#
# Makefile Configuration
#

CC=cc
LD=ld
AS=nasm
ARCH=amd64
ARCH_COMMON=x86_common

BUILD=build

CFLAGS += -std=c2x -ffreestanding -lgcc -isystem include -pipe
CFLAGS += -Wall -Wextra -pedantic
CFLAGS += -O2 -g -fno-stack-protector -fno-omit-frame-pointer
CFLAGS += -DPAGE_SIZE=4096

LDFLAGS += -nmagic --no-warn-rwx-segments -nostdlib

#
# Makefile
#

ARCH_COMMON += $(ARCH)

KERNEL=kernel.bin
ISO=os_image.iso

ARCH_DIRS = $(patsubst %,src/arch/%,$(ARCH_COMMON))
ARCH_INCLUDES = $(shell find $(ARCH_DIRS) -type d -name "include")
CFLAGS_ARCH = $(patsubst %, -isystem %,$(ARCH_INCLUDES))

H_SRC = $(shell find src include -type f -name "*.h" -not -path "src/arch/*")
HA_SRC  = $(shell find $(ARCH_DIRS) -type f -name "*.h")

C_SRC  = $(shell find src -type f -name "*.c" -not -path "src/arch/*")
C_OBJ = $(patsubst %.c,build/%.o,$(C_SRC))
CA_SRC = $(shell find $(ARCH_DIRS) -type f -name "*.c")
CA_OBJ = $(patsubst %.c,build/%.o,$(CA_SRC))

A_SRC  = $(shell find $(ARCH_DIRS) -type f -name "*.S")
A_OBJ  = $(patsubst %.S,build/%.S.o,$(A_SRC))

.PHONY: all clean

all: build/$(ISO)

clean:
	@printf "\033[31m  RM  \033[0m%s\n" build
	@rm -fr ./build

$(A_OBJ): build/%.S.o : %.S
	@mkdir -p $(@D)
	@printf "\033[33m  AS  \033[0m%s\n" $<
	@nasm $< -f elf64 -o $@

$(C_OBJ): build/%.o : %.c
	@mkdir -p $(@D)
	@printf "\033[34m  CC  \033[0m%s\n" $<
	@$(CC) -c $(CFLAGS) -o $@ $<

$(CA_OBJ): build/%.o : %.c
	@mkdir -p $(@D)
	@printf "\033[34m  CC  \033[0m%s\n" $<
	@$(CC) -c $(CFLAGS) $(CFLAGS_ARCH) -o $@ $<

build/$(KERNEL): arch/$(ARCH)/linker.ld $(A_OBJ) $(C_OBJ) $(CA_OBJ) $(H_SRC) $(HA_SRC)
	@mkdir -p $(@D)
	@printf "\033[32m  LD  \033[0m%s\n" $@
	@$(LD) $(LDFLAGS) -T arch/$(ARCH)/linker.ld -o build/$(KERNEL) $(A_OBJ) $(C_OBJ) $(CA_OBJ)

build/$(ISO): build/$(KERNEL) grub.cfg
	@mkdir -p $(@D)
	@mkdir -p build/iso/boot/grub
	@cp grub.cfg build/iso/boot/grub
	@cp build/$(KERNEL) build/iso/boot
	@printf "\033[35m ISO  \033[0m%s\n" build/$(ISO)
	@grub-mkrescue -o build/$(ISO) build/iso 2> /dev/null

run: all
	@qemu-system-x86_64 \
		-cdrom build/$(ISO) \
		-serial stdio \
		-display sdl \
		-m 1G \
		-enable-kvm \
		-name corn