// Copyright 2016 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "modules/webauth/WebAuthentication.h"

#include <stdint.h>

#include "bindings/core/v8/ScriptPromise.h"
#include "bindings/core/v8/ScriptPromiseResolver.h"
#include "core/dom/DOMException.h"
#include "core/dom/Document.h"
#include "core/dom/ExceptionCode.h"
#include "core/frame/LocalFrame.h"
#include "modules/webauth/RelyingPartyAccount.h"
#include "modules/webauth/ScopedCredential.h"
#include "modules/webauth/ScopedCredentialOptions.h"
#include "modules/webauth/ScopedCredentialParameters.h"
#include "public/platform/InterfaceProvider.h"

namespace {
const char kNoAuthenticatorError[] = "Authenticator unavailable.";
}  // anonymous namespace

namespace mojo {

using webauth::mojom::blink::RelyingPartyAccount;
using webauth::mojom::blink::RelyingPartyAccountPtr;
using webauth::mojom::blink::ScopedCredentialOptions;
using webauth::mojom::blink::ScopedCredentialOptionsPtr;
using webauth::mojom::blink::ScopedCredentialParameters;
using webauth::mojom::blink::ScopedCredentialParametersPtr;
using webauth::mojom::blink::ScopedCredentialDescriptor;
using webauth::mojom::blink::ScopedCredentialType;
using webauth::mojom::blink::Transport;

// TODO(kpaulhamus): Make this a TypeConverter
Vector<uint8_t> ConvertBufferSource(const blink::BufferSource& buffer) {
  DCHECK(buffer.isNull());
  Vector<uint8_t> vector;
  if (buffer.isArrayBuffer()) {
    vector.Append(static_cast<uint8_t*>(buffer.getAsArrayBuffer()->Data()),
                  buffer.getAsArrayBuffer()->ByteLength());
  } else {
    vector.Append(static_cast<uint8_t*>(
                      buffer.getAsArrayBufferView().View()->BaseAddress()),
                  buffer.getAsArrayBufferView().View()->byteLength());
  }
  return vector;
}

// TODO(kpaulhamus): Make this a TypeConverter
ScopedCredentialType ConvertScopedCredentialType(const String& cred_type) {
  if (cred_type == "ScopedCred")
    return ScopedCredentialType::SCOPEDCRED;
  NOTREACHED();
  return ScopedCredentialType::SCOPEDCRED;
}

// TODO(kpaulhamus): Make this a TypeConverter
Transport ConvertTransport(const String& transport) {
  if (transport == "usb")
    return Transport::USB;
  if (transport == "nfc")
    return Transport::NFC;
  if (transport == "ble")
    return Transport::BLE;
  NOTREACHED();
  return Transport::USB;
}

RelyingPartyAccountPtr ConvertRelyingPartyAccount(
    const blink::RelyingPartyAccount& account_information,
    blink::ScriptPromiseResolver* resolver) {
  auto mojo_account = RelyingPartyAccount::New();

  mojo_account->relying_party_display_name =
      account_information.rpDisplayName();
  mojo_account->display_name = account_information.displayName();
  mojo_account->id = account_information.id();
  mojo_account->name = account_information.name();
  mojo_account->image_url = account_information.imageURL();
  return mojo_account;
}

// TODO(kpaulhamus): Make this a TypeConverter
ScopedCredentialOptionsPtr ConvertScopedCredentialOptions(
    const blink::ScopedCredentialOptions options,
    blink::ScriptPromiseResolver* resolver) {
  auto mojo_options = ScopedCredentialOptions::New();
  mojo_options->timeout_seconds = options.timeoutSeconds();
  mojo_options->relying_party_id = options.rpId();

  // Adds the excludeList members (which are ScopedCredentialDescriptors)
  for (const auto& descriptor : options.excludeList()) {
    auto mojo_descriptor = ScopedCredentialDescriptor::New();
    mojo_descriptor->type = ConvertScopedCredentialType(descriptor.type());
    mojo_descriptor->id = ConvertBufferSource(descriptor.id());
    for (const auto& transport : descriptor.transports())
      mojo_descriptor->transports.push_back(ConvertTransport(transport));
    mojo_options->exclude_list.push_back(std::move(mojo_descriptor));
  }
  // TODO(kpaulhamus): add AuthenticationExtensions;
  return mojo_options;
}

// TODO(kpaulhamus): Make this a TypeConverter
ScopedCredentialParametersPtr ConvertScopedCredentialParameter(
    const blink::ScopedCredentialParameters parameter,
    blink::ScriptPromiseResolver* resolver) {
  auto mojo_parameter = ScopedCredentialParameters::New();
  mojo_parameter->type = ConvertScopedCredentialType(parameter.type());
  // TODO(kpaulhamus): add AlgorithmIdentifier
  return mojo_parameter;
}
}  // namespace mojo

namespace blink {

WebAuthentication::WebAuthentication(LocalFrame& frame)
    : ContextLifecycleObserver(frame.GetDocument()) {
  frame.GetInterfaceProvider()->GetInterface(
      mojo::MakeRequest(&authenticator_));
  authenticator_.set_connection_error_handler(ConvertToBaseCallback(
      WTF::Bind(&WebAuthentication::OnAuthenticatorConnectionError,
                WrapWeakPersistent(this))));
}

WebAuthentication::~WebAuthentication() {
  // |authenticator_| may still be valid but there should be no more
  // outstanding requests because each holds a persistent handle to this object.
  DCHECK(authenticator_requests_.IsEmpty());
}

void WebAuthentication::Dispose() {}

ScriptPromise WebAuthentication::makeCredential(
    ScriptState* script_state,
    const RelyingPartyAccount& account_information,
    const HeapVector<ScopedCredentialParameters> crypto_parameters,
    const BufferSource& attestation_challenge,
    ScopedCredentialOptions& options) {
  if (!authenticator_) {
    return ScriptPromise::RejectWithDOMException(
        script_state, DOMException::Create(kNotSupportedError));
  }

  ScriptPromiseResolver* resolver = ScriptPromiseResolver::Create(script_state);
  ScriptPromise promise = resolver->Promise();

  // TODO(kpaulhamus) validate parameters according to spec
  auto account =
      mojo::ConvertRelyingPartyAccount(account_information, resolver);
  Vector<uint8_t> buffer = mojo::ConvertBufferSource(attestation_challenge);
  auto opts = mojo::ConvertScopedCredentialOptions(options, resolver);
  Vector<webauth::mojom::blink::ScopedCredentialParametersPtr> parameters;
  for (const auto& parameter : crypto_parameters) {
    parameters.push_back(
        mojo::ConvertScopedCredentialParameter(parameter, resolver));
  }

  authenticator_requests_.insert(resolver);
  authenticator_->MakeCredential(
      std::move(account), std::move(parameters), buffer, std::move(opts),
      ConvertToBaseCallback(Bind(&WebAuthentication::OnMakeCredential,
                                 WrapPersistent(this),
                                 WrapPersistent(resolver))));
  return promise;
}

ScriptPromise WebAuthentication::getAssertion(
    ScriptState* script_state,
    const BufferSource& assertion_challenge,
    const AuthenticationAssertionOptions& options) {
  NOTREACHED();
  return ScriptPromise();
}

void WebAuthentication::ContextDestroyed(ExecutionContext*) {
  authenticator_.reset();
  authenticator_requests_.clear();
}

void WebAuthentication::OnAuthenticatorConnectionError() {
  authenticator_.reset();
  for (ScriptPromiseResolver* resolver : authenticator_requests_) {
    resolver->Reject(
        DOMException::Create(kNotFoundError, kNoAuthenticatorError));
  }
  authenticator_requests_.clear();
}

void WebAuthentication::OnMakeCredential(
    ScriptPromiseResolver* resolver,
    Vector<webauth::mojom::blink::ScopedCredentialInfoPtr> credentials) {
  if (!MarkRequestComplete(resolver))
    return;

  HeapVector<Member<ScopedCredentialInfo>> scoped_credentials;
  for (auto& credential : credentials) {
    if (credential->client_data.IsEmpty() ||
        credential->attestation.IsEmpty()) {
      resolver->Reject(
          DOMException::Create(kNotFoundError, "No credentials returned."));
    }
    DOMArrayBuffer* client_data_buffer = DOMArrayBuffer::Create(
        static_cast<void*>(&credential->client_data.front()),
        credential->client_data.size());

    DOMArrayBuffer* attestation_buffer = DOMArrayBuffer::Create(
        static_cast<void*>(&credential->attestation.front()),
        credential->attestation.size());

    scoped_credentials.push_back(
        ScopedCredentialInfo::Create(client_data_buffer, attestation_buffer));
  }
  resolver->Resolve();
}

bool WebAuthentication::MarkRequestComplete(ScriptPromiseResolver* resolver) {
  auto request_entry = authenticator_requests_.find(resolver);
  if (request_entry == authenticator_requests_.end())
    return false;
  authenticator_requests_.erase(request_entry);
  return true;
}

DEFINE_TRACE(WebAuthentication) {
  visitor->Trace(authenticator_requests_);
  ContextLifecycleObserver::Trace(visitor);
}

}  // namespace blink