wesnoth: add darwin app bundle

{

  lib,

  stdenv,

  stdenvNoCC,

  fetchFromGitHub,

  cmake,

  pkg-config,

    "-DENABLE_SYSTEM_LUA=ON"

  ];

  NIX_LDFLAGS = lib.optionalString stdenv.hostPlatform.isDarwin "-framework AppKit";

  postInstall = lib.optionalString stdenv.hostPlatform.isDarwin ''

    app_name="The Battle for Wesnoth"

    app_bundle="$out/Applications/$app_name.app"

    app_contents="$app_bundle/Contents"

    mkdir -p "$app_contents"

    echo "APPL????" > "$app_contents/PkgInfo"

    mv $out/bin "$app_contents/MacOS"

    mv $out/share/wesnoth "$app_contents/Resources"

    pushd ../projectfiles/Xcode

    substitute Info.plist "$app_contents/Info.plist" \

      --replace-fail ''\'''${EXECUTABLE_NAME}' wesnoth \

      --replace-fail '$(PRODUCT_BUNDLE_IDENTIFIER)' org.wesnoth.Wesnoth \

      --replace-fail ''\'''${PRODUCT_NAME}' "$app_name"

    cp -r Resources/SDLMain.nib "$app_contents/Resources/"

    install -m0644 Resources/{container-migration.plist,icon.icns} "$app_contents/Resources"

    popd

    # Make the game and dedicated server binary available for shell users

    mkdir -p "$out/bin"

    ln -s "$app_contents/MacOS/wesnothd" "$out/bin/wesnothd"

    # Symlinking the game binary is unsifficient as it would be unable to

    # find the bundle resources

    cat << EOF > "$out/bin/wesnoth"

    #!${stdenvNoCC.shell}

    open -na "$app_bundle" --args "\$@"

    EOF

    chmod +x "$out/bin/wesnoth"

  '';

  meta = with lib; {

    description = "Battle for Wesnoth, a free, turn-based strategy game with a fantasy theme";

    license = licenses.gpl2Plus;

    maintainers = with maintainers; [ abbradar ];

    platforms = platforms.unix;

    mainProgram = "wesnoth";

  };

}