qemu) -drive file=build/gila.iso,format=raw,index=0,media=disk

# Build the bootable kernel image.
.PHONY: build/kernel
kernel: prepare $(shell find src/kernel/ -type f -name *.rs) $(shell find src/kernel/ -type f -name linker.ld)

	cargo build --bin kernel --release -Zunstable-options --artifact-dir=build

# Build a bootable ISO and install Limine.
.PHONY: build/gila.iso
iso: kernel limine.conf

	mkdir -p build/iso/boot/limine
	mkdir -p build/iso/EFI/BOOT

	# Copy Limine files
	cp ./limine.conf build/iso/
	cp $(LIMINEDIR)/limine-bios.sys build/iso/boot/limine/
	cp $(LIMINEDIR)/limine-bios-cd.bin build/iso/boot/limine/
	cp $(LIMINEDIR)/limine-uefi-cd.bin build/iso/boot/limine/
	cp $(LIMINEDIR)/BOOTX64.EFI build/iso/EFI/BOOT/
	cp $(LIMINEDIR)/BOOTIA32.EFI build/iso/EFI/BOOT/
	cp $(LIMINEDIR)/BOOTAA64.EFI build/iso/EFI/BOOT/
	cp $(LIMINEDIR)/BOOTLOONGARCH64.EFI build/iso/EFI/BOOT
	cp $(LIMINEDIR)/BOOTRISCV64.EFI build/iso/EFI/BOOT

	# Copy kernel
	mv build/kernel build/iso/boot/

	# Build filesystem tree
	mkdir -p build/iso/system/bin
	mkdir -p build/iso/system/tmp
	mkdir -p build/iso/system/cfg

	xorriso -as mkisofs -b boot/limine/limine-bios-cd.bin -no-emul-boot \
	-boot-load-size 4 -boot-info-table --efi-boot \
    boot/limine/limine-uefi-cd.bin -efi-boot-part --efi-boot-image \
    --protective-msdos-label build/iso -o build/gila.iso
	limine bios-install build/gila.iso

	tree build/iso/

clean:
	rm -rf build
	cargo clean