HTML unescaping for URL preview (#2766)

CHANGES.md

@@ -10,6 +10,7 @@ Improvements 🙌:
 Bugfix 🐛:
  - Duplicate thumbs | Mobile reactions for 👍 and 👎 are not the same as web (#2776)
  - Join room by alias other federation error (#2778)
+ - HTML unescaping for URL preview (#2766)
 
 Translations 🗣:
  -

matrix-sdk-android/src/main/java/org/matrix/android/sdk/internal/session/media/GetPreviewUrlTask.kt

@@ -28,6 +28,7 @@ import org.matrix.android.sdk.internal.network.GlobalErrorReceiver
 import org.matrix.android.sdk.internal.network.executeRequest
 import org.matrix.android.sdk.internal.task.Task
 import org.matrix.android.sdk.internal.util.awaitTransaction
+import org.matrix.android.sdk.internal.util.unescapeHtml
 import java.util.Date
 import javax.inject.Inject
 
@@ -73,9 +74,9 @@ internal class DefaultGetPreviewUrlTask @Inject constructor(
     private fun JsonDict.toPreviewUrlData(url: String): PreviewUrlData {
         return PreviewUrlData(
                 url = (get("og:url") as? String) ?: url,
-                siteName = get("og:site_name") as? String,
+                siteName = (get("og:site_name") as? String)?.unescapeHtml(),
-                title = get("og:title") as? String,
+                title = (get("og:title") as? String)?.unescapeHtml(),
-                description = get("og:description") as? String,
+                description = (get("og:description") as? String)?.unescapeHtml(),
                 mxcUrl = get("og:image") as? String
         )
     }

matrix-sdk-android/src/main/java/org/matrix/android/sdk/internal/util/Html.kt

@@ -0,0 +1,23 @@
+/*
+ * Copyright (c) 2021 New Vector Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.matrix.android.sdk.internal.util
+
+import androidx.core.text.HtmlCompat
+
+internal fun String.unescapeHtml(): String {
+    return HtmlCompat.fromHtml(this, HtmlCompat.FROM_HTML_MODE_LEGACY).toString()
+}