# I hate GNU Make
#
# Seriously.
#
# Fuck M4. I do this because it's probably the most portable way, and I don't
# wan't to write Yet Another Compile System because fuck that shit. I could
# use cmake but I don't know whether it is flexible enough. It probably is
# but whatever. I wrote this piece of shit below, let's just keep it that
# way. There are better way to do the hthings I do below, but who gives a
# shit.

default: emulate-nohdd

SHELL:=/bin/bash
ENV:=/usr/xdev/bin
TARGET:=i586-elf
CC:=$(ENV)/$(TARGET)-gcc
CX:=$(ENV)/$(TARGET)-g++
AS:=nasm
LD:=$(ENV)/$(TARGET)-ld

CFLAGS:=-Wall -Wextra -Werror -nostdlib -nostartfiles -nodefaultlibs -std=c99
CFLAGS+=-I ./include
LFLAGS:=-nostdlib -nostartfiles -nodefaultlibs

.PHONY: all clean kernel.bin emulate hdd.img

obj/src/%.nao : src/%.asm
	@echo "[i] Assembling $*.asm..."
	@$(AS) -f elf -o obj/src/$*.nao src/$*.asm

obj/src/%.o : src/%.c
	@echo "[i] Compiling $*.c ..."
	@mkdir -p obj/src/$*.o
	@rmdir obj/src/$*.o
	@$(CC) $(CFLAGS) -c src/$*.c -o obj/src/$*.o

TIER0SRC := $(shell find src/Tier0 -mindepth 1 -maxdepth 3 -name "*.c")
TIER0SRC += $(shell find src/Tier0 -mindepth 1 -maxdepth 3 -name "*.asm")

TIER0OBJ := $(patsubst %.c,%.o,$(TIER0SRC))
TIER0OBJ := $(patsubst %.asm,%.nao,$(TIER0OBJ))

TIER0 := $(foreach i, $(TIER0OBJ), obj/$(i))

Tier0: $(TIER0)

kernel.bin: Tier0
	@echo "[i] Linking kernel.bin..."
	@$(LD) -T src/kernel.ld -o kernel.bin $(TIER0)

hdd.img: kernel.bin
	@echo "[i] Creating HDD image..."
	@if [ -e hdd_temp.img ] ; then rm hdd_temp.img ; fi
	@dd if=/dev/zero of=hdd_temp.img bs=512 count=10240 2> /dev/null
	@mkfs.vfat hdd_temp.img
	@syslinux hdd_temp.img
	@mcopy -i hdd_temp.img /usr/lib/syslinux/mboot.c32 ::mboot.c32
	@mcopy -i hdd_temp.img kernel.bin ::kernel.bin
	@mcopy -i hdd_temp.img dst/syslinux.cfg ::syslinux.cfg
	@mv hdd_temp.img hdd.img

emulate-nohdd: kernel.bin
	@echo "[i] Starting QEmu..."
	@qemu -kernel kernel.bin

emulate: hdd.img
	@echo "[i] Starting QEmu..."
	@qemu -hda hdd.img

clean:
	@rm -Rf obj
	@if [ -e kernel.bin ] ; then rm kernel.bin ; fi
	@if [ -e hdd_temp.img ] ; then rm hdd_temp.img ; fi
	@if [ -e hdd.img ] ; then rm hdd.img; fi