using System;
using System.Collections.Generic;
using System.Diagnostics.Contracts;
using System.Dynamic;
using System.Globalization;
using System.IO;
using System.Linq;
using System.Text;
using System.Text.RegularExpressions;
using Newtonsoft.Json;

namespace Pithos.Interfaces
{
    public class ObjectInfo:DynamicObject 
    {
        private readonly List<string> _knownContainers= new List<string>{"trash"};
        public string Name { get; set; }
        public string Hash { get; set; }
        public long Bytes { get; set; }
        public string Content_Type { get; set; }
        public DateTime Last_Modified { get; set; }

        private Dictionary<string, string> _tags=new Dictionary<string, string>();
        public Dictionary<string, string> Tags
        {
            get { return _tags; }
            set { _tags = value; }
        }

        private Dictionary<string, string> _extensions=new Dictionary<string, string>();
        public Dictionary<string, string> Extensions
        {
            get { return _extensions; }
            set
            {
                _extensions = value;
                ExtractKnownExtensions();
            }
        }
        
        
        private Dictionary<string, string> _permissions=new Dictionary<string, string>();
        [JsonProperty("x_object_sharing")]
        [JsonConverter(typeof(PermissionConverter))]
        public Dictionary<string, string> Permissions
        {
            get { return _permissions; }
            set
            {
                _permissions = value;                
            }
        }

        /// <summary>
        /// Version number
        /// </summary>
        [JsonProperty("x_object_version")]
        public long? Version { get; set; }


        /// <summary>
        /// Shared object permissions can be Read or Write
        /// </summary>
        [JsonProperty("x_object_allowed_to")]
        public string AllowedTo { get; set; }


        /// <summary>
        /// Version timestamp
        /// </summary>
        [JsonProperty("X_Object_Version_Timestamp"), JsonConverter(typeof(PithosDateTimeConverter))]
        public DateTime? VersionTimestamp { get; set; }

        [JsonProperty("X_Object_Modified_By")]
        public string ModifiedBy { get; set; }


        public Stream Stream { get; set; }

        public string Account { get; set; }

        public string Container { get; set; }

        public string ContendDisposition { get; set; }

        public string ContentEncoding { get; set; }

        public string Manifest { get; set; }

        private bool _isPublic;
        public bool IsPublic
        {
            get { return !String.IsNullOrWhiteSpace(PublicUrl); }
            set
            {
                if (!value)
                    PublicUrl = "false";
                else if (String.IsNullOrWhiteSpace(PublicUrl))
                    PublicUrl="true";                
            }
        }

        public string PublicUrl { get; set; }

        public ObjectInfo()
        {}

        public ObjectInfo(string accountPath,string accountName,FileInfo fileInfo)
        {
            var relativeUrl = fileInfo.AsRelativeUrlTo(accountPath);
            //The first part of the URL is the container
            var slashIndex = relativeUrl.IndexOf('/');
            var container = relativeUrl.Substring(0, slashIndex);
            //The second is the file's url relative to the container
            var fileUrl = relativeUrl.Substring(slashIndex + 1);

            Account = accountName;
            Container = container;
            Name = fileUrl; 
        }


        private void ExtractKnownExtensions()
        {
            Version=GetLong(KnownExtensions.X_Object_Version);
            VersionTimestamp = GetTimestamp(KnownExtensions.X_Object_Version_Timestamp);
            ModifiedBy = GetString(KnownExtensions.X_Object_Modified_By);
        }

        private string GetString(string name)
        {            
            var value=String.Empty;
            _extensions.TryGetValue(name, out value);
            return value ;                        
        }

        private long? GetLong(string name)
        {
            string version;
            long value;
            return _extensions.TryGetValue(name, out version) && long.TryParse(version, out value)
                       ? (long?) value
                       : null;
        }

        private DateTime? GetTimestamp(string name)
        {
            string version;
            DateTime value;
            if (_extensions.TryGetValue(name, out version) && 
                DateTime.TryParse(version,CultureInfo.InvariantCulture,DateTimeStyles.AdjustToUniversal, out value))
            {
                return value;
            }
            return null;
        }


        public static ObjectInfo Empty = new ObjectInfo
        {
            Name = String.Empty,
            Hash = String.Empty,
            Bytes = 0,
            Content_Type = String.Empty,
            Last_Modified = DateTime.MinValue
        };

        public string RelativeUrlToFilePath(string currentAccount)
        {
            if (Name==null)
                throw new InvalidOperationException("Name can't be null");
            if (String.IsNullOrWhiteSpace(currentAccount))
                throw new ArgumentNullException("currentAccount");
            Contract.EndContractBlock();

            if (this == Empty)
                return String.Empty;

            var unescaped = Uri.UnescapeDataString(Name);
            var path = unescaped.Replace("/", "\\");
            var pathParts=new Stack<string>();
            pathParts.Push(path);
            if (!String.IsNullOrWhiteSpace(Container) && !_knownContainers.Contains(Container))
                pathParts.Push(Container);
            if (!currentAccount.Equals(Account, StringComparison.InvariantCultureIgnoreCase))
            {
                if (Account != null)
                {
                    pathParts.Push(Account);
                    pathParts.Push("others");
                }
            }
            var finalPath=Path.Combine(pathParts.ToArray());
            return finalPath;
        }

        public override bool TrySetMember(SetMemberBinder binder, object value)
        {
            if (binder.Name.StartsWith("x_object_meta"))
            {
                Tags[binder.Name] = value.ToString();
            }
            return false;
        }

        public string GetPermissionString()
        {
            var permissionBuilder = new StringBuilder();
            var groupings = Permissions.GroupBy(pair => pair.Value);
            foreach (var grouping in groupings)
            {
                permissionBuilder.AppendFormat("{0}={1}", grouping.Key, String.Join(",", grouping));
            }
            var permissions = permissionBuilder.ToString();
            return permissions;
        }
    }
}