Refactor Reading List Model to use URL as key.

components/reading_list/ios/reading_list_model.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_READING_LIST_IOS_READING_LIST_MODEL_H_
 #define COMPONENTS_READING_LIST_IOS_READING_LIST_MODEL_H_
 
 #include <memory>
 #include <string>
 #include <vector>
 
 #include "base/callback.h"
 #include "base/observer_list.h"
 #include "base/threading/non_thread_safe.h"
 #include "components/reading_list/ios/reading_list_entry.h"
 #include "components/reading_list/ios/reading_list_model_observer.h"
 
 class GURL;
-class ReadingListEntry;
 class ReadingListModel;
 class ScopedReadingListBatchUpdate;
 
 namespace syncer {
 class ModelTypeSyncBridge;
 }
 
 // The reading list model contains two list of entries: one of unread urls, the
 // other of read ones. This object should only be accessed from one thread
 // (Usually the main thread). The observers callbacks are also sent on the main
@@ skipping 16 matching lines @@
   // This method is reentrant, i.e. several batch updates may take place at the
   // same time.
   // Returns a scoped batch update object that should be retained while the
   // batch update is performed. Deallocating this object will inform model that
   // the batch update has completed.
   std::unique_ptr<ScopedReadingListBatchUpdate> BeginBatchUpdates();
 
   // Creates a batch token that will freeze the model while in scope.
   virtual std::unique_ptr<ScopedReadingListBatchUpdate> CreateBatchToken();
 
-  // Returns the size of read and unread entries.
+  // Returns a vector of URLs in the model. The order of the URL is not
+  // specified and can vary on successive calls.
+  virtual const std::vector<GURL> Keys() const = 0;
+
+  // Returns the total number of entries in the model.
+  virtual size_t size() const = 0;
+
+  // Returns the total number of unread entries in the model.
   virtual size_t unread_size() const = 0;
-  virtual size_t read_size() const = 0;
 
   // Returns true if there are entries in the model that were not seen by the
   // user yet. Reset to true when new unread entries are added. Reset to false
   // when ResetUnseenEntries is called.
   virtual bool HasUnseenEntries() const = 0;
   virtual void ResetUnseenEntries() = 0;
 
-  // TODO(659099): Remove methods.
-  // Returns a specific entry.
-  virtual const ReadingListEntry& GetUnreadEntryAtIndex(size_t index) const = 0;
-  virtual const ReadingListEntry& GetReadEntryAtIndex(size_t index) const = 0;
-
   // Returns a specific entry. Returns null if the entry does not exist.
-  // If |read| is not null and the entry is found, |*read| is the read status
-  // of the entry.
-  virtual const ReadingListEntry* GetEntryFromURL(const GURL& gurl,
-                                                  bool* read) const = 0;
-
-  // Synchronously calls the |callback| with entry associated with this |url|.
-  // Does nothing if there is no entry associated.
-  // Returns whether the callback has been called.
-  virtual bool CallbackEntryURL(
-      const GURL& url,
-      base::Callback<void(const ReadingListEntry&)> callback) const = 0;
+  virtual const ReadingListEntry* GetEntryByURL(const GURL& gurl) const = 0;
 
   // Adds |url| at the top of the unread entries, and removes entries with the
   // same |url| from everywhere else if they exist. The entry title will be a
   // trimmed copy of |title.
   // The addition may be asynchronous, and the data will be available only once
   // the observers are notified.
   virtual const ReadingListEntry& AddEntry(const GURL& url,
                                            const std::string& title) = 0;
 
   // Removes an entry. The removal may be asynchronous, and not happen
   // immediately.
   virtual void RemoveEntryByURL(const GURL& url) = 0;
 
-  // If the |url| is in the reading list and unread, mark it read. If it is in
-  // the reading list and read, move it to the top of unread if it is not here
-  // already. This may trigger deletion of old read entries.
-  virtual void MarkReadByURL(const GURL& url) = 0;
-  // If the |url| is in the reading list and read, mark it unread. If it is in
-  // the reading list and unread, move it to the top of read if it is not here
-  // already.
-  virtual void MarkUnreadByURL(const GURL& url) = 0;
+  // If the |url| is in the reading list and entry(|url|).read != |read|, sets
+  // the read state of the URL to read. This will also update the update time of
+  // the entry.
+  virtual void SetReadStatus(const GURL& url, bool read) = 0;
 
   // Methods to mutate an entry. Will locate the relevant entry by URL. Does
   // nothing if the entry is not found.
   virtual void SetEntryTitle(const GURL& url, const std::string& title) = 0;
   virtual void SetEntryDistilledPath(const GURL& url,
                                      const base::FilePath& distilled_path) = 0;
   virtual void SetEntryDistilledState(
       const GURL& url,
       ReadingListEntry::DistillationState state) = 0;
 
   // Observer registration methods. The model will remove all observers upon
   // destruction automatically.
   void AddObserver(ReadingListModelObserver* observer);
   void RemoveObserver(ReadingListModelObserver* observer);
 
   // Helper class that is used to scope batch updates.
   class ScopedReadingListBatchUpdate {
    public:
     explicit ScopedReadingListBatchUpdate(ReadingListModel* model)
         : model_(model) {}
 
     virtual ~ScopedReadingListBatchUpdate();
 
    private:
     ReadingListModel* model_;
 
     DISALLOW_COPY_AND_ASSIGN(ScopedReadingListBatchUpdate);
   };
 
+  // TODO(crbug.com/664924): Remove temporary methods for transition.
+
+  // Allows iterating through read entries in the model. Must be called on a
+  // singlerunloop to ensure no entry is returned twice and all entries are
+  // returned
+  virtual const ReadingListEntry& GetReadEntryAtIndex(size_t index) const = 0;
+  virtual const ReadingListEntry& GetUnreadEntryAtIndex(size_t index) const = 0;
+  virtual void MarkReadByURL(const GURL& url) = 0;
+  virtual void MarkUnreadByURL(const GURL& url) = 0;
+  virtual size_t read_size() const = 0;
+
  protected:
   ReadingListModel();
   virtual ~ReadingListModel();
 
   // The observers.
   base::ObserverList<ReadingListModelObserver> observers_;
 
   // Tells model that batch updates have completed. Called from
   // ReadingListBatchUpdateToken dtor.
   virtual void EndBatchUpdates();
 
   // Called when model is entering batch update mode.
   virtual void EnteringBatchUpdates();
 
   // Called when model is leaving batch update mode.
   virtual void LeavingBatchUpdates();
 
  private:
   unsigned int current_batch_updates_count_;
 
   DISALLOW_COPY_AND_ASSIGN(ReadingListModel);
 };
 
 #endif  // COMPONENTS_READING_LIST_IOS_READING_LIST_MODEL_H_