#
# Copyright (c) 2019, 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.
#

ifeq (,$(_MAKEBASE_GMK))
  $(error You must include MakeBase.gmk prior to including Execute.gmk)
endif

################################################################################
#
# Code for handling the SetupExecute macro.
#
################################################################################


################################################################################
# Setup make rules for executing an arbitrary command.
#
# Parameter 1 is the name of the rule. This name is used as variable prefix,
# and the targets generated are listed in a variable by that name.
#
# You need to specify a COMMAND, the actual command line to execute. You are
# strongly recommended to provide a INFO with the text to display for LOG=info
# on what operation is performed. You can use DEPS to provide additional
# dependencies for your command to run. You can optionally include a PRE_COMMAND
# and a POST_COMMAND, intended for simple pre- and post-processing. The latter
# might be e.g. a mv from a temporary file to the final destination, the former
# e.g. a simple sed replacement on the input file. If the operations are
# unrelated to the main COMMAND, this is not a suitable solution.
#
# If your command outputs a variety of files, or if it's really a single file
# but you don't really care about the output from the perspective, you can just
# supply an OUTPUT_DIR. You are supposed to make sure the command creates files
# in this directory (which will be created for you if it does not exist), but
# this can't be enforced by SetupExecute. Additional support files (like logs
# and markers) are created in this directory. If you want support files in a
# separate directory (e.g. if you're targeting an OUTPUT_DIR in the image
# directly), you can specify a SUPPORT_DIR. If your command outputs only a
# single file, you can get rid of the marker files (but not the log files) by
# specifying OUTPUT_FILE. Note that if you specify an OUTPUT_FILE, support log
# files will be placed in the same directory as the OUTPUT_FILE. If you do not
# want that, use SUPPORT_DIR as well.
#
# After the call to SetupExecute, $1 will contain references to all generated
# files (that make knows about), and $1_TARGET will contain a reference to the
# final target (that is OUTPUT_FILE if it exists, or the $1_exec.marker file
# otherwise).
#
# All the above keep functioning as expected even if PRE_COMMAND and
# POST_COMMAND are given. One special case worth noting is that if OUTPUT_FILE
# and POST_COMMAND is both given, the actual OUTPUT_FILE is considered to be a
# result of running the POST_COMMAND.
#
# Remaining parameters are named arguments. These include:
#   COMMAND     : The command to execute
#   PRE_COMMAND : A helper command to execute before COMMAND
#   POST_COMMAND: A helper command to execute after COMMAND
#   OUTPUT_DIR  : The directory that will contain the result from the command
#   OUTPUT_FILE : Use this if the command results in a single output file
#   SUPPORT_DIR : Where to store generated support files
#   INFO        : Message to display at LOG=info level when running command (optional)
#   WARN        : Message to display at LOG=warn level when running command (optional)
#   DEPS        : Dependencies for the execution to take place
#

# Setup make rules for copying files, with an option to do more complex
SetupExecute = $(NamedParamsMacroTemplate)
define SetupExecuteBody
  ifeq ($$($1_COMMAND), )
    $$(error COMMAND is missing in SetupExecute $1)
  endif

  ifneq ($$($1_OUTPUT_FILE), )
    ifneq ($$($1_OUTPUT_DIR), )
      $$(error Cannot specify both OUTPUT_DIR and OUTPUT_FILE in SetupExecute $1)
    endif
    # We need to know output dir since we will make sure it is created.
    $1_OUTPUT_DIR := $$(patsubst %/,%, $$(dir $$($1_OUTPUT_FILE)))
    ifeq ($$($1_SUPPORT_DIR), )
      # If support dir is not given, use base dir of output file.
      $1_SUPPORT_DIR := $$($1_OUTPUT_DIR)
    endif
  else ifneq ($$($1_OUTPUT_DIR), )
    ifeq ($$($1_SUPPORT_DIR), )
      # If support dir is not given, use output dir.
      $1_SUPPORT_DIR := $$($1_OUTPUT_DIR)
    endif
  else
    $$(error OUTPUT_DIR or OUTPUT_FILE is required in SetupExecute $1)
  endif

  $1_BASE := $$($1_SUPPORT_DIR)/_$1
  $1_PRE_MARKER := $$($1_BASE)_pre.marker
  $1_EXEC_MARKER := $$($1_BASE)_exec.marker
  $1_POST_MARKER := $$($1_BASE)_post.marker

  ifeq ($$($1_OUTPUT_FILE), )
    # No specified output file, use markers everywhere
    $1_EXEC_RESULT := $$($1_EXEC_MARKER)
    ifeq ($$($1_POST_COMMAND), )
      $1_FINAL_RESULT := $$($1_EXEC_MARKER)
    else
      $1_FINAL_RESULT := $$($1_POST_MARKER)
    endif

  else
    # If we have a single output file, we don't need a separate marker

    ifeq ($$($1_POST_COMMAND), )
      $1_EXEC_RESULT := $$($1_OUTPUT_FILE)
      $1_FINAL_RESULT := $$($1_EXEC_RESULT)
    else
      $1_EXEC_RESULT := $$($1_EXEC_MARKER)
      $1_FINAL_RESULT := $$($1_OUTPUT_FILE)
    endif

  endif

  ifeq ($$($1_INFO)$$($1_WARN), )
    # If neither info nor warn is provided, add basic info text.
    $1_INFO := Running commands for $1
  endif

  ifneq ($$($1_PRE_COMMAND), )

    $$($1_PRE_MARKER): $$($1_DEPS)
        ifneq ($$($1_WARN), )
	  $$(call LogWarn, $$($1_WARN))
        endif
        ifneq ($$($1_INFO), )
	  $$(call LogInfo, $$($1_INFO))
        endif
	$$(call MakeDir, $$($1_SUPPORT_DIR) $$($1_OUTPUT_DIR))
	$$(call ExecuteWithLog, $$($1_BASE)_pre, \
	    $$($1_PRE_COMMAND))
	$$(TOUCH) $$@

    $$($1_EXEC_RESULT): $$($1_PRE_MARKER)
	$$(call ExecuteWithLog, $$($1_BASE)_exec, \
	    $$($1_COMMAND))
        ifeq ($$($1_EXEC_RESULT), $$($1_EXEC_MARKER))
	  $$(TOUCH) $$@
        endif

    $1 := $$($1_PRE_MARKER) $$($1_EXEC_RESULT)
  else
    $$($1_EXEC_RESULT): $$($1_DEPS)
        ifneq ($$($1_WARN), )
	  $$(call LogWarn, $$($1_WARN))
        endif
        ifneq ($$($1_INFO), )
	  $$(call LogInfo, $$($1_INFO))
        endif
	$$(call MakeDir, $$(call EncodeSpace, $$($1_SUPPORT_DIR)) $$(call EncodeSpace, $$($1_OUTPUT_DIR)))
	$$(call ExecuteWithLog, $$($1_BASE)_exec, \
	    $$($1_COMMAND))
        ifeq ($$($1_EXEC_RESULT), $$($1_EXEC_MARKER))
	  $$(TOUCH) $$@
        endif

    $1 := $$($1_EXEC_RESULT)
  endif

  ifneq ($$($1_POST_COMMAND), )

    $$($1_FINAL_RESULT): $$($1_EXEC_RESULT)
	$$(call ExecuteWithLog, $$($1_BASE)_post, \
	    $$($1_POST_COMMAND))
	$$(TOUCH) $$@

    $1 += $$($1_FINAL_RESULT)
  endif

  # Export all our generated targets in $1, and the final target in $1_TARGET.
  $1_TARGET := $$($1_FINAL_RESULT)

endef