/*
 * Copyright (c) Contributors, http://opensimulator.org/
 * See CONTRIBUTORS.TXT for a full list of copyright holders.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *     * Redistributions of source code must retain the above copyright
 *       notice, this list of conditions and the following disclaimer.
 *     * Redistributions in binary form must reproduce the above copyright
 *       notice, this list of conditions and the following disclaimer in the
 *       documentation and/or other materials provided with the distribution.
 *     * Neither the name of the OpenSimulator Project nor the
 *       names of its contributors may be used to endorse or promote products
 *       derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE DEVELOPERS ``AS IS'' AND ANY
 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL THE CONTRIBUTORS BE LIABLE FOR ANY
 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
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 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

using System.Collections.Generic;
using System.Reflection;
using log4net;
using OpenMetaverse;
using OpenSim.Framework;

using OpenSim.Region.Framework.Scenes;
using OpenSim.Services.Interfaces;

namespace OpenSim.Region.CoreModules.Agent.AssetTransaction
{
    /// <summary>
    /// Manage asset transactions for a single agent.
    /// </summary>
    public class AgentAssetTransactions
    {
        private static readonly ILog m_log = LogManager.GetLogger(MethodBase.GetCurrentMethod().DeclaringType);

        // Fields
        private bool m_dumpAssetsToFile;
        private Scene m_Scene;
        private Dictionary<UUID, AssetXferUploader> XferUploaders = new Dictionary<UUID, AssetXferUploader>();

        // Methods
        public AgentAssetTransactions(UUID agentID, Scene scene,
                bool dumpAssetsToFile)
        {
            m_Scene = scene;
            m_dumpAssetsToFile = dumpAssetsToFile;
        }

        /// <summary>
        /// Return a xfer uploader if one does not already exist.
        /// </summary>
        /// <param name="transactionID"></param>
        /// <param name="assetID">
        /// We must transfer the new asset ID into the uploader on creation, otherwise
        /// we can see race conditions with other threads which can retrieve an item before it is updated with the new
        /// asset id.
        /// </param>
        /// <returns>
        /// The xfer uploader requested.  Null if one is already in existence.
        /// FIXME: This is a bizarre thing to do, and is probably meant to signal an error condition if multiple
        /// transfers are made.  Needs to be corrected.
        /// </returns>
        public AssetXferUploader RequestXferUploader(UUID transactionID, UUID assetID)
        {
            lock (XferUploaders)
            {
                if (!XferUploaders.ContainsKey(transactionID))
                {
                    AssetXferUploader uploader = new AssetXferUploader(this, m_Scene, assetID, m_dumpAssetsToFile);

//                    m_log.DebugFormat(
//                        "[AGENT ASSETS TRANSACTIONS]: Adding asset xfer uploader {0} since it didn't previously exist", transactionID);

                    XferUploaders.Add(transactionID, uploader);

                    return uploader;
                }
            }

            m_log.WarnFormat("[AGENT ASSETS TRANSACTIONS]: Ignoring request for asset xfer uploader {0} since it already exists", transactionID);

            return null;
        }

        public void HandleXfer(ulong xferID, uint packetID, byte[] data)
        {
            AssetXferUploader foundUploader = null;

            lock (XferUploaders)
            {
                foreach (AssetXferUploader uploader in XferUploaders.Values)
                {
//                    m_log.DebugFormat(
//                        "[AGENT ASSETS TRANSACTIONS]: In HandleXfer, inspect xfer upload with xfer id {0}",
//                        uploader.XferID);

                    if (uploader.XferID == xferID)
                    {
                        foundUploader = uploader;
                        break;
                    }
                }
            }

            if (foundUploader != null)
            {
//                m_log.DebugFormat(
//                    "[AGENT ASSETS TRANSACTIONS]: Found xfer uploader for xfer id {0}, packet id {1}, data length {2}",
//                    xferID, packetID, data.Length);

                foundUploader.HandleXferPacket(xferID, packetID, data);
            }
            else
            {
                m_log.ErrorFormat(
                    "[AGENT ASSET TRANSACTIONS]: Could not find uploader for xfer id {0}, packet id {1}, data length {2}",
                    xferID, packetID, data.Length);
            }
        }

        public bool RemoveXferUploader(UUID transactionID)
        {
            lock (XferUploaders)
            {
                bool removed = XferUploaders.Remove(transactionID);

                if (!removed)
                    m_log.WarnFormat(
                        "[AGENT ASSET TRANSACTIONS]: Received request to remove xfer uploader with transaction ID {0} but none found",
                        transactionID);
//                else
//                    m_log.DebugFormat(
//                        "[AGENT ASSET TRANSACTIONS]: Removed xfer uploader with transaction ID {0}", transactionID);

                return removed;
            }
        }

        public bool RequestCreateInventoryItem(IClientAPI remoteClient,
                UUID transactionID, UUID folderID, uint callbackID,
                string description, string name, sbyte invType,
               sbyte type, byte wearableType, uint nextOwnerMask)
        {
            AssetXferUploader uploader = null;

            lock (XferUploaders)
            {
                if (XferUploaders.ContainsKey(transactionID))
                    uploader = XferUploaders[transactionID];
            }

            if (uploader != null)
            {
                uploader.RequestCreateInventoryItem(
                    remoteClient, transactionID, folderID,
                    callbackID, description, name, invType, type,
                    wearableType, nextOwnerMask);

                return true;
            }
            
            return false;
        }

        /// <summary>
        /// Get an uploaded asset. If the data is successfully retrieved,
        /// the transaction will be removed.
        /// </summary>
        /// <param name="transactionID"></param>
        /// <returns>The asset if the upload has completed, null if it has not.</returns>
        private AssetBase GetTransactionAsset(UUID transactionID)
        {
            lock (XferUploaders)
            {
                if (XferUploaders.ContainsKey(transactionID))
                {
                    AssetXferUploader uploader = XferUploaders[transactionID];
                    AssetBase asset = uploader.GetAssetData();
                    RemoveXferUploader(transactionID);

                    return asset;
                }
            }

            return null;
        }

        public void RequestUpdateTaskInventoryItem(IClientAPI remoteClient,
                SceneObjectPart part, UUID transactionID,
                TaskInventoryItem item)
        {
            AssetXferUploader uploader = null;

            lock (XferUploaders)
            {
                if (XferUploaders.ContainsKey(transactionID))
                    uploader = XferUploaders[transactionID];
            }

            if (uploader != null)
            {
                AssetBase asset = GetTransactionAsset(transactionID);

                // Only legacy viewers use this, and they prefer CAPS, which 
                // we have, so this really never runs.
                // Allow it, but only for "safe" types.
                if ((InventoryType)item.InvType != InventoryType.Notecard &&
                    (InventoryType)item.InvType != InventoryType.LSL)
                    return;

                if (asset != null)
                {
//                    m_log.DebugFormat(
//                        "[AGENT ASSETS TRANSACTIONS]: Updating item {0} in {1} for transaction {2}", 
//                        item.Name, part.Name, transactionID);
                    
                    asset.FullID = UUID.Random();
                    asset.Name = item.Name;
                    asset.Description = item.Description;
                    asset.Type = (sbyte)item.Type;
                    item.AssetID = asset.FullID;

                    m_Scene.AssetService.Store(asset);
                }
            }
            else
            {
                m_log.ErrorFormat(
                    "[AGENT ASSET TRANSACTIONS]: Could not find uploader with transaction ID {0} when handling request to update task inventory item {1} in {2}",
                    transactionID, item.Name, part.Name);
            }
        }

        public void RequestUpdateInventoryItem(IClientAPI remoteClient,
                UUID transactionID, InventoryItemBase item)
        {
            AssetXferUploader uploader = null;

            lock (XferUploaders)
            {
                if (XferUploaders.ContainsKey(transactionID))
                    uploader = XferUploaders[transactionID];
            }

            if (uploader != null)
            {
                uploader.RequestUpdateInventoryItem(remoteClient, transactionID, item);
            }
            else
            {
                m_log.ErrorFormat(
                    "[AGENT ASSET TRANSACTIONS]: Could not find uploader with transaction ID {0} when handling request to update inventory item {1} for {2}",
                    transactionID, item.Name, remoteClient.Name);
            }
        }
    }
}