Move all components/offline_pages/ files into component/offline_pages/core

components/offline_pages/downloads/download_ui_adapter.h

-// 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.
-
-#ifndef COMPONENTS_OFFLINE_PAGE_DOWNLOADS_DOWNLOAD_UI_ADAPTER_H_
-#define COMPONENTS_OFFLINE_PAGE_DOWNLOADS_DOWNLOAD_UI_ADAPTER_H_
-
-#include <map>
-#include <memory>
-#include <string>
-#include <vector>
-
-#include "base/observer_list.h"
-#include "base/supports_user_data.h"
-#include "components/offline_pages/downloads/download_ui_item.h"
-#include "components/offline_pages/offline_page_model.h"
-#include "components/offline_pages/offline_page_types.h"
-#include "url/gurl.h"
-
-namespace offline_pages {
-// C++ side of the UI Adapter. Mimics DownloadManager/Item/History (since we
-// share UI with Downloads).
-// An instance of this class is owned by OfflinePageModel and is shared between
-// UI components if needed. It manages the cache of DownloadUIItems, so after
-// initial load the UI components can synchronously pull the whoel list or any
-// item by its guid.
-class DownloadUIAdapter : public OfflinePageModel::Observer,
-                          public base::SupportsUserData::Data {
- public:
-  // Observer, normally implemented by UI or a Bridge.
-  class Observer {
-   public:
-    // Invoked when UI items are loaded. GetAllItems/GetItem can now be used.
-    // Must be listened for in order to start getting the items.
-    // If the items are already loaded by the time observer is added, this
-    // callback will be posted right away.
-    virtual void ItemsLoaded() = 0;
-
-    // Invoked when the UI Item was added, usually as a request to download.
-    virtual void ItemAdded(const DownloadUIItem& item) = 0;
-
-    // Invoked when the UI Item was updated. Only guid of the item is guaranteed
-    // to survive the update, all other fields can change.
-    virtual void ItemUpdated(const DownloadUIItem& item) = 0;
-
-    // Invoked when the UI Item was deleted. At this point, only guid remains.
-    virtual void ItemDeleted(const std::string& guid) = 0;
-
-   protected:
-    virtual ~Observer() = default;
-  };
-
-  explicit DownloadUIAdapter(OfflinePageModel* model);
-  ~DownloadUIAdapter() override;
-
-  static DownloadUIAdapter* FromOfflinePageModel(
-      OfflinePageModel* offline_page_model);
-
-  // Checks a client ID for proper namespace and ID format to be shown in the
-  // Downloads Home UI.
-  bool IsVisibleInUI(const ClientId& page);
-
-  // This adapter is potentially shared by UI elements, each of which adds
-  // itself as an observer.
-  // When the last observer si removed, cached list of items is destroyed and
-  // next time the initial loading will take longer.
-  void AddObserver(Observer* observer);
-  void RemoveObserver(Observer* observer);
-
-  // Returns all UI items. The list contains references to items in the cache
-  // and has to be used synchronously.
-  std::vector<const DownloadUIItem*> GetAllItems() const;
-  // May return nullptr if item with specified guid does not exist.
-  const DownloadUIItem* GetItem(const std::string& guid) const;
-
-  // Commands from UI. Start async operations, result is observable
-  // via Observer or directly by the user (as in 'open').
-  void DeleteItem(const std::string& guid);
-  int64_t GetOfflineIdByGuid(const std::string& guid) const;
-
-  // OfflinePageModel::Observer
-  void OfflinePageModelLoaded(OfflinePageModel* model) override;
-  void OfflinePageModelChanged(OfflinePageModel* model) override;
-  void OfflinePageDeleted(int64_t offline_id,
-                          const ClientId& client_id) override;
-
- private:
-  enum class State {
-    NOT_LOADED,
-    LOADING,
-    LOADED
-  };
-
-  struct ItemInfo {
-    explicit ItemInfo(const OfflinePageItem& page);
-    ~ItemInfo();
-
-    std::unique_ptr<DownloadUIItem> ui_item;
-    // Additional cached data, not exposed to UI through DownloadUIItem.
-    int64_t offline_id;
-
-   private:
-    DISALLOW_COPY_AND_ASSIGN(ItemInfo);
-  };
-
-  typedef std::map<std::string, std::unique_ptr<ItemInfo>> DownloadUIItems;
-
-  void LoadCache();
-  void ClearCache();
-
-  // Task callbacks.
-  void OnOfflinePagesLoaded(const MultipleOfflinePageItemResult& pages);
-  void NotifyItemsLoaded(Observer* observer);
-  void OnOfflinePagesChanged(const MultipleOfflinePageItemResult& pages);
-  void OnDeletePagesDone(DeletePageResult result);
-
-  // Always valid, this class is a member of the model.
-  OfflinePageModel* model_;
-
-  State state_;
-
-  // The cache of UI items. The key is DownloadUIItem.guid.
-  DownloadUIItems items_;
-
-  // The observers.
-  base::ObserverList<Observer> observers_;
-  int observers_count_;
-
-  base::WeakPtrFactory<DownloadUIAdapter> weak_ptr_factory_;
-
-  DISALLOW_COPY_AND_ASSIGN(DownloadUIAdapter);
-};
-
-}  // namespace offline_pages
-
-#endif  // COMPONENTS_OFFLINE_PAGE_DOWNLOADS_DOWNLOAD_UI_ADAPTER_H_