# DOS (DJGPP) build rules: JoeyLib's library for DOS, and programRules, the
# DOS rules for one program, which make/programs.mk instantiates for every
# program (a project reaches both through make/project.mk). JoeyLib's own
# examples are at the end.

PLATFORM := dos
include $(dir $(lastword $(MAKEFILE_LIST)))/common.mk

$(call requireTool,$(DOS_CC),toolchain:dos)
$(call requireTool,$(DOS_AS),toolchain:dos)
$(call requireTool,$(DOS_CWSDSTUB),toolchain:dos)
$(call requireTool,$(LIBXMP_DIR)/include/libxmp-lite/xmp.h,toolchain:dos)

# -fomit-frame-pointer: flag parity with the ST/Amiga CFLAGS (both had
# it; DOS never did). Frees EBP for allocation in the hot loops under
# DOSBox's per-instruction-charged core (perf-hunt-2 rank 2).
# so flag experiments never edit a tracked file (perf-hunt-2 rank 17).
CFLAGS  := $(COMMON_CFLAGS) -march=i386 -m32 -fomit-frame-pointer -I$(SRC_DIR)/dos -I$(SRC_X86) -I$(LIBXMP_DIR)/include -MMD -MP
ASFLAGS := -f coff

# libxmp-lite (MIT, libxmp.org) -- 4-channel-Protracker-and-friends
# replayer + SMIX SFX overlay. Installed by ./install.sh
# (LIBXMP_DIR, from config.mk). Built as a static archive that the DOS
# audio HAL links against.
LIBXMP_SRC     := $(filter-out %/win32.c, $(wildcard $(LIBXMP_DIR)/src/*.c) $(wildcard $(LIBXMP_DIR)/src/loaders/*.c))
LIBXMP_OBJDIR  := $(BUILD)/obj/libxmp-lite
LIBXMP_OBJS    := $(patsubst $(LIBXMP_DIR)/src/%.c,$(LIBXMP_OBJDIR)/%.o,$(LIBXMP_SRC))
LIBXMP_AR      := $(LIBDIR)/libxmplite.a
LIBXMP_CFLAGS  := -DJOEY_LIBXMP_LITE -DLIBXMP_CORE_PLAYER -DHAVE_FNMATCH=0 -I$(LIBXMP_DIR)/include -I$(LIBXMP_DIR)/include/libxmp-lite -I$(LIBXMP_DIR)/src -Wno-error -w

# The x86 code DOS shares with DVX (the sprite emitter, the whole-map tile
# walker, the set-1 scan code table) lives in src/x86 and builds into obj/x86;
# only the CPU-independent sprite dispatch stays in src/codegen.
PORT_C_SRCS := $(wildcard $(SRC_DIR)/dos/*.c)
PORT_S_SRCS := $(wildcard $(SRC_DIR)/dos/*.asm)
X86_C_SRCS  := $(wildcard $(SRC_X86)/*.c)
CODEGEN_DIR := $(REPO_DIR)/src/codegen

LIB_OBJS := \
    $(patsubst $(SRC_CORE)/%.c,$(BUILD)/obj/core/%.o,$(CORE_C_SRCS)) \
    $(patsubst $(SRC_DIR)/generic/%.c,$(BUILD)/obj/generic/%.o,$(GENERIC_C_SRCS)) \
    $(patsubst $(SRC_DIR)/dos/%.c,$(BUILD)/obj/port/%.o,$(PORT_C_SRCS)) \
    $(patsubst $(SRC_DIR)/dos/%.asm,$(BUILD)/obj/port/%.o,$(PORT_S_SRCS)) \
    $(patsubst $(SRC_X86)/%.c,$(BUILD)/obj/x86/%.o,$(X86_C_SRCS)) \
    $(BUILD)/obj/codegen/spriteCompile.o \
    $(BUILD)/obj/codegen/spriteStage.o

LIB := $(LIBDIR)/libjoey.a

$(BUILD)/obj/core/%.o: $(SRC_CORE)/%.c
	@mkdir -p $(dir $@)
	$(DOS_CC) $(CFLAGS) -c $< -o $@

$(BUILD)/obj/generic/%.o: $(SRC_DIR)/generic/%.c
	@mkdir -p $(dir $@)
	$(DOS_CC) $(CFLAGS) -c $< -o $@

$(BUILD)/obj/port/%.o: $(SRC_DIR)/dos/%.c
	@mkdir -p $(dir $@)
	$(DOS_CC) $(CFLAGS) -I$(CODEGEN_DIR) -c $< -o $@

$(BUILD)/obj/port/%.o: $(SRC_DIR)/dos/%.asm
	@mkdir -p $(dir $@)
	$(DOS_AS) $(ASFLAGS) $< -o $@

$(BUILD)/obj/x86/%.o: $(SRC_X86)/%.c
	@mkdir -p $(dir $@)
	$(DOS_CC) $(CFLAGS) -I$(CODEGEN_DIR) -c $< -o $@

$(BUILD)/obj/codegen/%.o: $(CODEGEN_DIR)/%.c
	@mkdir -p $(dir $@)
	$(DOS_CC) $(CFLAGS) -I$(CODEGEN_DIR) -c $< -o $@

# Archived from scratch, so the members -- and every program's layout --
# follow LIB_OBJS rather than the order earlier builds added them in.
$(LIB): $(LIB_OBJS)
	@mkdir -p $(dir $@)
	rm -f $@
	$(DOS_AR) rcs $@ $^

$(LIBXMP_OBJDIR)/%.o: $(LIBXMP_DIR)/src/%.c
	@mkdir -p $(dir $@)
	$(DOS_CC) $(CFLAGS) $(LIBXMP_CFLAGS) -c $< -o $@

$(LIBXMP_AR): $(LIBXMP_OBJS)
	@mkdir -p $(dir $@)
	rm -f $@
	$(DOS_AR) rcs $@ $^

# Pull in per-object header-dependency files generated by gcc -MMD/-MP.
# Without this, editing a header (e.g. surfaceInternal.h) doesn't rebuild
# the .c files that include it, leaving a frankenstein binary where
# different TUs see different struct layouts.
-include $(LIB_OBJS:.o=.d)

# ---- programs -----------------------------------------------------------------
# A program is NAME.EXE, in bin/ or in its own bin/NAME/ with its DATA beside
# it (JoeyLib's install convention), where DOSBox's C: (bin/ or the folder)
# finds both.
PROGRAM_EXT     := .EXE
PROGRAM_FOLDERS := yes

# One program, $(1) its id: compiled and linked in one step with the library
# and libxmp-lite, then given the CWSDPMI DPMI server, so the .EXE needs no
# CWSDPMI.EXE beside it. gcc's -MMD leaves NAME.d beside it, for header edits.
define programRules
$(call programBin,$(1)): $(call programVar,$(1),SRCS) $(LIB) $(LIBXMP_AR)
	@mkdir -p $$(dir $$@)
	$(DOS_CC) $(CFLAGS) $(call programVar,$(1),CFLAGS) $(call programVar,$(1),SRCS) $(LIB) $(LIBXMP_AR) -o $$@ $(call programVar,$(1),LDFLAGS)
	$(DOS_EMBED_DPMI) $$@
-include $(basename $(call programBin,$(1))).d
endef

# ---- JoeyLib's own build: its examples ------------------------------------------
ifndef JOEY_PROJECT

include $(REPO_DIR)/make/examples.mk
include $(REPO_DIR)/make/programs.mk

.DEFAULT_GOAL := all
.PHONY: all dos clean-dos clean
all dos: $(LIB) $(LIBXMP_AR) programs

clean-dos:
	rm -rf $(BUILD)

# `clean` as an alias for `clean-dos`. Without it a bare
# `make -f make/dos.mk clean` FAILS -- and with stderr discarded that
# looks like success while leaving stale objects the next build links.
clean: clean-dos

endif