#
# Copyright (c) ZeroC, Inc. All rights reserved.
#

#
# If multiple versions of Python are installed and you want a specific
# version to be used for building the Ice extension, set PYTHON to the
# location of the python interpreter.
#
PYTHON              ?= python3

# ----------------------------------------------------------------------
# Don't change anything below this line!
# ----------------------------------------------------------------------

-include        $(lang_srcdir)/config/Make.rules.$(os)

# PYTHON must be set to a value that has a corresponding PYTHON-config
python-config := $(PYTHON)-config

ifeq ($(os),Linux)
   cppflags   := $(filter-out -Wredundant-decls,$(cppflags))
endif

python_cppflags         := $(or $(PYTHON_CPPFLAGS),$(shell $(python-config) --cflags))
python_ldflags          := $(or $(PYTHON_LDLFLAGS),$(shell $(python-config) --ldflags))

# Use .so as default value --extension-suffix is not supported by python-config in all platforms
python_extsuffix        := $(or $(shell $(python-config) --extension-suffix 2> /dev/null),.so)

# As of Python 3.8 the python library is not included in the ldflags
# This is also the same behavior used by pip
allow-undefined-symbols := yes

# Debian packaging complains if these libraries are included
ifneq ($(filter debian ubuntu,$(linux_id)),)
python_ldflags          := $(filter-out -lpython% -ldl -lutil,$(python_ldflags))
endif

ifeq ($(os),AIX)
# We use an attribute (not an export file) to export the entry point
link-with-python-exp   := -Wl,-bE:Modules/python.exp
python_ldflags         := $(filter-out $(link-with-python-exp),$(python_ldflags))

# $(call mkshlib,$1=target,$2=objects,$3=libname,$4=version,$5=soversion,$6=ldflags,$7=platform)
mkshlib                = $(or $($7_cxx),$(CXX)) -shared -o $1 $2 $6
endif

ifneq ($(OPTIMIZE),yes)
# Remove optimization options if building debug build
python_cppflags         := $(filter-out -O% -DNDEBUG -Wp$(comma)-D_FORTIFY_SOURCE=%,$(python_cppflags))
endif

# Remove the -Wstrict-prototypes option which is not valid with C++ and
# -Wunreachable-code which is causing a compilation error with Slice/Parser.cpp
python_cppflags         := $(filter-out -Wunreachable-code -Wstrict-prototypes,$(python_cppflags)) -Wno-missing-field-initializers

#
# Python installation directory
#
install_pythondir       = $(or $(PYTHON_INSTALLDIR),$(shell $(PYTHON) $(lang_srcdir)/config/install_dir $(prefix)))

#
# Rules to build a python module. We just compute the name of the python module
# and delegate to make-shared-module.
#
mkpymodulename                   ?= $(patsubst lib%.so,%$(python_extsuffix),$(call mkshlibname,$(1)))
make-shared-python-module        = $(call make-shared-module,$(call mkpymodulename,$1),$2,$3,$4,$5,$6,$7,$8,$9)
get-shared-python-module-targets = $(call get-shared-module-targets,$(call mkpymodulename,$1),$2,$3,$4)
install-shared-python-module     = $(call install-shared-module,$(call mkpymodulename,$1),$2,$3,$4,$5)

$(DESTDIR)$(install_pythondir):
	$(Q)$(MKDIR) -p $@
installdirs += $(install_pythondir)

#
# $(call make-python-package,$1=slicedir,$2=generateddir,$3=package,$4=sliceflags)
#
# Compile slice files from $(slicedir)/<package> to python/<package>.
#
define make-python-package

$2/$3/.depend/%.ice.d: | $2/$3/.depend ;

$2/$3/.depend:
	$(Q)$(MKDIR) -p $$@

.PRECIOUS: $2/$3/.depend/%.ice.d

ifeq ($(filter %clean,$(MAKECMDGOALS)),)
    # Include the dependencies
    -include $(addprefix $2/.depend/,$(call source-to-dependency,$(wildcard $1/$3/*.ice)))
endif

$$(eval $$(call make-python-slice,$1,$2,$3,,$4))

distclean clean::
	$(E) "Cleaning package $3"
	$(Q)$(RM) -r $2/$3/.depend
	$(Q)$(if $(findstring --no-package,$4),,$(RM) $2/$3/__init__.py)
	$(Q)$(RM) $(patsubst $1/$3/%.ice,$2/$3/%_ice.py,$(wildcard $1/$3/*.ice))

generate-srcs srcs all:: $(patsubst $1/$3/%.ice,$2/$3/%_ice.py,$(wildcard $1/$3/*.ice))

$$(eval $$(call install-data-files,$(patsubst $1/$3/%.ice,$2/$3/%_ice.py,$(wildcard $1/$3/*.ice)),$2,$(install_pythondir),install))

# If we also generate a package directory with an __init__.py, install it.
ifeq ($(findstring --no-package,$4),)
    $$(eval $$(call install-data-files,$2/$3/__init__.py,$2,$(install_pythondir),install))
endif

endef

#
# $(call make-python-slice,$1=slicedir,$2=generateddir,$3=package,$4=file,$5=sliceflags)
#
define make-python-slice

$2/$3/$(or $4,%)_ice.py: $1/$3/$(or $4,%).ice $2/$3/.depend/$(or $4,%).ice.d $(slice2py_path)
	$(E) "Compiling $$<"
	$(Q)$(slice2py_path) -I$1 --output-dir $2 $5 --depend $$< > $2/$3/.depend/$(or $4,$$(*F)).ice.d
	$(Q)$(slice2py_path) -I$1 --output-dir $2 --checksum $5 $$<

endef