/*
 * 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;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * 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;
using System.Reflection;
using log4net;
using Nini.Config;
using OpenMetaverse;
using OpenSim.Framework;

using System.Threading;
using System.Timers;
using System.Collections.Generic;

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

namespace OpenSim.Region.CoreModules.Avatar.AvatarFactory
{
    public class AvatarFactoryModule : IAvatarFactory, IRegionModule
    {
        private static readonly ILog m_log = LogManager.GetLogger(MethodBase.GetCurrentMethod().DeclaringType);
        private Scene m_scene = null;

        private int m_savetime = 5; // seconds to wait before saving changed appearance
        private int m_sendtime = 2; // seconds to wait before sending changed appearance

        private int m_checkTime = 500; // milliseconds to wait between checks for appearance updates
        private System.Timers.Timer m_updateTimer = new System.Timers.Timer();
        private Dictionary<UUID,long> m_savequeue = new Dictionary<UUID,long>();
        private Dictionary<UUID,long> m_sendqueue = new Dictionary<UUID,long>();

        private object m_setAppearanceLock = new object();

        #region RegionModule Members

        public void Initialise(Scene scene, IConfigSource config)
        {
            scene.RegisterModuleInterface<IAvatarFactory>(this);
            scene.EventManager.OnNewClient += NewClient;

            if (config != null)
            {
                IConfig sconfig = config.Configs["Startup"];
                if (sconfig != null)
                {
                    m_savetime = Convert.ToInt32(sconfig.GetString("DelayBeforeAppearanceSave",Convert.ToString(m_savetime)));
                    m_sendtime = Convert.ToInt32(sconfig.GetString("DelayBeforeAppearanceSend",Convert.ToString(m_sendtime)));
                    // m_log.InfoFormat("[AVFACTORY] configured for {0} save and {1} send",m_savetime,m_sendtime);
                }
            }

            if (m_scene == null)
                m_scene = scene;
        }

        public void PostInitialise()
        {
            m_updateTimer.Enabled = false;
            m_updateTimer.AutoReset = true;
            m_updateTimer.Interval = m_checkTime; // 500 milliseconds wait to start async ops
            m_updateTimer.Elapsed += new ElapsedEventHandler(HandleAppearanceUpdateTimer);
        }

        public void Close()
        {
        }

        public string Name
        {
            get { return "Default Avatar Factory"; }
        }

        public bool IsSharedModule
        {
            get { return false; }
        }

        public void NewClient(IClientAPI client)
        {
            client.OnRequestWearables += SendWearables;
            client.OnSetAppearance += SetAppearance;
            client.OnAvatarNowWearing += AvatarIsWearing;
        }

        public void RemoveClient(IClientAPI client)
        {
            // client.OnAvatarNowWearing -= AvatarIsWearing;
        }

        #endregion

        /// <summary>
        /// Check for the existence of the baked texture assets. Request a rebake
        /// unless checkonly is true.
        /// </summary>
        /// <param name="client"></param>
        /// <param name="checkonly"></param>
        public bool ValidateBakedTextureCache(IClientAPI client)
        {
            return ValidateBakedTextureCache(client, true);
        }
        
        private bool ValidateBakedTextureCache(IClientAPI client, bool checkonly)
        {
            ScenePresence sp = m_scene.GetScenePresence(client.AgentId);
            if (sp == null)
            {
                m_log.WarnFormat("[AVFACTORY]: SetAppearance unable to find presence for {0}", client.AgentId);
                return false;
            }

            bool defonly = true; // are we only using default textures

            // Process the texture entry
            for (int i = 0; i < AvatarAppearance.BAKE_INDICES.Length; i++)
            {
                int idx = AvatarAppearance.BAKE_INDICES[i];
                Primitive.TextureEntryFace face = sp.Appearance.Texture.FaceTextures[idx];

                // if there is no texture entry, skip it
                if (face == null)
                    continue;

                // if the texture is one of the "defaults" then skip it
                // this should probably be more intelligent (skirt texture doesnt matter
                // if the avatar isnt wearing a skirt) but if any of the main baked 
                // textures is default then the rest should be as well
                if (face.TextureID == UUID.Zero || face.TextureID == AppearanceManager.DEFAULT_AVATAR_TEXTURE)
                    continue;
                
                defonly = false; // found a non-default texture reference

                if (! CheckBakedTextureAsset(client,face.TextureID,idx))
                {
                    // the asset didn't exist if we are only checking, then we found a bad
                    // one and we're done otherwise, ask for a rebake
                    if (checkonly) return false;

                    m_log.InfoFormat("[AVFACTORY] missing baked texture {0}, request rebake",face.TextureID);
                    client.SendRebakeAvatarTextures(face.TextureID);
                }
            }

            m_log.InfoFormat("[AVFACTORY]: complete texture check for {0}", client.AgentId);

            // If we only found default textures, then the appearance is not cached
            return (defonly ? false : true);
        }

        /// <summary>
        /// Set appearance data (textureentry and slider settings) received from the client
        /// </summary>
        /// <param name="texture"></param>
        /// <param name="visualParam"></param>
        public void SetAppearance(IClientAPI client, Primitive.TextureEntry textureEntry, byte[] visualParams)
        {
            ScenePresence sp = m_scene.GetScenePresence(client.AgentId);
            if (sp == null)
            {
                m_log.WarnFormat("[AVFACTORY]: SetAppearance unable to find presence for {0}",client.AgentId);
                return;
            }

//            m_log.InfoFormat("[AVFACTORY]: start SetAppearance for {0}", client.AgentId);

            // TODO: This is probably not necessary any longer, just assume the
            // textureEntry set implies that the appearance transaction is complete
            bool changed = false;

            // Process the texture entry transactionally, this doesn't guarantee that Appearance is
            // going to be handled correctly but it does serialize the updates to the appearance
            lock (m_setAppearanceLock)
            {
                // Process the visual params, this may change height as well
                if (visualParams != null)
                {
                    changed = sp.Appearance.SetVisualParams(visualParams);
                    if (sp.Appearance.AvatarHeight > 0)
                        sp.SetHeight(sp.Appearance.AvatarHeight);
                }

                // Process the baked texture array
                if (textureEntry != null)
                {
                    changed = sp.Appearance.SetTextureEntries(textureEntry) || changed;

                    m_log.InfoFormat("[AVFACTORY]: received texture update for {0}", client.AgentId);
                    Util.FireAndForget(delegate(object o) { ValidateBakedTextureCache(client,false); });

                    // This appears to be set only in the final stage of the appearance
                    // update transaction. In theory, we should be able to do an immediate
                    // appearance send and save here.

                    // save only if there were changes, send no matter what (doesn't hurt to send twice)
                    if (changed)
                        QueueAppearanceSave(client.AgentId);
                    QueueAppearanceSend(client.AgentId);
                }

            }

            // m_log.WarnFormat("[AVFACTORY]: complete SetAppearance for {0}:\n{1}",client.AgentId,sp.Appearance.ToString());
        }

        /// <summary>
        /// Checks for the existance of a baked texture asset and
        /// requests the viewer rebake if the asset is not found
        /// </summary>
        /// <param name="client"></param>
        /// <param name="textureID"></param>
        /// <param name="idx"></param>
        private bool CheckBakedTextureAsset(IClientAPI client, UUID textureID, int idx)
        {
            if (m_scene.AssetService.Get(textureID.ToString()) == null)
            {
                m_log.WarnFormat("[AVFACTORY]: Missing baked texture {0} ({1}) for avatar {2}",
                                 textureID, idx, client.Name);
                return false;
            }
            return true;
        }

        #region UpdateAppearanceTimer

        /// <summary>
        /// Queue up a request to send appearance, makes it possible to
        /// accumulate changes without sending out each one separately.
        /// </summary>
        public void QueueAppearanceSend(UUID agentid)
        {
            // m_log.WarnFormat("[AVFACTORY]: Queue appearance send for {0}", agentid);

            // 10000 ticks per millisecond, 1000 milliseconds per second
            long timestamp = DateTime.Now.Ticks + Convert.ToInt64(m_sendtime * 1000 * 10000);
            lock (m_sendqueue)
            {
                m_sendqueue[agentid] = timestamp;
                m_updateTimer.Start();
            }
        }

        public void QueueAppearanceSave(UUID agentid)
        {
            // m_log.WarnFormat("[AVFACTORY]: Queue appearance save for {0}", agentid);

            // 10000 ticks per millisecond, 1000 milliseconds per second
            long timestamp = DateTime.Now.Ticks + Convert.ToInt64(m_savetime * 1000 * 10000);
            lock (m_savequeue)
            {
                m_savequeue[agentid] = timestamp;
                m_updateTimer.Start();
            }
        }

        private void HandleAppearanceSend(UUID agentid)
        {
            ScenePresence sp = m_scene.GetScenePresence(agentid);
            if (sp == null)
            {
                m_log.WarnFormat("[AVFACTORY]: Agent {0} no longer in the scene", agentid);
                return;
            }

            // m_log.WarnFormat("[AVFACTORY]: Handle appearance send for {0}", agentid);

            // Send the appearance to everyone in the scene
            sp.SendAppearanceToAllOtherAgents();

            // Send animations back to the avatar as well
            sp.Animator.SendAnimPack();
        }

        private void HandleAppearanceSave(UUID agentid)
        {
            ScenePresence sp = m_scene.GetScenePresence(agentid);
            if (sp == null)
            {
                m_log.WarnFormat("[AVFACTORY]: Agent {0} no longer in the scene", agentid);
                return;
            }

            // m_log.WarnFormat("[AVFACTORY] avatar {0} save appearance",agentid);

            m_scene.AvatarService.SetAppearance(agentid, sp.Appearance);
        }

        private void HandleAppearanceUpdateTimer(object sender, EventArgs ea)
        {
            long now = DateTime.Now.Ticks;

            lock (m_sendqueue)
            {
                Dictionary<UUID, long> sends = new Dictionary<UUID, long>(m_sendqueue);
                foreach (KeyValuePair<UUID, long> kvp in sends)
                {
                    if (kvp.Value < now)
                    {
                        Util.FireAndForget(delegate(object o) { HandleAppearanceSend(kvp.Key); });
                        m_sendqueue.Remove(kvp.Key);
                    }
                }
            }

            lock (m_savequeue)
            {
                Dictionary<UUID, long> saves = new Dictionary<UUID, long>(m_savequeue);
                foreach (KeyValuePair<UUID, long> kvp in saves)
                {
                    if (kvp.Value < now)
                    {
                        Util.FireAndForget(delegate(object o) { HandleAppearanceSave(kvp.Key); });
                        m_savequeue.Remove(kvp.Key);
                    }
                }
            }

            if (m_savequeue.Count == 0 && m_sendqueue.Count == 0)
                m_updateTimer.Stop();
        }

        #endregion

        /// <summary>
        /// Tell the client for this scene presence what items it should be wearing now
        /// </summary>
        public void SendWearables(IClientAPI client)
        {
            ScenePresence sp = m_scene.GetScenePresence(client.AgentId);
            if (sp == null)
            {
                m_log.WarnFormat("[AVFACTORY]: SendWearables unable to find presence for {0}", client.AgentId);
                return;
            }

            // m_log.WarnFormat("[AVFACTORY]: Received request for wearables of {0}", client.AgentId);

            client.SendWearables(sp.Appearance.Wearables, sp.Appearance.Serial++);
        }

        /// <summary>
        /// Update what the avatar is wearing using an item from their inventory.
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        public void AvatarIsWearing(IClientAPI client, AvatarWearingArgs e)
        {
            ScenePresence sp = m_scene.GetScenePresence(client.AgentId);
            if (sp == null)
            {
                m_log.WarnFormat("[AVFACTORY]: AvatarIsWearing unable to find presence for {0}", client.AgentId);
                return;
            }

            // m_log.WarnFormat("[AVFACTORY]: AvatarIsWearing called for {0}", client.AgentId);

            // we need to clean out the existing textures
            sp.Appearance.ResetAppearance(); 

            // operate on a copy of the appearance so we don't have to lock anything
            AvatarAppearance avatAppearance = new AvatarAppearance(sp.Appearance, false);
            
            foreach (AvatarWearingArgs.Wearable wear in e.NowWearing)
            {
                if (wear.Type < AvatarWearable.MAX_WEARABLES)
                    avatAppearance.Wearables[wear.Type].Add(wear.ItemID, UUID.Zero);
            }

            avatAppearance.GetAssetsFrom(sp.Appearance);

            // This could take awhile since it needs to pull inventory
            SetAppearanceAssets(sp.UUID, ref avatAppearance);

            // could get fancier with the locks here, but in the spirit of "last write wins"
            // this should work correctly, also, we don't need to send the appearance here
            // since the "iswearing" will trigger a new set of visual param and baked texture changes
            // when those complete, the new appearance will be sent
            sp.Appearance = avatAppearance;
            QueueAppearanceSave(client.AgentId);
        }

        private void SetAppearanceAssets(UUID userID, ref AvatarAppearance appearance)
        {
            IInventoryService invService = m_scene.InventoryService;

            if (invService.GetRootFolder(userID) != null)
            {
                for (int i = 0; i < AvatarWearable.MAX_WEARABLES; i++)
                {
                    for (int j = 0; j < appearance.Wearables[j].Count; j++)
                    {
                        if (appearance.Wearables[i][j].ItemID == UUID.Zero)
                            continue;

                        // Ignore ruth's assets
                        if (appearance.Wearables[i][j].ItemID == AvatarWearable.DefaultWearables[i][0].ItemID)
                            continue;
                        InventoryItemBase baseItem = new InventoryItemBase(appearance.Wearables[i][j].ItemID, userID);
                        baseItem = invService.GetItem(baseItem);

                        if (baseItem != null)
                        {
                            appearance.Wearables[i].Add(appearance.Wearables[i][j].ItemID, baseItem.AssetID);
                        }
                        else
                        {
                            m_log.ErrorFormat(
                                "[AVFACTORY]: Can't find inventory item {0} for {1}, setting to default",
                                appearance.Wearables[i][j].ItemID, (WearableType)i);

                            appearance.Wearables[i].RemoveItem(appearance.Wearables[i][j].ItemID);
                        }
                    }
                }
            }
            else
            {
                m_log.WarnFormat("[AVFACTORY]: user {0} has no inventory, appearance isn't going to work", userID);
            }
        }
    }
}