Add RemoteDeviceLoader to create RemoteDevice from CryptAuth data.

components/proximity_auth/remote_device_loader.cc

Index: components/proximity_auth/remote_device_loader.cc
diff --git a/components/proximity_auth/remote_device_loader.cc b/components/proximity_auth/remote_device_loader.cc
new file mode 100644
index 0000000000000000000000000000000000000000..b60170371c7723a76a11bd07584d38f50820c7c1
--- /dev/null
+++ b/components/proximity_auth/remote_device_loader.cc
@@ -0,0 +1,76 @@
+// Copyright 2015 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 "components/proximity_auth/remote_device_loader.h"
+
+#include "base/bind.h"
+#include "components/proximity_auth/cryptauth/secure_message_delegate.h"
+#include "components/proximity_auth/logging/logging.h"
+
+namespace proximity_auth {
+
+RemoteDeviceLoader::RemoteDeviceLoader(
+    const std::vector<cryptauth::ExternalDeviceInfo>& unlock_keys,
+    const std::string& user_id,
+    const std::string& user_private_key,
+    scoped_ptr<SecureMessageDelegate> secure_message_delegate)
+    : remaining_unlock_keys_(unlock_keys),
+      user_id_(user_id),
+      user_private_key_(user_private_key),
+      secure_message_delegate_(secure_message_delegate.Pass()),
+      weak_ptr_factory_(this) {}
+
+RemoteDeviceLoader::~RemoteDeviceLoader() {}
+
+void RemoteDeviceLoader::Load(const RemoteDeviceCallback& callback) {
+  DCHECK(callback_.is_null());
+  callback_ = callback;
+  PA_LOG(INFO) << "Loading " << remaining_unlock_keys_.size()
+               << " remote devices";
+
+  if (remaining_unlock_keys_.empty()) {
+    callback_.Run(remote_devices_);
+    return;
+  }
+
+  std::vector<cryptauth::ExternalDeviceInfo> all_unlock_keys =
+      remaining_unlock_keys_;
+
+  for (const auto& unlock_key : all_unlock_keys) {
+    secure_message_delegate_->DeriveKey(
+        user_private_key_, unlock_key.public_key(),
+        base::Bind(&RemoteDeviceLoader::OnPSKDerived,
+                   weak_ptr_factory_.GetWeakPtr(), unlock_key));
+  }
+}
+
+void RemoteDeviceLoader::OnPSKDerived(
+    const cryptauth::ExternalDeviceInfo& unlock_key,
+    const std::string& psk) {
+  std::string public_key = unlock_key.public_key();
+  auto iterator = std::find_if(
+      remaining_unlock_keys_.begin(), remaining_unlock_keys_.end(),
+      [&public_key](const cryptauth::ExternalDeviceInfo& unlock_key) {
+        return unlock_key.public_key() == public_key;
+      });
+
+  DCHECK(iterator != remaining_unlock_keys_.end());
+  remaining_unlock_keys_.erase(iterator);
+  PA_LOG(INFO) << "Derived PSK for " << unlock_key.friendly_device_name()
+               << ", " << remaining_unlock_keys_.size() << " keys remaining.";
+
+  // TODO(tengs): We assume that devices without a |bluetooth_address| field are
+  // BLE devices. Ideally, we should have a separate field for this information.
+  RemoteDevice::BluetoothType bluetooth_type =
+      unlock_key.bluetooth_address().empty() ? RemoteDevice::BLUETOOTH_LE
+                                             : RemoteDevice::BLUETOOTH_CLASSIC;
+  remote_devices_.push_back(RemoteDevice(
+      user_id_, unlock_key.friendly_device_name(), unlock_key.public_key(),
+      bluetooth_type, unlock_key.bluetooth_address(), psk, std::string()));
+
+  if (!remaining_unlock_keys_.size())
+    callback_.Run(remote_devices_);
+}
+
+}  // namespace proximity_auth