From 423709dd2302a2a89fc1cf5b55b8c6e76445c945 Mon Sep 17 00:00:00 2001
From: Bram Kragten <mail@bramkragten.nl>
Date: Mon, 3 Apr 2023 20:37:49 +0200
Subject: [PATCH] Add deprecation warning Polymer (#16044)

---
 src/util/legacy-support.js | 25 ++++++++++++++++++++++++-
 1 file changed, 24 insertions(+), 1 deletion(-)

diff --git a/src/util/legacy-support.js b/src/util/legacy-support.js
index ab77431315..c94ffffdb0 100644
--- a/src/util/legacy-support.js
+++ b/src/util/legacy-support.js
@@ -7,6 +7,29 @@ import { html } from "@polymer/polymer/lib/utils/html-tag";
 import { PolymerElement } from "@polymer/polymer/polymer-element";
 import { Polymer } from "@polymer/polymer/polymer-legacy";
 
+const message =
+  "WARNING: Polymer will be removed from window in Home Assistant 2023.5. More info: https://developers.home-assistant.io/blog/2023/04/04/deprecating_polymer";
+
+const handler = {
+  get(target, prop, receiver) {
+    // eslint-disable-next-line no-console
+    console.warn(message);
+    document
+      .querySelector("home-assistant")
+      .dispatchEvent(new CustomEvent("write_log", { detail: { message } }));
+    return Reflect.get(target, prop, receiver);
+  },
+  apply: function (target, thisArg, argumentsList) {
+    // eslint-disable-next-line no-console
+    console.warn(message);
+    document
+      .querySelector("home-assistant")
+      .dispatchEvent(new CustomEvent("write_log", { detail: { message } }));
+    return Reflect.apply(target, thisArg, argumentsList);
+  },
+};
+
 Polymer.Element = PolymerElement;
 Polymer.html = html;
-window.Polymer = Polymer;
+
+window.Polymer = new Proxy(Polymer, handler);