# Copyright (C) 2025 Elaina Claus
# 
#     This program is free software: you can redistribute it and/or modify
#     it under the terms of the GNU General Public License as published by
#     the Free Software Foundation, either version 3 of the License, or
#     (at your option) any later version.
# 
#     This program is distributed in the hope that it will be useful,
#     but WITHOUT ANY WARRANTY; without even the implied warranty of
#     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
#     GNU General Public License for more details.
# 
#     You should have received a copy of the GNU General Public License
#     along with this program.  If not, see <https://www.gnu.org/licenses/>.

INCDIR := include
BUILD_DIR := build
IMG := $(BUILD_DIR)/disk.img
IMGZ := $(BUILD_DIR)/disk.img.gz

# Get current Git version (tag) and hash
GIT_VERSION := $(shell git describe --tags)
GIT_HASH := $(shell git rev-parse HEAD)
GIT_NASM_DEFINES := -D __GIT_VER__='"$(GIT_VERSION)"' -D __GIT_HASH__='"$(GIT_HASH)"'

NASMFLAGS   := -Wall -f bin -i$(INCDIR)/ $(GIT_NASM_DEFINES)

QEMU        ?= qemu-system-i386
QEMU_OPTS   ?= -L ./bin/ -bios bios.bin -cpu pentium3 -m 128 -S -s -monitor stdio -nic none
.PHONY: all mbr vbr stage2 boottest clean run run_qemu run_bochs img imgz help

mbr_source_files := $(wildcard src/mbr/*.nasm)
vbr_source_files := $(wildcard src/vbr/*.nasm)
stage2_source_files := $(wildcard src/stage2/*.nasm)
boottest_source_files := $(wildcard src/miniboot32/*.nasm)

mbr_binary_files := $(patsubst src/mbr/%.nasm, build/%.bin, $(mbr_source_files))
vbr_binary_files := $(patsubst src/vbr/%.nasm, build/%.bin, $(vbr_source_files))
stage2_binary_files := $(patsubst src/stage2/%.nasm, build/%.bin, $(stage2_source_files))
boottest_binary_files := $(patsubst src/miniboot32/%.nasm, build/%.bin, $(boottest_source_files))

all: $(IMG) $(IMGZ) $(mbr_binary_files) $(vbr_binary_files) $(stage2_binary_files)
mbr: $(mbr_binary_files)
vbr: $(vbr_binary_files)
stage2: $(stage2_binary_files)
boottest: $(boottest_binary_files)

clean:
	@rm -v $(BUILD_DIR)/*.bin
	@rm -v $(BUILD_DIR)/*.map
	@rm -v $(BUILD_DIR)/*.img
	@rm -v $(BUILD_DIR)/output/*.img.gz
	@rm -v $(BUILD_DIR)/output/*.tar.gz

run: $(IMG)
	@$(QEMU) $(QEMU_OPTS) -hda $(IMG)

run_bochs: $(IMG)
	@bochs -q

img: $(IMG)
	@file $(IMG)

imgz: $(IMGZ)
	@file $(IMGZ)

build/%.bin: src/mbr/%.nasm
	@mkdir -p $(shell dirname $@)
	@nasm $(NASMFLAGS) $(GIT_NASM_DEFINES) $< -o $@

build/%.bin: src/vbr/%.nasm
	@mkdir -p $(shell dirname $@)
	@nasm $(NASMFLAGS) $(GIT_NASM_DEFINES) $< -o $@

build/%.bin: src/stage2/%.nasm
	@mkdir -p $(shell dirname $@)
	@nasm $(NASMFLAGS) $(GIT_NASM_DEFINES) $< -o $@

build/%.bin: src/miniboot32/%.nasm
	@mkdir -p $(shell dirname $@)
	@nasm $(NASMFLAGS) $(GIT_NASM_DEFINES) $< -o $@

$(IMG): $(mbr_binary_files) $(vbr_binary_files) $(stage2_binary_files) $(boottest_binary_files)
	@scripts/create-disk.sh

$(IMGZ): $(IMG)
	@gzip -9kc $(IMG) > $(IMGZ)