// Copyright 2015 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_SESSIONS_CORE_LIVE_TAB_H_
#define COMPONENTS_SESSIONS_CORE_LIVE_TAB_H_

#include "components/sessions/core/serialized_navigation_entry.h"
#include "components/sessions/core/sessions_export.h"
#include "components/sessions/core/tab_restore_service.h"

namespace sessions {

// Interface that represents a currently-live tab to the core sessions code, and
// in particular, the tab restore service. This interface abstracts the concrete
// representation of a live tab on different platforms (e.g., WebContents on
// //content-based platforms).
class SESSIONS_EXPORT LiveTab {
 public:
  virtual ~LiveTab();

  // Methods that return information about the navigation state of the tab.
  virtual bool IsInitialBlankNavigation() = 0;
  virtual int GetCurrentEntryIndex() = 0;
  virtual int GetPendingEntryIndex() = 0;
  virtual SerializedNavigationEntry GetEntryAtIndex(int index) = 0;
  virtual SerializedNavigationEntry GetPendingEntry() = 0;
  virtual int GetEntryCount() = 0;

  // Returns any platform-specific data that should be associated with the
  // TabRestoreService::Tab corresponding to this instance. The default
  // implementation returns null.
  virtual scoped_ptr<PlatformSpecificTabData> GetPlatformSpecificTabData();

  // Loads the current page if necessary (where "necessary" is defined on a
  // platform-specific basis).
  virtual void LoadIfNecessary() = 0;

  // Returns the user agent override, if any.
  virtual const std::string& GetUserAgentOverride() const = 0;
};

}  // namespace sessions

#endif  // COMPONENTS_SESSIONS_CORE_LIVE_TAB_H_