FIND_PACKAGE( Doxygen QUIET)

IF( DOXYGEN_FOUND )
  IF( DOXYGEN_DOT_FOUND )

    # Automatically generate documentation at build time
    SET(all_arg)
    IF (DOCUMENTATION_TARGET_IN_ALL)
      SET(all_arg "ALL")
    ENDIF()

    #
    # User documentation
    #
    SET( CTK_USER_DOCUMENTATION "NO" )
    SET( CTK_ADDITIONAL_EXCLUDE_PATTERN "*_p.h\  *Private.*" )
    SET( CTK_DOCUMENTATION_HTML_TARZ TRUE)

    CONFIGURE_FILE( Doxyfile.txt.in
      ${CMAKE_CURRENT_BINARY_DIR}/UserDoxyfile.txt
      )

    CONFIGURE_FILE(
      ${CMAKE_CURRENT_SOURCE_DIR}/generate_doc.cmake.in
      ${CMAKE_CURRENT_BINARY_DIR}/generate_userdoc.cmake
      @ONLY
      )

    SET(userdoc_output "${CMAKE_CURRENT_BINARY_DIR}/doc/html/index.html")
    
    # Run doxygen as a custom command driven by a custom target.
    ADD_CUSTOM_COMMAND(
      OUTPUT ${userdoc_output}
      COMMAND ${CMAKE_COMMAND} -P "${CMAKE_CURRENT_BINARY_DIR}/generate_userdoc.cmake"
      DEPENDS "${CMAKE_CURRENT_BINARY_DIR}/generate_userdoc.cmake"
              "${CMAKE_CURRENT_BINARY_DIR}/UserDoxyfile.txt"
      )

    ADD_CUSTOM_TARGET(doc ${all_arg} DEPENDS ${userdoc_output})
            
#     ADD_CUSTOM_TARGET( doc ${all_arg}
#       ${DOXYGEN_EXECUTABLE} ${CTK_BINARY_DIR}/Documentation/UserDoxyfile.txt 
#       DEPENDS ${CTK_BINARY_DIR}/Documentation/UserDoxyfile.txt
#       ) 

    #
    # Dev documentation
    #
    SET( CTK_USER_DOCUMENTATION "YES" )
    SET( CTK_ADDITIONAL_EXCLUDE_PATTERN "" )

    CONFIGURE_FILE( Doxyfile.txt.in
      ${CMAKE_CURRENT_BINARY_DIR}/DevDoxyfile.txt
      )

    ADD_CUSTOM_TARGET( doc-dev
      ${DOXYGEN_EXECUTABLE} ${CMAKE_CURRENT_BINARY_DIR}/DevDoxyfile.txt
      DEPENDS ${CMAKE_CURRENT_BINARY_DIR}/DevDoxyfile.txt
      )
    
  ELSE( DOXYGEN_DOT_FOUND )
    MESSAGE( WARNING
      "Warning: Dot not found - Documentation will not be created"
      )
  ENDIF( DOXYGEN_DOT_FOUND )
ENDIF( DOXYGEN_FOUND )