# engines/src/fortran/Makefile
# 编译 DLL 到 engines/release/（主程序通过 ctypes 直接调用）

FC      = gfortran
FFLAGS  = -O3 -march=native -Wall -Wextra
LIB_SRC = dynamics_lib.f90

UNAME_S := $(shell uname -s 2>/dev/null || echo Windows)

# Windows 检测：Msys2/MINGW 也视为 Windows
IS_WINDOWS := $(findstring MINGW,$(UNAME_S))
ifneq ($(IS_WINDOWS),)
  UNAME_S := Windows
endif
IS_WINDOWS := $(findstring MSYS,$(UNAME_S))
ifneq ($(IS_WINDOWS),)
  UNAME_S := Windows
endif

# DLL 输出到 engines/release/
DLL_DIR = ../../release

ifeq ($(UNAME_S),Linux)
  DLL_TARGET = $(DLL_DIR)/dynamics_f90.so
  DLL_FLAGS  = -shared -fPIC
else ifeq ($(UNAME_S),Darwin)
  DLL_TARGET = $(DLL_DIR)/dynamics_f90.dylib
  DLL_FLAGS  = -dynamiclib
else
  # Windows: 完全静态链接，避免依赖 libgfortran-5.dll
  DLL_TARGET = $(DLL_DIR)/dynamics_f90.dll
  DLL_FLAGS  = -shared -fPIC -static
endif

.PHONY: all dll clean

all: dll

dll: $(DLL_TARGET)

$(DLL_TARGET): $(LIB_SRC) | $(DLL_DIR)
	$(FC) $(FFLAGS) $(DLL_FLAGS) -o $@ $(LIB_SRC)
	@echo "  === Fortran DLL built: $@ ==="

$(DLL_DIR):
	mkdir -p $(DLL_DIR)

clean:
	rm -f $(DLL_TARGET)