Fix hatBlockMatches and reduce kludginess a bit

Stop monkey-patching the current thread and just make a new one. A bit
slower but at least it doesn't completely mess up the thread state.

src/audio/audio-target.ts

@@ -45,9 +45,11 @@ export default class AudioTarget {
         source.connect(this.destinationNode);
         this.playingBuffers.set(sound, source);
 
-        return new Promise(resolve => {
+        return new Promise<void>(resolve => {
             source.start();
-            source.addEventListener('ended', resolve, {once: true});
+            source.addEventListener('ended', () => {
+                resolve();
+            }, {once: true});
         });
     }
 

src/interpreter/thread.ts

@@ -141,20 +141,24 @@ export default class Thread {
     }
 
     hatBlockMatches(event: TypedEvent): boolean {
-        // Make sure the thread runs so we can check the hat block.
-        const threadWasDone = this.status === ThreadStatus.DONE;
-        if (threadWasDone) this.restart(event);
-
         const protoBlock = this.topBlock.proto as SomeProtoBlock;
         if (protoBlock.hat?.type !== 'event') return false;
+        if (!(event instanceof protoBlock.hat.event)) return false;
+
+        const hatThread = new Thread(
+            this.script,
+            this.target,
+            this.blockContext,
+            event,
+        );
 
         // Hats can be started in the middle of executing other scripts (e.g. "broadcast"), so we need to store
         // and restore the previous target and thread.
         const oldTarget = this.blockContext.target;
         const oldThread = this.blockContext.thread;
 
         this.blockContext.target = this.target;
-        this.blockContext.thread = this;
+        this.blockContext.thread = hatThread;
 
         const generator = protoBlock.execute(
             this.topBlock.inputValues,
@@ -178,11 +182,6 @@ export default class Thread {
         }
 
         // Restore the previous target and thread.
-        if (threadWasDone) {
-            this.retire();
-        } else {
-            this.resume();
-        }
         this.blockContext.target = oldTarget;
         this.blockContext.thread = oldThread;
 

todo.md

@@ -23,6 +23,9 @@
 - Apply proper viewbox offset to SVG skin rotation centers (done)
 - Draw pen lines with instancing (no longer planned; tested and has no performance benefit)
 - Really small sprites should trigger "touching" blocks (see: griffpatch's Ball Physics Scroll v0.4)
+- Clones' audio shouldn't stop playing on clone deletion, and clone sounds should cut off other clones' sounds
+  - Tricky because we don't want to leak a bunch of audio nodes
+  - We can't share the AudioTarget between all clones because the effects are distinct
 - Revamp block introspection API
     - want to be able to type ctx.evaluate properly
     - specify "only accept blocks returning X"