using UnityEditor;
using UnityEngine;
using System;
using System.Threading;
using System.Collections;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Linq;
using System.Text;
using Perforce.P4;
using log4net;

namespace P4Connect
{
    /// <summary>
    /// Simple asset status class
    /// Stores the file state (checked out, modified, etc...) and revision state
    /// </summary>

    public class AssetStatus
    {
        public enum LastUpdateType
        {
            OnServer,
            OffServer,
            Default
        }
        
        public DateTime TimeStamp;
        public FileState LocalState;
        public FileState OtherState;
        public DepotState DepotState;
        public RevisionState RevisionState;
        public ResolvedState ResolvedState;
        public StorageType StorageType;
        public LockState LockState;
        public LastUpdateType UpdateType;
        

        private static readonly GUILayoutOption _nameWidth = GUILayout.Width(100);
        private static GUILayoutOption _valueWidth = GUILayout.Width(120);

        // Use this to create an AssetStatus for a local file (perforce would return null from the fstat call)
        public AssetStatus()
        {
            TimeStamp = default(DateTime);
            
            LocalState = FileState.None;
            OtherState = FileState.None;
            DepotState = DepotState.None;
            RevisionState = P4Connect.RevisionState.None;
            ResolvedState = P4Connect.ResolvedState.None;
            StorageType = StorageType.Text;
            LockState = LockState.None;
            UpdateType = LastUpdateType.Default;
        }

        public override string ToString()
        {
            StringBuilder sb = new StringBuilder();
            if (TimeStamp == default(DateTime))
            {
                sb.AppendFormat("Dummy AssetStatus");
            }
            else
            {
                sb.AppendFormat("TimeStamp: {0} ", TimeStamp);
                sb.AppendFormat("UpdateType: {0} ", UpdateType);
                sb.AppendFormat("LocalState: {0} ", LocalState);
                sb.AppendFormat("OtherState: {0} ", OtherState);
                sb.AppendFormat("DepotState: {0} ", DepotState);
                sb.AppendFormat("Revision: {0} ", RevisionState);
                sb.AppendFormat("Resolved: {0} ", ResolvedState);
                sb.AppendFormat("Storage: {0} ", StorageType);
                sb.AppendFormat("Lockstate: {0} ", LockState);
            }
            return (sb.ToString());
        }

        public bool IsOnServer()
        {
            return (LocalState != FileState.None && LocalState != FileState.MarkedForAdd);
        }

        public bool IsAddable()
        {
            return (LocalState == FileState.None ||
                    (LocalState == FileState.InDepot && DepotState == DepotState.Deleted));
        }

        public bool IsEditable()
        {
            return (LocalState == FileState.InDepot && (DepotState != DepotState.Deleted));
        }

        public bool IsLocked()
        {
            return (LockState == LockState.OurLock || LockState == LockState.TheirLock);
        }

        public bool IsLockable()
        {
            return (LockState != LockState.TheirLock && IsOpened() && !IsLocked());
        }

        public bool IsUnlockable()
        {
            return (LockState == LockState.OurLock && IsOpened());
        }

        public bool IsOpened()
        {
            return !(LocalState == FileState.None || LocalState == FileState.InDepot);
        }

        public bool IsMarked()
        {
            return (LocalState == FileState.MarkedForAdd || LocalState == FileState.MarkedForAddMove ||
                    LocalState == FileState.MarkedForDelete || LocalState == FileState.MarkedForDeleteMove ||
                    LocalState == FileState.MarkedForEdit);
        }

        public bool IsInitialized()
        {
            return (this.TimeStamp != default(DateTime));
        }

        /// <summary>
        /// Display Status in Editor Window
        /// </summary>
        public void OnGUI()
        {
            GUILayout.BeginVertical("box");
            GUILayout.BeginHorizontal();
            GUILayout.Label("TimeStamp: ", _nameWidth);
            GUILayout.Label(TimeStamp.ToString("u"), _valueWidth);
            GUILayout.EndHorizontal();

            GUILayout.BeginHorizontal();
            GUILayout.Label("UpdateType: ", _nameWidth);
            GUILayout.Label(UpdateType.ToString(), _valueWidth);
            GUILayout.EndHorizontal();

            GUILayout.BeginHorizontal();
            GUILayout.Label("LocalState: ", _nameWidth);
            GUILayout.Label(LocalState.ToString(), _valueWidth);
            GUILayout.EndHorizontal();

            GUILayout.BeginHorizontal();
            GUILayout.Label("OtherState: ", _nameWidth);
            GUILayout.Label(OtherState.ToString(), _valueWidth);
            GUILayout.EndHorizontal();

            GUILayout.BeginHorizontal();
            GUILayout.Label("DepotState: ", _nameWidth);
            GUILayout.Label(DepotState.ToString(), _valueWidth);
            GUILayout.EndHorizontal();

            GUILayout.BeginHorizontal();
            GUILayout.Label("RevisionState: ", _nameWidth);
            GUILayout.Label(RevisionState.ToString(), _valueWidth);
            GUILayout.EndHorizontal();

            GUILayout.BeginHorizontal();
            GUILayout.Label("ResolvedState: ", _nameWidth);
            GUILayout.Label(ResolvedState.ToString(), _valueWidth);
            GUILayout.EndHorizontal();

            GUILayout.BeginHorizontal();
            GUILayout.Label("StorageType: ", _nameWidth);
            GUILayout.Label(StorageType.ToString(), _valueWidth);
            GUILayout.EndHorizontal();

            GUILayout.BeginHorizontal();
            GUILayout.Label("LockState: ", _nameWidth);
            GUILayout.Label(LockState.ToString(), _valueWidth);
            GUILayout.EndHorizontal();

            GUILayout.EndVertical();
        }
    }
    /// <summary>
    /// Stores and periodically updates the Perforce status of all the assets
    /// </summary>
    /// 

    /// <summary>
    /// This class is used to store the cached results for each "node" we keep track of in this project
    /// </summary>
    public class AssetEntry
    {
        public AssetStatus Status;
        public FileMetaData Meta;
        public DateTime Update;
        public ReconcileEntry Reconcile;
        public List<File> OpenedList;

        public AssetEntry()
        {
            Status = new AssetStatus();
            Meta = new FileMetaData();
            Status.TimeStamp = Update = default(DateTime);
            OpenedList = new List<File>();
        }

        public bool Dirty
        {
            get { return (Update == default(DateTime)); }
            set
            {
                if (value == true)
                {
                    Status.TimeStamp = Update = default(DateTime);
                }
            }
        }

        public void AddOpenedFile(File entry)
        {
            OpenedList.Add(entry);
        }
    }

    public class AssetStatusCache
    {
        private static readonly ILog log = LogManager.GetLogger(typeof(AssetStatusCache));

        private static object _lockUpdated = new object();    // lock object for thread response.
        private static bool _queryDone = false;
        private static string[] _queryContent;

        private static float _pollRate = 10;    // every 10 seconds
        private static DateTime _lastRefresh;

        /// <summary>
        /// This delegate is triggered when the status of an asset changes
        /// </summary>
        public delegate void OnAssetStatusChangedDelegate(PerforceConnection aConnection);

        public static event OnAssetStatusChangedDelegate OnAssetStatusChanged
        {
            add
            {
                if (_OnAssetStatusChanged == null)
                {
                    // We had no reason to get updated before, so do it now
                    Engine.OnOperationPerformed += OnEngineOperationPerformed;
                }
                _OnAssetStatusChanged += value;
            }
            remove
            {
                _OnAssetStatusChanged -= value;
                if (_OnAssetStatusChanged == null)
                {
                    // We no longer have any reason to be updated
                    Engine.OnOperationPerformed -= OnEngineOperationPerformed;
                }
            }
        }

        // The internal event that is actually registered with
        static event OnAssetStatusChangedDelegate _OnAssetStatusChanged;

        // The caches
        static Dictionary<string, AssetEntry> _Entries;

        // The background fstat thread
        private static MetaDataQueue _dataQueue;

        public static void Initialize()
        {
            _Entries = new Dictionary<string, AssetEntry>();
            PendingDirty = true;

            _dataQueue = new MetaDataQueue();

            _queryDone = false;
            _lastRefresh = DateTime.Now;
            EditorApplication.update += OnUpdate;
        }

        /// <summary>
        /// Run periodically to see if Icons need to be updated in the project windows.
        /// CheckForUpdate() gets set to true when the BG thread is done with some fstat fetches.
        /// </summary>
        static void OnUpdate()
        {
            if (Config.ValidConfiguration && Config.DisplayStatusIcons && Config.IsEditing())
			{
                if (CheckForUpdate())
                {
                    //log.Debug("AssetStatusCache OnUpdate");

                    // Update ChangeManager with new fstats
                    ChangeManager.OnUpdatedFiles(LastUpdateStrings());  

                    // Refresh the Project Window
                    Icons.UpdateDisplay();
                    ClearUpdate();
                }
            }
        }

        /// <summary>
        /// Used by the Background Thread to signal completion of a file status retrieval
        /// </summary>
        public static void SignalUpdate(string[] files)
        {
            lock (_lockUpdated)
            {
                _queryDone = true;
                _queryContent = files;
            }
        }

        /// <summary>
        /// Returns true if a file status update is pending
        /// Also resets the query state at the same time.
        /// </summary>
        /// <returns>true</returns>
        public static bool CheckForUpdate()
        {
            bool rv = false;
            lock (_lockUpdated)
            {
                rv = _queryDone;
                //if (rv) log.Debug("Signal!");
            }
            return rv;
        }

        public static string[] LastUpdateStrings()
        {
            return _queryContent;
        }

        public static void ClearUpdate()
        {
            lock (_lockUpdated)
            {
                _queryDone = false;
            }
        }

        /// <summary>
        /// Generic method that fetches the cached AssetEntry which includes 
        /// AssetStatus (checked out, out of date, etc...)
        /// FileMetaData (server "fstat" result)
        /// </summary>
        public static AssetEntry GetAssetEntry(string aAssetPath)
        {
            AssetEntry entry;
            string path = Utils.GetEffectivePath(aAssetPath);
            if (!_Entries.TryGetValue(path, out entry))
            {
                //log.Debug("Creating DEFAULT: " + path);
                entry = new AssetEntry();
                _Entries[path] = entry;
            }

            return entry;
        }

        /// <summary>
        /// Get a cached asset status, don't go to the server for it.
        /// </summary>
        /// <param name="aAssetPath">Asset Path</param>
        /// <returns>AssetStatus</returns>
        public static AssetStatus GetCachedAssetStatus(string aAssetPath)
        {
            AssetEntry entry = GetAssetEntry(aAssetPath);
            return entry.Status;
        }

        /// <summary>
        /// Get a cached asset metadata, don't go to the server for it.
        /// </summary>
        /// <param name="aAssetPath">Asset Path</param>
        /// <returns>FileMetaData</returns>
        public static FileMetaData GetCachedMetaData(string aAssetPath)
        {
            AssetEntry entry = GetAssetEntry(aAssetPath);
            return entry.Meta;
        }

        /// <summary>
        /// Get a cached asset metadata, don't go to the server for it.
        /// </summary>
        /// <param name="spec">FileSpec</param>
        /// <returns>FileMetaData</returns>
        public static FileMetaData GetCachedMetaData(FileSpec spec)
        {
            string path = Utils.LocalPathToAssetPath(spec.LocalPath.Path);
            AssetEntry entry = GetAssetEntry(path);
            return entry.Meta;
        }

        public static DateTime GetCacheUpdated(string aAssetPath)
        {
            AssetEntry entry = GetAssetEntry(aAssetPath);
            return entry.Update;
        }

        /// <summary>
        /// Return cached asset status.
        /// If it has never come from the server (been initialized) put in a background
        /// request to update it.
        /// </summary>
        /// <param name="aAssetPath">Asset path</param>
        /// <returns>AssetStatus</returns>
        public static AssetStatus GetCachedAssetStatusAndUpdateDefaults(string aAssetPath)
        {
            AssetEntry entry = GetAssetEntry(aAssetPath);

            if (!entry.Status.IsInitialized())
            {
                string[] paths = {aAssetPath};
                GetFstatsFromServer(paths);
            }
            return entry.Status;
        }

        /// <summary>
        /// Return cached asset MetaData.
        /// If it has never come from the server (been initialized) put in a background
        /// request to update it.
        /// </summary>
        /// <param name="aAssetPath">Asset path</param>
        /// <returns>FileMetaData</returns>
        public static FileMetaData GetCachedMetaDataAndUpdateDefaults(string aAssetPath)
        {
            AssetEntry entry = GetAssetEntry(aAssetPath);
            if (!entry.Status.IsInitialized())
            {
                string[] paths = { aAssetPath };
                GetFstatsFromServer(paths);
            }
            return entry.Meta;
        }

        // A flag for pending changes to check if something has changedIgnore file name
        public static bool PendingDirty { get; set; }

        /// <summary>
        /// Given the meta data, update AssetStatus which drives the P4Connect icon presentation
        /// </summary>
        public static void AssetStatusFromMetaData(AssetStatus status, FileMetaData aMeta)
        {
            // Debug.Log("StoreAssetStatus: " + Logger.FileMetaDataToString(aMeta));

            if (aMeta == null)
                return;

            // Fill out the struct
            switch (aMeta.Type.BaseType)
            {
                case BaseFileType.Text:
                    status.StorageType = StorageType.Text;
                    break;
                case BaseFileType.Binary:
                    status.StorageType = StorageType.Binary;
                    break;
                default:
                    status.StorageType = StorageType.Other;
                    break;
            }


            status.LocalState = Engine.ParseFileAction(aMeta.Action);
            if (status.LocalState == FileState.None)
            {
                // Check to see if Perforce knows this file so we can override the localState to InDepot.
                if (aMeta.IsMapped || aMeta.HeadAction != FileAction.None)
                    status.LocalState = FileState.InDepot;
            }

            if (aMeta.OtherActions != null)
            {
                status.OtherState = Engine.ParseFileAction(aMeta.OtherActions[0]);
            }

            if (aMeta.HaveRev >= aMeta.HeadRev)
                status.RevisionState = RevisionState.HasLatest;
            else
                status.RevisionState = RevisionState.OutOfDate;

            if (aMeta.Unresolved)
                status.ResolvedState = ResolvedState.NeedsResolve;
            else
                status.ResolvedState = ResolvedState.None;

            if (aMeta.HeadAction == FileAction.MoveDelete || aMeta.HeadAction == FileAction.Delete)
                status.DepotState = DepotState.Deleted;
            else
                status.DepotState = DepotState.None;

            status.TimeStamp = DateTime.Now;

            status.LockState = Engine.GetLockState(aMeta);
            status.UpdateType = AssetStatus.LastUpdateType.OnServer;

            //  Debug.Log("AssetStatus: " + status.ToString());
        }

        /// <summary>
        /// Given a Reconcile entry, update AssetStatus which drives the P4Connect icon presentation
        /// </summary>
        public static void AssetStatusFromReconcileEntry(AssetStatus status, ReconcileEntry entry)
        {
           // Debug.Log("AssetStatusFromReconcileEntry: " + Logger.ReconcileEntryToString(entry));

            if (entry == null)
                return;

            // Fill out the struct
            switch (entry.Type.BaseType)
            {
                case BaseFileType.Text:
                    status.StorageType = StorageType.Text;
                    break;
                case BaseFileType.Binary:
                    status.StorageType = StorageType.Binary;
                    break;
                default:
                    status.StorageType = StorageType.Other;
                    break;
            }

            status.LocalState = Engine.ParseFileAction(entry.Action);

            // Otherstate is unknown when generated by ReconcileEntry
            //status.OtherState = FileState.None;

            if (entry.WorkRev.Equals(entry.Version))
            {
                status.RevisionState = RevisionState.HasLatest;
            }
            else
            {
                status.RevisionState = (entry.WorkRev.Rev == 0) ? RevisionState.None : RevisionState.OutOfDate;
            }

            if (entry.Action == FileAction.Unresolved)
                status.ResolvedState = ResolvedState.NeedsResolve;
            else
                status.ResolvedState = ResolvedState.None;

            if (entry.Action == FileAction.MoveDelete || entry.Action == FileAction.Delete)
                status.DepotState = DepotState.Deleted;
            else
                status.DepotState = DepotState.None;

            status.TimeStamp = DateTime.Now;
            status.UpdateType = AssetStatus.LastUpdateType.OnServer;

            // LockState is unknown when generated by ReconcileEntry
            //status.LockState = Engine.GetLockState(aMeta);

            //Debug.Log("AssetStatus: " + status.ToString());
        }

        /// <summary>
        /// Update an asset status from a File entry (result of p4 opened)
        /// </summary>
        /// <param name="status"></param>
        /// <param name="entry"></param>
        /// <returns></returns>
        public static void UpdateAssetStatusFromFile(AssetStatus status, File entry)
        {
            //Debug.Log("UpdateAssetStatusFromFile: " + entry.ToStringNullSafe());

            if (entry == null)
                return;

            // Fill out the struct
            switch (entry.Type.BaseType)
            {
                case BaseFileType.Text:
                    status.StorageType = StorageType.Text;
                    break;
                case BaseFileType.Binary:
                    status.StorageType = StorageType.Binary;
                    break;
                default:
                    status.StorageType = StorageType.Other;
                    break;
            }

            // see if this entry is from our local workspace
            if (entry.User == Config.Username && entry.Client == Config.Workspace)
            {
                status.LocalState = Engine.ParseFileAction(entry.Action);

                if (entry.HaveRev.Equals(entry.Version))
                {
                    status.RevisionState = RevisionState.HasLatest;
                }
                else
                {
                    status.RevisionState = (entry.HaveRev.Rev == 0) ? RevisionState.None : RevisionState.OutOfDate;
                }

                status.ResolvedState = (entry.Action == FileAction.Unresolved) ? ResolvedState.NeedsResolve : ResolvedState.None;

                if (entry.Action == FileAction.MoveDelete || entry.Action == FileAction.Delete)
                    status.DepotState = DepotState.Deleted;
                else
                    status.DepotState = DepotState.None;

                status.LockState = entry.Locked  ? LockState.OurLock : LockState.None;
            }
            else  // Must be someone using my files in a remote location
            {
                status.OtherState = Engine.ParseFileAction(entry.Action);

                if (status.LockState == LockState.None && entry.Locked)
                    status.LockState = LockState.TheirLock;
            }
            status.TimeStamp = DateTime.Now;
            status.UpdateType = AssetStatus.LastUpdateType.OnServer;

            if (entry.Locked)
                status.LockState = LockState.OurLock;

            //Debug.Log("AssetStatus: " + status.ToString());
            return;
        }


        /// <summary>
        /// We have new Metadata so Update the cache
        /// </summary>
        /// <param name="fmdlist">IEnumerable MetaDataList</param>
        public static void UpdateCacheWithMetadata(IEnumerable<FileMetaData> fmdlist)
        {
            foreach (var fmd in fmdlist)
            {
                var entry = GetAssetEntry(fmd.ToAssetPath());
                if (entry != null)
                {
                    entry.Meta = fmd;

                    // Since the Metadata changed, re-create the Asset Status Also
                    AssetStatusFromMetaData(entry.Status, fmd);
                }
            }
        }

        /// <summary>
        /// This functions gets called when P4Connect does *something* to files
        /// In this case we update the files status
        /// </summary>
        static void OnEngineOperationPerformed(PerforceConnection aConnection, IEnumerable <string> aFiles, AssetOperation op)
        {
            // ToDo:  Look at filtering by operation.  Some of these Fstats may have already been updated
            GetFstatsFromServer(aFiles);  // retrieve new fstats in the background
        }

        /// <summary>
        /// Given a collection of folders and Asset paths, update file Metadata information from the server
        /// Queues an ASYNCHRONOUS request for the asset paths to a background thread
        /// </summary>
        /// <param name="paths">collection of Asset paths, and folders</param>
        public static void GetFstatsFromServer(IEnumerable<string> paths)
        {
            if (paths.Any())
            {
                string[] paths1 = paths.AddDirectoryWildcards().ToArray();

                //log.Debug("GetFstatsFromServer: " + Logger.StringArrayToString(paths1));

                _dataQueue.QueueQuery(paths1);
            }  
        }

        /// <summary>
        /// Checks current cached asset status, and if not initialized, retrieves it from the server
        /// Updates run ASYNCRONOUSLY
        /// </summary>
        /// <param name="paths">assetpaths to retrieve from server if still dummies</param>
        public static void UpdateDefaultsFromServer(IEnumerable<string> paths)
        {
            var updatePaths = new HashSet<string>();
            foreach (string t in paths)
            {
                if (! Utils.IsDirectory(t))   // Skip subdirectories
                {
                    var status = GetCachedAssetStatus(t);
                    if (!status.IsInitialized())
                    {
                        updatePaths.Add(t);
                    }
                }
            }
            if (updatePaths.Count > 0)
            {
                GetFstatsFromServer(updatePaths);
            }
        }

        /// <summary>
        /// Given a folder, invalidate all cache data for members
        /// </summary>
        /// <param name="path">Path to dirty folder</param>
        public static void MarkFolderAsDirty(string path)
        {
            path = Utils.RemoveDirectoryWildcards(path);
            log.Debug("dirtypath: " + path);

            IEnumerable<string> fullKeys = _Entries.Keys.Where(currentKey => currentKey.StartsWith(path));

            foreach (string key in fullKeys)
            {
                _Entries[key].Dirty = true;
                log.Debug("dirt: " + key);
            }
        }

        /// <summary>
        /// Given an asset path, mark this asset as Dirty
        /// So it will be re-fstated later.
        /// </summary>
        /// <param name="assetPath"></param>
        public static void MarkAsDirty(string assetPath)
        {
            //log.Debug("DIRTY: " + assetPath);
            var entry = GetAssetEntry(assetPath);
            entry.Update = default(DateTime);
            entry.Status.TimeStamp = entry.Update;
        }

        /// <summary>
        /// Mark the contents of a List of FileAndMetas as dirty
        /// </summary>
        /// <param name="fam">FileAndMetas Collection</param>
        static public void MarkAsDirty(IEnumerable<FileAndMeta> fam)
        {
            if (fam == null)
                return;

            foreach (var f in fam)
            {
                if (f.File != null)
                {
                    MarkAsDirty(f.File.ToAssetPath());
                }
                if (f.Meta != null)
                {
                    MarkAsDirty(f.Meta.ToAssetPath());
                }
            }
        }

        /// <summary>
        /// Using the Perforce connection, get a matching AssetStatus for each Assetpath
        /// </summary>
        /// <param name="aConnection">Perforce Connection</param>
        /// <param name="aFiles">A List of asset paths to retrieve</param>
        /// <param name="aOutStatuses">A list of statuses, one per aFile</param>
        //public static void GetAssetStatusesFromPaths(PerforceConnection aConnection, List<string> aFiles,
        //    List<AssetStatus> aOutStatuses)
        //{
        //    GetAssetStatuses(aConnection, GetEffectiveFileSpecs(aFiles).ToList(), aOutStatuses);
        //}

        /// <summary>
        /// Using Perforce connection, get a matching AssetStatus for each Assetpath
        /// </summary>
        /// <param name="aConnection">Perforce Connection</param>
        /// <param name="aFiles">A List of asset paths to retrieve</param>
        /// <returns>A List of AssetStatus, one for each <paramref name="aFiles"/> entry</returns>
        //static public List<AssetStatus> GetAssetStatusesFromPaths(PerforceConnection aConnection,
        //    List<string> aFiles)
        //{
        //    List<AssetStatus> aOutStatuses = new List<AssetStatus>();
        //    GetAssetStatusesFromPaths(aConnection, aFiles, aOutStatuses);
        //    return aOutStatuses;
        //}

        /// <summary>
        /// Using the Perforce connection, get a matching AssetStatus for each FileSpec
        /// If the metadata for a file is not in Perforce, we provide a "local" AssetStatus instead.
        /// </summary>
        /// <param name="aConnection">a valid Perforce Connection</param>
        /// <param name="aFiles"> A list of FileSpecs to be looked up </param>
        /// <param name="aOutStatuses">an AssetStatus is added to this list for each <paramref name="aFiles"/> entry</param>
        //static void GetAssetStatuses(PerforceConnection aConnection, List<FileSpec> aFiles,
        //    List<AssetStatus> aOutStatuses)
        //{
        //    IEnumerable<string> assetNames = GetAssetPathsFromFileSpecs(aFiles);
        //    string[] files = assetNames.ToArray();

        //   Debug.Log("retrieving: " + Logger.StringArrayToString(files));

        //    List<string> notInitialized = new List<string>();

        //    // Collect results here for return later
        //    AssetStatus[] stats = new AssetStatus[files.Count()];

        //    // Get The Asset Status for each file,  if not initialized add to "not_initialized" list
        //    for (int i = 0; i < files.Count(); i++)
        //    {
        //        stats[i] = GetCachedAssetStatus(files[i]);
        //        if (!stats[i].IsInitialized())
        //        {
        //            notInitialized.Add(files[i]);
        //        }
        //    }

        //    // Now Ask for any uninitialized AssetStatus's from the server      
        //    if (notInitialized.Count > 0)
        //    {
        //        log.Debug("Going to server for: " + Logger.StringArrayToString(notInitialized.ToArray()));
        //        GetFstatsFromServer(notInitialized);
        //    }

        //    // Finally update the "holes" in the statuses originally returned
        //    for (int i = 0; i < files.Count(); i++)
        //    {
        //        if (!stats[i].IsInitialized())
        //        {
        //            stats[i] = GetCachedAssetStatus(files[i]);
        //        }
        //    }

        //    aOutStatuses.AddRange(stats);

        //    log.Debug("assetstatuses: " + Logger.AssetStatusListToString(aOutStatuses));
        //}

        /// <summary>
        /// Goes to the server, updates cache with latest about the files specified
        /// Frequently runs in a background thread.
        /// </summary>
        /// <param name="aConnection">A valid Perforce connection</param>
        /// <param name="aFiles">AssetPath list to retrieve info about</param>
        /// <returns>enumeration of asset paths which were updated</returns>
        public static IEnumerable<string> GetAssetMetaData(PerforceConnection aConnection, IEnumerable<string> aFiles)
        {
            //log.Debug("GetAssetMetaData: " + Logger.StringArrayToString(aFiles.ToArray()));
            var returnList = new HashSet<string>();

            if (aFiles.Any())
            {
                HashSet<string> original = new HashSet<string>(aFiles);
                HashSet<string> checkedList = null;

                DateTime startTimestamp = DateTime.Now;

                Options fsopts = new Options();
                fsopts["-Op"] = null; // Return "real" clientpaths

                var mdlist = Engine.GetFileMetaData(aConnection, original.ToDepotSpecs().ToList(), fsopts);

                if (mdlist != null)
                {
                    // with a good response, we store the retrieved meta data in the AssetCache
                    //StorePerforceMetaData(mdlist);    // This is done in Engine.GetFileMetaData() instead

                    checkedList = new HashSet<string>(mdlist.ToAssetPaths().EffectivePaths());
                }

                // Remove wildcard entries from original list.
                // Create Local MetaData entries for files unknown by Perforce
                IEnumerable<string> leftOvers = (checkedList != null) ? original.RemoveWildCards().Except(checkedList) : original;
                if (leftOvers.Any())
                    StoreLocalMetaData(leftOvers);
               

                if (Config.DisplayP4Timings)
                {
                    double deltaInnerTime = (DateTime.Now - startTimestamp).TotalMilliseconds;
                    aConnection.AppendTimingInfo("GetAssetMetaData " + deltaInnerTime + " ms");
                }

                if (checkedList != null)
                {
                    returnList.UnionWith(checkedList); 
                }
                returnList.UnionWith(leftOvers);
            }
            return returnList;
        }

        /// <summary>
        /// We have fresh metadata from the server
        /// Lets store it in the Asset Cache
        /// </summary>
        /// <param name="mdlist">List of Metadata to store</param>
        public static void StorePerforceMetaData(IList<FileMetaData> mdlist)
        {
            if (mdlist == null)
                return;

            foreach (var md in mdlist)
            {
                if (md == null || md.LocalPath == null || md.LocalPath.Path == null || md.LocalPath.Path.Length == 0)
                {
                    log.Debug("Missing LocalPath - MetaData: " + Logger.FileMetaDataToString(md));
                    continue;
                }

                // Create the AssetStatus and FileMetaData entries for each file known by the server
                string fname = Utils.GetEffectivePath(Utils.LocalPathToAssetPath(md.LocalPath.Path));
                AssetEntry entry = new AssetEntry
                {
                    Meta = md,
                    Update = DateTime.Now
                };
                AssetStatusFromMetaData(entry.Status, md);
                _Entries[fname] = entry;

                //log.Debug("AssetEntry: " + fname + " CREATED " + entry.Status.ToStringNullSafe());
            }
        }

        /// <summary>
        /// The metadata from the server came back, and did not include these files
        /// So we need to make valid Cache entries as if they are Local files only
        /// </summary>
        /// <param name="files">Asset Paths of files to cache</param>
        public static void StoreLocalMetaData(IEnumerable<string> files)
        {
            if (files == null)
                return;

            // For "leftover" files not known by the server, we provide a default 
            // AssetEntry with the update field set.
            foreach (string f in files)
            {
                AssetEntry entry = new AssetEntry();
                entry.Meta = new FileMetaData();
                entry.Status = new AssetStatus();

                entry.Status.TimeStamp = entry.Update = DateTime.Now;
                entry.Status.UpdateType = AssetStatus.LastUpdateType.OffServer;  // We verified that the server doesn't have a record of this.
                _Entries[f] = entry;
                //log.Debug("AssetEntry: " + f + " LOCAL " + entry.Status.ToStringNullSafe());
            }
        }

        /// <summary>
        /// Returns a proper list of file spec given a list of paths, skipping folders, generating folder meta files instead
        /// </summary>
        /// <param name="aAssetPaths">Asset Path strings</param>
        /// <returns>FileSpecs</returns>
        static IEnumerable<FileSpec> GetEffectiveFileSpecs(IEnumerable<string> aAssetPaths)
        {
            foreach (var path in aAssetPaths)
            {
                yield return FileSpec.LocalSpec(Utils.AssetPathToLocalPath(Utils.GetEffectivePath(path)));
            }
            yield break;
        }

        /// <summary>
        /// Translates a collection of asset paths (including folders) into a collection of LocalSpec FileSpecs
        /// </summary>
        /// <param name="aAssetPaths">Asset paths to become FileSpec </param>
        /// <returns>FileSpecs</returns>
        public static IEnumerable<FileSpec> GetFileSpecs(IEnumerable<string> aAssetPaths)
        {
            foreach (var path in aAssetPaths)
            {
                yield return FileSpec.LocalSpec(Utils.AssetPathToLocalPath(path));
            }
            yield break;
        }

        /// <summary>
        /// Return a collection of Asset paths given a list of FileSpecs 
        /// (using the LocalPath of the FileSpec)
        /// </summary>
        /// <param name="fs">FileSpecs</param>
        /// <returns>strings</returns>
        public static IEnumerable<string> GetAssetPathsFromFileSpecs(IEnumerable<FileSpec> fs)
        {
            foreach (var f in fs)
            {
                yield return Utils.LocalPathToAssetPath(f.LocalPath.Path);
            }
            yield break;
        }

        /// <summary>
        /// Return a collection of Asset paths given a list of FileMetaData
        /// </summary>
        /// <param name="fmd_list">FileMetaData collection</param>
        /// <returns>string collection </returns>
        public static IEnumerable<string> GetAssetPathsFromFileMetaData(IEnumerable<FileMetaData> fmd_list)
        {
            foreach (var fm in fmd_list)
            {
                yield return Utils.LocalPathToAssetPath(fm.LocalPath.Path);
            }
            yield break;
        }

    
        #region InspectorGUI

        [CustomEditor(typeof(UnityEditor.DefaultAsset), true)]
        public class PerforceAssetPropertiesEditor : Editor
        {
            private AssetEntry _entry;
            private string _assetPath;

            public override void OnInspectorGUI()
            {
                //GUI.enabled = false;
                DrawDefaultInspector();
                //GUI.enabled = true;

                //EditorGUILayout.BeginHorizontal();
                EditorGUILayout.LabelField("Perforce Properties", EditorStyles.boldLabel);
                EditorGUILayout.BeginVertical("box");

                _assetPath = AssetDatabase.GetAssetPath(target.GetInstanceID());
                EditorGUILayout.LabelField("Path: " + _assetPath);

                _entry = GetAssetEntry(_assetPath);
                if (_entry == null)
                {
                    EditorGUILayout.LabelField("No Asset Entry Found");
                }
                else
                {
                    _entry.Status.OnGUI();
                }

                var guid = AssetDatabase.AssetPathToGUID(_assetPath);
                EditorGUILayout.LabelField("GUID: " + guid);
                string[] dependents = AssetDatabase.GetDependencies(_assetPath, false);
                foreach (var dep in dependents)
                {
                    EditorGUILayout.LabelField("-- " + dep);
                }

                EditorGUILayout.EndVertical();
            }
        }
        #endregion

        #region MetaDataQueue

        /// <summary>
        /// Encapsulates a thread with an input queue of string arrays.  
        /// Issues "p4 fstat" command for each entry
        /// </summary>
        class MetaDataQueue
        {
            private Thread _worker;
            readonly Queue<string[]> _queue = new Queue<string[]>();
            readonly object _locker = new object();
            readonly object _lockUpdated = new object(); 
            private readonly EventWaitHandle _wh = new AutoResetEvent(false);

           // private bool queryDone = false;

            public MetaDataQueue()
            {
                _worker = new Thread(Work);
                _worker.Start();
            }

            ~MetaDataQueue()
            {
                QueueQuery(null);
                _worker.Join();
                _wh.Close();
            }

            public void QueueQuery(string[] paths)
            {
                lock (_locker) _queue.Enqueue(paths);
                _wh.Set();
            }

            /// <summary>
            /// Work - This is run by the background thread.
            /// It issues a command on the queue
            /// Then waits for an Event to proceed.
            /// </summary>
            private void Work()
            {
                while (true)
                {
                    var argument = new HashSet<string>();
                    lock (_locker)
                    {
                        while (_queue.Count > 0)
                        {
                            argument.UnionWith(_queue.Dequeue()); // Collect all pending requests into one list.
                        }
                    }

                    if (argument.Count > 0)
                    {
                        string[] changedFiles = new string[0];
                        Engine.PerformConnectionOperation(con =>
                        {
                           changedFiles = AssetStatusCache.GetAssetMetaData(con, argument).ToArray();
                        }, true);

                        if (changedFiles.Length > 0)
                            SignalUpdate(changedFiles);
                    }
                    else
                    {
                        _wh.WaitOne();
                    }
                }

            }
        }

        #endregion
    }
}