#.rst:
#
# .. cmake:command:: usFunctionGetResourceSource
#
# Get a source file name for handling resource dependencies
#
# .. code-block:: cmake
#
#    usFunctionGetResourceSource(TARGET target OUT <out_var> [LINK | APPEND])
#
# This CMake function retrieves the name of a generated file which has to be added
# to a bundles source file list to set-up resource file dependencies. This ensures
# that changed resource files will automatically be re-added to the bundle.
#
# .. code-block:: cmake
#    :caption: Example
#
#    set(bundle_srcs mylib.cpp)
#    usFunctionGetResourceSource(TARGET mylib
#                                OUT bundle_srcs
#                               )
#    add_library(mylib ${bundle_srcs})
#
# **One-value keywords**
#    * ``TARGET`` (required): The name of the target to which the resource files are added.
#    * ``OUT`` (required): A list variable to which the file name will be appended.
#
# **Options**
#    * ``LINK`` (optional): Generate a suitable source file for *LINK* mode.
#    * ``APPEND`` (optional): Generate a suitable source file for *APPEND* mode.
#
# .. seealso::
#
#    | :cmake:command:`usFunctionAddResources`
#    | :cmake:command:`usFunctionEmbedResources`
#
function(usFunctionGetResourceSource)
  cmake_parse_arguments(_res "LINK;APPEND" "TARGET;OUT" "" "" ${ARGN})
  if(NOT _res_TARGET)
    message(SEND_ERROR "TARGET must not be empty")
  endif()
  if(NOT _res_OUT)
    message(SEND_ERROR "OUT argument must not be empty")
  endif()
  if(_res_LINK AND _res_APPEND)
    message(SEND_ERROR "Both LINK and APPEND options given.")
  endif()

  set(_out "${CMAKE_CURRENT_BINARY_DIR}/${_res_TARGET}/cppmicroservices_resources")
  if(_res_LINK)
    set(_out "${_out}${US_RESOURCE_SOURCE_SUFFIX_LINK}")
  elseif(_res_APPEND)
    set(_out "${_out}${US_RESOURCE_SOURCE_SUFFIX_APPEND}")
  else()
    set(_out "${_out}${US_RESOURCE_SOURCE_SUFFIX}")
  endif()

  set(${_res_OUT} ${${_res_OUT}} ${_out} PARENT_SCOPE)
endfunction()