Fix edge-case where Texture#toString has a NullPointer, fix join requests (#838)

* Fix edge-case where Texture#toString has a NullPointer because gson set a null metadata

Also changes NORMAL name to WIDE since that's the accurate name.

* Fix join requests

Fixes #837

Author: AlexProgrammerDE

protocol/src/main/java/org/geysermc/mcprotocollib/auth/GameProfile.java

@@ -14,7 +14,6 @@
 import java.util.ArrayList;
 import java.util.Base64;
 import java.util.Collections;
-import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
 import java.util.Objects;
@@ -371,7 +370,7 @@ public enum TextureType {
      * The model used for a profile texture.
      */
     public enum TextureModel {
-        NORMAL,
+        WIDE,
         SLIM;
     }
 
@@ -390,7 +389,7 @@ public static class Texture {
          */
         public Texture(String url, Map<String, String> metadata) {
             this.url = url;
-            this.metadata = new HashMap<>(metadata);
+            this.metadata = metadata;
         }
 
         /**
@@ -408,6 +407,10 @@ public String getURL() {
          * @return The metadata value corresponding to the given key.
          */
         public String getMetadata(String key) {
+            if (this.metadata == null) {
+                return null;
+            }
+
             return this.metadata.get(key);
         }
 
@@ -418,7 +421,7 @@ public String getMetadata(String key) {
          */
         public TextureModel getModel() {
             String model = this.getMetadata("model");
-            return model != null && model.equals("slim") ? TextureModel.SLIM : TextureModel.NORMAL;
+            return model != null && model.equals("slim") ? TextureModel.SLIM : TextureModel.WIDE;
         }
 
         /**

protocol/src/main/java/org/geysermc/mcprotocollib/auth/util/HTTPUtils.java

@@ -36,8 +36,11 @@ public static <T> T makeRequest(@Nullable ProxyInfo proxy, URI uri, Object input
             throw new IllegalArgumentException("URI cannot be null.");
         }
 
-        HttpResponse response = createHttpClient(proxy).execute(input == null ? new HttpRequest("GET", uri.toURL()) :
-                new HttpContentRequest("POST", uri.toURL()).setContent(HttpContent.string(GSON.toJson(input))));
+        HttpResponse response = createHttpClient(proxy)
+            .execute(input == null ? new HttpRequest("GET", uri.toURL()) :
+                new HttpContentRequest("POST", uri.toURL())
+                    .setContent(HttpContent.string(GSON.toJson(input)))
+                    .setHeader(Headers.CONTENT_TYPE, ContentTypes.APPLICATION_JSON.toString()));
 
         if (responseType == null) {
             return null;