fix: revoked token no longer crashes the app

app/src/main/java/chat/revolt/api/RevoltAPI.kt

@@ -1,6 +1,7 @@
 package chat.revolt.api
 
 import chat.revolt.api.routes.user.fetchSelf
+import chat.revolt.api.routes.user.fetchSelfWithNewToken
 import chat.revolt.api.schemas.CompleteUser
 import io.ktor.client.*
 import io.ktor.client.engine.okhttp.*
@@ -85,6 +86,18 @@ object RevoltAPI {
 
         userCache.clear()
     }
+
+    /**
+     * Checks if a session token is valid.
+     */
+    suspend fun checkSessionToken(token: String): Boolean {
+        return try {
+            fetchSelfWithNewToken(token)
+            true
+        } catch (e: Exception) {
+            false
+        }
+    }
 }
 
 @kotlinx.serialization.Serializable

app/src/main/java/chat/revolt/api/routes/user/User.kt

@@ -1,11 +1,13 @@
 package chat.revolt.api.routes.user
 
 import chat.revolt.api.RevoltAPI
+import chat.revolt.api.RevoltError
 import chat.revolt.api.RevoltHttp
 import chat.revolt.api.RevoltJson
 import chat.revolt.api.schemas.CompleteUser
 import io.ktor.client.request.*
 import io.ktor.client.statement.*
+import kotlinx.serialization.SerializationException
 
 suspend fun fetchSelf(): CompleteUser {
     val response = RevoltHttp.get("/users/@me") {
@@ -13,6 +15,13 @@ suspend fun fetchSelf(): CompleteUser {
     }
         .bodyAsText()
 
+    try {
+        val error = RevoltJson.decodeFromString(RevoltError.serializer(), response)
+        throw Error(error.type)
+    } catch (e: SerializationException) {
+        // Not an error
+    }
+
     val user = RevoltJson.decodeFromString(CompleteUser.serializer(), response)
 
     RevoltAPI.userCache[user.id!!] = user

app/src/main/java/chat/revolt/screens/login/GreeterScreen.kt

@@ -55,7 +55,11 @@ class GreeterViewModel @Inject constructor(
         viewModelScope.launch {
             val token = kvStorage.get("sessionToken")
             if (token != null) {
-                RevoltAPI.setSessionHeader(token)
+                val valid = RevoltAPI.checkSessionToken(token)
+                if (!valid) {
+                    kvStorage.remove("sessionToken")
+                    RevoltAPI.setSessionHeader("")
+                }
             }
 
             RevoltAPI.initialize()

app/src/main/java/chat/revolt/screens/login/LoginScreen.kt

@@ -75,10 +75,14 @@ class LoginViewModel @Inject constructor(
                         "No MFA required. Login is complete! We have a session token: ${response.firstUserHints!!.token}"
                     )
 
-                    fetchSelfWithNewToken(response.firstUserHints.token)
+                    try {
-                    kvStorage.set("sessionToken", response.firstUserHints.token)
+                        fetchSelfWithNewToken(response.firstUserHints.token)
+                        kvStorage.set("sessionToken", response.firstUserHints.token)
 
-                    _navigateTo = "home"
+                        _navigateTo = "home"
+                    } catch (e: Error) {
+                        _error = e.message ?: "Unknown error"
+                    }
                 }
             }
         }

app/src/main/java/chat/revolt/screens/login/MfaScreen.kt

@@ -79,10 +79,14 @@ class MfaScreenViewModel @Inject constructor(
                     "Successfully authorized TOTP. Token: ${response.firstUserHints!!.token}"
                 )
 
-                fetchSelfWithNewToken(response.firstUserHints.token)
+                try {
-                kvStorage.set("sessionToken", response.firstUserHints.token)
+                    fetchSelfWithNewToken(response.firstUserHints.token)
+                    kvStorage.set("sessionToken", response.firstUserHints.token)
 
-                _navigateToHome = true
+                    _navigateToHome = true
+                } catch (e: Error) {
+                    _error = e.message ?: "Unknown error"
+                }
             }
         }
     }
@@ -100,10 +104,14 @@ class MfaScreenViewModel @Inject constructor(
                     "Successfully authorized recovery code. Token: ${response.firstUserHints!!.token}"
                 )
 
-                fetchSelfWithNewToken(response.firstUserHints.token)
+                try {
-                kvStorage.set("sessionToken", response.firstUserHints.token)
+                    fetchSelfWithNewToken(response.firstUserHints.token)
+                    kvStorage.set("sessionToken", response.firstUserHints.token)
 
-                _navigateToHome = true
+                    _navigateToHome = true
+                } catch (e: Error) {
+                    _error = e.message ?: "Unknown error"
+                }
             }
         }
     }