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 * See CONTRIBUTORS.TXT for a full list of copyright holders.
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 * modification, are permitted provided that the following conditions are met:
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 *       notice, this list of conditions and the following disclaimer.
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 *       notice, this list of conditions and the following disclaimer in the
 *       documentation and/or other materials provided with the distribution.
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 *       names of its contributors may be used to endorse or promote products
 *       derived from this software without specific prior written permission.
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 * THIS SOFTWARE IS PROVIDED BY THE DEVELOPERS ``AS IS'' AND ANY
 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
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using System;
using System.Collections.Generic;
using System.IO;
using System.IO.Compression;
using System.Reflection;
using System.Xml;
using log4net;
using OpenMetaverse;
using OpenSim.Framework;
using OpenSim.Framework.Serialization;
using OpenSim.Framework.Serialization.External;
using OpenSim.Framework.Communications;
using OpenSim.Framework.Communications.Osp;
using OpenSim.Region.CoreModules.World.Archiver;
using OpenSim.Region.Framework.Scenes;
using OpenSim.Services.Interfaces;

namespace OpenSim.Region.CoreModules.Avatar.Inventory.Archiver
{
    public class InventoryArchiveWriteRequest
    {
        private static readonly ILog m_log = LogManager.GetLogger(MethodBase.GetCurrentMethod().DeclaringType);

        /// <value>
        /// Used to select all inventory nodes in a folder but not the folder itself
        /// </value>
        private const string STAR_WILDCARD = "*";

        private InventoryArchiverModule m_module;
        private UserAccount m_userInfo;
        private string m_invPath;
        protected TarArchiveWriter m_archiveWriter;
        protected UuidGatherer m_assetGatherer;

        /// <value>
        /// We only use this to request modules
        /// </value>
        protected Scene m_scene;

        /// <value>
        /// ID of this request
        /// </value>
        protected Guid m_id;

        /// <value>
        /// Used to collect the uuids of the assets that we need to save into the archive
        /// </value>
        protected Dictionary<UUID, AssetType> m_assetUuids = new Dictionary<UUID, AssetType>();

        /// <value>
        /// Used to collect the uuids of the users that we need to save into the archive
        /// </value>
        protected Dictionary<UUID, int> m_userUuids = new Dictionary<UUID, int>();

        /// <value>
        /// The stream to which the inventory archive will be saved.
        /// </value>
        private Stream m_saveStream;

        /// <summary>
        /// Constructor
        /// </summary>
        public InventoryArchiveWriteRequest(
            Guid id, InventoryArchiverModule module, Scene scene, 
            UserAccount userInfo, string invPath, string savePath)
            : this(
                id,
                module,
                scene,
                userInfo,
                invPath,
                new GZipStream(new FileStream(savePath, FileMode.Create), CompressionMode.Compress))
        {
        }

        /// <summary>
        /// Constructor
        /// </summary>
        public InventoryArchiveWriteRequest(
            Guid id, InventoryArchiverModule module, Scene scene, 
            UserAccount userInfo, string invPath, Stream saveStream)
        {
            m_id = id;
            m_module = module;
            m_scene = scene;
            m_userInfo = userInfo;
            m_invPath = invPath;
            m_saveStream = saveStream;
            m_assetGatherer = new UuidGatherer(m_scene.AssetService);
        }

        protected void ReceivedAllAssets(ICollection<UUID> assetsFoundUuids, ICollection<UUID> assetsNotFoundUuids)
        {
            Exception reportedException = null;
            bool succeeded = true;
            
            try
            {
                // We're almost done.  Just need to write out the control file now
                m_archiveWriter.WriteFile(ArchiveConstants.CONTROL_FILE_PATH, Create0p1ControlFile());
                m_log.InfoFormat("[ARCHIVER]: Added control file to archive.");

                m_archiveWriter.Close();
            }
            catch (Exception e)
            {
                m_saveStream.Close();
                reportedException = e;
                succeeded = false;
            }

            m_module.TriggerInventoryArchiveSaved(
                m_id, succeeded, m_userInfo, m_invPath, m_saveStream, reportedException);
        }

        protected void SaveInvItem(InventoryItemBase inventoryItem, string path)
        {
            string filename = path + CreateArchiveItemName(inventoryItem);

            // Record the creator of this item for user record purposes (which might go away soon)
            m_userUuids[inventoryItem.CreatorIdAsUuid] = 1;

            InventoryItemBase saveItem = (InventoryItemBase)inventoryItem.Clone();
            saveItem.CreatorId = OspResolver.MakeOspa(saveItem.CreatorIdAsUuid, m_scene.UserAccountService);

            string serialization = UserInventoryItemSerializer.Serialize(saveItem);
            m_archiveWriter.WriteFile(filename, serialization);

            m_assetGatherer.GatherAssetUuids(saveItem.AssetID, (AssetType)saveItem.AssetType, m_assetUuids);
        }

        /// <summary>
        /// Save an inventory folder
        /// </summary>
        /// <param name="inventoryFolder">The inventory folder to save</param>
        /// <param name="path">The path to which the folder should be saved</param>
        /// <param name="saveThisFolderItself">If true, save this folder itself.  If false, only saves contents</param>
        protected void SaveInvFolder(InventoryFolderBase inventoryFolder, string path, bool saveThisFolderItself)
        {
            if (saveThisFolderItself)
            {
                path += CreateArchiveFolderName(inventoryFolder);

                // We need to make sure that we record empty folders
                m_archiveWriter.WriteDir(path);
            }

            InventoryCollection contents 
                = m_scene.InventoryService.GetFolderContent(inventoryFolder.Owner, inventoryFolder.ID);
            //List<InventoryFolderImpl> childFolders = inventoryFolder.RequestListOfFolderImpls();
            //List<InventoryItemBase> items = inventoryFolder.RequestListOfItems();

            /*
            Dictionary identicalFolderNames = new Dictionary<string, int>();

            foreach (InventoryFolderImpl folder in inventories)
            {
                if (!identicalFolderNames.ContainsKey(folder.Name))
                    identicalFolderNames[folder.Name] = 0;
                else
                    identicalFolderNames[folder.Name] = identicalFolderNames[folder.Name]++;

                int folderNameNumber = identicalFolderName[folder.Name];

                SaveInvDir(
                    folder,
                    string.Format(
                        "{0}{1}{2}/",
                        path, ArchiveConstants.INVENTORY_NODE_NAME_COMPONENT_SEPARATOR, folderNameNumber));
            }
            */

            foreach (InventoryFolderBase childFolder in contents.Folders)
            {
                SaveInvFolder(childFolder, path, true);
            }

            foreach (InventoryItemBase item in contents.Items)
            {
                SaveInvItem(item, path);
            }
        }

        /// <summary>
        /// Execute the inventory write request
        /// </summary>
        public void Execute()
        {
            InventoryFolderBase inventoryFolder = null;
            InventoryItemBase inventoryItem = null;
            InventoryFolderBase rootFolder = m_scene.InventoryService.GetRootFolder(m_userInfo.PrincipalID);

            bool foundStar = false;

            // Eliminate double slashes and any leading / on the path.
            string[] components
                = m_invPath.Split(
                    new string[] { InventoryFolderImpl.PATH_DELIMITER }, StringSplitOptions.RemoveEmptyEntries);

            int maxComponentIndex = components.Length - 1;

            // If the path terminates with a STAR then later on we want to archive all nodes in the folder but not the
            // folder itself.  This may get more sophisicated later on
            if (maxComponentIndex >= 0 && components[maxComponentIndex] == STAR_WILDCARD)
            {
                foundStar = true;
                maxComponentIndex--;
            }

            m_invPath = String.Empty;
            for (int i = 0; i <= maxComponentIndex; i++)
            {
                m_invPath += components[i] + InventoryFolderImpl.PATH_DELIMITER;
            }

            // Annoyingly Split actually returns the original string if the input string consists only of delimiters
            // Therefore if we still start with a / after the split, then we need the root folder
            if (m_invPath.Length == 0)
            {
                inventoryFolder = rootFolder;
            }
            else
            {
                m_invPath = m_invPath.Remove(m_invPath.LastIndexOf(InventoryFolderImpl.PATH_DELIMITER));
                List<InventoryFolderBase> candidateFolders 
                    = InventoryArchiveUtils.FindFolderByPath(m_scene.InventoryService, rootFolder, m_invPath);
                if (candidateFolders.Count > 0)
                    inventoryFolder = candidateFolders[0];
            }

            // The path may point to an item instead
            if (inventoryFolder == null)
            {
                inventoryItem = InventoryArchiveUtils.FindItemByPath(m_scene.InventoryService, rootFolder, m_invPath);
                //inventoryItem = m_userInfo.RootFolder.FindItemByPath(m_invPath);
            }

            if (null == inventoryFolder && null == inventoryItem)
            {
                // We couldn't find the path indicated 
                string errorMessage = string.Format("Aborted save.  Could not find inventory path {0}", m_invPath);
                m_log.ErrorFormat("[INVENTORY ARCHIVER]: {0}", errorMessage);
                m_module.TriggerInventoryArchiveSaved(
                    m_id, false, m_userInfo, m_invPath, m_saveStream,
                    new Exception(errorMessage));
                return;
            }
            
            m_archiveWriter = new TarArchiveWriter(m_saveStream);

            try
            {
                if (inventoryFolder != null)
                {
                    m_log.DebugFormat(
                        "[INVENTORY ARCHIVER]: Found folder {0} {1} at {2}",
                        inventoryFolder.Name, inventoryFolder.ID, m_invPath);
    
                    //recurse through all dirs getting dirs and files
                    SaveInvFolder(inventoryFolder, ArchiveConstants.INVENTORY_PATH, !foundStar);
                }
                else if (inventoryItem != null)
                {
                    m_log.DebugFormat(
                        "[INVENTORY ARCHIVER]: Found item {0} {1} at {2}",
                        inventoryItem.Name, inventoryItem.ID, m_invPath);
    
                    SaveInvItem(inventoryItem, ArchiveConstants.INVENTORY_PATH);
                }
            
                // Don't put all this profile information into the archive right now.
                //SaveUsers();
            }
            catch (Exception)
            {
                m_archiveWriter.Close();
                throw;
            }
            
            new AssetsRequest(
                new AssetsArchiver(m_archiveWriter), m_assetUuids, 
                m_scene.AssetService, ReceivedAllAssets).Execute();
        }

        /// <summary>
        /// Save information for the users that we've collected.
        /// </summary>
        protected void SaveUsers()
        {
            m_log.InfoFormat("[INVENTORY ARCHIVER]: Saving user information for {0} users", m_userUuids.Count);

            foreach (UUID creatorId in m_userUuids.Keys)
            {
                // Record the creator of this item
                UserAccount creator = m_scene.UserAccountService.GetUserAccount(m_scene.RegionInfo.ScopeID, creatorId);

                if (creator != null)
                {
                    m_archiveWriter.WriteFile(
                        ArchiveConstants.USERS_PATH + creator.FirstName + " " + creator.LastName + ".xml",
                        UserProfileSerializer.Serialize(creator.PrincipalID, creator.FirstName, creator.LastName));
                }
                else
                {
                    m_log.WarnFormat("[INVENTORY ARCHIVER]: Failed to get creator profile for {0}", creatorId);
                }
            }
        }

        /// <summary>
        /// Create the archive name for a particular folder.
        /// </summary>
        ///
        /// These names are prepended with an inventory folder's UUID so that more than one folder can have the
        /// same name
        /// 
        /// <param name="folder"></param>
        /// <returns></returns>
        public static string CreateArchiveFolderName(InventoryFolderBase folder)
        {
            return CreateArchiveFolderName(folder.Name, folder.ID);
        }

        /// <summary>
        /// Create the archive name for a particular item.
        /// </summary>
        ///
        /// These names are prepended with an inventory item's UUID so that more than one item can have the
        /// same name
        /// 
        /// <param name="item"></param>
        /// <returns></returns>
        public static string CreateArchiveItemName(InventoryItemBase item)
        {
            return CreateArchiveItemName(item.Name, item.ID);
        }

        /// <summary>
        /// Create an archive folder name given its constituent components
        /// </summary>
        /// <param name="name"></param>
        /// <param name="id"></param>
        /// <returns></returns>
        public static string CreateArchiveFolderName(string name, UUID id)
        {
            return string.Format(
                "{0}{1}{2}/",
                InventoryArchiveUtils.EscapeArchivePath(name),
                ArchiveConstants.INVENTORY_NODE_NAME_COMPONENT_SEPARATOR,
                id);
        }

        /// <summary>
        /// Create an archive item name given its constituent components
        /// </summary>
        /// <param name="name"></param>
        /// <param name="id"></param>
        /// <returns></returns>
        public static string CreateArchiveItemName(string name, UUID id)
        {
            return string.Format(
                "{0}{1}{2}.xml",
                InventoryArchiveUtils.EscapeArchivePath(name),
                ArchiveConstants.INVENTORY_NODE_NAME_COMPONENT_SEPARATOR,
                id);
        }

        /// <summary>
        /// Create the control file for a 0.1 version archive
        /// </summary>
        /// <returns></returns>
        public static string Create0p1ControlFile()
        {
            StringWriter sw = new StringWriter();
            XmlTextWriter xtw = new XmlTextWriter(sw);
            xtw.Formatting = Formatting.Indented;
            xtw.WriteStartDocument();
            xtw.WriteStartElement("archive");
            xtw.WriteAttributeString("major_version", "0");
            xtw.WriteAttributeString("minor_version", "1");
            xtw.WriteEndElement();

            xtw.Flush();
            xtw.Close();

            String s = sw.ToString();
            sw.Close();

            return s;
        }
    }
}