# SPDX-FileCopyrightText: 2007-2009 Kitware, Inc.
# SPDX-FileCopyrightText: 2007 Alexander Neundorf <neundorf@kde.org>
# SPDX-FileCopyrightText: 2014 Aurélien Gâteau <agateau@kde.org>
#
# SPDX-License-Identifier: BSD-3-Clause

#[=======================================================================[.rst:
ECMPoQmTools
------------

This module provides the ``ecm_process_po_files_as_qm`` and
``ecm_install_po_files_as_qm`` functions for generating QTranslator (.qm)
catalogs from Gettext (.po) catalogs, and the ``ecm_create_qm_loader``
function for generating the necessary code to load them in a Qt application
or library.

::

  ecm_process_po_files_as_qm(<lang> [ALL]
                             [INSTALL_DESTINATION <install_destination>]
                             PO_FILES <pofile> [<pofile> [...]])

Compile .po files into .qm files for the given language.

If ``INSTALL_DESTINATION`` is given, the .qm files are installed in
``<install_destination>/<lang>/LC_MESSAGES``. Typically,
``<install_destination>`` is set to ``share/locale``.

``ecm_process_po_files_as_qm`` creates a "translations" target. This target
builds all .po files into .qm files.  If ``ALL`` is specified, these rules are
added to the "all" target (and so the .qm files will be built by default).

::

  ecm_create_qm_loader(<sources_var_name(|target (since 5.83))> <catalog_name>)

Generates C++ code which ensures translations are automatically loaded at
startup. The generated files are appended to the variable named
``<sources_var_name>`` or, if the first argument is a target (since 5.83), to
the ``SOURCES`` property of ``<target>``. Any target must be created with
``add_executable()`` or ``add_library()`` and not be an alias.

It assumes that the .qm file for the language code ``<lang>`` is installed as
``<sharedir>/locale/<lang>/LC_MESSAGES/<catalog_name>.qm``, where
``<sharedir>`` is one of the directories given by the ``GenericDataLocation``
of ``QStandardPaths``.

Typical usage is like:

.. code-block:: cmake

  set(mylib_SRCS foo.cpp bar.cpp)
  ecm_create_qm_loader(mylib_SRCS mycatalog)
  add_library(mylib ${mylib_SRCS})

  # Or, since 5.83:
  add_library(mylib foo.cpp bar.cpp)
  ecm_create_qm_loader(mylib mycatalog)

::

  ecm_install_po_files_as_qm(<podir>)

Searches for .po files and installs them to the standard location.

This is a convenience function which relies on all .po files being kept in
``<podir>/<lang>/``, where ``<lang>`` is the language the .po files are
written in.

For example, given the following directory structure::

 po/
   fr/
     mylib.po

``ecm_install_po_files_as_qm(po)`` compiles ``mylib.po`` into ``mylib.qm`` and
installs it in ``<install_destination>/fr/LC_MESSAGES``.
``<install_destination>`` defaults to ``${LOCALE_INSTALL_DIR}`` if defined,
otherwise it uses ``${CMAKE_INSTALL_LOCALEDIR}`` if that is defined, otherwise
it uses ``share/locale``.

Since pre-1.0.0.
#]=======================================================================]

cmake_policy(VERSION 3.16)

include(${CMAKE_CURRENT_LIST_DIR}/QtVersionOption.cmake)
option(KF_SKIP_PO_PROCESSING "Skip processing of po files" OFF)

# Copied from FindGettext.cmake
function(_ecm_qm_get_unique_target_name _name _unique_name)
   set(propertyName "_ECM_QM_UNIQUE_COUNTER_${_name}")
   get_property(currentCounter GLOBAL PROPERTY "${propertyName}")
   if(NOT currentCounter)
      set(currentCounter 1)
   endif()
   set(${_unique_name} "${_name}_${currentCounter}" PARENT_SCOPE)
   math(EXPR currentCounter "${currentCounter} + 1")
   set_property(GLOBAL PROPERTY ${propertyName} ${currentCounter} )
endfunction()


function(ecm_create_qm_loader sourcesvar_or_target catalog_name)
    if (TARGET ${sourcesvar_or_target})
        get_target_property(target_type ${sourcesvar_or_target} TYPE)
        set(allowed_types "EXECUTABLE" "STATIC_LIBRARY" "MODULE_LIBRARY" "SHARED_LIBRARY" "OBJECT_LIBRARY" "INTERFACE_LIBRARY")
        if (NOT target_type IN_LIST allowed_types)
            message(FATAL_ERROR "Target argument passed to ecm_create_qm_loader is not an executable or a library: ${appsources_or_target}")
        endif()
        get_target_property(aliased_target ${sourcesvar_or_target} ALIASED_TARGET)
        if(aliased_target)
            message(FATAL_ERROR "Target argument passed to ecm_create_qm_loader must not be an alias: ${sourcesvar_or_target}")
        endif()
    endif()
    set(loader_base ${CMAKE_CURRENT_BINARY_DIR}/ECMQmLoader-${catalog_name})

    set(QM_LOADER_CATALOG_NAME "${catalog_name}")

    set(QM_LOADER_CPP_FILE "${loader_base}.cpp")
    configure_file(
        ${ECM_MODULE_DIR}/ECMQmLoader.cpp.in
        ${QM_LOADER_CPP_FILE}
        @ONLY
    )
    if (TARGET ${sourcesvar_or_target})
        target_sources(${sourcesvar_or_target} PRIVATE ${QM_LOADER_CPP_FILE})
    else()
        set(${sourcesvar_or_target} "${${sourcesvar_or_target}}" ${QM_LOADER_CPP_FILE} PARENT_SCOPE)
    endif()
endfunction()


function(ecm_process_po_files_as_qm lang)
    if (KF_SKIP_PO_PROCESSING)
      return()
    endif()
    # Parse arguments
    set(options ALL)
    set(oneValueArgs INSTALL_DESTINATION)
    set(multiValueArgs PO_FILES)
    cmake_parse_arguments(ARGS "${options}" "${oneValueArgs}" "${multiValueArgs}" ${ARGN})

    if(ARGS_UNPARSED_ARGUMENTS)
        message(FATAL_ERROR "Unknown keywords given to ecm_process_po_files_as_qm(): \"${ARGS_UNPARSED_ARGUMENTS}\"")
    endif()

    if(NOT ARGS_PO_FILES)
        message(FATAL_ERROR "ecm_process_po_files_as_qm() must be called with PO_FILES argument")
    endif()

    # Find lrelease and lconvert
    if (QT_MAJOR_VERSION EQUAL "5")
        find_package(Qt5LinguistTools CONFIG REQUIRED)
    else()
        find_package(Qt6 COMPONENTS LinguistTools CONFIG REQUIRED)
    endif()

    if(TARGET Qt${QT_MAJOR_VERSION}::lconvert)
        set(lconvert_executable Qt${QT_MAJOR_VERSION}::lconvert)
    else()
        # Qt < 5.3.1 does not define Qt5::lconvert
        get_target_property(lrelease_location Qt5::lrelease LOCATION)
        get_filename_component(lrelease_path ${lrelease_location} DIRECTORY)
        find_program(lconvert_executable
            NAMES lconvert-qt5 lconvert
            PATHS ${lrelease_path}
            NO_DEFAULT_PATH
            )
    endif()

    # Create commands to turn po files into qm files
    set(qm_files)
    foreach (po_file ${ARGS_PO_FILES})
        get_filename_component(po_file ${po_file} ABSOLUTE)
        get_filename_component(filename_base ${po_file} NAME_WE)

        # Use own ECMPoQm/ subfolder for processing the files, to avoid cluttering
        # the default build dir as well as potential file/dir name clashes from
        # other build artifacts.
        # Include ${lang} in build dir because we might be called multiple times
        # with the same ${filename_base}
        set(build_dir ${CMAKE_CURRENT_BINARY_DIR}/ECMPoQm/${lang})
        set(ts_file ${build_dir}/${filename_base}.ts)
        set(qm_file ${build_dir}/${filename_base}.qm)

        file(MAKE_DIRECTORY ${build_dir})

        # lconvert from .po to .ts, then lrelease from .ts to .qm.
        add_custom_command(OUTPUT ${qm_file}
            COMMAND ${lconvert_executable}
                ARGS -i ${po_file} -o ${ts_file} -target-language ${lang}
            COMMAND Qt${QT_MAJOR_VERSION}::lrelease
                ARGS -removeidentical -nounfinished -silent ${ts_file} -qm ${qm_file}
            DEPENDS ${po_file}
            )
        if (ARGS_INSTALL_DESTINATION)
            install(
                FILES ${qm_file}
                DESTINATION ${ARGS_INSTALL_DESTINATION}/${lang}/LC_MESSAGES
            )
        endif()
        list(APPEND qm_files ${qm_file})
    endforeach()

    # Hook qm files to targets
    if(NOT TARGET translations)
        add_custom_target(translations)
    endif()

    _ecm_qm_get_unique_target_name(translations target_name)

    if (ARGS_ALL)
        add_custom_target(${target_name} ALL DEPENDS ${qm_files})
    else()
        add_custom_target(${target_name} DEPENDS ${qm_files})
    endif()

    add_dependencies(translations ${target_name})
endfunction()


function(ecm_install_po_files_as_qm podir)
    if (LOCALE_INSTALL_DIR)
        set(install_destination "${LOCALE_INSTALL_DIR}")
    elseif (CMAKE_INSTALL_LOCALEDIR)
        set(install_destination "${CMAKE_INSTALL_LOCALEDIR}")
    else()
        set(install_destination share/locale)
    endif()

    get_filename_component(absolute_podir ${podir} ABSOLUTE)

    # we try to find the po directory in the binary directory, in case it was downloaded
    # using ECM
    if (NOT (EXISTS "${absolute_podir}" AND IS_DIRECTORY "${absolute_podir}"))
        get_filename_component(absolute_podir ${CMAKE_BINARY_DIR}/${podir} ABSOLUTE)
    endif()

    if (NOT (EXISTS "${absolute_podir}" AND IS_DIRECTORY "${absolute_podir}"))
        # Nothing to do if there's no podir and it would create an empty
        # LOCALE_INSTALL_DIR in that case.
        return()
    endif()

    file(GLOB po_files "${absolute_podir}/*/*.po")
    foreach(po_file ${po_files})
        get_filename_component(po_dir ${po_file} DIRECTORY)
        get_filename_component(lang ${po_dir} NAME)
        ecm_process_po_files_as_qm(
            ${lang} ALL
            PO_FILES ${po_file}
            INSTALL_DESTINATION ${install_destination}
        )
    endforeach()
endfunction()
