#
# ITK
#

set(proj ITK)

set(${proj}_DEPENDENCIES "")

ExternalProject_Include_Dependencies(${proj}
  PROJECT_VAR proj
  DEPENDS_VAR ${proj}_DEPENDENCIES
  EP_ARGS_VAR ${proj}_EXTERNAL_PROJECT_ARGS
  USE_SYSTEM_VAR ${CMAKE_PROJECT_NAME}_USE_SYSTEM_${proj}
  )

# Let the user to chose whether to use libs installed in the system
option(${CMAKE_PROJECT_NAME}_USE_SYSTEM_${proj} "Use installed ${proj} library in the system" OFF)
mark_as_advanced(${CMAKE_PROJECT_NAME}_USE_SYSTEM_${proj})

if(${CMAKE_PROJECT_NAME}_USE_SYSTEM_${proj})
  unset(ITK_DIR CACHE)
  find_package(ITK REQUIRED NO_MODULE)
endif()

# Sanity checks
if(DEFINED ITK_DIR AND NOT EXISTS ${ITK_DIR})
  message(FATAL_ERROR "ITK_DIR variable is defined but corresponds to non-existing directory")
endif()

if(NOT DEFINED ITK_DIR AND NOT ${CMAKE_PROJECT_NAME}_USE_SYSTEM_${proj})

  if("${CMAKE_CXX_STANDARD}" STREQUAL "98")
    set(revision_tag "v4.13.3")
  else()
    set(revision_tag "v5.1.2")
  endif()
  if(${proj}_REVISION_TAG)
    set(revision_tag ${${proj}_REVISION_TAG})
  endif()
  ExternalProject_Message(${proj} "${proj}[revision_tag:${revision_tag}]")

  set(location_args )
  if(${proj}_URL)
    set(location_args URL ${${proj}_URL})
  elseif(${proj}_GIT_REPOSITORY)
    set(location_args GIT_REPOSITORY ${${proj}_GIT_REPOSITORY}
                      GIT_TAG ${revision_tag})
  else()
    set(location_args GIT_REPOSITORY "${EP_GIT_PROTOCOL}://github.com/InsightSoftwareConsortium/ITK"
                      GIT_TAG ${revision_tag})
  endif()

  ExternalProject_Add(${proj}
    ${${proj}_EXTERNAL_PROJECT_ARGS}
    SOURCE_DIR ${CMAKE_BINARY_DIR}/${proj}
    BINARY_DIR ${proj}-build
    PREFIX ${proj}${ep_suffix}
    ${location_args}
    INSTALL_COMMAND ""
    CMAKE_CACHE_ARGS
      ${ep_common_cache_args}
      -DBUILD_EXAMPLES:BOOL=OFF
      -DBUILD_SHARED_LIBS:BOOL=ON
      -DITK_LEGACY_REMOVE:BOOL=ON
    DEPENDS
      ${${proj}_DEPENDENCIES}
    )
  set(ITK_DIR ${CMAKE_BINARY_DIR}/${proj}-build)

  #-----------------------------------------------------------------------------
  # Launcher setting specific to build tree

  set(_lib_subdir lib)
  if(WIN32)
    set(_lib_subdir bin)
  endif()

  # library paths
  set(${proj}_LIBRARY_PATHS_LAUNCHER_BUILD ${ITK_DIR}/${_lib_subdir}/<CMAKE_CFG_INTDIR>)
  mark_as_superbuild(
    VARS ${proj}_LIBRARY_PATHS_LAUNCHER_BUILD
    LABELS "LIBRARY_PATHS_LAUNCHER_BUILD"
    )

  #-----------------------------------------------------------------------------
  # Launcher setting specific to install tree

  # NA

else()
  ExternalProject_Add_Empty(${proj} DEPENDS ${${proj}_DEPENDENCIES})
endif()

mark_as_superbuild(
  VARS ITK_DIR:PATH
  LABELS "FIND_PACKAGE"
  )