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// Copyright (c) 2017-2022 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/io/io-context.h>
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#include <workerd/jsg/jsg.h>
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namespace workerd {
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template <typename Self>
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class PromiseWrapper {
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 public:
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  template <typename T>
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  static constexpr const char* getName(kj::Promise<T>*) {
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    return "Promise";
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  }
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  // Explicitly disallow V8 handles, which are not safe for the KJ event loop to own directly.
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  template <typename T>
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  static constexpr const char* getName(kj::Promise<v8::Global<T>>*) = delete;
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  template <typename T>
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  static constexpr const char* getName(kj::Promise<v8::Local<T>>*) = delete;
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  template <typename T>
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  static constexpr const char* getName(kj::Promise<jsg::Ref<T>>*) {
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    return "Promise";
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  }
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  // For some reason, this wasn't needed for jsg::V8Ref<T>...
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  template <typename T>
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  v8::Local<v8::Promise> wrap(jsg::Lock& js,
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      v8::Local<v8::Context> context,
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      kj::Maybe<v8::Local<v8::Object>> creator,
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      kj::Promise<T> promise) {
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    auto jsPromise = IoContext::current().awaitIoLegacy(js, kj::mv(promise));
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    return static_cast<Self&>(*this).wrap(js, context, kj::mv(creator), kj::mv(jsPromise));
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  }
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  template <typename T>
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  kj::Maybe<kj::Promise<T>> tryUnwrap(jsg::Lock& js,
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      v8::Local<v8::Context> context,
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      v8::Local<v8::Value> handle,
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      kj::Promise<T>*,
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      kj::Maybe<v8::Local<v8::Object>> parentObject) {
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    auto& wrapper = static_cast<Self&>(*this);
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    auto jsPromise = KJ_UNWRAP_OR_RETURN(
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        wrapper.tryUnwrap(js, context, handle, (jsg::Promise<T>*)nullptr, parentObject), kj::none);
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    return IoContext::current().awaitJs(js, kj::mv(jsPromise));
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  }
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  template <typename T>
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  v8::Local<v8::Context> newContext(v8::Isolate* isolate, kj::Promise<T> value) = delete;
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  template <bool isContext = false, typename T>
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  v8::Local<v8::FunctionTemplate> getTemplate(v8::Isolate* isolate, kj::Promise<T>*) = delete;
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};
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}  // namespace workerd