project(Documentation NONE)

option(BUILD_DOC "Build the doxygen documentation" OFF)
if(NOT BUILD_DOC)
  return()
endif()

# Visual Studio users might appreciate this
# set_property(GLOBAL PROPERTY USE_FOLDERS ON)

macro(subdirlist result curdir)
  file(GLOB children RELATIVE ${curdir} ${curdir}/*)
  set(dirlist "")
  foreach(child ${children})
    if(IS_DIRECTORY ${curdir}/${child})
      set(dirlist ${dirlist} ${child})
    endif()
  endforeach()
  set(${result} ${dirlist})
endmacro()

function(configure_doxygen_package CGAL_PACKAGE_NAME)
  if(CGAL_BRANCH_BUILD)
    set(CGAL_PACKAGE_DOC_DIR ${CMAKE_SOURCE_DIR}/${CGAL_PACKAGE_NAME}/doc/${CGAL_PACKAGE_NAME})
  else()
    set(CGAL_PACKAGE_DOC_DIR ${CMAKE_SOURCE_DIR}/doc/${CGAL_PACKAGE_NAME})
  endif()
  if(NOT IS_DIRECTORY ${CGAL_PACKAGE_DOC_DIR})
    message(STATUS "${CGAL_PACKAGE_NAME} reported but has no doc dir: ${CGAL_PACKAGE_DOC_DIR}")
    return()
  else()
    message(STATUS "Configuring documentation of ${CGAL_PACKAGE_NAME}")
  endif()

  set(CGAL_PACKAGE_DIR ${CMAKE_SOURCE_DIR}/${CGAL_PACKAGE_NAME})
  if(EXISTS ${CGAL_PACKAGE_DOC_DIR}/Doxyfile.in)
    set(CGAL_DOC_PACKAGE_DEFAULTS ${CGAL_DOC_DXY_DIR}/${CGAL_PACKAGE_NAME}_defaults.dxy)
    file(REMOVE ${CGAL_DOC_PACKAGE_DEFAULTS})
    file(APPEND ${CGAL_DOC_PACKAGE_DEFAULTS} "@INCLUDE = ${CGAL_DOC_DOXY_DEFAULT}\n")
    file(APPEND ${CGAL_DOC_PACKAGE_DEFAULTS} "OUTPUT_DIRECTORY = ${CGAL_DOC_OUTPUT_DIR}/${CGAL_PACKAGE_NAME}\n")
    file(APPEND ${CGAL_DOC_PACKAGE_DEFAULTS} "HTML_OUTPUT = .\n")

    if(CGAL_DOC_CREATE_LOGS)
      file(APPEND ${CGAL_DOC_PACKAGE_DEFAULTS} "WARN_LOGFILE = ${CGAL_DOC_LOG_DIR}/${CGAL_PACKAGE_NAME}.log\n")
    endif()

    if (CGAL_DOC_RELEASE)
      file(APPEND ${CGAL_DOC_PACKAGE_DEFAULTS} "GENERATE_TODOLIST = NO\n")
      file(APPEND ${CGAL_DOC_PACKAGE_DEFAULTS} "GENERATE_BUGLIST = NO\n")
    endif()

    if(EXISTS "${CGAL_PACKAGE_DIR}/examples")
      file(APPEND ${CGAL_DOC_PACKAGE_DEFAULTS} "EXAMPLE_PATH = ${CGAL_PACKAGE_DIR}/examples\n")
    endif()
    file(APPEND ${CGAL_DOC_PACKAGE_DEFAULTS} "GENERATE_TAGFILE = ${CGAL_DOC_TAG_GEN_DIR}/${CGAL_PACKAGE_NAME}.tag\n")
    file(APPEND ${CGAL_DOC_PACKAGE_DEFAULTS} "STRIP_FROM_PATH = ${CGAL_PACKAGE_DOC_DIR}/\n")
    file(APPEND ${CGAL_DOC_PACKAGE_DEFAULTS} "STRIP_FROM_PATH += ${CGAL_PACKAGE_DIR}/include/\n")
    file(APPEND ${CGAL_DOC_PACKAGE_DEFAULTS} "STRIP_FROM_INC_PATH = ${CGAL_PACKAGE_DOC_DIR}/\n")
    file(APPEND ${CGAL_DOC_PACKAGE_DEFAULTS} "STRIP_FROM_INC_PATH += ${CGAL_PACKAGE_DIR}/include/\n")
    file(APPEND ${CGAL_DOC_PACKAGE_DEFAULTS} "ALIASES += \"cgalPkgDescriptionBegin{2}=\\details \"\n")
    file(APPEND ${CGAL_DOC_PACKAGE_DEFAULTS} "ALIASES += \"cgalPkgManuals{2}=<BR>\"\n")
    file(APPEND ${CGAL_DOC_PACKAGE_DEFAULTS} "INPUT = ${CGAL_PACKAGE_DOC_DIR}\n")

    # IMAGE_PATH is set by default. For Documentation, we generate the extra path using packages.txt
    set(IMAGE_PATH_VALUES "IMAGE_PATH = ${CGAL_PACKAGE_DOC_DIR}/fig")
    set(DEPENDENCIES "")
    # figure out the dependencies, using the file `dependencies` or `packages.txt` for Documentation
    if (${CGAL_PACKAGE_NAME} STREQUAL "Documentation")
      set(PackageFile ${CGAL_PACKAGE_DOC_DIR}/packages.txt)
      file(READ ${PackageFile} Entries)
      string(REPLACE "\n" ";" EntriesAsList ${Entries})
      foreach(Line ${EntriesAsList})
        if("${Line}" MATCHES "^\\\\package_listing{.+}$")
          string(REGEX REPLACE "^\\\\package_listing{(.+)}$" "\\1" PKG "${Line}")
          list(APPEND DEPENDENCIES ${PKG})
          # update IMAGE_PATH
          SET(IMG_DIR "${CMAKE_SOURCE_DIR}/${PKG}/doc/${PKG}/fig")
          if(EXISTS ${IMG_DIR})
            set(IMAGE_PATH_VALUES "${IMAGE_PATH_VALUES} \\\n             ${IMG_DIR}")
          endif()
        endif()
      endforeach()
      set(IMAGE_PATH_VALUES ${IMAGE_PATH_VALUES} PARENT_SCOPE)
      set(DOCUMENTATION_DEPENDENCIES ${DEPENDENCIES} PARENT_SCOPE)
    else()
      if(EXISTS ${CGAL_PACKAGE_DOC_DIR}/dependencies)
        file(STRINGS ${CGAL_PACKAGE_DOC_DIR}/dependencies DEPENDENCIES)
      endif()
    endif()

    foreach(depend ${DEPENDENCIES})
      file(APPEND ${CGAL_DOC_PACKAGE_DEFAULTS} 
        "TAGFILES += ${CGAL_DOC_TAG_DIR}/${depend}.tag=../${depend}\n")
    endforeach()
    
    #now write IMAGE_PATH
    file(APPEND ${CGAL_DOC_PACKAGE_DEFAULTS} "${IMAGE_PATH_VALUES}\n")

    configure_file(${CGAL_PACKAGE_DOC_DIR}/Doxyfile.in ${CGAL_DOC_DXY_DIR}/${CGAL_PACKAGE_NAME}.dxy)
    
    # TODO we also want to run html_post_process per package as a custom_command with POST_BUILD
    # target that build the doc and put the tag file in the generation directory CGAL_DOC_TAG_GEN_DIR
    add_custom_target(${CGAL_PACKAGE_NAME}_internal_doxygen_run
      ${DOXYGEN_EXECUTABLE} ${CGAL_DOC_DXY_DIR}/${CGAL_PACKAGE_NAME}.dxy)

    set_target_properties(${CGAL_PACKAGE_NAME}_internal_doxygen_run PROPERTIES FOLDER Documentation/Packages)

    #target moving the tag file into the read directory CGAL_DOC_TAG_DIR
    if ( "${CGAL_PACKAGE_NAME}" STREQUAL "Documentation" )
      set(CGAL_PACKAGE_TAGFILE "Manual.tag")
    else()
      set(CGAL_PACKAGE_TAGFILE "${CGAL_PACKAGE_NAME}.tag")
    endif()
    add_custom_target(${CGAL_PACKAGE_NAME}_copy_doc_tags
                      ${CMAKE_COMMAND} -E copy
                        "${CGAL_DOC_TAG_GEN_DIR}/${CGAL_PACKAGE_TAGFILE}"
                        "${CGAL_DOC_TAG_DIR}/${CGAL_PACKAGE_TAGFILE}"
    )

    #add the doc target doing both the doc generation and then the tag file copy
    add_custom_target(${CGAL_PACKAGE_NAME}_doc
      ${DOXYGEN_EXECUTABLE} ${CGAL_DOC_DXY_DIR}/${CGAL_PACKAGE_NAME}.dxy
      COMMAND
      ${CMAKE_COMMAND} -E copy
                        "${CGAL_DOC_TAG_GEN_DIR}/${CGAL_PACKAGE_TAGFILE}"
                        "${CGAL_DOC_TAG_DIR}/${CGAL_PACKAGE_TAGFILE}"
    )

    #     ${depend}_doc)
    # don't do this for now
    # foreach(depend ${DEPENDENCIES})
    #   add_dependencies(${CGAL_PACKAGE_NAME}_doc
    #     ${depend}_doc)
    # endforeach()
    
  endif()
endfunction()

find_package(Doxygen)
find_package(PythonInterp 2.6.7)

if(DOXYGEN_FOUND)
  # set up the directories and variables
  set(CGAL_DOC_MATHJAX_LOCATION "https://cdn.mathjax.org/mathjax/latest"
      CACHE STRING "The location of MathJax to be used for the documentation.")

  set(CGAL_DOC_OUTPUT_DIR "${CMAKE_BINARY_DIR}/doc_output")
  file(MAKE_DIRECTORY "${CGAL_DOC_OUTPUT_DIR}")
  
  option(CGAL_DOC_CREATE_LOGS "Write log files or print warnings and errors to cerr when building the doc." OFF)

  if(CGAL_DOC_CREATE_LOGS)
    set(CGAL_DOC_LOG_DIR "${CMAKE_BINARY_DIR}/doc_log")
    file(MAKE_DIRECTORY "${CGAL_DOC_LOG_DIR}")
  endif()

  #we use two directories for the generation/reading of tag files to prevent issues
  #if the targets are built in parallel
  set(CGAL_DOC_TAG_GEN_DIR "${CMAKE_BINARY_DIR}/doc_gen_tags")
  file(MAKE_DIRECTORY "${CGAL_DOC_TAG_GEN_DIR}")
  set(CGAL_DOC_TAG_DIR "${CMAKE_BINARY_DIR}/doc_tags")
  file(MAKE_DIRECTORY "${CGAL_DOC_TAG_DIR}")
  set(CGAL_DOC_DXY_DIR "${CMAKE_BINARY_DIR}/doc_dxy")
  file(MAKE_DIRECTORY "${CGAL_DOC_DXY_DIR}")

  set(CGAL_DOC_RESOURCE_DIR "${CMAKE_CURRENT_LIST_DIR}/resources")
  set(CGAL_DOC_BIBLIO_DIR "${CMAKE_CURRENT_LIST_DIR}/biblio")
  set(CGAL_DOC_SCRIPT_DIR "${CMAKE_CURRENT_LIST_DIR}/scripts")

  set(CGAL_DOC_HEADER ${CGAL_DOC_DXY_DIR}/header.html)
  configure_file(${CGAL_DOC_RESOURCE_DIR}/header.html ${CGAL_DOC_HEADER} @ONLY)
  set(CGAL_DOC_HEADER_PACKAGE ${CGAL_DOC_DXY_DIR}/header_package.html)
  configure_file(${CGAL_DOC_RESOURCE_DIR}/header_package.html ${CGAL_DOC_HEADER_PACKAGE} @ONLY)

  #Generate the bibtex file
  #this is needed also for BaseDoxyfile.in
  string(TIMESTAMP CGAL_BUILD_YEAR4 "%Y")
  string(TIMESTAMP CGAL_BUILD_YEAR2 "%y")
  string(TIMESTAMP CGAL_BUILD_MONTH "%m")

  if (${CGAL_BUILD_MONTH} GREATER 6)
    SET(CGAL_RELEASE_YEAR_ID "${CGAL_BUILD_YEAR2}b")
  else()
    SET(CGAL_RELEASE_YEAR_ID "${CGAL_BUILD_YEAR2}a")
  endif()

  ## generate how_to_cite files
  if(PYTHONINTERP_FOUND)
    execute_process(COMMAND ${PYTHON_EXECUTABLE}
                            ${CGAL_DOC_SCRIPT_DIR}/generate_how_to_cite.py
                            ${CMAKE_SOURCE_DIR}
                            ${CMAKE_BINARY_DIR}
                    RESULT_VARIABLE GENERATE_HOW_TO_CITE_RESULT)
    if(NOT GENERATE_HOW_TO_CITE_RESULT EQUAL "0")
      message(FATAL_ERROR "generate_how_to_cite did not exit correctly")
    endif()

    configure_file(${CMAKE_BINARY_DIR}/how_to_cite_cgal.bib.in ${CMAKE_BINARY_DIR}/how_to_cite_cgal.bib)
    configure_file(${CMAKE_BINARY_DIR}/how_to_cite_cgal.txt.in ${CMAKE_BINARY_DIR}/how_to_cite_cgal.txt)
    configure_file(${CMAKE_BINARY_DIR}/how_to_cite.html.in ${CMAKE_BINARY_DIR}/how_to_cite.html)
  endif()
  ##

  configure_file(${CGAL_DOC_RESOURCE_DIR}/BaseDoxyfile.in ${CGAL_DOC_DXY_DIR}/BaseDoxyfile)
  
  set(CGAL_DOC_DOXY_DEFAULT "${CGAL_DOC_DXY_DIR}/BaseDoxyfile")

  # pkglist_filter gets the path to the pkglist_filter of this source
  # directory.
  if(WIN32)
    configure_file(${CGAL_DOC_SCRIPT_DIR}/pkglist_filter.bat ${CMAKE_BINARY_DIR}/pkglist_filter.bat)
  endif()
  configure_file(${CGAL_DOC_SCRIPT_DIR}/pkglist_filter ${CMAKE_BINARY_DIR}/pkglist_filter)
  configure_file(${CGAL_DOC_SCRIPT_DIR}/pkglist_filter.py ${CMAKE_BINARY_DIR}/pkglist_filter.py)

  foreach(package ${CGAL_CONFIGURED_PACKAGES_NAMES})
    configure_doxygen_package(${package})
  endforeach()

  # hard-coded. this is not recognized as a package by the
  # build-system, because it doesn't have a package_description subdir.
  configure_doxygen_package("Miscellany")

  # Add a custom target "doc"
  add_custom_target(doc)
  add_custom_target(doc_pre)
  add_custom_target(doc_post)

  # do the main package manually, it isn't part of ${CGAL_CONFIGURED_PACKAGES_NAMES}
  configure_doxygen_package("Documentation")
  set_target_properties(Documentation_doc PROPERTIES FOLDER Documentation)

  # hard-code that doc depends on all packages
  foreach(depend ${DOCUMENTATION_DEPENDENCIES})
    add_dependencies(doc_pre ${depend}_internal_doxygen_run)
    add_dependencies(doc_post ${depend}_copy_doc_tags)
    add_dependencies(${depend}_copy_doc_tags doc_pre)
  endforeach()
  add_dependencies(doc_pre Documentation_internal_doxygen_run)
  add_dependencies(doc_post Documentation_copy_doc_tags)
  add_dependencies(Documentation_copy_doc_tags doc_pre)

  #total level doc dependencies
  add_dependencies(doc doc_post)

  if(PYTHONINTERP_FOUND)
    set(CGAL_DOC_TESTSUITE_SCRIPT "${CGAL_DOC_SCRIPT_DIR}/testsuite.py")

    add_custom_target(doc_with_postprocessing
      ${PYTHON_EXECUTABLE} ${CGAL_DOC_SCRIPT_DIR}/html_output_post_processing.py --output ${CGAL_DOC_OUTPUT_DIR} --resources ${CGAL_DOC_RESOURCE_DIR}
    )
    add_dependencies(doc_with_postprocessing doc)

    if(CGAL_DOC_CREATE_LOGS)
      add_custom_target(Documentation_test
        ${PYTHON_EXECUTABLE} ${CGAL_DOC_TESTSUITE_SCRIPT} --output-dir ${CGAL_DOC_OUTPUT_DIR} --doc-log-dir ${CGAL_DOC_LOG_DIR}
      )
      add_dependencies(Documentation_test doc)

      add_custom_target(Documentation_test_publish
        ${PYTHON_EXECUTABLE} ${CGAL_DOC_TESTSUITE_SCRIPT} --output-dir ${CGAL_DOC_OUTPUT_DIR} --doc-log-dir ${CGAL_DOC_LOG_DIR} --publish ${CGAL_DOC_PUBLISH_DIR} --do-copy-results
      )
      add_dependencies(Documentation_test_publish doc)

      set(CGAL_DOC_VERSION_H "/tmp/version.h" CACHE PATH "Path to CGAL/version.h")

      add_custom_target(doc_and_publish_testsuite
        ${PYTHON_EXECUTABLE} ${CGAL_DOC_TESTSUITE_SCRIPT} --output-dir ${CGAL_DOC_OUTPUT_DIR} --doc-log-dir ${CGAL_DOC_LOG_DIR} --publish ${CGAL_DOC_PUBLISH_DIR} --do-copy-results --cgal-version ${CGAL_DOC_VERSION_H} --version-to-keep 10
      )
      add_dependencies(doc_and_publish_testsuite doc_with_postprocessing)

    endif()
  endif()
  
  
  # add_custom_target(doc) dummy to depend on all docs, require to run
  # twice or something
endif()