[Offline pages] Applying TaskQueue to RequestQueue::ChangeRequestsState

components/offline_pages/background/change_requests_state_task.cc

+// 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 "components/offline_pages/background/change_requests_state_task.h"
+
+#include "base/bind.h"
+
+namespace offline_pages {
+
+ChangeRequestsStateTask::ChangeRequestsStateTask(
+    RequestQueueStore* store,
+    const std::vector<int64_t>& request_ids,
+    const SavePageRequest::RequestState new_state,
+    const RequestQueueStore::UpdateCallback& callback)
+    : store_(store),
+      request_ids_(request_ids.begin(), request_ids.end()),
+      new_state_(new_state),
+      callback_(callback),
+      weak_ptr_factory_(this) {}
+
+ChangeRequestsStateTask::~ChangeRequestsStateTask() {}
+
+void ChangeRequestsStateTask::Run() {
+  ReadRequests();
+}
+
+void ChangeRequestsStateTask::ReadRequests() {
+  if (request_ids_.empty()) {
+    CompleteEarly(ItemActionStatus::NOT_FOUND);
+    return;
+  }
+
+  store_->GetRequests(base::Bind(&ChangeRequestsStateTask::SelectItemsToUpdate,
+                                 weak_ptr_factory_.GetWeakPtr()));
+}
+
+void ChangeRequestsStateTask::SelectItemsToUpdate(
+    bool success,
+    std::vector<std::unique_ptr<SavePageRequest>> requests) {
+  if (!success) {
+    CompleteEarly(ItemActionStatus::STORE_ERROR);
+    return;
+  }
+
+  std::vector<SavePageRequest> items_to_update;
+  for (const auto& request : requests) {
+    // If this request is in our list, update it.
+    if (request_ids_.count(request->request_id()) > 0) {
+      request->set_request_state(new_state_);
+      items_to_update.push_back(*request);
+      // Items that are missing before the update will be marked as not found
+      // before the callback.
+      request_ids_.erase(request->request_id());
+    }
+  }
+
+  if (items_to_update.empty()) {
+    CompleteEarly(ItemActionStatus::NOT_FOUND);
+    return;
+  }
+
+  store_->UpdateRequests(items_to_update,
+                         base::Bind(&ChangeRequestsStateTask::UpdateCompleted,
+                                    weak_ptr_factory_.GetWeakPtr()));
+}
+
+void ChangeRequestsStateTask::UpdateCompleted(
+    std::unique_ptr<UpdateRequestsResult> update_result) {
+  CompleteWithStatus(std::move(update_result), ItemActionStatus::NOT_FOUND);
+}
+
+void ChangeRequestsStateTask::CompleteEarly(ItemActionStatus status) {
+  // TODO(fgorski): store_->state() once implemented
+  std::unique_ptr<UpdateRequestsResult> result(
+      new UpdateRequestsResult(StoreState::LOADED));
+  CompleteWithStatus(std::move(result), status);
+}
+
+void ChangeRequestsStateTask::CompleteWithStatus(
+    std::unique_ptr<UpdateRequestsResult> result,
+    ItemActionStatus status) {
+  // Mark items as not found, if they are still in the request IDs set.
+  for (int64_t request_id : request_ids_)
+    result->item_statuses.push_back(std::make_pair(request_id, status));
+  callback_.Run(std::move(result));
+  TaskComplete();
+}
+
+}  // namespace offline_pages