feat: Add broadcast creation, stream binding, and thumbnail actions

Add create broadcast action with title, description, visibility, scheduled
start time, auto-start/stop, monitor stream, thumbnail, and stream binding
options. Add standalone set thumbnail and bind/unbind stream actions.

Add last_created_broadcast_id variable, available streams cache with
listStreams API, and update HELP.md documentation.

Author: makstech

companion/HELP.md

@@ -8,9 +8,7 @@ broadcasts that the action might be performed upon, or by specifying its ID (the
 part after the `?v=...` in a YouTube video URL) as textual input. A checkbox
 switches between the two modes.
 
-The module currently only allows already-created broadcasts to be manipulated:
-it doesn't offer a way to create them itself. You'll have to create a broadcast
-in YouTube Studio in order to be able to manipulate it.
+The module can create new broadcasts and manipulate existing ones.
 
 ## Available actions
 
@@ -47,6 +45,18 @@ in YouTube Studio in order to be able to manipulate it.
   the description.
 - **Add chapter timecode to description** - This action inserts a chapter
   timecode at the end of the description.
+- **Create new broadcast** - This action creates a new YouTube broadcast with
+  the specified settings. Supports using an existing broadcast as a template to
+  copy settings from (title, description, monitor stream, and stream binding).
+  Options include scheduled start time (now, minutes from now, or custom ISO
+  8601), privacy status, auto-start/auto-stop, thumbnail upload, and stream
+  binding.
+- **Set broadcast thumbnail** - This action uploads and sets a custom thumbnail
+  image for a broadcast. Accepts a local file path or URL to a JPEG/PNG image
+  (max 2MB).
+- **Bind stream to broadcast** - This action binds a video stream to a
+  broadcast, which is required before going live. Select a stream from the
+  dropdown or enter a stream ID manually.
 
 [ytapi]: https://developers.google.com/youtube/v3/live/docs/liveBroadcasts/transition
 
@@ -165,6 +175,34 @@ completing the consent process can be found underneath that link.
 Consent while in "Testing" status only lasts a week. After that you'll have to
 reopen the consent screen and recomplete the consent process.
 
+## Available feedbacks
+
+- **Broadcast status** - Changes button colors based on the broadcast lifecycle
+  state (ready, testing, live, complete). Colors are configurable.
+- **Health of stream bound to broadcast** - Changes button colors based on the
+  health of the video stream bound to a broadcast (good, ok, bad, no data).
+
+## Available variables
+
+Per-broadcast variables (where `ID` is the YouTube broadcast ID):
+
+- `broadcast_ID_lifecycle` - Lifecycle state of the broadcast
+- `broadcast_ID_health` - Health of the stream bound to the broadcast
+
+Unfinished broadcast variables (where `N` is the index, starting from 0):
+
+- `unfinished_N` - Name of unfinished broadcast #N
+- `unfinished_N_id` - ID of unfinished broadcast #N
+- `unfinished_short_N` - Shortened name of unfinished broadcast #N
+- `unfinished_state_N` - State of unfinished broadcast #N
+- `unfinished_health_N` - Stream health of unfinished broadcast #N
+- `unfinished_concurrent_viewers_N` - Concurrent viewers of unfinished broadcast #N
+
+Global variables:
+
+- `last_created_broadcast_id` - ID of the most recently created broadcast (via
+  the "Create new broadcast" action)
+
 ## Action configuration
 
 When creating actions to operate upon a broadcast, pick the broadcast to work
@@ -179,6 +217,21 @@ to switch to a text input and enter it there. The text field supports
 variables, so you can also store the broadcast ID in a variable and change that
 variable as needed.
 
+### Using templates with Create broadcast
+
+When creating a broadcast, you can check "Use existing broadcast as template" to
+copy settings from an existing broadcast. Template values serve as defaults:
+any value you explicitly set will override the template. This is useful for
+creating broadcasts with consistent settings. The template's description,
+monitor stream setting, and stream binding will be copied if you don't provide
+your own.
+
+### Using the last created broadcast ID
+
+After creating a broadcast, its ID is stored in the `last_created_broadcast_id`
+variable. You can use this variable in subsequent actions (via text input mode)
+to operate on the newly created broadcast without knowing its ID in advance.
+
 ## Thanks
 
 Big thanks to members of [AVC Silicon Hill](https://avc.sh.cvut.cz/) for

src/__mocks__/@googleapis/youtube.ts

@@ -36,6 +36,18 @@ export function makeMockYT(memory: StateMemory): YoutubeAPI {
 		setVisibility: vi.fn<YoutubeAPI['setVisibility']>().mockImplementation(async () => {
 			return Promise.resolve();
 		}),
+		createBroadcast: vi.fn<YoutubeAPI['createBroadcast']>().mockImplementation(async () => {
+			return Promise.resolve('newBroadcastId');
+		}),
+		setThumbnail: vi.fn<YoutubeAPI['setThumbnail']>().mockImplementation(async () => {
+			return Promise.resolve();
+		}),
+		listStreams: vi.fn<YoutubeAPI['listStreams']>().mockImplementation(async () => {
+			return Promise.resolve(memory.Streams);
+		}),
+		bindBroadcastToStream: vi.fn<YoutubeAPI['bindBroadcastToStream']>().mockImplementation(async () => {
+			return Promise.resolve();
+		}),
 	};
 }
 
@@ -80,6 +92,11 @@ export class FakeYouTube {
 		insertCuepoint:
 			vi.fn<LiveBroadcastsMethod<'insertCuepoint', [youtube_v3.Params$Resource$Livebroadcasts$Insertcuepoint]>>(),
 		update: vi.fn<LiveBroadcastsMethod<'update', [youtube_v3.Params$Resource$Livebroadcasts$Update]>>(),
+		insert: vi.fn(),
+		bind: vi.fn(),
+	};
+	thumbnails = {
+		set: vi.fn(),
 	};
 }
 

src/actions.test.ts

@@ -27,7 +27,9 @@ const SampleMemory: StateMemory = {
 		},
 	},
 	Streams: {},
+	BoundStreams: {},
 	UnfinishedBroadcasts: [],
+	LastCreatedBroadcast: null,
 };
 
 //
@@ -36,7 +38,7 @@ const SampleMemory: StateMemory = {
 
 describe('Action list', () => {
 	test('Module has required actions', () => {
-		const result = listActions({ broadcasts: SampleMemory.Broadcasts, unfinishedCount: 3, core: null });
+		const result = listActions({ broadcasts: SampleMemory.Broadcasts, unfinishedCount: 3, core: null, streams: {} });
 		expect(result).toHaveProperty(ActionId.InitBroadcast);
 		expect(result).toHaveProperty(ActionId.StartBroadcast);
 		expect(result).toHaveProperty(ActionId.StopBroadcast);
@@ -114,8 +116,8 @@ describe('Action callback', () => {
 	void coreKO.init();
 
 	// List actions
-	const actionsOK = listActions({ broadcasts: SampleMemory.Broadcasts, unfinishedCount: 0, core: coreOK });
-	const actionsKO = listActions({ broadcasts: SampleMemory.Broadcasts, unfinishedCount: 0, core: coreKO });
+	const actionsOK = listActions({ broadcasts: SampleMemory.Broadcasts, unfinishedCount: 0, core: coreOK, streams: {} });
+	const actionsKO = listActions({ broadcasts: SampleMemory.Broadcasts, unfinishedCount: 0, core: coreKO, streams: {} });
 
 	// Make event
 	function makeEvent(actionId: string, options: CompanionOptionValues): CompanionActionEvent {