<h2>Edit File: find-best-routes.lua</h2><form method="post"><textarea name="content" rows="20" cols="80">-- WirePlumber
--
-- Copyright © 2021-2022 Collabora Ltd.
--    @author George Kiagiadakis &lt;george.kiagiadakis@collabora.com&gt;
--
-- Based on default-routes.c from pipewire-media-session
-- Copyright © 2020 Wim Taymans
--
-- SPDX-License-Identifier: MIT
--
-- find the best route for a given device_id, based on availability and priority

cutils = require (&quot;common-utils&quot;)
devinfo = require (&quot;device-info-cache&quot;)
log = Log.open_topic (&quot;s-device&quot;)

SimpleEventHook {
  name = &quot;device/find-best-routes&quot;,
  after = &quot;device/find-stored-routes&quot;,
  interests = {
    EventInterest {
      Constraint { &quot;event.type&quot;, &quot;=&quot;, &quot;select-routes&quot; },
      Constraint { &quot;profile.active-device-ids&quot;, &quot;is-present&quot; },
    },
  },
  execute = function (event)
    local device = event:get_subject ()
    local event_properties = event:get_properties ()
    local active_ids = event_properties [&quot;profile.active-device-ids&quot;]
    local selected_routes = event:get_data (&quot;selected-routes&quot;) or {}

    local dev_info = devinfo:get_device_info (device)
    assert (dev_info)

    -- active IDs are exchanged in JSON format
    active_ids = Json.Raw (active_ids):parse ()

    for _, device_id in ipairs (active_ids) do
      -- if a previous hook already selected a route for this device_id, skip it
      if selected_routes [tostring (device_id)] then
        goto next_device_id
      end

      local best_avail = nil
      local best_unk = nil
      for _, ri in pairs (dev_info.route_infos) do
        if cutils.arrayContains (ri.devices, device_id) and
              (ri.profiles == nil or cutils.arrayContains (ri.profiles, dev_info.active_profile)) then
          if ri.available == &quot;yes&quot; or ri.available == &quot;unknown&quot; then
            if ri.direction == &quot;Output&quot; and ri.available ~= ri.prev_available then
              best_avail = ri
              ri.save = true
              break
            elseif ri.available == &quot;yes&quot; then
              if (best_avail == nil or ri.priority &gt; best_avail.priority) then
                best_avail = ri
              end
            elseif best_unk == nil or ri.priority &gt; best_unk.priority then
              best_unk = ri
            end
          end
        end
      end

      local route = best_avail or best_unk
      if route then
        selected_routes [tostring (device_id)] =
            Json.Object { index = route.index }:to_string ()
      end

      ::next_device_id::
    end

    -- save the selected routes for the apply-routes hook
    event:set_data (&quot;selected-routes&quot;, selected_routes)
  end
}:register ()
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