ABANDONED: chromeos: Download contacts (work in progress).

chrome/browser/chromeos/contacts/contact_database.h

+// Copyright (c) 2012 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_CHROMEOS_CONTACTS_CONTACT_DATABASE_H_
+#define CHROME_BROWSER_CHROMEOS_CONTACTS_CONTACT_DATABASE_H_
+
+#include <string>
+#include <vector>
+
+#include "base/basictypes.h"
+#include "base/callback.h"
+#include "base/compiler_specific.h"
+#include "base/file_path.h"
+#include "base/memory/scoped_ptr.h"
+#include "base/memory/scoped_vector.h"
+#include "base/synchronization/condition_variable.h"
+#include "base/synchronization/lock.h"
+#include "sql/connection.h"
+#include "sql/init_status.h"
+
+namespace sql {
+class Connection;
+class MetaTable;
+}
+
+namespace contacts {
+
+struct Contact;
+typedef std::vector<const Contact*> ContactPointers;
+
+// Interface for classes providing persistent storage of Contact objects.
+class ContactDatabaseInterface {
+ public:
+  // The parameter is true on success and false on failure.
+  typedef base::Callback<void(bool)> InitCallback;
+
+  // The parameter is true on success and false on failure.
+  typedef base::Callback<void(bool)> SaveCallback;
+
+  // The first parameter is true on success and false on failure.
+  typedef base::Callback<void(bool, scoped_ptr<ScopedVector<Contact> >)>
+      LoadCallback;
+
+  ContactDatabaseInterface() {}
+  virtual ~ContactDatabaseInterface() {}
+
+  // Asynchronously initializes the object.  |callback| will be invoked on the
+  // UI thread when complete with a true parameter if initialization succeeded.
+  virtual void Init(const FilePath& database_path, InitCallback callback) = 0;
+
+  // Asynchronously saves |contacts| to the database.  |callback| will be
+  // invoked on the UI thread when complete.  The caller must not make changes
+  // to the underlying passed-in contacts until the callback has been invoked.
+  virtual void SaveContacts(scoped_ptr<ContactPointers> contacts,
+                            bool is_full_update,
+                            SaveCallback callback) = 0;
+
+  // Asynchronously loads all contacts from the database and invokes |callback|
+  // when complete.
+  virtual void LoadContacts(LoadCallback callback) = 0;
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(ContactDatabaseInterface);
+};
+
+class ContactDatabase : public ContactDatabaseInterface {
+ public:
+  ContactDatabase();
+  virtual ~ContactDatabase();
+
+  // ContactDatabaseInterface implementation.
+  virtual void Init(const FilePath& database_path,
+                    InitCallback callback) OVERRIDE;
+  virtual void SaveContacts(scoped_ptr<ContactPointers> contacts,
+                            bool is_full_update,
+                            SaveCallback callback) OVERRIDE;
+  virtual void LoadContacts(LoadCallback callback) OVERRIDE;
+
+ private:
+  // Initializes the database in |database_dir| and posts |callback| on the UI
+  // thread with the result.
+  void InitOnFileThread(const FilePath& database_path, InitCallback callback);
+
+  // Helper method called by InitOnFileThread().
+  sql::InitStatus InitInternal(const FilePath& database_path);
+
+  // Creates our set of tables in |db| if they don't already exist.
+  // Called by InitInternal().  Returns false on failure.
+  bool CreateTablesIfNeeded();
+
+  // Queries the database to find the |contact_id| field for |contact|.
+  // Returns -1 if it's not present or if an error occurs.
+  int64 GetContactId(const Contact& contact);
+
+  // Saves |contacts| to disk and invokes |callback| on the UI thread when
+  // complete.  Ownership of |contacts| remains with the caller (or with the
+  // callback itself, in this case).
+  void SaveContactsOnFileThread(scoped_ptr<ContactPointers> contacts,
+                                bool is_full_update,
+                                SaveCallback callback);
+
+  // Helper method called by SaveContactsOnFileThread().  Returns true on
+  // success.
+  bool SaveContactsInternal(const ContactPointers& contacts,
+                            bool is_full_update);
+
+  // Clears all contact-related information from the database.
+  bool ClearContacts();
+
+  // Saves |contact| to the database, returning true on success.  This method
+  // performs multiple queries, so a transaction must be open before it's
+  // called.  If |possibly_exists| is false, we don't bother checking to see if
+  // there's an existing row to update (i.e. we're doing a full update and have
+  // already cleared the tables).
+  bool SaveContact(const Contact& contact, bool possibly_exists);
+
+  // Loads contacts from disk and passes them to |callback| on the UI thread
+  // when complete.
+  void LoadContactsOnFileThread(LoadCallback callback);
+
+  // Helper method called by LoadContactsOnFileThread().  Returns true on
+  // success.
+  bool LoadContactsInternal(ScopedVector<Contact>* contacts);
+
+  // Increments or decrements |num_outstanding_file_operations_|.
+  void IncrementOutstandingFileOperations();
+  void DecrementOutstandingFileOperations();
+
+  scoped_ptr<sql::Connection> db_;
+  scoped_ptr<sql::MetaTable> meta_table_;
+
+  // Protects |num_outstanding_file_operations_|.
+  base::Lock lock_;
+
+  // Signals on |lock_| when a file operation completes.
+  base::ConditionVariable condition_variable_;
+
+  // Number of pending or in-progress operations on the file thread.
+  int num_outstanding_file_operations_;
+
+  DISALLOW_COPY_AND_ASSIGN(ContactDatabase);
+};
+
+}  // namespace contacts
+
+#endif  // CHROME_BROWSER_CHROMEOS_CONTACTS_CONTACT_DATABASE_H_