all: lua-5.1-try lua-5.2-try

install: lua-5.1-try-install lua-5.2-try-install

ifeq ($(strip $(shell which pkg-config > /dev/null || echo NONE)),NONE)
  $(error This makefile requires pkg-config)
endif

ifeq ($(strip $(shell which $(CC) > /dev/null || echo NONE)),NONE)
  $(info Luxio: Hmm, CC make variable contains nonsense.  Overriding to gcc.)
  CC := gcc
endif

# This isn't nice.  Find a nice way.
HOST_OS := $(shell uname -s)

ifneq ($(findstring $(HOST_OS),Linux NetBSD GNU/kFreeBSD),)
  # These operating systems require a seperate Real Time library
  EXTRA_LIBS := -lrt
else
  EXTRA_LIBS :=
endif

NAKED_LUA_VER := $(shell (pkg-config --exists lua && \
                          pkg-config --modversion lua || \
			  pkg-config --variable V lua) | cut -d. -f1-2)

# fine appropriate Lua interpreter
LUA_REPL := $(shell (which lua5.1 > /dev/null 2>&1 && echo lua5.1) || \
                    (which lua-5.1 > /dev/null 2>&1 && echo lua-5.1) || \
                    (which lua51  > /dev/null 2>&1 && echo lua51) || \
                    (lua -e"print(_VERSION)" | grep -q 5.1 && echo lua) || \
                    (which lua-5.2 > /dev/null 2>&1 && echo lua-5.2) || \
                    (which lua52 > /dev/null 2>&1 && echo lua52))

# find appropriate Lua libraries
LUA51_PKG := $(shell (pkg-config --exists lua5.1 && echo lua5.1) || \
                     (pkg-config --exists lua-5.1 && echo lua-5.1) || \
		     (pkg-config --exists lua51 && echo lua51) || \
                     (echo "NONE"))


LUA51_PKG := $(strip $(LUA51_PKG))

ifeq ($(LUA51_PKG),NONE)
  ifeq ($(NAKED_LUA_VER),5.1)
    LUA51_PKG := lua
  endif
endif

ifneq ($(LUA51_PKG),NONE)
  $(info Luxio: Lua 5.1 package name on this system is $(LUA51_PKG))
  LUA51_HAS_MODINST := $(shell test x`pkg-config --variable INSTALL_LMOD $(LUA51_PKG)` != x && echo YES)
  LUA51_INC := $(shell pkg-config --cflags $(LUA51_PKG))
  LUA51_LIB := $(shell pkg-config --libs $(LUA51_PKG))
  ifeq ($(LUA51_HAS_MODINST),)
    LOCAL := YES
  endif
  ifeq ($(LOCAL),)
    LUA51_LMOD_INST := $(shell pkg-config --variable=INSTALL_LMOD $(LUA51_PKG))
    LUA51_CMOD_INST := $(shell pkg-config --variable=INSTALL_CMOD $(LUA51_PKG))
  else
    LUA51_LMOD_INST := /usr/local/share/lua/5.1
    LUA51_CMOD_INST := /usr/local/lib/lua/5.1
  endif
  lua-5.1-try: lua-5.1
  lua-5.1-try-install: lua-5.1-install
else
lua-5.1-try:
	@echo Luxio: Lua 5.1 could not be found, so luxio was not built for it.
lua-5.1-try-install:
	@echo Luxio: Lua 5.1 could not be found, so luxio was not installed for it.
endif

LUA52_PKG := $(shell (pkg-config --exists lua5.2 && echo lua5.2) || \
                     (pkg-config --exists lua-5.2 && echo lua-5.2) || \
                     (pkg-config --exists lua52 && echo lua52) || \
                     (echo "NONE")) 

LUA52_PKG := $(strip $(LUA52_PKG))

ifeq ($(LUA52_PKG),NONE)
  ifeq ($(NAKED_LUA_VER),5.2)
    LUA52_PKG := lua
  endif
endif

ifneq ($(LUA52_PKG),NONE)
  $(info Luxio: Lua 5.2 package name on this system is $(LUA52_PKG))
  LUA52_HAS_MODINST := $(shell test x`pkg-config --variable INSTALL_LMOD $(LUA52_PKG)` != x && echo YES)
  LUA52_INC := $(shell pkg-config --cflags $(LUA52_PKG))
  LUA52_LIB := $(shell pkg-config --libs $(LUA52_PKG))
  ifeq ($(LUA52_HAS_MODINST),)
    LOCAL := YES
  endif
  ifeq ($(LOCAL),)
    LUA52_LMOD_INST := $(shell pkg-config --variable=INSTALL_LMOD $(LUA52_PKG))
    LUA52_CMOD_INST := $(shell pkg-config --variable=INSTALL_CMOD $(LUA52_PKG))
  else
    LUA52_LMOD_INST := /usr/local/share/lua/5.2
    LUA52_CMOD_INST := /usr/local/lib/lua/5.2
  endif
  lua-5.2-try: lua-5.2
  lua-5.2-try-install: lua-5.2-install
else
lua-5.2-try:
	@echo Luxio: Lua 5.2 could not be found, so luxio was not built for it.
lua-5.2-try-install:
	@echo Luxio: Lua 5.2 could not be found, so luxio was not installed for it.
endif


CFLAGS ?= -O2 -Wall
INSTALL := /usr/bin/install

LUALIBS := $(patsubst %,luxio/%.lua, \
	event simple subprocess)


clean:
	$(RM) *.so *.o luxio_constants.h luxio-5.1 luxio-5.2

luxio_constants.h: luxio_constants.h.in const-proc.lua
	$(LUA_REPL) ./const-proc.lua < $^ > $@

lua-5.1: luxio-5.1.so luxio-5.1
	ln -s -f luxio-5.1.so luxio.so

lua-5.1-install: lua-5.1
	$(INSTALL) -d $(DESTDIR)$(LUA51_CMOD_INST)
	$(INSTALL) -m 755 luxio-5.1.so $(DESTDIR)$(LUA51_CMOD_INST)/luxio.so
	$(INSTALL) -d $(DESTDIR)$(LUA51_LMOD_INST)/luxio
	$(INSTALL) -m 644 $(LUALIBS) $(DESTDIR)$(LUA51_LMOD_INST)/luxio/
	$(INSTALL) -d $(DESTDIR)$(PREFIX)/bin
	$(INSTALL) luxio-5.1 $(DESTDIR)$(PREFIX)/bin/luxio-5.1

luxio-5.1.so: luxio-5.1.o
	$(CC) $(LDFLAGS) -shared $(EXTRA_LIBS) -o luxio-5.1.so $^ $(LUA51_LIB)

luxio-5.1: lua-5.1.c luxio-5.1.o
	$(CC) -o luxio-5.1 $(CFLAGS) $(LUA51_INC) $(LDFLAGS) $(EXTRA_LIBS) lua-5.1.c luxio-5.1.o $(LUA51_LIB)

lua-5.2: luxio-5.2.so luxio-5.2
	ln -s -f luxio-5.2.so luxio.so

lua-5.2-install: lua-5.2
	$(INSTALL) -d $(DESTDIR)$(LUA52_CMOD_INST)
	$(INSTALL) -m 755 luxio-5.2.so $(DESTDIR)$(LUA52_CMOD_INST)/luxio.so
	$(INSTALL) -d $(DESTDIR)$(LUA52_LMOD_INST)/luxio
	$(INSTALL) -m 644 $(LUALIBS) $(DESTDIR)$(LUA52_LMOD_INST)/luxio/
	$(INSTALL) -d $(DESTDIR)$(PREFIX)/bin
	$(INSTALL) luxio-5.2 $(DESTDIR)$(PREFIX)/bin/luxio-5.2

luxio-5.2.so: luxio-5.2.o
	$(CC) $(LDFLAGS) -shared $(EXTRA_LIBS) -o luxio-5.2.so $^ $(LUA52_LIB)

luxio-5.2: lua-5.2.c luxio-5.2.o
	$(CC) -o luxio-5.2 $(CFLAGS) $(LDFLAGS) $(EXTRA_LIBS) $(LUA52_INC) lua-5.2.c luxio-5.2.o $(LUA52_LIB)

###

luxio-5.1.o: luxio.c luxio_constants.h 
	$(CC) $(CFLAGS) -fPIC $(LUA51_INC) -c $< -o $@

luxio-5.2.o: luxio.c luxio_constants.h
	$(CC) $(CFLAGS) -fPIC $(LUA52_INC) -c $< -o $@