Split up spinner and widget API into files

web/widget-api.js

@@ -0,0 +1,47 @@
+// Copyright (c) 2020 Tulir Asokan
+//
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this
+// file, You can obtain one at http://mozilla.org/MPL/2.0/.
+let widgetId = null
+
+window.onmessage = event => {
+	if (!window.parent || !event.data) {
+		return
+	}
+
+	const request = event.data
+	if (!request.requestId || !request.widgetId || !request.action || request.api !== "toWidget") {
+		return
+	}
+
+	if (widgetId) {
+		if (widgetId !== request.widgetId) {
+			return
+		}
+	} else {
+		widgetId = request.widgetId
+	}
+
+	window.parent.postMessage({
+		...request,
+		response: request.action === "capabilities" ? {
+			capabilities: ["m.sticker"],
+		} : {
+			error: { message: "Action not supported" },
+		},
+	}, event.origin)
+}
+
+export function sendSticker(content) {
+	window.parent.postMessage({
+		api: "fromWidget",
+		action: "m.sticker",
+		requestId: `sticker-${Date.now()}`,
+		widgetId,
+		data: {
+			name: content.body,
+			content,
+		},
+	}, "*")
+}