feat(audio-switcher): support grouped outputs (#163)

audio-switcher/README.md

@@ -2,8 +2,9 @@
 
 Audio Switcher puts PipeWire inputs, outputs, volume controls, and Bluetooth
 audio handoff in one compact Noctalia panel. Devices can be renamed or hidden,
-and compositor keybinds can cycle devices or connect a specific Bluetooth
-device by its persistent number.
+multiple outputs can be grouped for simultaneous playback, and compositor
+keybinds can cycle devices or connect a specific Bluetooth device by its
+persistent number.
 
 ![Audio Switcher panel](screenshots/panel.webp)
 
@@ -23,6 +24,8 @@ through visible inputs. Scrolling over it changes the output volume.
 Install `pactl`, `bluetoothctl`, and `sleep` on `PATH`. On Arch Linux they are
 provided by the `libpulse`, `bluez-utils`, and `coreutils` packages respectively.
 PipeWire's PulseAudio compatibility service and BlueZ must be running.
+Output grouping also requires PulseAudio's or PipeWire Pulse's
+`module-combine-sink`.
 
 ## Usage
 
@@ -42,6 +45,12 @@ change a Bluetooth keybind number. The number is assigned automatically after a
 device connects successfully for the first time and can then be changed. Hidden
 devices remain available in the panel but are skipped by cycling commands.
 
+To play through multiple outputs at once, open **Outputs**, choose **Group
+outputs**, select at least two available physical outputs, then choose **Create
+group**. The combined output becomes the default and current playback streams
+move to it. Use **Disband** on its row to remove it; if it is active, playback
+moves to the first available member before removal.
+
 Use the settings button in the panel header to open Noctalia's plugin settings.
 
 ## Settings
@@ -98,6 +107,12 @@ other Bluetooth audio devices connected to this computer. It cannot disconnect
 the target from another computer or phone; that device must release the target
 first unless it supports multipoint connections.
 
+Output groups are `module-combine-sink` instances owned by the running audio
+server. Audio Switcher rediscovers its groups after the plugin service restarts,
+but they disappear if PipeWire/PulseAudio restarts. Combining outputs may add
+latency and resampling CPU cost, especially when the devices use different
+clocks or sample rates.
+
 The plugin does not access the network. Its service spawns only the declared
 `pactl`, `bluetoothctl`, and `sleep` commands. The short sleep is used while
 waiting for a newly connected Bluetooth endpoint to appear. The panel may also

audio-switcher/panel.luau

@@ -31,6 +31,8 @@ local editSlot = ""
 local feedback = ""
 local feedbackError = false
 local requestCounter = 0
+local groupingOutputs = false
+local selectedGroupOutputs = {}
 -- Slider onChange is also emitted when the host applies a new controlled value.
 -- Keep the last callback value only for onDragEnd; rendering from it would turn
 -- the first external update into a sticky local draft and freeze later updates.
@@ -89,6 +91,14 @@ local function hiddenCount(kind)
   return count
 end
 
+local function selectedGroupCount()
+  local count = 0
+  for _, selected in pairs(selectedGroupOutputs) do
+    if selected then count += 1 end
+  end
+  return count
+end
+
 local function selectedIndex(values, selected)
   for index, value in ipairs(values) do
     if value == selected then return index - 1 end
@@ -211,12 +221,56 @@ local function deviceRow(device, kind)
   local hideAction = function()
     sendCommand("set_hidden", { id = device.id, kind = kind, hidden = not device.hidden })
   end
+  local selectAction = function()
+    selectedGroupOutputs[device.id] = not selectedGroupOutputs[device.id]
+    render()
+  end
+  local disbandAction = function()
+    sendCommand("remove_output_group", { id = device.id })
+  end
   local actionText = device.active and tr("device.current")
     or (device.bluetooth and not device.available and tr("actions.connect_and_use") or tr("actions.use"))
   local actionVariant = device.active and "ghost" or "primary"
   local statusColor = device.active and "secondary" or "on_surface_variant"
-  local row = ui.column({ gap = 6 }, {
-    ui.row({ align = "center", gap = 8, padding = 7, radius = 9, border = device.active and "primary" or "outline/0.55", borderWidth = 1, fill = device.active and "primary/0.07" or "surface/0" }, {
+  local actions = {}
+  if groupingOutputs and kind == "output" then
+    table.insert(actions, ui.button({
+      text = selectedGroupOutputs[device.id] and tr("actions.selected") or tr("actions.select"),
+      glyph = selectedGroupOutputs[device.id] and "check" or "plus",
+      variant = selectedGroupOutputs[device.id] and "primary" or "outline",
+      controlSize = "sm",
+      enabled = device.available == true and device.group ~= true and snapshot.busy ~= true,
+      onClick = selectAction,
+    }))
+  else
+    table.insert(actions, ui.button({
+      text = actionText,
+      variant = actionVariant,
+      controlSize = "sm",
+      enabled = not device.active and snapshot.busy ~= true,
+      onClick = useAction,
+    }))
+    if kind == "output" and device.group then
+      table.insert(actions, ui.button({
+        text = tr("actions.disband"),
+        glyph = "unlink",
+        variant = "outline",
+        controlSize = "sm",
+        enabled = snapshot.busy ~= true,
+        onClick = disbandAction,
+      }))
+    else
+      table.insert(actions, ui.button({ glyph = "edit", variant = "ghost", controlSize = "sm", tooltip = tr("actions.edit"), onClick = editAction }))
+      table.insert(actions, ui.button({
+        glyph = device.hidden and "eye" or "eye-off",
+        variant = "ghost",
+        controlSize = "sm",
+        tooltip = tr(device.hidden and "actions.show" or "actions.hide"),
+        onClick = hideAction,
+      }))
+    end
+  end
+  local rowChildren = {
       ui.glyph({ name = device.icon or (kind == "output" and "volume" or "microphone"), size = 19, color = device.active and "primary" or "on_surface_variant" }),
       ui.column({ flexGrow = 1, gap = 2 }, {
         ui.label({ text = tostring(device.name or device.description or device.id), fontWeight = "bold", maxLines = 1 }),
@@ -234,28 +288,48 @@ local function deviceRow(device, kind)
         fontWeight = "bold",
         visible = device.bluetooth == true,
       }),
-      ui.button({
-        text = actionText,
-        variant = actionVariant,
-        controlSize = "sm",
-        enabled = not device.active and snapshot.busy ~= true,
-        onClick = useAction,
-      }),
-      ui.button({ glyph = "edit", variant = "ghost", controlSize = "sm", tooltip = tr("actions.edit"), onClick = editAction }),
-      ui.button({
-        glyph = device.hidden and "eye" or "eye-off",
-        variant = "ghost",
-        controlSize = "sm",
-        tooltip = tr(device.hidden and "actions.show" or "actions.hide"),
-        onClick = hideAction,
-      }),
-    }),
+  }
+  for _, action in ipairs(actions) do table.insert(rowChildren, action) end
+  local row = ui.column({ gap = 6 }, {
+    ui.row({ align = "center", gap = 8, padding = 7, radius = 9, border = selectedGroupOutputs[device.id] and "primary" or (device.active and "primary" or "outline/0.55"), borderWidth = 1, fill = selectedGroupOutputs[device.id] and "primary/0.1" or (device.active and "primary/0.07" or "surface/0") }, rowChildren),
   })
   local children = { row }
   if editingId == device.id then table.insert(children, editor(device)) end
   return ui.column({ gap = 6 }, children)
 end
 
+local function groupingToolbar()
+  if activeTab ~= "output" then return ui.column({ visible = false }, {}) end
+  if not groupingOutputs then
+    return ui.row({ justify = "end" }, {
+      ui.button({
+        text = tr("actions.group_outputs"),
+        glyph = "link",
+        variant = "outline",
+        enabled = snapshot.busy ~= true,
+        onClick = "onStartGrouping",
+      }),
+    })
+  end
+  local count = selectedGroupCount()
+  return ui.row({ align = "center", gap = 8, padding = 8, radius = 9, fill = "primary/0.08" }, {
+    ui.label({
+      text = tr("panel.group_hint", { count = count }),
+      flexGrow = 1,
+      color = "on_surface_variant",
+      fontSize = 11,
+    }),
+    ui.button({ text = tr("actions.cancel"), variant = "ghost", onClick = "onCancelGrouping" }),
+    ui.button({
+      text = tr("actions.create_group", { count = count }),
+      glyph = "link",
+      variant = "primary",
+      enabled = count >= 2 and snapshot.busy ~= true,
+      onClick = "onCreateGroup",
+    }),
+  })
+end
+
 local function deviceList(kind)
   local source = kind == "output" and asArray(snapshot.outputs) or asArray(snapshot.inputs)
   local rows = {}
@@ -357,6 +431,7 @@ render = function()
     header(),
     ui.row({ gap = 12, align = "stretch" }, { volumeCard("output"), volumeCard("input") }),
     toolbar(),
+    groupingToolbar(),
     ui.column({ gap = 3 }, statusRows),
     ui.scroll({ flexGrow = 1, gap = 6 }, { deviceList(activeTab) }),
     ui.label({
@@ -371,6 +446,8 @@ end
 function onOpen(_context)
   feedback = ""
   feedbackError = false
+  groupingOutputs = false
+  selectedGroupOutputs = {}
   sendCommand("refresh")
   render()
 end
@@ -406,9 +483,35 @@ function onShowInputs()
   activeTab = "input"
   editingId = nil
   showHidden = false
+  groupingOutputs = false
+  selectedGroupOutputs = {}
   render()
 end
 
+function onStartGrouping()
+  groupingOutputs = true
+  selectedGroupOutputs = {}
+  editingId = nil
+  showHidden = false
+  feedback = ""
+  render()
+end
+
+function onCancelGrouping()
+  groupingOutputs = false
+  selectedGroupOutputs = {}
+  render()
+end
+
+function onCreateGroup()
+  local ids = {}
+  for _, device in ipairs(asArray(snapshot.outputs)) do
+    if selectedGroupOutputs[device.id] then table.insert(ids, device.id) end
+  end
+  if #ids < 2 then return end
+  sendCommand("create_output_group", { ids = ids })
+end
+
 function onToggleHidden()
   showHidden = not showHidden
   editingId = nil
@@ -478,6 +581,10 @@ noctalia.state.watch(RESULT_KEY, function(result)
   if type(result) ~= "table" or not tostring(result.requestId or ""):match("^panel%-") then return end
   feedback = tostring(result.message or "")
   feedbackError = result.ok ~= true
+  if result.ok == true and result.action == "create_output_group" then
+    groupingOutputs = false
+    selectedGroupOutputs = {}
+  end
   if result.ok ~= true and (result.action == "set_output_volume" or result.action == "set_input_volume") then
     outputVolumeCommitValue = nil
     inputVolumeCommitValue = nil

audio-switcher/plugin.toml

@@ -1,6 +1,6 @@
 id = "blackbartblues/audio-switcher"
 name = "Audio Switcher"
-version = "0.2.2"
+version = "0.3.0"
 plugin_api = 9
 author = "blackbartblues"
 license = "MIT"

audio-switcher/service.luau

@@ -10,6 +10,8 @@ local PREFERENCES_VERSION = 1
 local REFRESH_INTERVAL_MS = 3000
 local BLUETOOTH_CONNECT_RETRIES = 16
 local BLUETOOTH_CONNECT_RETRY_SECONDS = 0.25
+local GROUP_SINK_PREFIX = "noctalia_group_"
+local GROUP_DESCRIPTION = "Noctalia_Output_Group"
 
 local dataDir = noctalia.pluginDataDir()
 local preferencesPath = dataDir and (dataDir .. "/preferences.json") or nil
@@ -58,6 +60,8 @@ local volumeRefreshes = {
   input = { running = false, again = false },
 }
 local audioEventRevisions = { output = 0, input = 0 }
+local combineSinkOption = "slaves"
+local groupNameCounter = 0
 
 local refreshAll
 local setOutput
@@ -236,13 +240,14 @@ local function bluetoothAddress(properties)
   return value:upper()
 end
 
-local function makeOutput(item, defaultName)
+local function makeOutput(item, defaultName, group)
   local properties = propertiesOf(item)
   local address = bluetoothAddress(properties)
   local isBluetooth = address ~= ""
   local stableId = isBluetooth and bluetoothOutputId(address) or tostring(item.name or "")
   local fallback = tostring(properties["device.alias"] or item.description or item.name or stableId)
-  local icon, iconStyle = resolvedDeviceIcon(stableId, isBluetooth and "headphones" or "device-speaker")
+  if group ~= nil then fallback = noctalia.tr("device.output_group") end
+  local icon, iconStyle = resolvedDeviceIcon(stableId, group ~= nil and "link" or (isBluetooth and "headphones" or "device-speaker"))
   return {
     id = stableId,
     targetName = tostring(item.name or ""),
@@ -258,6 +263,9 @@ local function makeOutput(item, defaultName)
     muted = item.mute == true,
     icon = icon,
     iconStyle = iconStyle,
+    group = group ~= nil,
+    groupModuleId = group and group.moduleId or nil,
+    groupMembers = group and group.members or nil,
   }
 end
 
@@ -304,16 +312,42 @@ local function parseInfo(output)
   return {
     defaultSink = tostring(decoded.default_sink_name or ""),
     defaultSource = tostring(decoded.default_source_name or ""),
+    serverName = tostring(decoded.server_name or ""),
   }
 end
 
-local function parseOutputs(output, defaultName)
+local function moduleArgumentValue(argument, key)
+  return tostring(argument or ""):match("%f[%w_]" .. key .. "=([^%s]+)")
+end
+
+local function parseOutputGroups(output)
+  local groups = {}
+  for line in (tostring(output or "") .. "\n"):gmatch("(.-)\n") do
+    local moduleId, moduleName, argument = line:match("^(%d+)%s+([^%s]+)%s+(.-)%s*$")
+    if moduleName == "module-combine-sink" then
+      local sinkName = moduleArgumentValue(argument, "sink_name")
+      local membersValue = moduleArgumentValue(argument, "sinks")
+        or moduleArgumentValue(argument, "slaves")
+      if sinkName ~= nil and sinkName:sub(1, #GROUP_SINK_PREFIX) == GROUP_SINK_PREFIX then
+        local members = {}
+        for member in tostring(membersValue or ""):gmatch("[^,]+") do
+          table.insert(members, member)
+        end
+        groups[sinkName] = { moduleId = tonumber(moduleId), members = members }
+      end
+    end
+  end
+  return groups
+end
+
+local function parseOutputs(output, defaultName, groups)
   local decoded = decodeJson(output)
   local devices = {}
   if decoded == nil then return devices end
   for _, item in ipairs(decoded) do
     if type(item) == "table" and trim(item.name) ~= "" then
-      table.insert(devices, makeOutput(item, defaultName))
+      local name = tostring(item.name or "")
+      table.insert(devices, makeOutput(item, defaultName, groups and groups[name] or nil))
     end
   end
   sortDevices(devices)
@@ -586,59 +620,67 @@ local function loadAudio(callback)
       callback(false, noctalia.tr("errors.invalid_audio_data"))
       return
     end
-    runPactl({ "-f", "json", "list", "sinks" }, function(sinkResult)
-      if sinkResult.exitCode ~= 0 then
-        callback(false, trim(sinkResult.stderr))
+    combineSinkOption = info.serverName:find("PipeWire", 1, true) ~= nil and "sinks" or "slaves"
+    runPactl({ "list", "short", "modules" }, function(moduleResult)
+      if moduleResult.exitCode ~= 0 then
+        callback(false, trim(moduleResult.stderr))
         return
       end
-      runPactl({ "-f", "json", "list", "sources" }, function(sourceResult)
-        if sourceResult.exitCode ~= 0 then
-          callback(false, trim(sourceResult.stderr))
+      local groups = parseOutputGroups(moduleResult.stdout)
+      runPactl({ "-f", "json", "list", "sinks" }, function(sinkResult)
+        if sinkResult.exitCode ~= 0 then
+          callback(false, trim(sinkResult.stderr))
           return
         end
-        local currentOutputVolume = snapshot.outputVolume
-        local currentInputVolume = snapshot.inputVolume
-        local currentOutputMuted = snapshot.outputMuted
-        local currentInputMuted = snapshot.inputMuted
-        snapshot.outputs = parseOutputs(sinkResult.stdout, info.defaultSink)
-        snapshot.inputs = parseInputs(sourceResult.stdout, info.defaultSource)
-        snapshot.defaultOutputId = ""
-        snapshot.defaultInputId = ""
-        snapshot.outputVolume = 0
-        snapshot.inputVolume = 0
-        snapshot.outputMuted = false
-        snapshot.inputMuted = false
-        for _, output in ipairs(snapshot.outputs) do
-          if output.active then
-            snapshot.defaultOutputId = output.id
-            snapshot.outputVolume = output.volume
-            snapshot.outputMuted = output.muted
-            break
+        runPactl({ "-f", "json", "list", "sources" }, function(sourceResult)
+          if sourceResult.exitCode ~= 0 then
+            callback(false, trim(sourceResult.stderr))
+            return
           end
-        end
-        for _, input in ipairs(snapshot.inputs) do
-          if input.active then
-            snapshot.defaultInputId = input.id
-            snapshot.inputVolume = input.volume
-            snapshot.inputMuted = input.muted
-            break
+          local currentOutputVolume = snapshot.outputVolume
+          local currentInputVolume = snapshot.inputVolume
+          local currentOutputMuted = snapshot.outputMuted
+          local currentInputMuted = snapshot.inputMuted
+          snapshot.outputs = parseOutputs(sinkResult.stdout, info.defaultSink, groups)
+          snapshot.inputs = parseInputs(sourceResult.stdout, info.defaultSource)
+          snapshot.defaultOutputId = ""
+          snapshot.defaultInputId = ""
+          snapshot.outputVolume = 0
+          snapshot.inputVolume = 0
+          snapshot.outputMuted = false
+          snapshot.inputMuted = false
+          for _, output in ipairs(snapshot.outputs) do
+            if output.active then
+              snapshot.defaultOutputId = output.id
+              snapshot.outputVolume = output.volume
+              snapshot.outputMuted = output.muted
+              break
+            end
           end
-        end
-        if audioEventRevisions.output ~= outputEventRevision then
-          snapshot.outputVolume = currentOutputVolume
-          snapshot.outputMuted = currentOutputMuted
-        else
-          snapshot.outputVolume = reconcileVolumeDisplay("output", snapshot.outputVolume)
-        end
-        if audioEventRevisions.input ~= inputEventRevision then
-          snapshot.inputVolume = currentInputVolume
-          snapshot.inputMuted = currentInputMuted
-        else
-          snapshot.inputVolume = reconcileVolumeDisplay("input", snapshot.inputVolume)
-        end
-        updateActiveDeviceVolume("output", snapshot.outputVolume, snapshot.outputMuted)
-        updateActiveDeviceVolume("input", snapshot.inputVolume, snapshot.inputMuted)
-        callback(true, "")
+          for _, input in ipairs(snapshot.inputs) do
+            if input.active then
+              snapshot.defaultInputId = input.id
+              snapshot.inputVolume = input.volume
+              snapshot.inputMuted = input.muted
+              break
+            end
+          end
+          if audioEventRevisions.output ~= outputEventRevision then
+            snapshot.outputVolume = currentOutputVolume
+            snapshot.outputMuted = currentOutputMuted
+          else
+            snapshot.outputVolume = reconcileVolumeDisplay("output", snapshot.outputVolume)
+          end
+          if audioEventRevisions.input ~= inputEventRevision then
+            snapshot.inputVolume = currentInputVolume
+            snapshot.inputMuted = currentInputMuted
+          else
+            snapshot.inputVolume = reconcileVolumeDisplay("input", snapshot.inputVolume)
+          end
+          updateActiveDeviceVolume("output", snapshot.outputVolume, snapshot.outputMuted)
+          updateActiveDeviceVolume("input", snapshot.inputVolume, snapshot.inputMuted)
+          callback(true, "")
+        end)
       end)
     end)
   end)
@@ -774,6 +816,119 @@ local function setDefaultTarget(command, kind, device)
   end)
 end
 
+local function uniqueGroupSinkName()
+  groupNameCounter += 1
+  local base = GROUP_SINK_PREFIX .. tostring(os.time()) .. "_" .. tostring(groupNameCounter)
+  local candidate = base
+  local suffix = 1
+  while findOutputById(candidate) ~= nil do
+    suffix += 1
+    candidate = base .. "_" .. tostring(suffix)
+  end
+  return candidate
+end
+
+local function createOutputGroup(command)
+  if actionBusy then
+    resultMessage(command, false, noctalia.tr("errors.busy"))
+    return
+  end
+  local selected = {}
+  local seen = {}
+  for _, id in ipairs(type(command.ids) == "table" and command.ids or {}) do
+    local device = findOutputById(tostring(id or ""))
+    if device ~= nil and device.available and not device.group and trim(device.targetName) ~= "" and not seen[device.id] then
+      seen[device.id] = true
+      table.insert(selected, device)
+    end
+  end
+  if #selected < 2 then
+    resultMessage(command, false, noctalia.tr("errors.group_requires_two"))
+    return
+  end
+
+  local targetNames = {}
+  for _, device in ipairs(selected) do table.insert(targetNames, device.targetName) end
+  local sinkName = uniqueGroupSinkName()
+  actionBusy = true
+  publishSnapshot()
+  runPactl({
+    "load-module",
+    "module-combine-sink",
+    "sink_name=" .. sinkName,
+    combineSinkOption .. "=" .. table.concat(targetNames, ","),
+    "sink_properties=device.description=" .. GROUP_DESCRIPTION,
+  }, function(loadResult)
+    local moduleId = tonumber(trim(loadResult.stdout))
+    if loadResult.exitCode ~= 0 or moduleId == nil then
+      local message = trim(loadResult.stderr)
+      finishAction(command, false, message ~= "" and message or noctalia.tr("errors.group_create_failed"))
+      return
+    end
+    runPactl({ "set-default-sink", sinkName }, function(defaultResult)
+      if defaultResult.exitCode ~= 0 then
+        runPactl({ "unload-module", tostring(moduleId) }, function()
+          local message = trim(defaultResult.stderr)
+          finishAction(command, false, message ~= "" and message or noctalia.tr("errors.group_switch_failed"))
+        end)
+        return
+      end
+      moveStreams("output", sinkName, function()
+        finishAction(command, true, noctalia.tr("notifications.group_created"))
+      end)
+    end)
+  end)
+end
+
+local function removeOutputGroup(command)
+  if actionBusy then
+    resultMessage(command, false, noctalia.tr("errors.busy"))
+    return
+  end
+  local group = findOutputById(tostring(command.id or ""))
+  if group == nil or not group.group or tonumber(group.groupModuleId) == nil then
+    resultMessage(command, false, noctalia.tr("errors.group_not_found"))
+    return
+  end
+
+  local fallback = nil
+  for _, targetName in ipairs(type(group.groupMembers) == "table" and group.groupMembers or {}) do
+    for _, device in ipairs(snapshot.outputs) do
+      if not device.group and device.available and device.targetName == targetName then
+        fallback = device
+        break
+      end
+    end
+    if fallback ~= nil then break end
+  end
+
+  actionBusy = true
+  publishSnapshot()
+  local function unloadGroup()
+    runPactl({ "unload-module", tostring(group.groupModuleId) }, function(result)
+      if result.exitCode ~= 0 then
+        local message = trim(result.stderr)
+        finishAction(command, false, message ~= "" and message or noctalia.tr("errors.group_remove_failed"))
+        return
+      end
+      finishAction(command, true, noctalia.tr("notifications.group_removed"))
+    end)
+  end
+
+  if group.active and fallback ~= nil then
+    runPactl({ "set-default-sink", fallback.targetName }, function(result)
+      if result.exitCode ~= 0 then
+        local message = trim(result.stderr)
+        finishAction(command, false, message ~= "" and message or noctalia.tr("errors.group_switch_failed"))
+        return
+      end
+      moveStreams("output", fallback.targetName, unloadGroup)
+    end)
+  else
+    unloadGroup()
+  end
+end
+
 assignSlot = function(address)
   address = tostring(address or ""):upper()
   if address == "" or tonumber(preferences.slots[address]) ~= nil then return end
@@ -1111,6 +1266,10 @@ local function executeCommand(command)
     setOutput(command, tostring(command.id or ""))
   elseif action == "set_input" then
     setInput(command, tostring(command.id or ""))
+  elseif action == "create_output_group" then
+    createOutputGroup(command)
+  elseif action == "remove_output_group" then
+    removeOutputGroup(command)
   elseif action == "cycle_output" then
     cycleDevice(command, "output")
   elseif action == "cycle_input" then

audio-switcher/tests/mute_state_test.lua

@@ -14,6 +14,7 @@ local decoded = {
   INFO = {
     default_sink_name = "sink.main",
     default_source_name = "source.main",
+    server_name = "PulseAudio (on PipeWire 1.6.8)",
   },
   SINKS_UNMUTED = {
     {
@@ -106,6 +107,7 @@ assert(load(serviceSource, "@service.luau"))()
 assert(type(streamCallback) == "function", "pactl subscription was not started")
 
 complete("'info'", "INFO")
+complete("'list' 'short' 'modules'", "")
 complete("'list' 'sinks'", "SINKS_UNMUTED")
 complete("'list' 'sources'", "SOURCES_UNMUTED")
 

audio-switcher/tests/output_group_test.lua

@@ -0,0 +1,200 @@
+local function clone(value)
+  if type(value) ~= "table" then return value end
+  local result = {}
+  for key, item in pairs(value) do result[clone(key)] = clone(item) end
+  return result
+end
+
+local values = {}
+local watchers = {}
+local pending = {}
+
+local decoded = {
+  INFO_PHYSICAL = {
+    default_sink_name = "sink.a",
+    default_source_name = "source.main",
+    server_name = "PulseAudio (on PipeWire 1.6.8)",
+  },
+  INFO_GROUPED = {
+    default_sink_name = "noctalia_group_123_1",
+    default_source_name = "source.main",
+    server_name = "PulseAudio (on PipeWire 1.6.8)",
+  },
+  SINKS_PHYSICAL = {
+    {
+      name = "sink.a",
+      description = "Speakers",
+      mute = false,
+      volume = { front_left = { value_percent = "40%" } },
+      properties = {},
+    },
+    {
+      name = "sink.b",
+      description = "Headphones",
+      mute = false,
+      volume = { front_left = { value_percent = "40%" } },
+      properties = {},
+    },
+  },
+  SINKS_GROUPED = {
+    {
+      name = "sink.a",
+      description = "Speakers",
+      mute = false,
+      volume = { front_left = { value_percent = "40%" } },
+      properties = {},
+    },
+    {
+      name = "sink.b",
+      description = "Headphones",
+      mute = false,
+      volume = { front_left = { value_percent = "40%" } },
+      properties = {},
+    },
+    {
+      name = "noctalia_group_123_1",
+      description = "Noctalia Output Group",
+      mute = false,
+      volume = { front_left = { value_percent = "40%" } },
+      properties = {},
+    },
+  },
+  SOURCES = {
+    {
+      name = "source.main",
+      description = "Microphone",
+      mute = false,
+      volume = { front_left = { value_percent = "30%" } },
+      properties = {},
+    },
+  },
+  STREAMS_EMPTY = {},
+}
+
+local fakeTime = 123
+
+noctalia = {
+  pluginDataDir = function() return nil end,
+  getConfig = function() return nil end,
+  commandExists = function(command) return command == "pactl" end,
+  readFile = function() return nil end,
+  writeFile = function() return true end,
+  setUpdateInterval = function() end,
+  runAsync = function(command, callback)
+    pending[#pending + 1] = { command = command, callback = callback }
+    return true
+  end,
+  runStream = function() return true end,
+  json = {
+    decode = function(value) return clone(decoded[value]) end,
+    encode = function() return "PREFERENCES" end,
+  },
+  string = {
+    trim = function(value) return tostring(value or ""):match("^%s*(.-)%s*$") or "" end,
+  },
+  state = {
+    get = function(key) return clone(values[key]) end,
+    set = function(key, value)
+      values[key] = clone(value)
+      if watchers[key] ~= nil then watchers[key](clone(value)) end
+    end,
+    watch = function(key, callback) watchers[key] = callback end,
+  },
+  tr = function(key) return key end,
+  log = function() end,
+  notify = function() end,
+  notifyError = function() end,
+}
+
+local function complete(expected, stdout, exitCode)
+  local call = table.remove(pending, 1)
+  assert(call ~= nil, "expected pending command containing " .. expected)
+  assert(call.command:find(expected, 1, true) ~= nil, "unexpected command: " .. call.command)
+  call.callback({
+    exitCode = exitCode or 0,
+    stdout = stdout or "",
+    stderr = "",
+    timedOut = false,
+    stdoutTruncated = false,
+    stderrTruncated = false,
+  })
+end
+
+local function completeRefresh(info, modules, sinks)
+  complete("'info'", info)
+  complete("'list' 'short' 'modules'", modules)
+  complete("'list' 'sinks'", sinks)
+  complete("'list' 'sources'", "SOURCES")
+end
+
+local originalTime = os.time
+os.time = function() return fakeTime end
+
+local serviceFile = assert(io.open("service.luau", "r"))
+local serviceSource = serviceFile:read("*a")
+serviceFile:close()
+serviceSource = serviceSource:gsub("([%w_%.]+)%s*%+=%s*([^\n]+)", "%1 = %1 + %2")
+serviceSource = serviceSource:gsub("([%w_%.]+)%s*%-=%s*([^\n]+)", "%1 = %1 - %2")
+assert(load(serviceSource, "@service.luau"))()
+
+completeRefresh("INFO_PHYSICAL", "", "SINKS_PHYSICAL")
+
+noctalia.state.set("audio_switcher_command", {
+  requestId = "create-group",
+  action = "create_output_group",
+  ids = { "sink.a", "sink.b" },
+})
+assert(pending[1].command:find("'sinks=sink.a,sink.b'", 1, true), "PipeWire must use the sinks module option")
+complete("'load-module' 'module-combine-sink'", "77\n")
+complete("'set-default-sink' 'noctalia_group_123_1'")
+complete("'list' 'sink-inputs'", "STREAMS_EMPTY")
+completeRefresh(
+  "INFO_GROUPED",
+  "77\tmodule-combine-sink\tsink_name=noctalia_group_123_1 sinks=sink.a,sink.b sink_properties=device.description=Noctalia_Output_Group\t\n",
+  "SINKS_GROUPED"
+)
+
+local snapshot = values["audio_switcher_snapshot"]
+local group = nil
+for _, output in ipairs(snapshot.outputs) do
+  if output.group then group = output end
+end
+assert(group ~= nil, "plugin-created combine sink was not detected")
+assert(group.active == true, "new output group is not active")
+assert(group.groupModuleId == 77, "module index was not retained")
+assert(#group.groupMembers == 2, "group members were not parsed")
+
+noctalia.state.set("audio_switcher_command", {
+  requestId = "remove-group",
+  action = "remove_output_group",
+  id = group.id,
+})
+complete("'set-default-sink' 'sink.a'")
+complete("'list' 'sink-inputs'", "STREAMS_EMPTY")
+complete("'unload-module' '77'")
+completeRefresh("INFO_PHYSICAL", "", "SINKS_PHYSICAL")
+
+snapshot = values["audio_switcher_snapshot"]
+for _, output in ipairs(snapshot.outputs) do
+  assert(output.group ~= true, "removed group remained in the snapshot")
+end
+
+decoded.INFO_PHYSICAL.server_name = "pulseaudio"
+noctalia.state.set("audio_switcher_command", {
+  requestId = "refresh-pulseaudio",
+  action = "refresh",
+})
+completeRefresh("INFO_PHYSICAL", "", "SINKS_PHYSICAL")
+noctalia.state.set("audio_switcher_command", {
+  requestId = "create-pulseaudio-group",
+  action = "create_output_group",
+  ids = { "sink.a", "sink.b" },
+})
+assert(pending[1].command:find("'slaves=sink.a,sink.b'", 1, true), "PulseAudio must use the slaves module option")
+complete("'load-module' 'module-combine-sink'", "", 1)
+completeRefresh("INFO_PHYSICAL", "", "SINKS_PHYSICAL")
+
+assert(#pending == 0, "unexpected commands remain pending")
+
+os.time = originalTime
+print("audio-switcher output group tests: ok")

audio-switcher/translations/en.json

@@ -3,11 +3,16 @@
     "cancel": "Cancel",
     "close": "Close",
     "connect_and_use": "Connect & use",
+    "create_group": "Create group ({count})",
     "cycle": "Cycle",
+    "disband": "Disband",
     "edit": "Edit device",
+    "group_outputs": "Group outputs",
     "hide": "Hide device",
     "refresh": "Refresh",
     "save": "Save",
+    "select": "Select",
+    "selected": "Selected",
     "settings": "Plugin settings",
     "show": "Show device",
     "use": "Use"
@@ -17,7 +22,8 @@
     "available": "Available",
     "bluetooth_connected": "Bluetooth connected",
     "bluetooth_disconnected": "Bluetooth disconnected",
-    "current": "Current"
+    "current": "Current",
+    "output_group": "Output group"
   },
   "editor": {
     "alias": "Display name",
@@ -43,6 +49,11 @@
     "command_start": "Could not start the system command.",
     "device_not_found": "The selected device no longer exists.",
     "device_unavailable": "The selected device is not currently available.",
+    "group_create_failed": "Could not create the output group.",
+    "group_not_found": "The output group no longer exists.",
+    "group_remove_failed": "Could not disband the output group.",
+    "group_requires_two": "Select at least two available outputs.",
+    "group_switch_failed": "The output group was created, but could not be selected.",
     "invalid_audio_data": "The audio service returned invalid data.",
     "invalid_slot": "The keybind number must be a whole number from 1 to 99.",
     "invalid_volume": "The requested volume is invalid.",
@@ -55,6 +66,8 @@
   },
   "notifications": {
     "bluetooth_disconnected": "Bluetooth device disconnected.",
+    "group_created": "Output group created and selected.",
+    "group_removed": "Output group disbanded.",
     "input_selected": "Input switched to {device}.",
     "output_selected": "Output switched to {device}.",
     "preferences_saved": "Device preferences saved.",
@@ -62,6 +75,7 @@
     "slot_saved": "Keybind number {slot} saved."
   },
   "panel": {
+    "group_hint": "{count} selected. Choose at least two available outputs.",
     "hidden": "Hidden",
     "hidden_count": "Hidden {count}",
     "input_volume": "Microphone",