OpenSim-Test/OpenSim/Region/Environment/Modules/World/Archiver/AssetsRequest.cs

/*
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 * THIS SOFTWARE IS PROVIDED BY THE DEVELOPERS ``AS IS'' AND ANY
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using OpenSim.Framework;
using OpenSim.Framework.Communications.Cache;
using OpenSim.Region.Environment.Interfaces;
using OpenSim.Region.Environment.Scenes;
using System.Collections.Generic;
using System.Threading;
using libsecondlife;

namespace OpenSim.Region.Environment.Modules.World.Archiver
{
    /// <summary>
    /// Encapsulate the asynchronous requests for the assets required for an archive operation
    /// </summary>
    class AssetsRequest
    {
        /// <summary>
        /// uuids to request
        /// </summary>
        protected ICollection<LLUUID> m_uuids;
        
        /// <summary>
        /// Callback used when all the assets requested have been received.
        /// </summary>
        protected AssetsRequestCallback m_assetsRequestCallback;

        /// <summary>
        /// Assets retrieved in this request
        /// </summary>
        protected Dictionary<LLUUID, AssetBase> m_assets = new Dictionary<LLUUID, AssetBase>();

        /// <summary>
        /// Record the number of asset replies required so we know when we've finished
        /// </summary>
        private int m_repliesRequired;

        /// <summary>
        /// Asset cache used to request the assets
        /// </summary>
        protected AssetCache m_assetCache;

        protected internal AssetsRequest(ICollection<LLUUID> uuids, AssetCache assetCache, AssetsRequestCallback assetsRequestCallback)
        {
            m_uuids = uuids;
            m_assetsRequestCallback = assetsRequestCallback;
            m_assetCache = assetCache;
            m_repliesRequired = uuids.Count;
        }
        
        protected internal void Execute()
        {
            // We can stop here if there are no assets to fetch
            if (m_repliesRequired == 0)
                m_assetsRequestCallback(m_assets);

            foreach (LLUUID uuid in m_uuids)
            {
                m_assetCache.GetAsset(uuid, AssetRequestCallback, true);
            }
        }

        /// <summary>
        /// Called back by the asset cache when it has the asset
        /// </summary>
        /// <param name="assetID"></param>
        /// <param name="asset"></param>
        public void AssetRequestCallback(LLUUID assetID, AssetBase asset)
        {
            m_assets[assetID] = asset;

            if (m_assets.Count == m_repliesRequired)
            {
                // We want to stop using the asset cache thread asap as we now need to do the actual work of producing the archive
                Thread newThread = new Thread(PerformAssetsRequestCallback);
                newThread.Name = "OpenSimulator archiving thread post assets receipt";
                newThread.Start();
            }
        }

        /// <summary>
        /// Perform the callback on the original requester of the assets
        /// </summary>
        protected void PerformAssetsRequestCallback()
        {
            m_assetsRequestCallback(m_assets);
        }
    }
}