Update login url on URL redirection

app/src/main/java/chat/rocket/android/authentication/server/presentation/VersionCheckView.kt

 package chat.rocket.android.authentication.server.presentation
 
+import okhttp3.HttpUrl
+
 interface VersionCheckView {
     /**
      * Alerts the user about the server version not meeting the recommended server version.
@@ -26,4 +28,9 @@ interface VersionCheckView {
      * Alters the user this protocol is invalid. This is optional.
      */
     fun errorInvalidProtocol() {}
+
+    /**
+     * Updates the server URL after a URL redirection
+     */
+    fun updateServerUrl(url: HttpUrl) {}
 }
\ No newline at end of file

app/src/main/java/chat/rocket/android/authentication/server/ui/ServerFragment.kt

@@ -20,6 +20,7 @@ import chat.rocket.android.util.extensions.*
 import chat.rocket.common.util.ifNull
 import dagger.android.support.AndroidSupportInjection
 import kotlinx.android.synthetic.main.fragment_authentication_server.*
+import okhttp3.HttpUrl
 import javax.inject.Inject
 
 class ServerFragment : Fragment(), ServerView {
@@ -41,6 +42,7 @@ class ServerFragment : Fragment(), ServerView {
     }
 
     private var protocol = "https://"
+    private var ignoreChange = false
 
     override fun onCreate(savedInstanceState: Bundle?) {
         super.onCreate(savedInstanceState)
@@ -72,7 +74,10 @@ class ServerFragment : Fragment(), ServerView {
                         protocol = "https://"
                     }
                     1 -> {
-                        ui{
+                        if (ignoreChange) {
+                            protocol = "http://"
+                        } else {
+                            ui {
                                 AlertDialog.Builder(it)
                                         .setTitle(R.string.msg_warning)
                                         .setMessage(R.string.msg_http_insecure)
@@ -89,6 +94,8 @@ class ServerFragment : Fragment(), ServerView {
                         }
                     }
                 }
+                ignoreChange = false
+            }
 
             override fun onNothingSelected(parent: AdapterView<*>?) {
             }
@@ -174,13 +181,23 @@ class ServerFragment : Fragment(), ServerView {
         showMessage(R.string.msg_invalid_server_protocol)
     }
 
+    override fun updateServerUrl(url: HttpUrl) {
+        if (activity != null && view != null) {
+            if (url.scheme() == "https") text_server_protocol.setSelection(0) else text_server_protocol.setSelection(1)
+            protocol = "${url.scheme()}://"
+
+            val serverUrl = url.toString().removePrefix("${url.scheme()}://")
+            text_server_url.textContent = serverUrl
+        }
+    }
+
     private fun performConnect() {
         ui {
             deepLinkInfo?.let {
                 presenter.deepLink(it)
             }.ifNull {
                 val url = text_server_url.textContent.ifEmpty(text_server_url.hintContent)
-                presenter.connect("${protocol}${url.sanitize()}")
+                presenter.connect("$protocol${url.sanitize()}")
             }
         }
     }

app/src/main/java/chat/rocket/android/server/presentation/CheckServerPresenter.kt

@@ -8,6 +8,7 @@ import chat.rocket.android.util.VersionInfo
 import chat.rocket.android.util.extensions.launchUI
 import chat.rocket.android.util.retryIO
 import chat.rocket.common.RocketChatInvalidProtocolException
+import chat.rocket.common.model.ServerInfo
 import chat.rocket.core.RocketChatClient
 import chat.rocket.core.internal.rest.serverInfo
 import kotlinx.coroutines.experimental.Deferred
@@ -26,7 +27,13 @@ abstract class CheckServerPresenter constructor(private val strategy: CancelStra
             try {
                 currentServer = serverUrl
                 client = factory.create(currentServer)
-                val version = checkServerVersion(serverUrl).await()
+                val serverInfo = retryIO(description = "serverInfo", times = 5) {
+                    client.serverInfo()
+                }
+                if (serverInfo.redirected) {
+                    view.updateServerUrl(serverInfo.url)
+                }
+                val version = checkServerVersion(serverInfo)
                 when (version) {
                     is Version.VersionOk -> {
                         Timber.i("Your version is nice! (Requires: 0.62.0, Yours: ${version.version})")
@@ -55,23 +62,19 @@ abstract class CheckServerPresenter constructor(private val strategy: CancelStra
         }
     }
 
-    internal fun checkServerVersion(serverUrl: String): Deferred<Version> {
-        currentServer = serverUrl
-        return async {
-            val serverInfo = retryIO(description = "serverInfo", times = 5) { client.serverInfo() }
+    private fun checkServerVersion(serverInfo: ServerInfo): Version {
         val thisServerVersion = serverInfo.version
         val isRequiredVersion = isRequiredServerVersion(thisServerVersion)
         val isRecommendedVersion = isRecommendedServerVersion(thisServerVersion)
-            if (isRequiredVersion) {
+        return if (isRequiredVersion) {
             if (isRecommendedVersion) {
                 Timber.i("Your version is nice! (Requires: 0.62.0, Yours: $thisServerVersion)")
-                    return@async Version.VersionOk(thisServerVersion)
+                Version.VersionOk(thisServerVersion)
             } else {
-                    return@async Version.RecommendedVersionWarning(thisServerVersion)
+                Version.RecommendedVersionWarning(thisServerVersion)
             }
         } else {
-                return@async Version.OutOfDateError(thisServerVersion)
-            }
+            Version.OutOfDateError(thisServerVersion)
         }
     }