feat: Support matrix: links (#4839)

app/src/main/AndroidManifest.xml

@@ -122,6 +122,17 @@
                 <data android:scheme="https" />
                 <data android:host="matrix.to" />
             </intent-filter>
+            <!--
+              matrix: links
+            -->
+            <intent-filter>
+                <action android:name="android.intent.action.VIEW" />
+
+                <category android:name="android.intent.category.DEFAULT" />
+                <category android:name="android.intent.category.BROWSABLE" />
+
+                <data android:scheme="matrix" />
+            </intent-filter>
             <!--
               links from matrix.to website
             -->

libraries/matrix/api/src/main/kotlin/io/element/android/libraries/matrix/api/permalink/PermalinkParser.kt

@@ -12,6 +12,7 @@ package io.element.android.libraries.matrix.api.permalink
  * element-based domains (e.g. https://app.element.io/#/user/@chagai95:matrix.org) permalinks
  * or matrix.to permalinks (e.g. https://matrix.to/#/@chagai95:matrix.org)
  * or client permalinks (e.g. <clientPermalinkBaseUrl>user/@chagai95:matrix.org)
+ * or matrix: permalinks (e.g. matrix:u/chagai95:matrix.org)
  */
 interface PermalinkParser {
     /**

libraries/matrix/impl/src/main/kotlin/io/element/android/libraries/matrix/impl/permalink/DefaultPermalinkParser.kt

@@ -29,6 +29,7 @@ import javax.inject.Inject
  * element-based domains (e.g. https://app.element.io/#/user/@chagai95:matrix.org) permalinks
  * or matrix.to permalinks (e.g. https://matrix.to/#/@chagai95:matrix.org)
  * or client permalinks (e.g. <clientPermalinkBaseUrl>user/@chagai95:matrix.org)
+ * or matrix: permalinks (e.g. matrix:u/chagai95:matrix.org)
  */
 @ContributesBinding(AppScope::class)
 class DefaultPermalinkParser @Inject constructor(
@@ -40,10 +41,15 @@ class DefaultPermalinkParser @Inject constructor(
      */
     override fun parse(uriString: String): PermalinkData {
         val uri = uriString.toUri()
-        // the client or element-based domain permalinks (e.g. https://app.element.io/#/user/@chagai95:matrix.org) don't have the
-        // mxid in the first param (like matrix.to does - https://matrix.to/#/@chagai95:matrix.org) but rather in the second after /user/ so /user/mxid
-        // so convert URI to matrix.to to simplify parsing process
-        val matrixToUri = matrixToConverter.convert(uri) ?: return PermalinkData.FallbackLink(uri)
+        val matrixToUri = if (uri.scheme == "matrix") {
+            // take matrix: URI as is to [parseMatrixEntityFrom]
+            uri
+        } else {
+            // the client or element-based domain permalinks (e.g. https://app.element.io/#/user/@chagai95:matrix.org) don't have the
+            // mxid in the first param (like matrix.to does - https://matrix.to/#/@chagai95:matrix.org) but rather in the second after /user/ so /user/mxid
+            // so convert URI to matrix.to to simplify parsing process
+            matrixToConverter.convert(uri) ?: return PermalinkData.FallbackLink(uri)
+        }
 
         val result = runCatchingExceptions {
             parseMatrixEntityFrom(matrixToUri.toString())

tools/adb/deeplink_matrix.sh

@@ -0,0 +1,9 @@
+#! /bin/bash
+
+# Copyright 2025 New Vector Ltd.
+#
+# SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-Element-Commercial
+# Please see LICENSE files in the repository root for full details.
+
+adb shell am start -a android.intent.action.VIEW \
+   -d "matrix:r/element-android:matrix.org"