4 files changed, 77 insertions, 0 deletions
diff --git a/src/lib/motion/index.ts b/src/lib/motion/index.ts
new file mode 100644
index 0000000..79e3d36
--- /dev/null
+++ b/src/lib/motion/index.ts
@@ -0,0 +1,4 @@
+import { signal } from './signal'
+import { animate, all } from './utils'
+
+export { signal, animate, all }
diff --git a/src/lib/motion/signal.ts b/src/lib/motion/signal.ts
new file mode 100644
index 0000000..99697ce
--- /dev/null
+++ b/src/lib/motion/signal.ts
@@ -0,0 +1,61 @@
+import { tweened, type TweenedOptions } from 'svelte/motion'
+import { cubicInOut } from 'svelte/easing'
+import { interpolate } from 'd3-interpolate'
+import type { AnimationFn, Resolve } from './types'
+
+export function signal<TweenValues>(
+	values: TweenValues,
+	options: TweenedOptions<TweenValues> = {}
+) {
+	const { subscribe, update, set } = tweened<TweenValues>(values, {
+		duration: 1000,
+		easing: cubicInOut,
+		interpolate,
+		...options,
+	})
+
+	let tasks: AnimationFn[] = []
+
+	function to(
+		this: any,
+		values: Partial<TweenValues>,
+		toOptions: TweenedOptions<TweenValues> = {}
+	) {
+		if (typeof values === 'object') {
+			tasks.push(() => update((prev) => ({ ...prev, ...values }), toOptions))
+		} else {
+			tasks.push(() => set(values, toOptions))
+		}
+		return this
+	}
+
+	function reset() {
+		set(values, { duration: 0 })
+		tasks = []
+	}
+
+	function sfx(this: any, sound: string, { volume = 0.5 } = {}) {
+		const audio = new Audio(sound)
+		audio.volume = volume
+
+		tasks.push(async () => {
+			audio
+				.play()
+				.catch(() =>
+					console.error('To play sounds interact with the page first.')
+				)
+		})
+
+		return this
+	}
+
+	async function then(resolve: Resolve) {
+		for (const task of tasks) {
+			await task()
+		}
+		resolve()
+		tasks = []
+	}
+
+	return { subscribe, to, reset, sfx, then }
+}
diff --git a/src/lib/motion/types.ts b/src/lib/motion/types.ts
new file mode 100644
index 0000000..e97a109
--- /dev/null
+++ b/src/lib/motion/types.ts
@@ -0,0 +1,2 @@
+export type AnimationFn = () => Promise<void>
+export type Resolve = (value?: any) => Promise<void>
diff --git a/src/lib/motion/utils.ts b/src/lib/motion/utils.ts
new file mode 100644
index 0000000..a81c02e
--- /dev/null
+++ b/src/lib/motion/utils.ts
@@ -0,0 +1,10 @@
+import { onMount } from 'svelte'
+import type { AnimationFn } from './types'
+
+export function animate(fn: AnimationFn) {
+	onMount(fn)
+}
+
+export function all(...animations: AnimationFn[]) {
+	return Promise.all(animations)
+}