Add Avatar Customisation Commands (#1108)

* Add Avatar Command to bot mode and AS mode

* Add changesets

* Move MXC URI validation to matrix basic types

* Fix MediaID being mixed case when its exempt from usual case rules.

* Update changeset

* Integrate Gnuxie Review Feedback

* Fix linting errors

* Fix having forgotten to run prettier.

* Integrate Gnuxie review feedback.

* Fix version.txt.tmp files

packages/matrix-basic-types/src/StringlyTypedMatrix/StringMediaURI.test.ts

@@ -0,0 +1,38 @@
+// Copyright 2026 Catalan Lover <catalanlover@protonmail.com>
+//
+// SPDX-License-Identifier: Apache-2.0
+
+import {
+  StringMediaURI,
+  isStringMediaURI,
+  MediaURIMediaID,
+  MediaURIServerName,
+} from "./StringMediaURI";
+
+test("isStringMediaURI accepts valid MXC URIs", function () {
+  expect(isStringMediaURI("mxc://matrix.org/abc123")).toBe(true);
+  expect(isStringMediaURI("mxc://matrix.org:8888/abc123")).toBe(true);
+  expect(isStringMediaURI("mxc://1.2.3.4/abc123")).toBe(true);
+  expect(isStringMediaURI("mxc://1.2.3.4:1234/abc123")).toBe(true);
+  expect(isStringMediaURI("mxc://[1234:5678::abcd]/abc123")).toBe(true);
+  expect(isStringMediaURI("mxc://[1234:5678::abcd]:5678/abc123")).toBe(true);
+  expect(isStringMediaURI("mxc://[::1]/abc123")).toBe(true);
+  expect(isStringMediaURI("mxc://[::1]:8008/abc123")).toBe(true);
+  expect(isStringMediaURI("mxc://matrix.org/a_b-c123")).toBe(true);
+});
+
+test("isStringMediaURI rejects invalid MXC URIs", function () {
+  expect(isStringMediaURI("invalid://matrix.org/abc123")).toBe(false);
+  expect(isStringMediaURI("mxc://matrix.org")).toBe(false);
+  expect(isStringMediaURI("mxc://matrix.org/abc 123")).toBe(false);
+  expect(isStringMediaURI("mxc://example.com~invalid/abc123")).toBe(false);
+  expect(isStringMediaURI("mxc://matrix.org/abc.def")).toBe(false);
+  expect(isStringMediaURI("mxc://matrix.org/abc~def")).toBe(false);
+});
+
+test("StringMediaURI accessors", function () {
+  const uri = StringMediaURI("mxc://[1234:5678::abcd]:5678/abc123");
+
+  expect(MediaURIServerName(uri)).toBe("[1234:5678::abcd]:5678");
+  expect(MediaURIMediaID(uri)).toBe("abc123");
+});

packages/matrix-basic-types/src/StringlyTypedMatrix/StringMediaURI.ts

@@ -0,0 +1,49 @@
+// SPDX-FileCopyrightText: 2026 Catalan Lover <catalanlover@protonmail.com>
+//
+// SPDX-License-Identifier: Apache-2.0
+
+import {
+  StringServerName,
+  StringServerNameRegexPart,
+} from "./StringServerName";
+
+export const StringMediaURIRegex = new RegExp(
+  `^mxc://(?<serverName>${StringServerNameRegexPart.source})/(?<mediaID>[A-Za-z0-9_-]+)$`
+);
+
+export type StringMediaURIBrand = {
+  readonly StringMediaURI: unique symbol;
+};
+
+export type StringMediaURI = string & StringMediaURIBrand;
+
+export function isStringMediaURI(string: string): string is StringMediaURI {
+  return StringMediaURIRegex.test(string);
+}
+
+export function StringMediaURI(string: unknown): StringMediaURI {
+  if (typeof string === "string" && isStringMediaURI(string)) {
+    return string;
+  }
+  throw new TypeError("Not a valid StringMediaURI");
+}
+
+export function MediaURIServerName(uri: StringMediaURI): StringServerName {
+  const match = StringMediaURIRegex.exec(uri)?.groups?.serverName;
+  if (match === undefined) {
+    throw new TypeError(
+      "Somehow a StringMediaURI was created that is invalid."
+    );
+  }
+  return match as StringServerName;
+}
+
+export function MediaURIMediaID(uri: StringMediaURI): string {
+  const match = StringMediaURIRegex.exec(uri)?.groups?.mediaID;
+  if (match === undefined) {
+    throw new TypeError(
+      "Somehow a StringMediaURI was created that is invalid."
+    );
+  }
+  return match;
+}

packages/matrix-basic-types/src/StringlyTypedMatrix/index.ts

@@ -8,6 +8,7 @@
 // </text>
 
 export * from "./StringEventID";
+export * from "./StringMediaURI";
 export * from "./StringRoomAlias";
 export * from "./StringRoomID";
 export * from "./StringServerName";