ntopng/scripts/lua/modules/prefs_utils.lua

--
-- (C) 2014-22 - ntop.org
--
-- This file contains the description of all functions
-- used to trigger host alerts
local verbose = false
local prefs = ntop.getPrefs()
local info = ntop.getInfo()
local menu_subpages = require "prefs_menu"
show_advanced_prefs_key = "ntopng.prefs.show_advanced_prefs"
local have_nedge = ntop.isnEdge()
local skip_redis = false

-- ############################################

--
-- A menu is a list of menu entries
-- A menu entry is composed by the following fields:
--    - id: the subpage id
--    - label: a label to be shown into the menu
--    - entries: a list subpages (see belo)
--
-- The following optional fields can be specified
--
--    - advanced: if true, it should be only shown when advanced settings are enabled
--    - pro_only: if true, it should be only shown in ntopng pro version
--    - enterprise_only: if true, it should be only shown in ntopng enterprise version
--    - disabled: if true, the entry is hidden
--
-- A subpage is composed by the following fields:
--    - title: the subpage title
--    - description: the subpage description
--    - hidden: (optional) if true, this subpage is hidden
--

-- ############################################

DNS_PRESETS = {{
    id = "comodo_secure",
    label = "Comodo Secure DNS",
    url = "https://www.comodo.com/secure-dns/",
    primary_dns = "8.26.56.26",
    secondary_dns = "8.20.247.20"
}, {
    id = "dyn_internet_guide",
    label = "Dyn Internet Guide",
    url = "http://dyn.com/labs/dyn-internet-guide/",
    primary_dns = "216.146.35.35",
    secondary_dns = "216.146.36.36"
},
-- {id="fool_dns", label="FoolDNS", url="http://www.fooldns.com/fooldns-community/english-version/", primary_dns="87.118.111.215", secondary_dns="213.187.11.62"},
-- {id="greenteam_internet", label="GreenTeam Internet", url="http://members.greentm.co.uk/", primary_dns="81.218.119.11", secondary_dns="209.88.198.133"},
               {
    id = "opendns",
    label = "OpenDNS",
    url = "https://www.opendns.com/",
    primary_dns = "208.67.222.222",
    secondary_dns = "208.67.220.220"
}, {
    id = "opendns_familyshield",
    label = "OpenDNS - FamilyShield",
    url = "https://www.opendns.com/setupguide/?url=familyshield",
    primary_dns = "208.67.222.123",
    secondary_dns = "208.67.220.123",
    child_safe = true
}, {
    id = "quad9_security",
    label = "Quad 9: Security",
    url = "https://quad9.net",
    primary_dns = "9.9.9.9",
    secondary_dns = ""
}, {
    id = "google",
    label = "Google DNS",
    url = "https://developers.google.com/speed/public-dns",
    primary_dns = "8.8.8.8",
    secondary_dns = "8.8.4.4"
}, {
    id = "cloudflare",
    label = "Cloudflare DNS",
    url = "https://www.cloudflare.com/learning/dns/what-is-1.1.1.1",
    primary_dns = "1.1.1.1",
    secondary_dns = "1.0.0.1"
}, {
    id = "cleanbrowsing_security",
    label = "CleanBrowsing - Security",
    url = "https://cleanbrowsing.org",
    primary_dns = "185.228.168.9",
    secondary_dns = "185.228.169.9"
}, {
    id = "cleanbrwosing_adult",
    label = "CleanBrowsing - Adult Filter",
    url = "https://cleanbrowsing.org",
    primary_dns = "185.228.168.168",
    secondary_dns = "185.228.169.168",
    child_safe = true
}}

function isSubpageAvailable(subpage, show_advanced_prefs)
    if show_advanced_prefs == nil then
        show_advanced_prefs = toboolean(ntop.getPref(show_advanced_prefs_key))
    end
    if (subpage.hidden) or ((subpage.advanced) and (not show_advanced_prefs)) or
        ((subpage.pro_only) and (not ntop.isPro())) or
        (subpage.enterprise_l_only and (not info["version.enterprise_l_edition"]) and
            (not info["version.nedge_enterprise_edition"])) or
        ((subpage.enterprise_only) and (not info["version.enterprise_edition"]) and (not have_nedge)) or
        (subpage.nedge_hidden) and (have_nedge) then
        return false
    end

    return true
end

function prefsGetActiveSubpage(show_advanced_prefs, tab)
    local subpage_active = nil

    for _, subpage in ipairs(menu_subpages) do
        if not isSubpageAvailable(subpage, show_advanced_prefs) then
            subpage.hidden = true

            if subpage.id == tab then
                -- will set to default
                tab = nil
            end
        elseif subpage.id == tab then
            subpage_active = subpage
        end
    end

    -- default subpage
    if isEmptyString(tab) then
        -- Pick the first available subpage
        for _, subpage in ipairs(menu_subpages) do
            if isSubpageAvailable(subpage, show_advanced_prefs) then
                subpage_active = subpage
                tab = subpage.id
                break
            end
        end
    end

    return subpage_active, tab
end

function printMenuSubpages(tab)

    for _, subpage in ipairs(menu_subpages) do
        if not subpage.hidden then
            local url = ternary(subpage.disabled, "#",
                ntop.getHttpPrefix() .. [[/lua/admin/prefs.lua?tab=]] .. (subpage.id))
            print [[<a href="]]
            print(url)
            print [[" class="list-group-item list-group-item-action]]

            if (tab == subpage.id) then
                print(" active")
            elseif subpage.disabled then
                print(" disabled")
            end

            print [[">]]
            print(subpage.label)
            print [[</a>]]
        end
    end
end

-- ############################################

--- Notify ntopng upon preference changes
function notifyNtopng(key, value)
    if key == nil then
        return
    end
    -- notify runtime ntopng configuration changes
    if string.starts(key, 'toggle_logging_level') then
        if verbose then
            io.write('notifying ntopng upon logging level pref change\n')
        end
        ntop.setLoggingLevel(value)
    end
end

-- ############################################

local options_script_loaded = false
local options_ctr = 0

function prefsResolutionButtons(fmt, value, fixed_id, format_spec, max_val)
    local ctrl_id
    if fixed_id ~= nil then
        ctrl_id = fixed_id
    else
        ctrl_id = "options_group_" .. options_ctr
        options_ctr = options_ctr + 1
    end

    local res = makeResolutionButtons(format_spec or FMT_TO_DATA_TIME, ctrl_id, fmt, value, {
        classes = {"float-right"}
    }, max_val)

    res.value = truncate(res.value)

    print(res.html)
    print("<script>")
    if not options_script_loaded then
        print(res.init)
        options_script_loaded = true
    end
    print(res.js)
    print("</script>")

    return res.value
end

-- ############################################

-- Runtime preference

function prefsInputFieldPrefs(label, comment, prekey, key, default_value, _input_type, showEnabled, disableAutocomplete,
    allowURLs, extra)
    extra = extra or {}

    if (string.ends(prekey, ".")) then
        k = prekey .. key
    else
        k = prekey .. "." .. key
    end

    if not skip_redis then
        if (_POST[key] ~= nil) then
            v_s = _POST[key]
            v = tonumber(v_s)

            v_cache = ntop.getPref(k)
            value = v_cache
            if ((v_cache == nil) or (v_s ~= v_cache)) then
                if (v ~= nil and (v > 0) and (v <= 86400)) then
                    ntop.setPref(k, tostring(v))
                    value = v
                elseif (v_s ~= nil) then
                    if (allowURLs or (extra.pattern == getURLPattern())) then
                        v_s = string.gsub(v_s, "ldaps:__", "ldaps://")
                        v_s = string.gsub(v_s, "ldap:__", "ldap://")
                        v_s = string.gsub(v_s, "http:__", "http://")
                        v_s = string.gsub(v_s, "https:__", "https://")
                        v_s = string.gsub(v_s, "smtp:__", "smtp://")
                        v_s = string.gsub(v_s, "smtps:__", "smtps://")
                    end
                    ntop.setPref(k, v_s)
                    value = v_s
                end
                -- least but not last we asynchronously notify the runtime ntopng instance for changes
                notifyNtopng(key)
            end
        else
            local v_s = nil
            if not isEmptyString(prekey) then
                v_s = ntop.getPref(k)
            end
            value = v_s
            if ((v_s == nil) or (v_s == "") or (v_s == "nil")) then
                value = default_value
                if not isEmptyString(prekey) and (ntop.getPref(k) ~= tostring(default_value)) then
                    ntop.setPref(k, tostring(default_value))
                    notifyNtopng(key)
                end
            end
        end
    else
        value = default_value
    end -- skip_redis

    if ((showEnabled == nil) or (showEnabled == true)) then
        showEnabled = "table-row"
    else
        showEnabled = "none"
    end

    local attributes = {}

    if extra.min ~= nil then
        if extra.tformat ~= nil then
            attributes["data-min"] = extra.min
        else
            attributes["min"] = extra.min
        end
    end

    if extra.max ~= nil then
        if extra.tformat ~= nil then
            attributes["data-max"] = extra.max
        else
            attributes["max"] = extra.max
        end
    end

    if extra.minlength ~= nil then
        if extra.tformat ~= nil then
            attributes["data-minlength"] = extra.minlength
        else
            attributes["minlength"] = extra.minlength
        end
    end

    if extra.maxlength ~= nil then
        if extra.tformat ~= nil then
            attributes["data-maxlength"] = extra.maxlength
        else
            attributes["maxlength"] = extra.maxlength
        end
    end

    if extra.step ~= nil then
        if extra.tformat ~= nil then
            attributes["data-step"] = extra.step
        else
            attributes["step"] = extra.step
        end
    end

    if extra.disabled == true then
        attributes["disabled"] = "disabled"
    end
    if extra.required == true then
        attributes["required"] = ""
    end
    if extra.pattern ~= nil then
        attributes["pattern"] = extra.pattern
    end

    if (_input_type == "number") then
        attributes["required"] = "required"
    elseif (_input_type == "password") then
        -- disable chrome autocomplete
        attributes["autocomplete"] = "new-password"
    end

    local input_type = "text"
    if _input_type ~= nil then
        input_type = _input_type
    end
    print('<tr id="' .. key .. '" style="display: ' .. showEnabled .. ';"><td width=50%><strong>' .. label ..
              '</strong><p><small>' .. comment .. '</small></td>')

    local style = {}
    style["text-align"] = "right"
    style["margin-bottom"] = "0.5em"

    print [[
    <td align=right>
      <table class="table table-borderless form-group mb-3" style="margin-bottom: 0; min-width:22em;">
        <tr>
          <td width="100%;"></td>
          <td style="vertical-align:top;">]]
    if extra.tformat ~= nil then
        value = prefsResolutionButtons(extra.tformat, value, nil, extra.format_spec, extra.max)
    end

    if extra.width == nil then
        if _input_type == "number" then
            style["width"] = "8em"
        else
            style["width"] = "20em"
        end
        style["margin-left"] = "auto"
    else
        style["width"] = "15em"
    end
    style["margin-left"] = "auto"
    style["display"] = "inline"

    style = table.merge(style, extra.style)
    attributes = table.merge(attributes, extra.attributes)

    print [[
          </td>
          <td style="vertical-align:top; padding-left: 2em; white-space: nowrap;">
            <input id="id_input_]]
    print(key)
    print [[" type="]]
    print(input_type)
    print [[" class="form-control" ]]
    print(table.tconcat(attributes, "=", " ", nil, '"'))
    print [[ name="]]
    print(key)
    print [[" style="]]
    print(table.tconcat(style, ":", "; ", ";"))
    print [[" value="]]
    print(value .. '"')
    if disableAutocomplete then
        print(" autocomplete=\"off\"")
    end
    print [[/>]]
    print(extra.append or "")
    print [[
          </td>
        </tr>
        <tr>
          <td colspan="3" style="padding:0;">
            <div class="help-block with-errors text-end" style="height:1em;"></div>
          </td>
        </tr>
      </table>
  </td></tr>
]]

end

-- ############################################

function prefsDropdownFieldPrefs(label, comment, key, values, default_value, showEnabled, extra)
    extra = extra or {}

    if extra.save_pref and table.len(_POST) > 0 and isEmptyString(_POST[key]) == false and isEmptyString(extra.pref_key) ==
        false then
        ntop.setPref(extra.pref_key, _POST[key])
        default_value = _POST[key]
    end

    if ((showEnabled == nil) or (showEnabled == true)) then
        showEnabled = "table-row"
    else
        showEnabled = "none"
    end

    local attributes = {}

    if extra.disabled == true then
        attributes["disabled"] = "disabled"
    end
    if extra.required == true then
        attributes["required"] = ""
    end

    local input_type = "text"

    print('<tr id="' .. key .. '" style="display: ' .. showEnabled .. ';"><td width=50%><strong>' .. label ..
              '</strong><p><small>' .. comment .. '</small></td>')

    local style = {}
    style["text-align"] = "right"
    style["margin-bottom"] = "0.5em"

    print [[
    <td align=right>
      <table class="form-group mb-3" style="margin-bottom: 0; min-width:22em;">
        <tr>
          <td width="100%;"></td>]]

    if extra.width == nil then
        style["width"] = "20em"
        style["margin-left"] = "auto"
    else
        style["width"] = "15em"
    end
    style["margin-left"] = "auto"

    style = table.merge(style, extra.style)
    attributes = table.merge(attributes, extra.attributes)

    print [[
          <td style="vertical-align:top; padding-left: 2em;">
            <select id="id_input_]]
    print(key)
    print [[" class="form-select" ]]
    print(table.tconcat(attributes, "=", " ", nil, '"'))
    print [[ name="]]
    print(key)
    print [[" style="]]
    print(table.tconcat(style, ":", "; ", ";"))
    print [[" value="]]
    print((value or '') .. '"')
    print [[>]]
    if extra.keys == nil then
        for _, optname in pairs(values) do
            print("<option " .. ternary(optname == default_value, "selected", "") .. ">" .. optname .. "</option>")
        end
    else
        for idx, _ in pairs(values) do
            local key = extra.keys[idx]
            local val = values[idx]
            print("<option value=" .. key .. " " .. ternary(key == default_value, "selected", "") .. ">" .. val ..
                      "</option>")
        end
    end
    print [[
            </select>
          </td>
        </tr>
        <tr>
          <td colspan="3" style="padding:0;">
            <div class="help-block with-errors text-end" style="height:1em;"></div>
          </td>
        </tr>
      </table>
  </td></tr>
]]

end

-- ############################################

function prefsInformativeField(label, comment, showEnabled, extra)
    local extra = extra or {}
    extra["style"] = extra["style"] or {}
    extra["style"]["display"] = "none"
    prefsInputFieldPrefs(label, comment, "", "", "", nil, showEnabled, nil, nil, extra)
end

function toggleTableButton(label, comment, on_label, on_value, on_color, off_label, off_value, off_color, submit_field,
    redis_key, disabled)
    if (_POST[submit_field] ~= nil) then
        ntop.setPref(redis_key, _POST[submit_field])
        value = _POST[submit_field]
        notifyNtopng(submit_field)
    else
        value = ntop.getPref(redis_key)
    end
    if (disabled == true) then
        disabled = 'disabled = ""'
    else
        disabled = ""
    end

    -- Read it anyway to
    if (value == off_value) then
        rev_value = on_value
        on_active = "btn-secondary"
        off_active = "btn-" .. off_color .. " active"
    else
        rev_value = off_value
        on_active = "btn-" .. on_color .. " active"
        off_active = "btn-secondary"
    end

    if (label ~= "") then
        print('<tr><td width=50%><strong>' .. label .. '</strong><p><small>' .. comment ..
                  '</small></td><td align=right>\n')
    end
    print('<form method="post">\n<div class="btn-group btn-toggle">')
    print('<button type="submit" ' .. disabled .. ' class="btn btn-sm  ' .. on_active .. '">' .. on_label .. '</button>')
    print('<button ' .. disabled .. ' class="btn btn-sm ' .. off_active .. '">' .. off_label .. '</button></div>\n')
    print('<input id="csrf" name="csrf" type="hidden" value="' .. ntop.getRandomCSRFValue() .. '" />\n')
    print('<input type=hidden name=' .. submit_field .. ' value=' .. rev_value .. ' />\n')
    print('</form>\n')
    if (label ~= "") then
        print('</td></tr>')
    end

    return (value)
end

local function printNestedToSwitchLogic(nested_to_switch, submit_field)
    if ((type(nested_to_switch) ~= "table") or (table.empty(nested_to_switch))) then
        return
    end

    for _, item in ipairs(nested_to_switch) do
        print [[
      if(($("#]]
        print(submit_field)
        print [[").val() == "]]
        print(item.pref_enabled_value or "1")
        print [[") &&
         ($("#]]
        print(item.parent)
        print [[").val() == "]]
        print(item.parent_enabled_value)
        print [["))
        $("#]]
        print(item.input)
        print [[").css("display", "table-row");
      else
        $("#]]
        print(item.input)
        print [[").css("display", "none");
    ]]
    end
end

local function toggleTableButtonPrefs(label, comment, on_label, on_value, on_color, off_label, off_value, off_color,
    submit_field, redis_key, default_value, disabled, elementToSwitch, hideOn, showElement, nested_to_switch)

    local value

    if not skip_redis then
        value = ntop.getPref(redis_key)
        if (_POST[submit_field] ~= nil) then
            if ((value == nil) or (value ~= _POST[submit_field])) then
                ntop.setPref(redis_key, _POST[submit_field])
                value = _POST[submit_field]
                notifyNtopng(submit_field)
            end
        else
            if ((value == nil) or (value == "")) then
                if (default_value ~= nil) then
                    value = default_value
                else
                    value = off_value
                end
                ntop.setPref(redis_key, value)
                notifyNtopng(submit_field)
            end
        end
    else
        value = default_value
    end

    if (disabled == true) then
        disabled = 'disabled = ""'
    else
        disabled = ""
    end

    -- Read it anyway to
    if (value ~= off_value) then
        value = on_value
    end

    local objRow = ""
    if ((showElement ~= nil) and (showElement == false)) then
        objRow = " style=\"display:none\""
    else
        objRow = " style=\"display:table-row\""
    end
    if (label ~= "") then
        print('<tr id="row_' .. submit_field .. '"' .. objRow .. '><td width=50%><strong>' .. label ..
                  '</strong><p><small>' .. comment .. '</small></td><td align=right>\n')
    end

    print([[
    <div class="form-switch">
      <input ]] .. (value == off_value and '' or 'checked') .. [[ type="checkbox" class="form-check-input" id="check-]] ..
              submit_field .. [[">
      <label class="form-check-label" for="check-]] .. submit_field .. [["></label>
      <input hidden id="input-]] .. submit_field .. [[" name="]] .. submit_field .. [[" value="]] .. value .. [[">
  ]])
    print([[</div>]])
    if (label ~= "") then
        print('</td></tr>')
    end
    print('<script type="text/javascript">')

    print([[
    $("#check-]] .. submit_field .. [[").change(function(e) {

      const value = $(this).is(":checked");

      if (value) {
        ]] .. submit_field .. [[_functionOn();
      }
      else {
        ]] .. submit_field .. [[_functionOff();
      }
    });
  ]])

    print [[function ]]
    print(submit_field)
    print [[_functionOn(){]]
    print([[$(`#input-]] .. submit_field .. [[`).val("]] .. on_value .. [[");]])

    if elementToSwitch ~= nil then
        for element = 1, #elementToSwitch do
            if ((hideOn == nil) or (hideOn == false)) then
                print('$("#' .. elementToSwitch[element] .. '").css("display","table-row");')
            else
                print('$("#' .. elementToSwitch[element] .. '").css("display","none");')
            end
        end
    end

    printNestedToSwitchLogic(nested_to_switch, "input-" .. submit_field)

    print [[
  }
  ]]
    print [[
  function ]]
    print(submit_field)
    print [[_functionOff(){]]

    print([[$(`#input-]] .. submit_field .. [[`).val("]] .. off_value .. [["); ]])

    if elementToSwitch ~= nil then
        for element = 1, #elementToSwitch do
            if ((hideOn == nil) or (hideOn == false)) then
                print('$("#' .. elementToSwitch[element] .. '").css("display","none");')
            else
                print('$("#' .. elementToSwitch[element] .. '").css("display","table-row");')
            end
        end
    end

    printNestedToSwitchLogic(nested_to_switch, "input-" .. submit_field)

    print [[
  }]]
    print('</script>\n')
    return (value)
end

local function get_pref_redis_key(options)
    local prefix = options.redis_prefix or "ntopng.prefs."
    return prefix .. ternary(options.pref ~= nil, options.pref, options.field)
end

function prefsToggleButton(subpage_active, params)
    local defaults = {
        to_switch = {}, -- a list of elements to be switched on or off
        on_text = "On", -- The text when the button is on
        on_value = "1", -- The value when the button is on
        on_class = "success", -- The css class when the button is on
        off_text = "Off", -- The text when the button is off
        off_value = "0", -- The value when the button is off
        off_class = "danger", -- The css class when the button is off
        reverse_switch = false, -- If true, elements are hidden when the item is enabled
        nested_to_switch = {} -- Similar to "to_switch" but for nested items
    }

    local options = table.merge(defaults, params)
    local redis_key = get_pref_redis_key(options)

    -- used for debugging purpose:
    -- if (subpage_active.entries[options.field] ~= nil) then
    --  traceError(TRACE_ERROR, TRACE_CONSOLE, "Missing entry '" .. options.field .. "' inside entries field")
    -- end

    return toggleTableButtonPrefs(params.title or subpage_active.entries[options.field].title,
        (params.description or subpage_active.entries[options.field].description) ..
            (params.content or subpage_active.entries[options.field].content or ""), options.on_text, options.on_value,
        options.on_class, options.off_text, options.off_value, options.off_class, options.field, redis_key,
        options.default, options.disabled, options.to_switch, options.reverse_switch, not options.hidden,
        options.nested_to_switch)
end

function multipleTableButtonPrefs(label, comment, array_labels, array_values, default_value, selected_color,
    submit_field, redis_key, disabled, elementToSwitch, showElementArray, nested_to_switch, showElement, initialValue,
    toggleElementArray)
    local value
    local disabled_attr

    if not skip_redis then
        if (_POST[submit_field] ~= nil) then
            local old_v = ntop.getPref(redis_key)
            value = _POST[submit_field]

            if old_v ~= _POST[submit_field] then
                ntop.setPref(redis_key, _POST[submit_field])
                notifyNtopng(submit_field)
            end
        else
            value = initialValue or ntop.getPref(redis_key)

            if (value == "") then
                if (default_value ~= nil) then
                    ntop.setPref(redis_key, default_value)
                    value = default_value
                end
            end
        end
    else
        value = default_value
    end

    if (disabled == true) then
        disabled = "disabled"
        disabled_attr = ' disabled="disabled"'
    else
        disabled = ""
        disabled_attr = ""
    end

    local objRow = ""
    if ((showElement ~= nil) and (showElement == false)) then
        objRow = " style=\"display:none\""
    else
        objRow = " style=\"display:table-row\""
    end
    if (value ~= nil) then
        if (label ~= "") then
            print('<tr id="row_' .. submit_field .. '"' .. objRow .. '><td width=50%><strong>' .. label ..
                      '</strong><p><small>' .. comment .. '</small></td><td align=right>\n')
        end
        print('<div class="btn-group" role="group">')

        for nameCount = 1, #array_labels do
            local type_button = "btn-secondary"
            if (value == array_values[nameCount]) then
                local color
                if type(selected_color) == "table" then
                    color = selected_color[nameCount]
                else
                    color = selected_color
                end
                type_button = "btn-" .. color .. "  active"
            end

            print('<input type="radio" name="' .. submit_field .. '" id="id_' .. submit_field .. '_' ..
                      array_values[nameCount] .. '" value="' .. array_values[nameCount] ..
                      '" class="btn-check btn-primary" ' .. disabled_attr .. '>\n')
            print('<label class="btn btn-sm ' .. type_button .. '"  for="id_' .. submit_field .. '_' ..
                      array_values[nameCount] .. '">' .. array_labels[nameCount] .. '</label>\n')
        end
        print('</div>\n')
        print('<script>\n')

        -- showElementArray can be either:
        --  1. a simple table (e.g. {true, false}): it affects all the elements in elementToSwitch
        --  2. a nested table (e.g. {{true, false}, {false, false}}): each element in the table
        --     affects the corresponding element in the elementToSwitch (e.g. {true, false} affects
        --     elementToSwitch[1], whereas {false, false} affects elementToSwitch[2])
        if (showElementArray and (type(showElementArray[1]) ~= "table")) then
            -- This is simple table (case 1.) above, convert it to case 2 to handle
            -- both cases consinstenly below.
            showElementArray = {showElementArray}
        end

        for nameCount = 1, #array_labels do
            print('$(`label[for="id_' .. submit_field .. '_' .. array_values[nameCount] .. '"]`).click(function() {\n')
            print(' var field = $(\'#id-toggle-' .. submit_field .. '\');\n')
            print(' var oldval = field.val(); ')
            print(' field.val("' .. array_values[nameCount] .. '").trigger("change");\n')

            for indexLabel = 1, #array_labels do
                local color
                if type(selected_color) == "table" then
                    color = selected_color[indexLabel]
                else
                    color = selected_color
                end

                print [[ let class_]]
                print(array_values[indexLabel])
                print [[ = $(`label[for="id_]]
                print(submit_field .. '_')
                print(array_values[indexLabel])
                print [["]`);
        class_]]
                print(array_values[indexLabel])
                print [[.removeAttr("class");]]
                if (array_values[indexLabel] == array_values[nameCount]) then
                    print [[class_]]
                    print(array_values[indexLabel])
                    print [[.attr("class", "btn btn-sm btn-]]
                    print(color)
                    print [[ active");]]
                else
                    print [[class_]]
                    print(array_values[indexLabel])
                    print [[.attr("class", "btn btn-sm btn-secondary");]]
                end
            end

            -- Show/Hide all the elementToSwitch items at once
            if (showElementArray ~= nil) then
                for indexSwitch = 1, #showElementArray[1] do
                    if (indexSwitch == nameCount) then
                        if elementToSwitch ~= nil then
                            for element = 1, #elementToSwitch do
                                -- Try to get the element-specific configuration if available,
                                -- otherwise fallback to the default configuration (at index 1)
                                local to_apply = showElementArray[element] or showElementArray[1]

                                if (to_apply[indexSwitch] == true) then
                                    -- NOTE: this is executed into the js change callback
                                    print('$("#' .. elementToSwitch[element] .. '").css("display","table-row");\n')
                                else
                                    -- NOTE: this is executed into the js change callback
                                    print('$("#' .. elementToSwitch[element] .. '").css("display","none");\n')
                                end
                            end
                        end
                    end
                end
                -- Show/Hide all the elementToSwitch selectively
            elseif (toggleElementArray ~= nil) then
                for indexSwitch = 1, #toggleElementArray do
                    if (indexSwitch == nameCount) then
                        if elementToSwitch ~= nil then
                            for element = 1, #elementToSwitch do
                                if (toggleElementArray[indexSwitch][element] == true) then
                                    -- NOTE: this is executed into the js change callback
                                    print('$("#' .. elementToSwitch[element] .. '").css("display","table-row");\n')
                                else
                                    -- NOTE: this is executed into the js change callback
                                    print('$("#' .. elementToSwitch[element] .. '").css("display","none");\n')
                                end
                            end
                        end
                    end
                end
            end

            printNestedToSwitchLogic(nested_to_switch, "id-toggle-" .. submit_field)

            print('});\n')
        end
        print('</script>\n')
        if (label ~= "") then
            print('</td></tr>')
        end
    end

    return (value)
end

function loggingSelector(label, comment, submit_field, redis_key)
    prefs = ntop.getPrefs()
    if prefs.has_cmdl_trace_lvl then
        return
    end

    if (_POST[submit_field] ~= nil) then
        ntop.setCache(redis_key, _POST[submit_field])
        value = _POST[submit_field]
        notifyNtopng(submit_field, _POST[submit_field])
    else
        value = ntop.getCache(redis_key)
    end

    if value == "" or value == nil then
        value = "normal"
    end

    local logging_values = {"trace", "debug", "info", "normal", "warning", "error"}
    local color_map = {"secondary", "success", "info", "primary", "warning", "danger"}
    local logging_keys = {}
    local color = "secondary"

    for i, v in ipairs(logging_values) do
        logging_keys[i] = firstToUpper(v)
    end

    multipleTableButtonPrefs("Log level", "Choose the runtime logging level.", logging_keys, logging_values, value,
        color_map, submit_field, redis_key)

    return (value)
end

function printPageSection(section_name)
    print('<thead class="table-primary"><tr><th colspan=2 class="info">' .. section_name .. '</th></tr></thead>')
end

function printSaveButton(some_content)
    print('<tr><td colspan=2 style="text-align:right;">' .. (some_content or "") ..
              '<button type="submit" class="btn btn-primary" style="width:115px" disabled="disabled">' .. i18n("save") ..
              '</button></td></tr>')
end

function prefsSkipRedis(skip)
    skip_redis = skip
end