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// Copyright (c) 2026 Cloudflare, Inc.
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// Licensed under the Apache 2.0 license found in the LICENSE file or at:
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//     https://opensource.org/licenses/Apache-2.0
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#pragma once
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#include <workerd/jsg/jsg.h>
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#include <workerd/jsg/modules-new.h>
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#include <workerd/jsg/modules.h>
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#include <workerd/rust/jsg/ffi-inl.h>
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#include <workerd/rust/jsg/ffi.h>
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#include <workerd/rust/jsg/v8.rs.h>
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#include <kj-rs/kj-rs.h>
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#include <rust/cxx.h>
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#include <kj/function.h>
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namespace workerd::rust::jsg {
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// Adapter for registering Rust-implemented modules into the OLD module registry
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// (jsg::ModuleRegistryImpl). Translates Rust ModuleCallback into ModuleInfo.
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template <typename Registry>
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struct RustModuleRegistry: public ::workerd::rust::jsg::ModuleRegistry {
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  virtual ~RustModuleRegistry() = default;
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  RustModuleRegistry(Registry& registry): registry(registry) {}
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  void addBuiltinModule(
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      ::rust::Str specifier, ModuleCallback moduleCallback, ModuleType moduleType) override {
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    ::workerd::jsg::ModuleType jsgModuleType;
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    switch (moduleType) {
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      case ModuleType::Bundle:
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        jsgModuleType = ::workerd::jsg::ModuleType::BUNDLE;
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        break;
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      case ModuleType::Builtin:
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        jsgModuleType = ::workerd::jsg::ModuleType::BUILTIN;
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        break;
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      case ModuleType::Internal:
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        jsgModuleType = ::workerd::jsg::ModuleType::INTERNAL;
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        break;
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      default:
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        KJ_UNREACHABLE;
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    }
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    registry.addBuiltinModule(kj::str(specifier),
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        [kj_specifier = kj::str(specifier), callback = kj::mv(moduleCallback)](
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            ::workerd::jsg::Lock& js, ::workerd::jsg::ModuleRegistry::ResolveMethod,
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            kj::Maybe<const kj::Path&>&) mutable
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        -> kj::Maybe<::workerd::jsg::ModuleRegistry::ModuleInfo> {
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      auto localValue = callback(js.v8Isolate);
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      auto value = local_from_ffi<v8::Value>(kj::mv(localValue));
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      KJ_DASSERT(value->IsObject());
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      using ModuleInfo = ::workerd::jsg::ModuleRegistry::ModuleInfo;
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      using ObjectModuleInfo = ::workerd::jsg::ModuleRegistry::ObjectModuleInfo;
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      return kj::Maybe(
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          ModuleInfo(js, kj_specifier, kj::none, ObjectModuleInfo(js, value.As<v8::Object>())));
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    },
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        jsgModuleType);
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  }
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  Registry& registry;
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};
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// Adapter for registering Rust-implemented modules into the NEW module registry
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// (jsg::modules::ModuleBundle::BuiltinBuilder). Translates Rust ModuleCallback
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// into BuiltinBuilder::addSynthetic calls. Each Rust module callback receives a
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// v8::Isolate* and returns a v8::Local<v8::Value> (the module's default export).
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//
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// Usage:
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//   RustBuiltinModuleAdapter adapter(builder);
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//   ::workerd::rust::api::register_nodejs_modules(adapter);
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struct RustBuiltinModuleAdapter: public ::workerd::rust::jsg::ModuleRegistry {
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  ::workerd::jsg::modules::ModuleBundle::BuiltinBuilder& builder;
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  explicit RustBuiltinModuleAdapter(::workerd::jsg::modules::ModuleBundle::BuiltinBuilder& builder)
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      : builder(builder) {}
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  void addBuiltinModule(
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      ::rust::Str specifier, ModuleCallback moduleCallback, ModuleType moduleType) override {
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    // Convert ::rust::Str to kj::ArrayPtr<const char> for URL parsing.
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    auto specifierPtr = kj::ArrayPtr<const char>(specifier.data(), specifier.size());
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    KJ_IF_SOME(url, ::workerd::jsg::Url::tryParse(specifierPtr)) {
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      builder.addSynthetic(url,
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          [callback = kj::mv(moduleCallback)](::workerd::jsg::Lock& js, const ::workerd::jsg::Url&,
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              const ::workerd::jsg::modules::Module::ModuleNamespace& ns,
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              const ::workerd::jsg::CompilationObserver&) mutable {
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        auto localValue = callback(js.v8Isolate);
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        auto value = local_from_ffi<v8::Value>(kj::mv(localValue));
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        KJ_DASSERT(value->IsObject());
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        ns.setDefault(js, ::workerd::jsg::JsValue(value));
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        return true;
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      });
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    } else {
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      KJ_LOG(WARNING, "Ignoring Rust module with invalid specifier", specifierPtr);
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    }
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  }
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};
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}  // namespace workerd::rust::jsg