From 175aa62a7e4a1d8748059e6a8f5acf01a9ffff47 Mon Sep 17 00:00:00 2001
From: Tony Garnock-Jones <tonyg@leastfixedpoint.com>
Date: Sun, 9 Jun 2024 10:48:17 +0200
Subject: [PATCH] Extract movementDescriptionMessages()

---
 web/vessel.js | 68 ++++++++++++++++++++++++++++-----------------------
 1 file changed, 38 insertions(+), 30 deletions(-)

diff --git a/web/vessel.js b/web/vessel.js
index d41bb5c..7411539 100644
--- a/web/vessel.js
+++ b/web/vessel.js
@@ -173,37 +173,13 @@ function spawnVessel(vesselId, initialHere, _isRoot) {
               break;
             case 'goto':
               if (!isRootVessel(vessel) || !isLocalVessel(cmd.location)) {
-                const oldLocation = location.value;
+                let { outMsg, inMsg } = movementDescriptionMessages(cmd.action,
+                                                                    vessel,
+                                                                    agent,
+                                                                    location.value,
+                                                                    cmd.location);
+                const id = outMsg ? sendEvent(null, location.value, ... outMsg) : null;
                 location.value = cmd.location;
-                let outMsg = void 0, inMsg = void 0;
-                switch (cmd.action) {
-                  case 'initial':
-                    break;
-                  case 'link':
-                    inMsg = [vessel, ` joined the network.`];
-                    break;
-                  case 'give':
-                    outMsg = inMsg = [agent, ` gave `, _theThing(vessel), ` to `, _theThing(cmd.location), `.`];
-                    break;
-                  case 'put':
-                    outMsg = inMsg = [agent, ` put `, _theThing(vessel), ` down in `, _thePlace(cmd.location), `.`];
-                    break;
-                  case 'take':
-                    outMsg = inMsg = [agent, ` picked up `, _theThing(vessel), ` from `, _thePlace(oldLocation), `.`];
-                    break;
-                  case 'drop':
-                    outMsg = inMsg = [agent, ` dropped `, _theThing(vessel), ` in `, _thePlace(cmd.location), `.`];
-                    break;
-                  case 'enter':
-                    outMsg = [vessel, ` entered `, _thePlace(cmd.location), `.`];
-                    inMsg = [vessel, ` left `, _thePlace(oldLocation), ` for `, _thePlace(cmd.location), `.`];
-                    break;
-                  case 'move':
-                  default:
-                    outMsg = inMsg = [agent, ` moved `, _theThing(vessel), ` from `, _thePlace(oldLocation), ` into `, _thePlace(cmd.location), `.`];
-                    break;
-                }
-                const id = outMsg ? sendEvent(null, oldLocation, ... outMsg) : null;
                 if (inMsg) broadcast(id, ... inMsg);
               }
               break;
@@ -254,3 +230,35 @@ function spawnVessel(vesselId, initialHere, _isRoot) {
     }
   });
 }
+
+function movementDescriptionMessages(action, vessel, agent, oldLocation, newLocation) {
+  let outMsg = void 0, inMsg = void 0;
+  switch (action) {
+    case 'initial':
+      break;
+    case 'link':
+      inMsg = [vessel, ` joined the network.`];
+      break;
+    case 'give':
+      outMsg = inMsg = [agent, ` gave `, _theThing(vessel), ` to `, _theThing(newLocation), `.`];
+      break;
+    case 'put':
+      outMsg = inMsg = [agent, ` put `, _theThing(vessel), ` down in `, _thePlace(newLocation), `.`];
+      break;
+    case 'take':
+      outMsg = inMsg = [agent, ` picked up `, _theThing(vessel), ` from `, _thePlace(oldLocation), `.`];
+      break;
+    case 'drop':
+      outMsg = inMsg = [agent, ` dropped `, _theThing(vessel), ` in `, _thePlace(newLocation), `.`];
+      break;
+    case 'enter':
+      outMsg = [vessel, ` entered `, _thePlace(newLocation), `.`];
+      inMsg = [vessel, ` left `, _thePlace(oldLocation), ` for `, _thePlace(newLocation), `.`];
+      break;
+    case 'move':
+    default:
+      outMsg = inMsg = [agent, ` moved `, _theThing(vessel), ` from `, _thePlace(oldLocation), ` into `, _thePlace(newLocation), `.`];
+      break;
+  }
+  return { outMsg, inMsg };
+}