Moving files:

wireplumber/scripts/default-nodes/state-default-nodes.lua

@@ -0,0 +1,199 @@
+-- WirePlumber
+--
+-- Copyright © 2022 Collabora Ltd.
+--
+-- SPDX-License-Identifier: MIT
+
+-- the script states the default nodes from the user preferences, it has hooks
+-- which stores the user preferences(it stores not just the current preference
+-- but all the previous preferences) in to the state file, retrives them from
+-- state file during the bootup, finally it has a hook which finds a default
+-- node out of the user preferences
+
+log = Log.open_topic ("s-default-nodes")
+
+nutils = require ("node-utils")
+
+-- the state storage
+state = nil
+state_table = nil
+
+find_stored_default_node_hook = SimpleEventHook {
+  name = "default-nodes/find-stored-default-node",
+  interests = {
+    EventInterest {
+      Constraint { "event.type", "=", "select-default-node" },
+    },
+  },
+  execute = function (event)
+    local props = event:get_properties ()
+    local available_nodes = event:get_data ("available-nodes")
+    local selected_prio = event:get_data ("selected-node-priority") or 0
+    local selected_node = event:get_data ("selected-node")
+
+    available_nodes = available_nodes and available_nodes:parse ()
+    if not available_nodes then
+      return
+    end
+
+    local stored = collectStored (props ["default-node.type"])
+
+    -- Check if any of the available nodes matches any of the configured
+    for _, node_props in ipairs (available_nodes) do
+      local name = node_props ["node.name"]
+
+      for i, v in ipairs (stored) do
+        if name == v then
+          local priority = nutils.get_session_priority (node_props)
+          priority = priority + 20001 - i
+
+          if priority > selected_prio then
+            selected_prio = priority
+            selected_node = name
+          end
+
+          break
+        end
+      end
+    end
+
+    if selected_node then
+      event:set_data ("selected-node-priority", selected_prio)
+      event:set_data ("selected-node", selected_node)
+    end
+  end
+}
+
+store_configured_default_nodes_hook = SimpleEventHook {
+  name = "default-nodes/store-configured-default-nodes",
+  interests = {
+    EventInterest {
+      Constraint { "event.type", "=", "metadata-changed" },
+      Constraint { "metadata.name", "=", "default" },
+      Constraint { "event.subject.key", "c", "default.configured.audio.sink",
+          "default.configured.audio.source", "default.configured.video.source"
+      },
+    },
+  },
+  execute = function (event)
+    local props = event:get_properties ()
+    -- get the part after "default.configured." (= 19 chars)
+    local def_node_type = props ["event.subject.key"]:sub (20)
+    local new_value = props ["event.subject.value"]
+    local new_stored = {}
+
+    if new_value then
+      new_value = Json.Raw (new_value):parse () ["name"]
+    end
+
+    if new_value then
+      local stored = collectStored (def_node_type)
+      local pos = #stored + 1
+
+      -- find if the curent configured value is already in the stack
+      for i, v in ipairs (stored) do
+        if v == new_value then
+          pos = i
+          break
+        end
+      end
+
+      -- insert at the top and shift the remaining to fill the gap
+      new_stored [1] = new_value
+      if pos > 1 then
+        table.move (stored, 1, pos-1, 2, new_stored)
+      end
+      if pos < #stored then
+        table.move (stored, pos+1, #stored, pos+1, new_stored)
+      end
+    end
+
+    updateStored (def_node_type, new_stored)
+  end
+}
+
+-- set initial values
+metadata_added_hook = SimpleEventHook {
+  name = "default-nodes/metadata-added",
+  interests = {
+    EventInterest {
+      Constraint { "event.type", "=", "metadata-added" },
+      Constraint { "metadata.name", "=", "default" },
+    },
+  },
+  execute = function (event)
+    local types = { "audio.sink", "audio.source", "video.source" }
+    local source = event:get_source ()
+    local om = source:call ("get-object-manager", "metadata")
+    local metadata = om:lookup { Constraint { "metadata.name", "=", "default" } }
+
+    for _, t in ipairs (types) do
+      local v = state_table ["default.configured." .. t]
+      if v then
+        metadata:set (0, "default.configured." .. t, "Spa:String:JSON",
+                      Json.Object { ["name"] = v }:to_string ())
+      end
+    end
+  end
+}
+
+-- Collect all the previously configured node names from the state file
+function collectStored (def_node_type)
+  local stored = {}
+  local key_base = "default.configured." .. def_node_type
+  local key = key_base
+
+  local index = 0
+  repeat
+    local v = state_table [key]
+    table.insert (stored, v)
+    key = key_base .. "." .. tostring (index)
+    index = index + 1
+  until v == nil
+
+  return stored
+end
+
+-- Store the given node names in the state file
+function updateStored (def_node_type, stored)
+  local key_base = "default.configured." .. def_node_type
+  local key = key_base
+
+  local index = 0
+  for _, v in ipairs (stored) do
+    state_table [key] = v
+    key = key_base .. "." .. tostring (index)
+    index = index + 1
+  end
+
+  -- erase the rest, if any
+  repeat
+    local v = state_table [key]
+    state_table [key] = nil
+    key = key_base .. "." .. tostring (index)
+    index = index + 1
+  until v == nil
+
+  state:save_after_timeout (state_table)
+end
+
+function toggleState (enable)
+  if enable and not state then
+    state = State ("default-nodes")
+    state_table = state:load ()
+    find_stored_default_node_hook:register ()
+    store_configured_default_nodes_hook:register ()
+    metadata_added_hook:register ()
+  elseif not enable and state then
+    state = nil
+    state_table = nil
+    find_stored_default_node_hook:remove ()
+    store_configured_default_nodes_hook:remove ()
+    metadata_added_hook:remove ()
+  end
+end
+
+Settings.subscribe ("node.restore-default-targets", function ()
+  toggleState (Settings.get_boolean ("node.restore-default-targets"))
+end)
+toggleState (Settings.get_boolean ("node.restore-default-targets"))