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using OpenMetaverse;
using OpenSim.Framework;
using OpenSim.Region.Framework.Scenes;

namespace OpenSim.Region.Framework.Interfaces
{
    /// <summary>
    /// Temporary interface.  More methods to come at some point to make NPCs more object oriented rather than
    /// controlling purely through module level interface calls (e.g. sit/stand).
    /// </summary>
    public interface INPC
    {
        /// <summary>
        /// Should this NPC be sensed by LSL sensors as an 'agent' (interpreted here to mean a normal user)
        /// rather than an OpenSim specific NPC extension?
        /// </summary>
        bool SenseAsAgent { get; }
    }

    public interface INPCModule
    {
        /// <summary>
        /// Create an NPC
        /// </summary>
        /// <param name="firstname"></param>
        /// <param name="lastname"></param>
        /// <param name="position"></param>
        /// <param name="senseAsAgent">
        /// Make the NPC show up as an agent on LSL sensors.  The default is that they
        /// show up as the NPC type instead, but this is currently an OpenSim-only extension.
        /// </param>
        /// <param name="scene"></param>
        /// <param name="appearance">The avatar appearance to use for the new NPC.</param>
        /// <returns>The UUID of the ScenePresence created.  UUID.Zero if there was a failure.</returns>
        UUID CreateNPC(
            string firstname,
            string lastname,
            Vector3 position,
            UUID owner,
            bool senseAsAgent,
            Scene scene,
            AvatarAppearance appearance);

        /// <summary>
        /// Check if the agent is an NPC.
        /// </summary>
        /// <param name="agentID"></param>
        /// <param name="scene"></param>
        /// <returns>True if the agent is an NPC in the given scene.  False otherwise.</returns>
        bool IsNPC(UUID agentID, Scene scene);

        /// <summary>
        /// Get the NPC.  This is not currently complete - manipulation of NPCs still occurs through the region interface
        /// </summary>
        /// <param name="agentID"></param>
        /// <param name="scene"></param>
        /// <returns>The NPC.  null if it does not exist.</returns>
        INPC GetNPC(UUID agentID, Scene scene);

        /// <summary>
        /// Check if the caller has permission to manipulate the given NPC.
        /// </summary>
        /// <param name="npcID"></param>
        /// <param name="callerID"></param>
        /// <returns>true if they do, false if they don't or if there's no NPC with the given ID.</returns>
        bool CheckPermissions(UUID npcID, UUID callerID);

        /// <summary>
        /// Set the appearance for an NPC.
        /// </summary>
        /// <param name="agentID"></param>
        /// <param name="appearance"></param>
        /// <param name="scene"></param>
        /// <returns>True if the operation succeeded, false if there was no such agent or the agent was not an NPC</returns>
        bool SetNPCAppearance(UUID agentID, AvatarAppearance appearance, Scene scene);

        /// <summary>
        /// Move an NPC to a target over time.
        /// </summary>
        /// <param name="agentID">The UUID of the NPC</param>
        /// <param name="scene"></param>
        /// <param name="pos"></param>
        /// <param name="noFly">
        /// If true, then the avatar will attempt to walk to the location even if it's up in the air.
        /// This is to allow walking on prims.
        /// </param>
        /// <param name="landAtTarget">
        /// If true and the avatar is flying when it reaches the target, land.
        /// </param>
        /// <returns>True if the operation succeeded, false if there was no such agent or the agent was not an NPC</returns>
        bool MoveToTarget(UUID agentID, Scene scene, Vector3 pos, bool noFly, bool landAtTarget);

        /// <summary>
        /// Stop the NPC's current movement.
        /// </summary>
        /// <param name="agentID">The UUID of the NPC</param>
        /// <param name="scene"></param>
        /// <returns>True if the operation succeeded, false if there was no such agent or the agent was not an NPC</returns>
        bool StopMoveToTarget(UUID agentID, Scene scene);

        /// <summary>
        /// Get the NPC to say something.
        /// </summary>
        /// <param name="agentID">The UUID of the NPC</param>
        /// <param name="scene"></param>
        /// <param name="text"></param>
        /// <returns>True if the operation succeeded, false if there was no such agent or the agent was not an NPC</returns>
        bool Say(UUID agentID, Scene scene, string text);

        /// <summary>
        /// Sit the NPC.
        /// </summary>
        /// <param name="agentID"></param>
        /// <param name="partID"></param>
        /// <param name="scene"></param>
        /// <returns>true if the sit succeeded, false if not</returns>
        bool Sit(UUID agentID, UUID partID, Scene scene);

        /// <summary>
        /// Stand a sitting NPC.
        /// </summary>
        /// <param name="agentID"></param>
        /// <param name="scene"></param>
        /// <returns>true if the stand succeeded, false if not</returns>
        bool Stand(UUID agentID, Scene scene);

        /// <summary>
        /// Delete an NPC.
        /// </summary>
        /// <param name="agentID">The UUID of the NPC</param>
        /// <param name="scene"></param>
        /// <returns>True if the operation succeeded, false if there was no such agent or the agent was not an NPC</returns>
        bool DeleteNPC(UUID agentID, Scene scene);

        /// <summary>
        /// Get the owner of a NPC
        /// </summary>
        /// <param name="agentID">The UUID of the NPC</param>
        /// <returns>UUID of owner if the NPC exists, UUID.Zero  if there was no such agent, the agent is unowned  or the agent was not an NPC</returns>
        UUID GetOwner(UUID agentID);
    }
}