# Copyright (c) 2013-2016, Loïc Hoguin <essen@ninenines.eu>
# This file is part of erlang.mk and subject to the terms of the ISC License.

# Configuration.

DTL_FULL_PATH ?=
DTL_PATH ?= templates/
DTL_PREFIX ?=
DTL_SUFFIX ?= _dtl
DTL_OPTS ?=

# Verbosity.

dtl_verbose_0 = @echo " DTL   " $(filter %.dtl,$(?F));
dtl_verbose = $(dtl_verbose_$(V))

# Core targets.

DTL_PATH := $(abspath $(DTL_PATH))
DTL_FILES := $(sort $(call core_find,$(DTL_PATH),*.dtl))

ifneq ($(DTL_FILES),)

DTL_NAMES   = $(addprefix $(DTL_PREFIX),$(addsuffix $(DTL_SUFFIX),$(DTL_FILES:$(DTL_PATH)/%.dtl=%)))
DTL_MODULES = $(if $(DTL_FULL_PATH),$(subst /,_,$(DTL_NAMES)),$(notdir $(DTL_NAMES)))
BEAM_FILES += $(addsuffix .beam,$(addprefix ebin/,$(DTL_MODULES)))

ifneq ($(words $(DTL_FILES)),0)
# Rebuild templates when the Makefile changes.
$(ERLANG_MK_TMP)/last-makefile-change-erlydtl: $(MAKEFILE_LIST) | $(ERLANG_MK_TMP)
	$(verbose) if test -f $@; then \
		touch $(DTL_FILES); \
	fi
	$(verbose) touch $@

ebin/$(PROJECT).app:: $(ERLANG_MK_TMP)/last-makefile-change-erlydtl
endif

define erlydtl_compile.erl
	[begin
		Module0 = case "$(strip $(DTL_FULL_PATH))" of
			"" ->
				filename:basename(F, ".dtl");
			_ ->
				"$(call core_native_path,$(DTL_PATH))/" ++ F2 = filename:rootname(F, ".dtl"),
				re:replace(F2, "/",  "_",  [{return, list}, global])
		end,
		Module = list_to_atom("$(DTL_PREFIX)" ++ string:to_lower(Module0) ++ "$(DTL_SUFFIX)"),
		case erlydtl:compile(F, Module, [$(DTL_OPTS)] ++ [{out_dir, "ebin/"}, return_errors]) of
			ok -> ok;
			{ok, _} -> ok
		end
	end || F <- string:tokens("$(1)", " ")],
	halt().
endef

ebin/$(PROJECT).app:: $(DTL_FILES) | ebin/
	$(if $(strip $?),\
		$(dtl_verbose) $(call erlang,$(call erlydtl_compile.erl,$(call core_native_path,$?)),\
			-pa ebin/))

endif