#
# Copyright (c) 2011, 2012, Oracle and/or its affiliates. All rights reserved.
# DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
#
# This code is free software; you can redistribute it and/or modify it
# under the terms of the GNU General Public License version 2 only, as
# published by the Free Software Foundation.  Oracle designates this
# particular file as subject to the "Classpath" exception as provided
# by Oracle in the LICENSE file that accompanied this code.
#
# This code is distributed in the hope that it will be useful, but WITHOUT
# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
# FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
# version 2 for more details (a copy is included in the LICENSE file that
# accompanied this code).
#
# You should have received a copy of the GNU General Public License version
# 2 along with this work; if not, write to the Free Software Foundation,
# Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
#
# Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
# or visit www.oracle.com if you need additional information or have any
# questions.
#

################################################################
#
# This file contains helper functions for the top-level Makefile that does
# not depend on the spec.gmk file having been read. (The purpose of this 
# file is ju to avoid cluttering the top-level Makefile.)
#
################################################################

ifndef _MAKEHELPERS_GMK
_MAKEHELPERS_GMK := 1

##############################
# Stuff to run at include time
##############################

# Find out which variables were passed explicitely on the make command line. These
# will be passed on to sub-makes, overriding spec.gmk settings.
MAKE_ARGS=$(foreach var,$(subst =command,,$(filter %=command,$(foreach var,$(.VARIABLES),$(var)=$(firstword $(origin $(var)))))),$(var)=$($(var)))

list_alt_overrides_with_origins=$(filter ALT_%=environment ALT_%=command,$(foreach var,$(.VARIABLES),$(var)=$(firstword $(origin $(var)))))
list_alt_overrides=$(subst =command,,$(subst =environment,,$(list_alt_overrides_with_origins)))

##############################
# Functions
##############################

define fatal-error
    # If the user specificed a "global" target (e.g. 'help'), do not exit but continue running
    $$(if $$(findstring help,$$(MAKECMDGOALS)),,$$(error Cannot continue))
endef

define ParseLogLevel
    ifeq ($$(origin VERBOSE),undefined)
        # Setup logging according to LOG (but only if VERBOSE is not given)
        ifeq ($$(LOG),)
            # Set LOG to "warn" as default if not set (and no VERBOSE given)
            LOG=warn
        endif
        ifeq ($$(LOG),warn)
            VERBOSE=-s
        else ifeq ($$(LOG),info)
            VERBOSE=
        else ifeq ($$(LOG),debug)
            VERBOSE=
        else ifeq ($$(LOG),trace)
            VERBOSE=-d -p
        else
            $$(info Error: LOG must be one of: warn, info, debug or trace.)
            $$(eval $$(call fatal-error))
        endif
    else
        ifneq ($$(LOG),)
            # We have both a VERBOSE and a LOG argument. This is OK only if this is a repeated call by ourselves,
            # but complain if this is the top-level make call.
            ifeq ($$(MAKELEVEL),0)
                $$(info Cannot use LOG=$$(LOG) and VERBOSE=$$(VERBOSE) at the same time. Choose one.)
                $$(eval $$(call fatal-error))
            endif
        endif
    endif
endef

# TODO: Fix duplication in MakeBase.gmk
define SetupLogging
    ifneq ($(findstring $(LOG),debug trace),)
        # Shell redefinition trick inspired by http://www.cmcrossroads.com/ask-mr-make/6535-tracing-rule-execution-in-gnu-make
        OLD_SHELL:=$$(SHELL)
        SHELL = $$(warning Building $$@$$(if $$<, (from $$<))$(if $$?, ($$? newer)))$$(OLD_SHELL) -x
    endif
endef

define ParseConfAndSpec
    ifneq ($$(origin SPEC),undefined)
        # We have been given a SPEC, check that it works out properly
        ifeq ($$(wildcard $$(SPEC)),)
            $$(info Cannot locate spec.gmk, given by SPEC=$$(SPEC))
            $$(eval $$(call fatal-error))
        endif
        ifneq ($$(origin CONF),undefined)
            # We also have a CONF argument. This is OK only if this is a repeated call by ourselves,
            # but complain if this is the top-level make call.
            ifeq ($$(MAKELEVEL),0)
                $$(info Cannot use CONF=$$(CONF) and SPEC=$$(SPEC) at the same time. Choose one.)
                $$(eval $$(call fatal-error))
            endif
        endif
        # ... OK, we're satisfied, we'll use this SPEC later on
    else
        # Find all spec.gmk files in the build output directory
        output_dir=$$(root_dir)/build
        all_spec_files=$$(wildcard $$(output_dir)/*/spec.gmk)
        ifeq ($$(all_spec_files),)
            $$(info No configurations found for $$(root_dir)! Please run configure to create a configuration.)
            $$(eval $$(call fatal-error))
        endif
        # Extract the configuration names from the path
        all_confs=$$(patsubst %/spec.gmk,%,$$(patsubst $$(output_dir)/%,%,$$(all_spec_files)))

        ifneq ($$(origin CONF),undefined)
            # User have given a CONF= argument.
            ifeq ($$(CONF),)
                # If given CONF=, match all configurations
                matching_confs=$$(strip $$(all_confs))
            else
                # Otherwise select those that contain the given CONF string
                matching_confs=$$(strip $$(foreach var,$$(all_confs),$$(if $$(findstring $$(CONF),$$(var)),$$(var))))
            endif
            ifeq ($$(matching_confs),)
                $$(info No configurations found matching CONF=$$(CONF))
                $$(info Available configurations:)
                $$(foreach var,$$(all_confs),$$(info * $$(var)))
                $$(eval $$(call fatal-error))
            else
                ifeq ($$(words $$(matching_confs)),1)
                    $$(info Building '$$(matching_confs)' (matching CONF=$$(CONF)))
                else
                    $$(info Building the following configurations (matching CONF=$$(CONF)):)
                    $$(foreach var,$$(matching_confs),$$(info * $$(var)))
                endif
            endif

            # Create a SPEC definition. This will contain the path to one or more spec.gmk files.
            SPEC=$$(addsuffix /spec.gmk,$$(addprefix $$(output_dir)/,$$(matching_confs)))
        else
            # No CONF or SPEC given, check the available configurations
            ifneq ($$(words $$(all_spec_files)),1)
                $$(info No CONF or SPEC given, but more than one spec.gmk found in $$(output_dir).)
                $$(info Available configurations:)
                $$(foreach var,$$(all_confs),$$(info * $$(var)))
                $$(info Please retry building with CONF=<config> or SPEC=<specfile>)
                $$(eval $$(call fatal-error))
            endif

            # We found exactly one configuration, use it
            SPEC=$$(strip $$(all_spec_files))
        endif
    endif
endef

define CheckEnvironment
    # Find all environment or command line variables that begin with ALT.
    $(if $(list_alt_overrides),
        @$(PRINTF) "\nWARNING: You have the following ALT_ variables set:\n"
    @$(PRINTF) "$(foreach var,$(list_alt_overrides),$(var)=$$$(var))\n"
    @$(PRINTF) "ALT_ variables are deprecated and will be ignored. Please clean your environment.\n\n"
    )
endef

define PrintStartMessage
    $(if $(VERBOSE),,@$(ECHO) Running make as $(MAKE) $(MFLAGS) $(MAKE_ARGS))
    $(call CheckEnvironment)
    @$(ECHO) "Building OpenJDK for target $(if $(MAKECMDGOALS),'$(MAKECMDGOALS)','all') in configuration '$(CONF_NAME)'"
endef

define PrintEndMessage
    @$(ECHO) "Finished building OpenJDK for target '$@'"
    $(call CheckEnvironment)
endef

endif # _MAKEHELPERS_GMK