WIP on a WASM wrapper

packages/realm/bindgen/src/templates/wasm-wrapper.ts

@@ -0,0 +1,58 @@
+////////////////////////////////////////////////////////////////////////////
+//
+// Copyright 2024 Realm Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+////////////////////////////////////////////////////////////////////////////
+
+import { TemplateContext } from "@realm/bindgen/context";
+
+import { eslintFormatter } from "../formatters";
+import { generate as generateBase, generateNativeBigIntSupport } from "./base-wrapper";
+
+export function generate(context: TemplateContext): void {
+  const out = context.file("native.wasm.mjs", eslintFormatter);
+
+  out("// This file is generated: Update the spec instead of editing this file directly");
+
+  out(`
+    /*global window, FinalizationRegistry*/
+    import Module from "../../prebuilds/wasm/realm-js-wasm.mjs";
+    const nativeModule = await Module(); // loading WASM 
+    nativeModule.browserInit();
+    export const WeakRef = window.WeakRef;
+  `);
+
+  generateNativeBigIntSupport(out);
+
+  out(`
+    export const Int64 = NativeBigIntSupport; // Browsers always supports BigInt
+  `);
+
+  generateBase({
+    context,
+    out,
+    classExtras(cls) {
+      return `const _${cls.jsName}_registery = (nativeModule.${cls.jsName}_deleter) ? new FinalizationRegistry(nativeModule.${cls.jsName}_deleter) : undefined;`;
+    },
+    emitConstructor(symb, cls) {
+      return `constructor(ptr) { this[${symb}] = ptr; 
+        if (_${cls.jsName}_registery) _${cls.jsName}_registery.register(this, ptr);
+      };`;
+    },
+  });
+
+  context.file("native.wasm.d.mts", eslintFormatter)("export * from './native'");
+  context.file("native.wasm.d.cts", eslintFormatter)("import * as binding from './native'; export = binding;");
+}