1 files changed, 99 insertions, 0 deletions
diff --git a/apps/web/src/animation/graph-channels.ts b/apps/web/src/animation/graph-channels.ts
new file mode 100644
index 00000000..d6482602
--- /dev/null
+++ b/apps/web/src/animation/graph-channels.ts
@@ -0,0 +1,99 @@
+import type {
+	AnimationBindingInstance,
+	AnimationPath,
+	ElementAnimations,
+	ScalarAnimationChannel,
+	ScalarGraphChannel,
+	ScalarGraphKeyframeContext,
+} from "@/animation/types";
+
+export interface EditableScalarChannels {
+	binding: AnimationBindingInstance;
+	channels: ScalarGraphChannel[];
+}
+
+function isScalarAnimationChannel(
+	channel: ElementAnimations["channels"][string],
+): channel is ScalarAnimationChannel {
+	return channel?.kind === "scalar";
+}
+
+export function getEditableScalarChannels({
+	animations,
+	propertyPath,
+}: {
+	animations: ElementAnimations | undefined;
+	propertyPath: AnimationPath;
+}): EditableScalarChannels | null {
+	const binding = animations?.bindings[propertyPath];
+	if (!binding) {
+		return null;
+	}
+
+	const channels = binding.components.flatMap((component) => {
+		const channel = animations?.channels[component.channelId];
+		if (!isScalarAnimationChannel(channel)) {
+			return [];
+		}
+
+		return [
+			{
+				propertyPath,
+				componentKey: component.key,
+				channelId: component.channelId,
+				channel,
+			} satisfies ScalarGraphChannel,
+		];
+	});
+
+	return { binding, channels };
+}
+
+export function getEditableScalarChannel({
+	animations,
+	propertyPath,
+	componentKey,
+}: {
+	animations: ElementAnimations | undefined;
+	propertyPath: AnimationPath;
+	componentKey: string;
+}): ScalarGraphChannel | null {
+	const result = getEditableScalarChannels({ animations, propertyPath });
+	return result?.channels.find((channel) => channel.componentKey === componentKey) ?? null;
+}
+
+export function getScalarKeyframeContext({
+	animations,
+	propertyPath,
+	componentKey,
+	keyframeId,
+}: {
+	animations: ElementAnimations | undefined;
+	propertyPath: AnimationPath;
+	componentKey: string;
+	keyframeId: string;
+}): ScalarGraphKeyframeContext | null {
+	const scalarChannel = getEditableScalarChannel({
+		animations,
+		propertyPath,
+		componentKey,
+	});
+	if (!scalarChannel) {
+		return null;
+	}
+
+	const keyframeIndex = scalarChannel.channel.keys.findIndex(
+		(keyframe) => keyframe.id === keyframeId,
+	);
+	if (keyframeIndex < 0) {
+		return null;
+	}
+
+	return {
+		...scalarChannel,
+		keyframe: scalarChannel.channel.keys[keyframeIndex],
+		keyframeIndex,
+		previousKey: scalarChannel.channel.keys[keyframeIndex - 1] ?? null,
+		nextKey: scalarChannel.channel.keys[keyframeIndex + 1] ?? null,
+	};
+}