Skeleton code for propagating UI to DownloadShelf for OfflineItems

This CL introduces the skeleton UI code for OfflineItems.
see https://docs.google.com/document/d/1xDRCoDYnOb9PvwJ8juSmG75jsE-YKzNomCMaoFtQWtQ/edit#

BUG=881499

Change-Id: Ie31f6bcc77c65a4343f2e5a0be54f3b9b5fdd5bc
Reviewed-on: https://chromium-review.googlesource.com/1211445
Commit-Queue: Min Qin <qinmin@chromium.org>
Reviewed-by: Shakti Sahu <shaktisahu@chromium.org>
Cr-Commit-Position: refs/heads/master@{#589720}

chrome/browser/BUILD.gn

@@ -439,6 +439,12 @@ jumbo_split_static_library("browser") {
     "download/drag_download_item.h",
     "download/image_thumbnail_request.cc",
     "download/image_thumbnail_request.h",
+    "download/offline_item_model.cc",
+    "download/offline_item_model.h",
+    "download/offline_item_model_manager.cc",
+    "download/offline_item_model_manager.h",
+    "download/offline_item_model_manager_factory.cc",
+    "download/offline_item_model_manager_factory.h",
     "download/offline_item_utils.cc",
     "download/offline_item_utils.h",
     "download/save_package_file_picker.cc",
@@ -2569,6 +2575,8 @@ jumbo_split_static_library("browser") {
       "download/download_shelf.h",
       "download/download_shelf_context_menu.cc",
       "download/download_shelf_context_menu.h",
+      "download/download_shelf_controller.cc",
+      "download/download_shelf_controller.h",
       "feedback/feedback_dialog_utils.cc",
       "feedback/feedback_dialog_utils.h",
       "feedback/feedback_profile_observer.cc",

chrome/browser/download/download_shelf_controller.cc

+// Copyright 2018 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 "chrome/browser/download/download_shelf_controller.h"
+
+#include "chrome/browser/download/offline_item_model_manager.h"
+#include "chrome/browser/download/offline_item_model_manager_factory.h"
+#include "chrome/browser/ui/browser_finder.h"
+#include "chrome/browser/ui/browser_window.h"
+#include "components/offline_items_collection/core/offline_item.h"
+
+using offline_items_collection::OfflineItemState;
+
+DownloadShelfController::DownloadShelfController(Profile* profile)
+    : profile_(profile) {}
+
+DownloadShelfController::~DownloadShelfController() = default;
+
+void DownloadShelfController::OnItemsAdded(
+    const OfflineContentProvider::OfflineItemList& items) {
+  for (const auto& item : items)
+    OnItemUpdated(item);
+}
+
+void DownloadShelfController::OnItemRemoved(const ContentId& id) {
+  OfflineItemModelManagerFactory::GetForBrowserContext(profile_)
+      ->RemoveOfflineItemModel(id);
+}
+
+void DownloadShelfController::OnItemUpdated(const OfflineItem& item) {
+  if (item.state == OfflineItemState::CANCELLED)
+    return;
+
+  OfflineItemModelManager* manager =
+      OfflineItemModelManagerFactory::GetForBrowserContext(profile_);
+  OfflineItemModel* model = manager->GetOrCreateOfflineItemModel(item);
+
+  if (!model->was_ui_notified()) {
+    OnNewOfflineItemReady(item);
+    model->set_was_ui_notified(true);
+  }
+}
+
+void DownloadShelfController::OnNewOfflineItemReady(const OfflineItem& item) {
+  Browser* browser = browser = chrome::FindLastActiveWithProfile(profile_);
+
+  if (browser && browser->window()) {
+    // Add the offline item to DownloadShelf in the browser window.
+  }
+}

chrome/browser/download/download_shelf_controller.h

+// Copyright 2018 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.
+
+#ifndef CHROME_BROWSER_DOWNLOAD_DOWNLOAD_SHELF_CONTROLLER_H_
+#define CHROME_BROWSER_DOWNLOAD_DOWNLOAD_SHELF_CONTROLLER_H_
+
+#include <map>
+
+#include "base/macros.h"
+#include "chrome/browser/download/offline_item_model.h"
+#include "components/offline_items_collection/core/offline_content_provider.h"
+
+class Profile;
+
+using ContentId = offline_items_collection::ContentId;
+using OfflineContentProvider = offline_items_collection::OfflineContentProvider;
+using OfflineItem = offline_items_collection::OfflineItem;
+
+// Class for notifying UI when an OfflineItem should be displayed.
+class DownloadShelfController : public OfflineContentProvider::Observer {
+ public:
+  explicit DownloadShelfController(Profile* profile);
+  ~DownloadShelfController() override;
+
+ private:
+  // OfflineContentProvider::Observer implementation.
+  void OnItemsAdded(
+      const OfflineContentProvider::OfflineItemList& items) override;
+  void OnItemRemoved(const ContentId& id) override;
+  void OnItemUpdated(const OfflineItem& item) override;
+
+  // Called when a new OfflineItem is to be displayed on UI.
+  void OnNewOfflineItemReady(const OfflineItem& item);
+
+  Profile* profile_;
+
+  DISALLOW_COPY_AND_ASSIGN(DownloadShelfController);
+};
+
+#endif  // CHROME_BROWSER_DOWNLOAD_DOWNLOAD_SHELF_CONTROLLER_H_

chrome/browser/download/offline_item_model.cc

+// Copyright 2018 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 "chrome/browser/download/offline_item_model.h"
+
+OfflineItemModel::OfflineItemModel(
+    const offline_items_collection::OfflineItem& offline_item)
+    : was_ui_notified_(false) {}
+
+OfflineItemModel::~OfflineItemModel() = default;

chrome/browser/download/offline_item_model.h

+// Copyright 2018 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.
+
+#ifndef CHROME_BROWSER_DOWNLOAD_OFFLINE_ITEM_MODEL_H_
+#define CHROME_BROWSER_DOWNLOAD_OFFLINE_ITEM_MODEL_H_
+
+#include "components/offline_items_collection/core/offline_item.h"
+
+// This class is an abstraction for common UI tasks and properties associated
+// with an OfflineItem.
+class OfflineItemModel {
+ public:
+  // Constructs a OfflineItemModel.
+  explicit OfflineItemModel(
+      const offline_items_collection::OfflineItem& offline_item);
+  ~OfflineItemModel();
+
+  bool was_ui_notified() const { return was_ui_notified_; }
+
+  void set_was_ui_notified(bool was_ui_notified) {
+    was_ui_notified_ = was_ui_notified;
+  }
+
+ private:
+  bool was_ui_notified_;
+
+  DISALLOW_COPY_AND_ASSIGN(OfflineItemModel);
+};
+
+#endif  // CHROME_BROWSER_DOWNLOAD_OFFLINE_ITEM_MODEL_H_

chrome/browser/download/offline_item_model_manager.cc

+// Copyright 2018 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 "chrome/browser/download/offline_item_model_manager.h"
+
+OfflineItemModelManager::OfflineItemModelManager() = default;
+
+OfflineItemModelManager::~OfflineItemModelManager() = default;
+
+OfflineItemModel* OfflineItemModelManager::GetOrCreateOfflineItemModel(
+    const OfflineItem& offline_item) {
+  auto it = offline_item_models_.find(offline_item.id);
+  if (it != offline_item_models_.end())
+    return it->second.get();
+  offline_item_models_[offline_item.id] =
+      std::make_unique<OfflineItemModel>(offline_item);
+  return offline_item_models_[offline_item.id].get();
+}
+
+void OfflineItemModelManager::RemoveOfflineItemModel(const ContentId& id) {
+  offline_item_models_.erase(id);
+}

chrome/browser/download/offline_item_model_manager.h

+// Copyright 2018 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.
+
+#ifndef CHROME_BROWSER_DOWNLOAD_OFFLINE_ITEM_MODEL_MANAGER_H_
+#define CHROME_BROWSER_DOWNLOAD_OFFLINE_ITEM_MODEL_MANAGER_H_
+
+#include <memory>
+
+#include "chrome/browser/download/offline_item_model.h"
+#include "components/keyed_service/core/keyed_service.h"
+#include "components/offline_items_collection/core/offline_item.h"
+
+using ContentId = offline_items_collection::ContentId;
+using OfflineItem = offline_items_collection::OfflineItem;
+
+// Class for managing all the OfflineModels for a profile.
+class OfflineItemModelManager : public KeyedService {
+ public:
+  // Constructs a OfflineItemModelManager.
+  OfflineItemModelManager();
+  ~OfflineItemModelManager() override;
+
+  // Returns the OfflineItemModel for the ContentId, if not found, an empty
+  // OfflineItemModel will be created and returned.
+  OfflineItemModel* GetOrCreateOfflineItemModel(
+      const OfflineItem& offline_item);
+
+  void RemoveOfflineItemModel(const ContentId& id);
+
+ private:
+  std::map<ContentId, std::unique_ptr<OfflineItemModel>> offline_item_models_;
+
+  DISALLOW_COPY_AND_ASSIGN(OfflineItemModelManager);
+};
+
+#endif  // CHROME_BROWSER_DOWNLOAD_OFFLINE_ITEM_MODEL_MANAGER_H_

chrome/browser/download/offline_item_model_manager_factory.cc

+// Copyright 2018 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 "chrome/browser/download/offline_item_model_manager_factory.h"
+
+#include "base/memory/singleton.h"
+#include "chrome/browser/download/offline_item_model_manager.h"
+#include "components/keyed_service/content/browser_context_dependency_manager.h"
+#include "content/public/browser/browser_context.h"
+
+// static
+OfflineItemModelManagerFactory* OfflineItemModelManagerFactory::GetInstance() {
+  return base::Singleton<OfflineItemModelManagerFactory>::get();
+}
+
+// static
+OfflineItemModelManager* OfflineItemModelManagerFactory::GetForBrowserContext(
+    content::BrowserContext* context) {
+  return static_cast<OfflineItemModelManager*>(
+      GetInstance()->GetServiceForBrowserContext(context, true));
+}
+
+OfflineItemModelManagerFactory::OfflineItemModelManagerFactory()
+    : BrowserContextKeyedServiceFactory(
+          "OfflineItemModelManager",
+          BrowserContextDependencyManager::GetInstance()) {}
+
+OfflineItemModelManagerFactory::~OfflineItemModelManagerFactory() = default;
+
+KeyedService* OfflineItemModelManagerFactory::BuildServiceInstanceFor(
+    content::BrowserContext* context) const {
+  return new OfflineItemModelManager();
+}

chrome/browser/download/offline_item_model_manager_factory.h

+// Copyright 2018 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.
+
+#ifndef CHROME_BROWSER_DOWNLOAD_OFFLINE_ITEM_MODEL_MANAGER_FACTORY_H_
+#define CHROME_BROWSER_DOWNLOAD_OFFLINE_ITEM_MODEL_MANAGER_FACTORY_H_
+
+#include "base/macros.h"
+#include "components/keyed_service/content/browser_context_keyed_service_factory.h"
+
+class OfflineItemModelManager;
+
+namespace base {
+template <typename T>
+struct DefaultSingletonTraits;
+}  // namespace base
+
+namespace content {
+class BrowserContext;
+}  // namespace content
+
+// This class is the main access point for an OfflineItemModelManager.  It is
+// responsible for building the OfflineItemModelManager and associating it with
+// a particular content::BrowserContext.
+class OfflineItemModelManagerFactory
+    : public BrowserContextKeyedServiceFactory {
+ public:
+  // Returns a singleton instance of an OfflineItemModelManagerFactory.
+  static OfflineItemModelManagerFactory* GetInstance();
+
+  // Returns the OfflineItemModelManager associated with |context| or creates
+  // and associates one if it doesn't exist.
+  static OfflineItemModelManager* GetForBrowserContext(
+      content::BrowserContext* context);
+
+ private:
+  friend struct base::DefaultSingletonTraits<OfflineItemModelManagerFactory>;
+
+  OfflineItemModelManagerFactory();
+  ~OfflineItemModelManagerFactory() override;
+
+  // BrowserContextKeyedServiceFactory implementation.
+  KeyedService* BuildServiceInstanceFor(
+      content::BrowserContext* context) const override;
+
+  DISALLOW_COPY_AND_ASSIGN(OfflineItemModelManagerFactory);
+};
+
+#endif  // CHROME_BROWSER_DOWNLOAD_OFFLINE_ITEM_MODEL_MANAGER_FACTORY_H_