From cec69dfa51ce80fb33d9c516fd5747879c28ab13 Mon Sep 17 00:00:00 2001
From: Trumeet <yuuta@yuuta.moe>
Date: Wed, 13 Jul 2022 12:55:05 -0700
Subject: Refactor WSFrameHandler to isolate the business logic

Signed-off-by: Trumeet <yuuta@yuuta.moe>
---
 .../java/moe/ymc/acron/net/WSFrameHandler.java     | 65 +++++++++++++---------
 1 file changed, 39 insertions(+), 26 deletions(-)

diff --git a/src/main/java/moe/ymc/acron/net/WSFrameHandler.java b/src/main/java/moe/ymc/acron/net/WSFrameHandler.java
index f03fc36..912e73a 100644
--- a/src/main/java/moe/ymc/acron/net/WSFrameHandler.java
+++ b/src/main/java/moe/ymc/acron/net/WSFrameHandler.java
@@ -1,6 +1,7 @@
 package moe.ymc.acron.net;
 
 import com.google.gson.JsonParseException;
+import io.netty.channel.Channel;
 import io.netty.channel.ChannelHandlerContext;
 import io.netty.channel.SimpleChannelInboundHandler;
 import io.netty.handler.codec.http.websocketx.*;
@@ -12,6 +13,7 @@ import moe.ymc.acron.c2s.ReqSetConfig;
 import moe.ymc.acron.c2s.Request;
 import moe.ymc.acron.cmd.CmdQueue;
 import moe.ymc.acron.jvav.Pair;
+import moe.ymc.acron.s2c.Event;
 import moe.ymc.acron.s2c.EventQueue;
 import moe.ymc.acron.s2c.response.EventError;
 import moe.ymc.acron.s2c.response.EventOk;
@@ -69,32 +71,10 @@ public class WSFrameHandler extends SimpleChannelInboundHandler<WebSocketFrame>
             return;
         }
         try {
-            if (request instanceof final ReqCmd reqCmd) {
-                LOGGER.info("Client {} executed a command: `{}`.",
-                        identification.client().id(),
-                        reqCmd.cmd());
-                final Pair<Action, Boolean> res = PolicyChecker.check(identification.client(),
-                        reqCmd.cmd());
-                if (res.l() == Action.DENY) {
-                    ctx.channel().writeAndFlush(Serializer.serialize(new EventError(reqCmd.id(),
-                            EventError.Code.FORBIDDEN.value, "This client is not allowed to " +
-                            "execute this command.")));
-                    return;
-                }
-                // Write it before enqueueing to prevent potential
-                // thread safety issues.
-                ctx.channel().writeAndFlush(Serializer.serialize(new EventOk(id)));
-                CmdQueue.enqueue(id,
-                        res.r(),
-                        ctx.channel(),
-                        reqCmd.config() == null ?
-                                configuration :
-                                convertConfiguration(reqCmd.config()),
-                        reqCmd.cmd());
-            } else if (request instanceof final ReqSetConfig reqSetConfig) {
-                ctx.channel().attr(Attributes.CONFIGURATION).set(convertConfiguration(reqSetConfig));
-                ctx.channel().writeAndFlush(Serializer.serialize(new EventOk(id)));
-            }
+            ctx.channel().writeAndFlush(Serializer.serialize(handle(request,
+                    identification,
+                    configuration,
+                    ctx.channel())));
         } catch (Throwable e) {
             LOGGER.info("An error occurred while processing the request. " +
                             "This may just be a malformed request. " +
@@ -106,6 +86,39 @@ public class WSFrameHandler extends SimpleChannelInboundHandler<WebSocketFrame>
         }
     }
 
+    @NotNull
+    private Event handle(@NotNull Request request,
+                         @NotNull ClientIdentification identification,
+                         @NotNull ClientConfiguration configuration,
+                         @NotNull Channel channel) throws Throwable {
+        if (request instanceof final ReqCmd reqCmd) {
+            LOGGER.info("Client {} executed a command: `{}`.",
+                    identification.client().id(),
+                    reqCmd.cmd());
+            final Pair<Action, Boolean> res = PolicyChecker.check(identification.client(),
+                    reqCmd.cmd());
+            if (res.l() == Action.DENY) {
+                return new EventError(reqCmd.id(),
+                        EventError.Code.FORBIDDEN.value, "This client is not allowed to " +
+                        "execute this command.");
+            }
+            // TODO: Ok event may be sent after executing the command.
+            CmdQueue.enqueue(reqCmd.id(),
+                    res.r(),
+                    channel,
+                    reqCmd.config() == null ?
+                            configuration :
+                            convertConfiguration(reqCmd.config()),
+                    reqCmd.cmd());
+            return new EventOk(request.getId());
+        } else if (request instanceof final ReqSetConfig reqSetConfig) {
+            channel.attr(Attributes.CONFIGURATION).set(convertConfiguration(reqSetConfig));
+            return new EventOk(request.getId());
+        }
+        // This should not occur.
+        throw new IllegalStateException("This should not occur.");
+    }
+
     private ClientConfiguration convertConfiguration(@NotNull ReqSetConfig request) {
         final ServerWorld world;
         if (request.world() != null) {
-- 
cgit v1.2.3