feat: Delegate homeserver

Now if matrix homeserver on matrix.example.com, example.com will be correct too

app/src/main/java/ru/risdeveau/pixeldragon/api/Server.kt

@@ -1,7 +1,7 @@
 /*
- * Created by sweetbread on 22.02.2025, 17:28
+ * Created by sweetbread
  * Copyright (c) 2025. All rights reserved.
- * Last modified 22.02.2025, 17:28
+ * Last modified 03.03.2025, 15:40
  */
 
 package ru.risdeveau.pixeldragon.api
@@ -13,19 +13,24 @@ import org.json.JSONObject
 import ru.risdeveau.pixeldragon.client
 import ru.risdeveau.pixeldragon.homeserver
 
-suspend fun isMatrixServer(url: String): Boolean {
+suspend fun getHomeserver(url: String): String? {
     val r = try { client.get("https://$url/.well-known/matrix/client") }
-    catch (_: Exception) { return false }
+    catch (_: Exception) { return null }
 
-    try { JSONObject(r.bodyAsText()) }
-    catch (_: JSONException) { return false }
+    val json = try { JSONObject(r.bodyAsText()) }
+    catch (_: JSONException) { return null }
 
-    return true
+    if (!json.has("m.homeserver")) return null
+
+    var homeserver = json.getJSONObject("m.homeserver").getString("base_url")
+    if (homeserver.endsWith("/")) homeserver = homeserver.dropLast(1)
+
+    return homeserver
 }
 
 fun mxcToUrl(mxc: String): String {
     val pattern = Regex("mxc://([-a-zA-Z0-9@:%._+~#=]{1,256}\\.[a-zA-Z0-9()]{1,6})/([a-zA-Z]+)")
     val match = pattern.find(mxc)
 
-    return "https://$homeserver/_matrix/client/v1/media/download/${match?.groupValues[1]}/${match?.groupValues[2]}"
+    return "$homeserver/_matrix/client/v1/media/download/${match?.groupValues[1]}/${match?.groupValues[2]}"
 }