text: // Copyright 2013 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 EXTENSIONS_COMMON_PERMISSIONS_PERMISSION_MESSAGE_PROVIDER_H_
  #define EXTENSIONS_COMMON_PERMISSIONS_PERMISSION_MESSAGE_PROVIDER_H_
  
  #include <vector>
  
  #include "extensions/common/manifest.h"
  #include "extensions/common/permissions/permission_message.h"
  
  namespace extensions {
  
  class PermissionIDSet;
  class PermissionSet;
  
  // The PermissionMessageProvider interprets permissions, translating them
  // into warning messages to show to the user. It also determines whether
  // a new set of permissions entails showing new warning messages.
  class PermissionMessageProvider {
   public:
    PermissionMessageProvider() {}
    virtual ~PermissionMessageProvider() {}
  
    // Return the global permission message provider.
    static const PermissionMessageProvider* Get();
  
    // Calculates and returns the full list of permission messages for the given
    // |permissions|. This involves converting the given PermissionIDs into
    // localized messages, as well as coalescing and parameterizing any messages
    // that require the permission ID's argument in their message.
    virtual PermissionMessages GetPermissionMessages(
        const PermissionIDSet& permissions) const = 0;
  
    // Returns true if |requested_permissions| has a greater privilege level than
    // |granted_permissions|.
    // Whether certain permissions are considered varies by extension type.
    // TODO(sashab): Add an implementation of this method that uses
    // PermissionIDSet instead, then deprecate this one.
    virtual bool IsPrivilegeIncrease(const PermissionSet& granted_permissions,
                                     const PermissionSet& requested_permissions,
                                     Manifest::Type extension_type) const = 0;
  
    // Given the permissions for an extension, finds the IDs of all the
    // permissions for that extension (including API, manifest and host
    // permissions).
    // TODO(sashab): This uses the legacy PermissionSet type. Deprecate or rename
    // this type, and make this take as little as is needed to work out the
    // PermissionIDSet.
    virtual PermissionIDSet GetAllPermissionIDs(
        const PermissionSet& permissions,
        Manifest::Type extension_type) const = 0;
  };
  
  }  // namespace extensions
  
  #endif  // EXTENSIONS_COMMON_PERMISSIONS_PERMISSION_MESSAGE_PROVIDER_H_
  