CXX ?= clang++
CXXFLAGS ?= -std=c++17 -O2 -Wall -Wextra -pedantic
CPPFLAGS ?= -I.
ASFLAGS ?=
DEBUG ?= 0

ifeq ($(DEBUG),1)
CXXFLAGS := $(filter-out -O2,$(CXXFLAGS))
CXXFLAGS += -O0 -g
ASFLAGS += -g
endif

TARGET := bin/img_tool
BUILD_DIR := build
CPP_SRCS := src/main.cpp
ASM_SRCS := asm/to_grayscale.s asm/blur.s asm/detect_edges.s
OBJS := $(addprefix $(BUILD_DIR)/,$(CPP_SRCS:.cpp=.o)) $(addprefix $(BUILD_DIR)/,$(ASM_SRCS:.s=.o))

.PHONY: all clean debug

all: $(TARGET)

$(TARGET): $(OBJS)
	@mkdir -p $(dir $@)
	$(CXX) $(OBJS) -o $@

$(BUILD_DIR)/%.o: %.cpp
	@mkdir -p $(dir $@)
	$(CXX) $(CPPFLAGS) $(CXXFLAGS) -c $< -o $@

$(BUILD_DIR)/%.o: %.s
	@mkdir -p $(dir $@)
	$(CXX) $(CPPFLAGS) $(ASFLAGS) -c $< -o $@

clean:
	rm -rf $(BUILD_DIR) $(TARGET)

debug:
	$(MAKE) clean
	$(MAKE) DEBUG=1 all