CC ?= gcc
DEBUG ?= 0

CFLAGS = -Wall -Werror -Wextra -Wpedantic -std=c99 -Ofast \
-D_POSIX_C_SOURCE=200809L

ifeq ($(DEBUG), 1)
	CFLAGS += -g -DDEBUG
endif

SRCDIR = ./src
INCDIR = ./include
OBJDIR = ./obj
BINDIR = ./bin

SRC = $(wildcard $(SRCDIR)/*.c)
OBJ = $(SRC:$(SRCDIR)/%.c=$(OBJDIR)/%.o)
DEP = $(OBJ:.o=.d)

PROGNAME_RELEASE = polonium
PROGNAME_DEBUG = polonium_debug

ifeq ($(DEBUG), 1)
	EXECUTABLE = $(PROGNAME_DEBUG)
else
	EXECUTABLE = $(PROGNAME_RELEASE)
endif

EXECPATH = $(BINDIR)/$(EXECUTABLE)
EXECPATH_RELEASE = $(BINDIR)/$(PROGNAME_RELEASE)
EXECPATH_DEBUG = $(BINDIR)/$(PROGNAME_DEBUG)

all: $(EXECPATH)

$(EXECPATH): $(OBJ)
	@mkdir -p $(@D)
	$(CC) $(CFLAGS) $^ -o $@
ifeq ($(DEBUG), 0)
	strip $@*
endif

-include $(DEP)

$(OBJDIR)/%.o: $(SRCDIR)/%.c
	@mkdir -p $(@D)
	$(CC) $(CFLAGS) -I$(INCDIR) -MMD -MP -c $< -o $@

define rmfiles_if_exist
	@for file in $1; do \
		if [ -e $$file ]; then \
			echo "Removing file $$file"; \
			rm $$file; \
		fi; \
	done
endef

define rmdir_if_empty
	@if [ -d "$1" ]; then \
		if [ -z "$$(find "$1" -mindepth 1 -maxdepth 1 -print -quit)" ]; then \
			echo "Removing empty directory $1"; \
			rm -r $1; \
		fi; \
	fi
endef

clean:
	$(call rmfiles_if_exist,$(EXECPATH_RELEASE) $(EXECPATH_DEBUG) $(DEP) $(OBJ))
	$(call rmdir_if_empty,$(BINDIR))
	$(call rmdir_if_empty,$(OBJDIR))

.PHONY: all clean