################
# Prepare pass #
################

$(eval $(call omk_pass_template,prepare-pass))

###
# Name of the prepared rule.  This name is used as prefix of variable
# names in .omk.inc and is based on the first target
omk_inc_rule = $(firstword $(1:$(OUTPUT_DIR)/%=%))

# The name of .omk.inc file is derived from $(omk_inc_rule) and
# depends whether the target is under _build or elsewhere.
omk_inc_file = $(if $(filter $(BUILD_DIR_NAME)%,$(omk_inc_rule)),\
		    $(OMK_WORK_DIR)/$(notdir $(omk_inc_rule)).omk.inc,\
		    $(OMK_WORK_DIR)/$(subst /,_,$(omk_inc_rule)).omk.inc)

target_omk_file = $(OMK_WORK_DIR)/$(notdir $(1)).target.omk

# >'< substitution is for echo to work,
# >$< substitution to preserve $ when reloading .omk.inc file
subst-cmd = $(subst \#,\\\#,$(subst $$,$$$$,$(call escsq,$(1))))

###
# prepare_rule is used to generate .omk.inc files during prepare-pass.
# All paths in this file should be relative to $(OUTPUT_DIR)
# Usage: $(eval $(call prepare_rule,<targets>,<deps>,<msg>,<cmd>))
define prepare_rule
prepare-pass-local: $(omk_inc_file)

$(omk_inc_file): FORCE
#TODO remove the next line
	@echo "  PREP    "$$(call strip_out,$$@); \
	    echo 'prepared_rules += $(omk_inc_rule)' > $$@.tmp; \
	    echo '$(omk_inc_rule)_targets = $$(call strip_out,$(1))' >> $$@.tmp; \
	    echo '$(omk_inc_rule)_deps += $$(call strip_out,$(2))' >> $$@.tmp; \
	    echo '$(omk_inc_rule)_msg = $(3)' >> $$@.tmp; \
	    echo '$(omk_inc_rule)_cmd = $(call subst-cmd,$(4))' >> $$@.tmp; \
	if cmp -s $$@.tmp $$@; then rm $$@.tmp; else mv $$@.tmp $$@; fi
endef

###
# prepare_rule_goal - same as prepare rules but the target is put
# as dependency to the default goal, which causes it to be built
# upon calling make
define prepare_rule_goal
$(call prepare_rule,$(1),$(2),$(3),$(4))
prepared_goals += $(call strip_out,$(1))
endef

prepare-pass-local: $(OMK_WORK_DIR)/__goals.omk.inc
$(OMK_WORK_DIR)/__goals.omk.inc: FORCE
	$(Q)echo 'omk_goals += $(prepared_goals)' > $@.tmp; \
	    if cmp -s $@.tmp $@; then rm $@.tmp; else mv $@.tmp $@; fi