CC            = cc
CXX           = c++
CFLAGS        = -march=native -O2 -std=c11 -Wall -Wextra
CXXFLAGS      = -march=native -O2 -O2 -Wall -Wextra
INCLUDES      = -I. -Ideps/include

LLAMA_TAG     = b10107
LLAMA_URL     = https://github.com/ggml-org/llama.cpp/archive/refs/tags/$(LLAMA_TAG).tar.gz
LLAMA_TAR     = deps/llama-$(LLAMA_TAG).tar.gz
LLAMA_SRC_DIR = deps/llama.cpp-src
LLAMA_BUILD   = $(LLAMA_SRC_DIR)/build

STATIC_LIBS   = deps/lib/libllama.a \
                deps/lib/libggml.a \
                deps/lib/libggml-cpu.a \

# System flags required for static linking llama on OpenBSD
SYS_LIBS      = -static -pthread -lm -lc++ -lc++abi

TARGET        = lexd
SRC           = llm.c main.c
OBJS          = $(SRC:.c=.o)

# Standard tools and target directory
BINDIR        = /usr/local/bin
RCDIR         = /etc/rc.d
VARDIR        = /var/$(TARGET)
INSTALL       = install
INSTALL_PROGRAM = $(INSTALL) -m 755
INSTALL_SCRIPT  = $(INSTALL) -m 555
MKDIR_P       = mkdir -p

# Service user configuration
SERVICE_USER    = _lexd
SERVICE_GROUP   = _lexd

.PHONY: all clean distclean

all: $(TARGET)

# Explicit link order: libllama -> libggml-cpu -> libggml -> libggml-base
$(TARGET): deps/lib/libllama.a $(OBJS)
	$(CXX) $(CXXFLAGS) $(OBJS) \
		-Wl,--start-group \
		deps/lib/libllama.a \
		deps/lib/libggml-cpu.a \
		deps/lib/libggml.a \
		deps/lib/libggml-base.a \
		-Wl,--end-group \
		$(SYS_LIBS) -o $@

# BSD suffix rule: compiles any .c file into .o
.c.o:
	$(CC) $(CFLAGS) $(INCLUDES) -c $< -o $@

# Rebuild objects if the shared header changes
$(OBJS): llm.h

# Download llama source and build statically
deps/lib/libllama.a deps/lib/libggml.a deps/lib/libggml-cpu.a:
	@mkdir -p deps/lib deps/include
	@echo "===> Downloading llama.cpp $(LLAMA_TAG) source..."
	ftp -o $(LLAMA_TAR) $(LLAMA_URL)

	@echo "===> Extracting source archive..."
	tar -xzf $(LLAMA_TAR) -C deps
	rm -rf $(LLAMA_SRC_DIR)
	mv deps/llama.cpp-$(LLAMA_TAG) $(LLAMA_SRC_DIR)
	rm -f $(LLAMA_TAR)
	
	@echo "===> Compiling llama static archives..."
	cmake -S $(LLAMA_SRC_DIR) -B $(LLAMA_BUILD) \
		-DCMAKE_BUILD_TYPE=Release \
		-DBUILD_SHARED_LIBS=OFF \
		-DGGML_OPENMP=OFF \
		-DGGML_VULKAN=OFF \
		-DLLAMA_BUILD_APP=OFF \
		-DLLAMA_BUILD_COMMON=OFF \
		-DLLAMA_BUILD_TESTS=OFF \
        -DLLAMA_BUILD_UI=OFF \
		-DLLAMA_BUILD_EXAMPLES=OFF \
		-DLLAMA_BUILD_SERVER=OFF \
		-DLLAMA_BUILD_TOOLS=OFF

	cmake --build $(LLAMA_BUILD) --config Release -j$$(sysctl -n hw.ncpu)

	@echo "===> Installing .a files and headers into deps/..."
	find $(LLAMA_BUILD) -type f -name "*.a" -exec cp {} deps/lib/ \;
	cp -R $(LLAMA_SRC_DIR)/include/* deps/include/
	cp -R $(LLAMA_SRC_DIR)/ggml/include/* deps/include/

	@echo "===> Cleaning up build directory..."
	rm -rf $(LLAMA_SRC_DIR)

install-user:
	@if ! id -u $(SERVICE_USER) >/dev/null 2>&1; then \
		echo "===> Creating service user..."; \
		groupadd $(SERVICE_GROUP) 2>/dev/null || true; \
		useradd -g $(SERVICE_GROUP) -s /sbin/nologin -m -c "lexd daemon user" $(SERVICE_USER); \
	fi

install: $(TARGET) install-user
	@$(MKDIR_P) $(BINDIR)
	@echo "===> Installing executable to $(BINDIR)/$(TARGET)..."
	@$(INSTALL_PROGRAM) $(TARGET) $(BINDIR)/$(TARGET)
	@echo "===> Installing RC script to $(DESTDIR)$(RCDIR)/$(TARGET)..."
	@$(MKDIR_P) $(RCDIR)
	@$(INSTALL_SCRIPT) $(TARGET).rc $(RCDIR)/$(TARGET)
	@echo "===> Creating data directory $(VARDIR)..."
	@$(MKDIR_P) $(VARDIR)
	@chown $(SERVICE_USER):$(SERVICE_GROUP) $(VARDIR)
	@chmod 750 $(VARDIR)
	@echo "===> Installation complete."

uninstall:
	@echo "===> Stopping service..."
	@-rcctl stop $(TARGET) 2>/dev/null || true
	@rm -f $(BINDIR)/$(TARGET)
	@rm -f $(RCDIR)/$(TARGET)
	@echo "Uninstall complete."
	@echo "Note: The data directory and service accounts were preserved."
	@echo "To remove all remaining data, run:"
	@echo "  # rm -rf $(VARDIR)"
	@echo "  # userdel -r $(SERVICE_USER)"
	@echo "  # groupdel $(SERVICE_GROUP)"

clean:
	rm -f $(TARGET) $(OBJS)
	
distclean: clean
	rm -rf deps