LIB_NAME      ?= weaver
BUILD_DIR     ?= build
SRC_DIR       ?= src
INCLUDE_DIRS  := include src/include

MODE          ?= debug

RELEASE_OPT   ?= 2
CLINE_SIZE    ?= 64

CXX           ?= clang++
AR            ?= ar
ARFLAGS       := rcs

SRCS := $(shell find $(SRC_DIR) -name '*.cc')
OBJS := $(patsubst $(SRC_DIR)/%.cc,$(BUILD_DIR)/%.o,$(SRCS))
DEPS := $(OBJS:.o=.d)

INCLUDES := $(addprefix -I,$(INCLUDE_DIRS))

WARN_FLAGS := \
	-Wall \
	-Wextra \
	-Wpedantic \
	-Werror

COMMON_CXXFLAGS := \
	-std=c++20 \
	-MMD -MP \
	-flto \
	--param=destructive-interference-size=$(CLINE_SIZE) \
	$(WARN_FLAGS) \
	$(INCLUDES)

DEBUG_CXXFLAGS := \
	-O0 \
	-g \
	-fsanitize=thread \
	-fno-omit-frame-pointer

RELEASE_CXXFLAGS := \
	-O$(RELEASE_OPT) \
	-DNDEBUG

ifeq ($(MODE),debug)
	CXXFLAGS := $(COMMON_CXXFLAGS) $(DEBUG_CXXFLAGS)
else ifeq ($(MODE),release)
	CXXFLAGS := $(COMMON_CXXFLAGS) $(RELEASE_CXXFLAGS)
else
	$(error Unknown MODE '$(MODE)'; use MODE=debug or MODE=release)
endif

LIB := $(BUILD_DIR)/lib$(LIB_NAME).a

.PHONY: all clean

all: $(LIB)

$(LIB): $(OBJS)
	@mkdir -p $(dir $@/bin)
	$(AR) $(ARFLAGS) $@/bin $^

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

-include $(DEPS)

clean:
	rm -rf $(BUILD_DIR)