#region
/* -----------------------------------------------------------------------
 * <copyright file="FileState.cs" company="GRNet">
 * 
 * Copyright 2011-2012 GRNET S.A. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or
 * without modification, are permitted provided that the following
 * conditions are met:
 *
 *   1. Redistributions of source code must retain the above
 *      copyright notice, this list of conditions and the following
 *      disclaimer.
 *
 *   2. 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.
 *
 *
 * THIS SOFTWARE IS PROVIDED BY GRNET S.A. ``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 GRNET S.A OR
 * 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.
 *
 * The views and conclusions contained in the software and
 * documentation are those of the authors and should not be
 * interpreted as representing official policies, either expressed
 * or implied, of GRNET S.A.
 * </copyright>
 * -----------------------------------------------------------------------
 */
#endregion
using System.Diagnostics.Contracts;
using System.IO;
using System.Reflection;
using NHibernate;
using NHibernate.Criterion;
using Pithos.Interfaces;
using Pithos.Network;
using log4net;

namespace Pithos.Core
{
    using System;
    using System.Collections.Generic;    

    /// <summary>
    /// TODO: Update summary.
    /// </summary>
    /*[ActiveRecord]*/
    public class FileState /*: ActiveRecordLinqBase<FileState>*/
    {
        private static readonly ILog Log = LogManager.GetLogger(MethodBase.GetCurrentMethod().DeclaringType);


        private IList<FileTag> _tags = new List<FileTag>();
        private DateTime? _modified;

        /*[PrimaryKey(PrimaryKeyType.Guid)]*/
        public virtual Guid Id { get; set; }

        
        ////[Property(Unique = true, UniqueKey = "IX_FileState_ObjectID")]
        /*////[Property]*/
        public virtual string ObjectID { get; set; }

        public virtual long FileId { get; set; }

 /*       //[Property(Unique = true, UniqueKey = "IX_FileState_FilePath")]*/
        public virtual string FilePath { get; set; }

        /*////[Property]*/
        public virtual FileOverlayStatus? OverlayStatus { get; set; }

        /*////[Property]*/
        public virtual FileStatus? FileStatus { get; set; }

        /*////[Property]*/
        public virtual string ConflictReason { get; set; }

        /// <summary>
        /// The tophash value of the file, calculated by using a Merkle hash with the SHA256 algorithm
        /// </summary>
        /// <remarks>
        /// The SHA256 algorithm is substantially more expenive than other algorithms.
        /// Recalculating the Checksum should be avoided whenever possible.
        /// </remarks>
        ////[Property]
        public virtual string Checksum { get; set; }

        /// <summary>
        /// An easy to calcualte hash over the entire file, used to detect file changes
        /// </summary>
        /// <remarks>The algorithm used to calculate this hash should be cheap</remarks>
        //[Property(NotNull = true, Default = "")]
        public virtual string ETag { get; set; }

        ////[Property(NotNull = true, Default = "")]
        //public string LastMD5 { get; set; }

        ////[Property]
        public virtual string Hashes { get; set; }

        ////[Property]
        public virtual DateTime? LastWriteDate { get; set; }

        ////[Property]
        public virtual long? LastLength { get; set; }
        
        ////[Property]
        public virtual long? Version { get; set; }

        ////[Property]
        public virtual DateTime? VersionTimeStamp { get; set; }


        ////[Property]
        public virtual bool IsShared { get; set; }

        ////[Property]
        public virtual string SharedBy { get; set; }

        ////[Property]
        public virtual bool ShareWrite { get; set; }

        ////[Property]
        public virtual bool IsFolder { get; set; }

        //[HasMany(Cascade = ManyRelationCascadeEnum.AllDeleteOrphan, Lazy = true, Inverse = true)]
        public virtual IList<FileTag> Tags
        {
            get { return _tags; }
            set { _tags = value; }
        }

        ////[Property]
        public virtual DateTime? Modified
        {
            //Modified is only used for information/debugging puproses in the database. It's value is set to the current date if it's not modified by some other function
            get { return _modified??DateTime.Now; }
            set { _modified = value; }
        }


        public virtual FileSystemInfo GetFileSystemInfo()
        {
            if (String.IsNullOrWhiteSpace(FilePath))
                throw new InvalidOperationException();
            Contract.EndContractBlock();

            return Directory.Exists(FilePath) ?
                (FileSystemInfo)new DirectoryInfo(FilePath)
                : new FileInfo(FilePath);
        }

        public virtual Uri GetRelativeUrl(AccountInfo accountInfo)
        {
            if (accountInfo==null)
                throw new ArgumentNullException("accountInfo");
            Contract.EndContractBlock();

            var fsi=GetFileSystemInfo();
            return fsi.AsRelativeUrlTo(accountInfo.AccountPath);
        }
     


        public static FileState CreateFor(FileSystemInfo info,IStatusNotification notification)
        {
            if(info==null)
                throw new ArgumentNullException("info");
            Contract.EndContractBlock();
            
            //The file may not exist, if the call is made for a new server object

            //var md5 = (info is DirectoryInfo || !info.Exists)
            //    ?Signature.MD5_EMPTY
            //    :((FileInfo)info).ComputeShortHash(notification);

            var length = (info is DirectoryInfo || !info.Exists)
                             ? 0
                             : ((FileInfo) info).Length;

            var lastWriteTime = (info.Exists)
                                ?(DateTime?)info.LastWriteTime
                                :null;
            var fileState = new FileState
                                {
                                    FilePath = info.FullName,
                                    OverlayStatus = FileOverlayStatus.Unversioned,
                                    FileStatus = Pithos.Core.FileStatus.Created,               
                                    ETag=String.Empty,
                                    //LastMD5=md5,
                                    LastWriteDate=lastWriteTime,
                                    LastLength=length,
                                    IsFolder=(info is DirectoryInfo),
                                    Modified=DateTime.Now
                                };
            return fileState;
        }





        public virtual string ToDebugString()
        {
            return String.Format("[STATE] FilePath:[{0}] ObjectID:[{1}], ETAG: [{2}], Checksum: [{3}]", FilePath, ObjectID,
                                 ETag, Checksum);
            //return String.Format("[STATE] FilePath:[{0}] ObjectID:[{1}], ETAG: [{2}], Checksum: [{3}] LastMD5:[{4}]", FilePath, ObjectID,
            //                     ETag, Checksum, LastMD5);
        }
    }

    //[ActiveRecord("Tags")]
    public class FileTag //: ActiveRecordLinqBase<FileTag>
    {
        //[PrimaryKey]
        public int Id { get; set; }

        ////[Property]
        public string Name { get; set; }

        ////[Property]
        public string Value { get; set; }

        //[BelongsTo("FileStateId")]
        public FileState FileState { get; set; }

    }

    public class PithosVersion
    {
        public virtual int Id { get; set; }
        public virtual string Version { get; set; }
    }
   
}