From f540b41d730fdc2752a127b46c63c0b4040d8297 Mon Sep 17 00:00:00 2001
From: Tony Garnock-Jones <tonyg@leastfixedpoint.com>
Date: Sat, 11 Dec 2021 15:43:32 +0100
Subject: [PATCH] Optional tracing/dumping for Dataspace

---
 packages/core/src/runtime/dataspace.ts | 26 ++++++++++++++++++--------
 1 file changed, 18 insertions(+), 8 deletions(-)

diff --git a/packages/core/src/runtime/dataspace.ts b/packages/core/src/runtime/dataspace.ts
index 9a7ed18..431b082 100644
--- a/packages/core/src/runtime/dataspace.ts
+++ b/packages/core/src/runtime/dataspace.ts
@@ -1,24 +1,34 @@
 /// SPDX-License-Identifier: GPL-3.0-or-later
 /// SPDX-FileCopyrightText: Copyright © 2016-2021 Tony Garnock-Jones <tonyg@leastfixedpoint.com>
 
-import { IdentityMap, stringify } from '@preserves/core';
+import { IdentityMap } from '@preserves/core';
 import { Index } from './skeleton.js';
 import { Actor, Assertion, Entity, Facet, Handle, LocalAction, Ref, Turn } from './actor.js';
 import { fromObserve, Observe, toObserve } from '../gen/dataspace.js';
 import * as P from '../gen/dataspacePatterns.js';
 
+export type DataspaceOptions {
+    tracer?: (event: '+' | '-' | '!', assertion: Assertion, dataspace: Dataspace) => void,
+    dumpIndex?: boolean,
+};
+
 export class Dataspace implements Partial<Entity> {
+    readonly options: DataspaceOptions;
     readonly index = new Index();
     readonly handleMap = new IdentityMap<Handle, [Assertion, Observe | undefined]>();
 
+    constructor(options?: DataspaceOptions) {
+        this.options = options ?? {};
+    }
+
     assert(v: Assertion, handle: Handle): void {
-        // console.log('+', stringify(v));
+        this.options.tracer?.('+', v, this);
         this.index.addAssertion(v);
         const o = toObserve(v);
         if (o !== void 0) {
             this.index.addObserver(o.pattern, o.observer);
         }
-        // this.index.dump();
+        if (this.options.dumpIndex ?? false) this.index.dump();
         this.handleMap.set(handle, [v, o]);
     }
 
@@ -26,23 +36,23 @@ export class Dataspace implements Partial<Entity> {
         const entry = this.handleMap.get(handle);
         if (entry === void 0) return;
         const [v, o] = entry;
-        // console.log('-', stringify(v));
+        this.options.tracer?.('-', v, this);
         if (o !== void 0) {
             this.index.removeObserver(o.pattern, o.observer);
         }
         this.index.removeAssertion(v);
-        // this.index.dump();
+        if (this.options.dumpIndex ?? false) this.index.dump();
     }
 
     message(v: Assertion): void {
-        // console.log('!', stringify(v));
+        this.options.tracer?.('!', v, this);
         this.index.deliverMessage(v);
     }
 
-    static boot(bootProc: (ds: Ref) => void): Actor {
+    static boot(bootProc: (ds: Ref) => void, options?: DataspaceOptions): Actor {
         return Actor.boot(() => {
             Turn.activeFacet.preventInertCheck();
-            const ds = Turn.active.ref(new Dataspace());
+            const ds = Turn.active.ref(new Dataspace(options));
             bootProc(ds);
         });
     }