Fix BT response schema bug from API-VERSION 2024-01-08

I'm not sure why BT responses all of a sudden stopped returning as
strings and started returning as Gson representations. These changes
seem to mitigate the issue though.

Signed-off-by: Devin Morgan <[email protected]>

forage-android/src/main/java/com/joinforage/forage/android/ecom/services/vault/bt/BTResponseParser.kt

@@ -6,6 +6,7 @@ import com.joinforage.forage.android.core.services.forageapi.network.ForageApiRe
 import com.joinforage.forage.android.core.services.forageapi.network.ForageError
 import com.joinforage.forage.android.core.services.forageapi.network.UnknownErrorApiResponse
 import com.joinforage.forage.android.core.services.vault.VaultResponseParser
+import org.json.JSONObject
 
 internal class BTResponseParser(btRes: Result<Any?>) : VaultResponseParser {
     override val isNullResponse: Boolean = false
@@ -63,9 +64,21 @@ internal class BTResponseParser(btRes: Result<Any?>) : VaultResponseParser {
         return if (!isSuccessful) {
             null
         } else {
-            // the BT response get's parsed as a Map instead of String
-            val jsonResponse = Gson().toJson(vaultResponse)
-            ForageApiResponse.Success(jsonResponse.toString())
+            // BT uses the Gson package under the hood to work with JSON
+            // Unfortunately, they are returning Gson parsed JSON instead
+            // of standard JSON which forces us to use Gson to get back
+            // the original JSON (we return a JSON string in our
+            // ForageApiResponse.Success)
+            val gsonParsedJson = Gson().toJson(vaultResponse)
+
+            // for some really really strange reason, Gson wraps the
+            // actual JSON we care about into top-level "value" JSON
+            // field like so: { "value": <json_result> }
+            // So, annoyingly, we need to unwrap it. Since deferred
+            // payments have an empty response, we need to consider
+            // the case where there is no top-level "value" field
+            val unwrapped = JSONObject(gsonParsedJson).optJSONObject("value") ?: ""
+            ForageApiResponse.Success(unwrapped.toString())
         }
     }
 }