# FIND_PACKAGE_HANDLE_STANDARD_ARGS(<name> ... )

#

# This function is intended to be used in FindXXX.cmake modules files.

# It handles the REQUIRED, QUIET and version-related arguments to FIND_PACKAGE().

# It also sets the <UPPERCASED_NAME>_FOUND variable.

# The package is considered found if all variables <var1>... listed contain

# valid results, e.g. valid filepaths.

#

# There are two modes of this function. The first argument in both modes is

# the name of the Find-module where it is called (in original casing).

#

# The first simple mode looks like this:

#    FIND_PACKAGE_HANDLE_STANDARD_ARGS(<name> (DEFAULT_MSG|"Custom failure message") <var1>...<varN> )

# If the variables <var1> to <varN> are all valid, then <UPPERCASED_NAME>_FOUND

# will be set to TRUE.

# If DEFAULT_MSG is given as second argument, then the function will generate

# itself useful success and error messages. You can also supply a custom error message

# for the failure case. This is not recommended.

#

# The second mode is more powerful and also supports version checking:

#    FIND_PACKAGE_HANDLE_STANDARD_ARGS(NAME [REQUIRED_VARS <var1>...<varN>]

#                                           [VERSION_VAR   <versionvar>]

#                                           [HANDLE_COMPONENTS]

#                                           [CONFIG_MODE]

#                                           [FAIL_MESSAGE "Custom failure message"] )

#

# As above, if <var1> through <varN> are all valid, <UPPERCASED_NAME>_FOUND

# will be set to TRUE.

# After REQUIRED_VARS the variables which are required for this package are listed.

# Following VERSION_VAR the name of the variable can be specified which holds

# the version of the package which has been found. If this is done, this version

# will be checked against the (potentially) specified required version used

# in the find_package() call. The EXACT keyword is also handled. The default

# messages include information about the required version and the version

# which has been actually found, both if the version is ok or not.

# If the package supports components, use the HANDLE_COMPONENTS option to enable

# handling them. In this case, find_package_handle_standard_args() will report

# which components have been found and which are missing, and the <NAME>_FOUND

# variable will be set to FALSE if any of the required components (i.e. not the

# ones listed after OPTIONAL_COMPONENTS) are missing.

# Use the option CONFIG_MODE if your FindXXX.cmake module is a wrapper for

# a find_package(... NO_MODULE) call.  In this case VERSION_VAR will be set

# to <NAME>_VERSION and the macro will automatically check whether the

# Config module was found.

# Via FAIL_MESSAGE a custom failure message can be specified, if this is not

# used, the default message will be displayed.

#

# Example for mode 1:

#

#    FIND_PACKAGE_HANDLE_STANDARD_ARGS(LibXml2  DEFAULT_MSG  LIBXML2_LIBRARY LIBXML2_INCLUDE_DIR)

#

# LibXml2 is considered to be found, if both LIBXML2_LIBRARY and

# LIBXML2_INCLUDE_DIR are valid. Then also LIBXML2_FOUND is set to TRUE.

# If it is not found and REQUIRED was used, it fails with FATAL_ERROR,

# independent whether QUIET was used or not.

# If it is found, success will be reported, including the content of <var1>.

# On repeated Cmake runs, the same message won't be printed again.

#

# Example for mode 2:

#

#    FIND_PACKAGE_HANDLE_STANDARD_ARGS(BISON  REQUIRED_VARS BISON_EXECUTABLE

#                                             VERSION_VAR BISON_VERSION)

# In this case, BISON is considered to be found if the variable(s) listed

# after REQUIRED_VAR are all valid, i.e. BISON_EXECUTABLE in this case.

# Also the version of BISON will be checked by using the version contained

# in BISON_VERSION.

# Since no FAIL_MESSAGE is given, the default messages will be printed.

#

# Another example for mode 2:

#

#    FIND_PACKAGE(Automoc4 QUIET NO_MODULE HINTS /opt/automoc4)

#    FIND_PACKAGE_HANDLE_STANDARD_ARGS(Automoc4  CONFIG_MODE)

# In this case, FindAutmoc4.cmake wraps a call to FIND_PACKAGE(Automoc4 NO_MODULE)

# and adds an additional search directory for automoc4.

# The following FIND_PACKAGE_HANDLE_STANDARD_ARGS() call produces a proper

# success/error message.

#=============================================================================

# Copyright 2007-2009 Kitware, Inc.

#

# Distributed under the OSI-approved BSD License (the "License");

# see accompanying file Copyright.txt for details.

#

# This software is distributed WITHOUT ANY WARRANTY; without even the

# implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

# See the License for more information.

#=============================================================================

# (To distribute this file outside of CMake, substitute the full

#  License text for the above reference.)

INCLUDE(FindPackageMessage)

INCLUDE(CMakeParseArguments)

# internal helper macro

MACRO(_FPHSA_FAILURE_MESSAGE _msg)

  IF (${_NAME}_FIND_REQUIRED)

    MESSAGE(FATAL_ERROR "${_msg}")

  ELSE (${_NAME}_FIND_REQUIRED)

    IF (NOT ${_NAME}_FIND_QUIETLY)

      MESSAGE(STATUS "${_msg}")

    ENDIF (NOT ${_NAME}_FIND_QUIETLY)

  ENDIF (${_NAME}_FIND_REQUIRED)

ENDMACRO(_FPHSA_FAILURE_MESSAGE _msg)

# internal helper macro to generate the failure message when used in CONFIG_MODE:

MACRO(_FPHSA_HANDLE_FAILURE_CONFIG_MODE)

  # <name>_CONFIG is set, but FOUND is false, this means that some other of the REQUIRED_VARS was not found:

  IF(${_NAME}_CONFIG)

    _FPHSA_FAILURE_MESSAGE("${FPHSA_FAIL_MESSAGE}: missing: ${MISSING_VARS} (found ${${_NAME}_CONFIG} ${VERSION_MSG})")

  ELSE(${_NAME}_CONFIG)

    # If _CONSIDERED_CONFIGS is set, the config-file has been found, but no suitable version.

    # List them all in the error message:

    IF(${_NAME}_CONSIDERED_CONFIGS)

      SET(configsText "")

      LIST(LENGTH ${_NAME}_CONSIDERED_CONFIGS configsCount)

      MATH(EXPR configsCount "${configsCount} - 1")

      FOREACH(currentConfigIndex RANGE ${configsCount})

        LIST(GET ${_NAME}_CONSIDERED_CONFIGS ${currentConfigIndex} filename)

        LIST(GET ${_NAME}_CONSIDERED_VERSIONS ${currentConfigIndex} version)

        SET(configsText "${configsText}    ${filename} (version ${version})\n")

      ENDFOREACH(currentConfigIndex)

      _FPHSA_FAILURE_MESSAGE("${FPHSA_FAIL_MESSAGE} ${VERSION_MSG}, checked the following files:\n${configsText}")

    ELSE(${_NAME}_CONSIDERED_CONFIGS)

      # Simple case: No Config-file was found at all:

      _FPHSA_FAILURE_MESSAGE("${FPHSA_FAIL_MESSAGE}: found neither ${_NAME}Config.cmake nor ${_NAME_LOWER}-config.cmake ${VERSION_MSG}")

    ENDIF(${_NAME}_CONSIDERED_CONFIGS)

  ENDIF(${_NAME}_CONFIG)

ENDMACRO(_FPHSA_HANDLE_FAILURE_CONFIG_MODE)

FUNCTION(FIND_PACKAGE_HANDLE_STANDARD_ARGS _NAME _FIRST_ARG)

# set up the arguments for CMAKE_PARSE_ARGUMENTS and check whether we are in

# new extended or in the "old" mode:

  SET(options CONFIG_MODE HANDLE_COMPONENTS)

  SET(oneValueArgs FAIL_MESSAGE VERSION_VAR)

  SET(multiValueArgs REQUIRED_VARS)

  SET(_KEYWORDS_FOR_EXTENDED_MODE  ${options} ${oneValueArgs} ${multiValueArgs} )

  LIST(FIND _KEYWORDS_FOR_EXTENDED_MODE "${_FIRST_ARG}" INDEX)

  IF(${INDEX} EQUAL -1)

    SET(FPHSA_FAIL_MESSAGE ${_FIRST_ARG})

    SET(FPHSA_REQUIRED_VARS ${ARGN})

    SET(FPHSA_VERSION_VAR)

  ELSE(${INDEX} EQUAL -1)

    CMAKE_PARSE_ARGUMENTS(FPHSA "${options}" "${oneValueArgs}" "${multiValueArgs}"  ${_FIRST_ARG} ${ARGN})

    IF(FPHSA_UNPARSED_ARGUMENTS)

      MESSAGE(FATAL_ERROR "Unknown keywords given to FIND_PACKAGE_HANDLE_STANDARD_ARGS(): \"${FPHSA_UNPARSED_ARGUMENTS}\"")

    ENDIF(FPHSA_UNPARSED_ARGUMENTS)

    IF(NOT FPHSA_FAIL_MESSAGE)

      SET(FPHSA_FAIL_MESSAGE  "DEFAULT_MSG")

    ENDIF(NOT FPHSA_FAIL_MESSAGE)

  ENDIF(${INDEX} EQUAL -1)

# now that we collected all arguments, process them

  IF("${FPHSA_FAIL_MESSAGE}" STREQUAL "DEFAULT_MSG")

    SET(FPHSA_FAIL_MESSAGE "Could NOT find ${_NAME}")

  ENDIF("${FPHSA_FAIL_MESSAGE}" STREQUAL "DEFAULT_MSG")

  # In config-mode, we rely on the variable <package>_CONFIG, which is set by find_package()

  # when it successfully found the config-file, including version checking:

  IF(FPHSA_CONFIG_MODE)

    LIST(INSERT FPHSA_REQUIRED_VARS 0 ${_NAME}_CONFIG)

    LIST(REMOVE_DUPLICATES FPHSA_REQUIRED_VARS)

    SET(FPHSA_VERSION_VAR ${_NAME}_VERSION)

  ENDIF(FPHSA_CONFIG_MODE)

  IF(NOT FPHSA_REQUIRED_VARS)

    MESSAGE(FATAL_ERROR "No REQUIRED_VARS specified for FIND_PACKAGE_HANDLE_STANDARD_ARGS()")

  ENDIF(NOT FPHSA_REQUIRED_VARS)

  LIST(GET FPHSA_REQUIRED_VARS 0 _FIRST_REQUIRED_VAR)

  STRING(TOUPPER ${_NAME} _NAME_UPPER)

  STRING(TOLOWER ${_NAME} _NAME_LOWER)

  # collect all variables which were not found, so they can be printed, so the

  # user knows better what went wrong (#6375)

  SET(MISSING_VARS "")

  SET(DETAILS "")

  SET(${_NAME_UPPER}_FOUND TRUE)

  # check if all passed variables are valid

  FOREACH(_CURRENT_VAR ${FPHSA_REQUIRED_VARS})

    IF(NOT ${_CURRENT_VAR})

      SET(${_NAME_UPPER}_FOUND FALSE)

      SET(MISSING_VARS "${MISSING_VARS} ${_CURRENT_VAR}")

    ELSE(NOT ${_CURRENT_VAR})

      SET(DETAILS "${DETAILS}[${${_CURRENT_VAR}}]")

    ENDIF(NOT ${_CURRENT_VAR})

  ENDFOREACH(_CURRENT_VAR)

  # component handling

  UNSET(FOUND_COMPONENTS_MSG)

  UNSET(MISSING_COMPONENTS_MSG)

  IF(FPHSA_HANDLE_COMPONENTS)

    FOREACH(comp ${${_NAME}_FIND_COMPONENTS})

      IF(${_NAME}_${comp}_FOUND)

        IF(NOT DEFINED FOUND_COMPONENTS_MSG)

          SET(FOUND_COMPONENTS_MSG "found components: ")

        ENDIF()

        SET(FOUND_COMPONENTS_MSG "${FOUND_COMPONENTS_MSG} ${comp}")

      ELSE()

        IF(NOT DEFINED MISSING_COMPONENTS_MSG)

          SET(MISSING_COMPONENTS_MSG "missing components: ")

        ENDIF()

        SET(MISSING_COMPONENTS_MSG "${MISSING_COMPONENTS_MSG} ${comp}")

        IF(${_NAME}_FIND_REQUIRED_${comp})

          SET(${_NAME_UPPER}_FOUND FALSE)

          SET(MISSING_VARS "${MISSING_VARS} ${comp}")

        ENDIF()

      ENDIF()

    ENDFOREACH(comp)

    SET(COMPONENT_MSG "${FOUND_COMPONENTS_MSG} ${MISSING_COMPONENTS_MSG}")

    SET(DETAILS "${DETAILS}[c${COMPONENT_MSG}]")

  ENDIF(FPHSA_HANDLE_COMPONENTS)

  # version handling:

  SET(VERSION_MSG "")

  SET(VERSION_OK TRUE)

  SET(VERSION ${${FPHSA_VERSION_VAR}} )

  IF (${_NAME}_FIND_VERSION)

    IF(VERSION)

      IF(${_NAME}_FIND_VERSION_EXACT)       # exact version required

        IF (NOT "${${_NAME}_FIND_VERSION}" VERSION_EQUAL "${VERSION}")

          SET(VERSION_MSG "Found unsuitable version \"${VERSION}\", but required is exact version \"${${_NAME}_FIND_VERSION}\"")

          SET(VERSION_OK FALSE)

        ELSE (NOT "${${_NAME}_FIND_VERSION}" VERSION_EQUAL "${VERSION}")

          SET(VERSION_MSG "(found suitable exact version \"${VERSION}\")")

        ENDIF (NOT "${${_NAME}_FIND_VERSION}" VERSION_EQUAL "${VERSION}")

      ELSE(${_NAME}_FIND_VERSION_EXACT)     # minimum version specified:

        IF ("${${_NAME}_FIND_VERSION}" VERSION_GREATER "${VERSION}")

          SET(VERSION_MSG "Found unsuitable version \"${VERSION}\", but required is at least \"${${_NAME}_FIND_VERSION}\"")

          SET(VERSION_OK FALSE)

        ELSE ("${${_NAME}_FIND_VERSION}" VERSION_GREATER "${VERSION}")

          SET(VERSION_MSG "(found suitable version \"${VERSION}\", required is \"${${_NAME}_FIND_VERSION}\")")

        ENDIF ("${${_NAME}_FIND_VERSION}" VERSION_GREATER "${VERSION}")

      ENDIF(${_NAME}_FIND_VERSION_EXACT)

    ELSE(VERSION)

      # if the package was not found, but a version was given, add that to the output:

      IF(${_NAME}_FIND_VERSION_EXACT)

         SET(VERSION_MSG "(Required is exact version \"${${_NAME}_FIND_VERSION}\")")

      ELSE(${_NAME}_FIND_VERSION_EXACT)

         SET(VERSION_MSG "(Required is at least version \"${${_NAME}_FIND_VERSION}\")")

      ENDIF(${_NAME}_FIND_VERSION_EXACT)

    ENDIF(VERSION)

  ELSE (${_NAME}_FIND_VERSION)

    IF(VERSION)

      SET(VERSION_MSG "(found version \"${VERSION}\")")

    ENDIF(VERSION)

  ENDIF (${_NAME}_FIND_VERSION)

  IF(VERSION_OK)

    SET(DETAILS "${DETAILS}[v${VERSION}(${${_NAME}_FIND_VERSION})]")

  ELSE(VERSION_OK)

    SET(${_NAME_UPPER}_FOUND FALSE)

  ENDIF(VERSION_OK)

  # print the result:

  IF (${_NAME_UPPER}_FOUND)

    FIND_PACKAGE_MESSAGE(${_NAME} "Found ${_NAME}: ${${_FIRST_REQUIRED_VAR}} ${VERSION_MSG} ${COMPONENT_MSG}" "${DETAILS}")

  ELSE (${_NAME_UPPER}_FOUND)

    IF(FPHSA_CONFIG_MODE)

      _FPHSA_HANDLE_FAILURE_CONFIG_MODE()

    ELSE(FPHSA_CONFIG_MODE)

      IF(NOT VERSION_OK)

        _FPHSA_FAILURE_MESSAGE("${FPHSA_FAIL_MESSAGE}: ${VERSION_MSG} (found ${${_FIRST_REQUIRED_VAR}})")

      ELSE(NOT VERSION_OK)

        _FPHSA_FAILURE_MESSAGE("${FPHSA_FAIL_MESSAGE} (missing: ${MISSING_VARS}) ${VERSION_MSG}")

      ENDIF(NOT VERSION_OK)

    ENDIF(FPHSA_CONFIG_MODE)

  ENDIF (${_NAME_UPPER}_FOUND)

  SET(${_NAME_UPPER}_FOUND ${${_NAME_UPPER}_FOUND} PARENT_SCOPE)

ENDFUNCTION(FIND_PACKAGE_HANDLE_STANDARD_ARGS _FIRST_ARG)