using System;
using System.Collections.Generic;
using System.Linq;
using System.IO;
using System.Text;
using System.Net;
using System.Net.Sockets;
using System.Threading;
using System.Xml.Linq;
using System.Text.RegularExpressions;

using MudEngine.GameScripts;
using MudEngine.Core.Interfaces;
using MudEngine.Networking;
using MudEngine.Core;
using MudEngine.Game.Environment;

namespace MudEngine.Game.Characters
{
    /// <summary>
    /// Standard Character class used by all character based objects
    /// </summary>
    public class StandardCharacter : BaseScript, INetworked, ISavable, IGameComponent
    {
        #region Properties
        /// <summary>
        /// Gets a reference to the currently active game.
        /// </summary>

        public string Filename
        {
            get
            {
                return this.Game.SavePaths.GetFilePath(DAL.DataTypes.Players, this.Name);
            }
        }

        /// <summary>
        /// Gets what this Characters role on the server is.
        /// </summary>
        public CharacterRoles Role { get; protected set; }

        /// <summary>
        /// Gets what this characters stats are.
        /// </summary>
        public CharacterStats Stats { get; protected set; }

        /// <summary>
        /// User account password
        /// </summary>
        //TODO: Character passwords should be a private set.
        public String Password { get; set; }

        /// <summary>
        /// Flags this object as non-movable in the world.
        /// </summary>
        public Boolean Immovable { get; set; }

        /// <summary>
        /// Gets or Sets if this character is enabled.
        /// When disabled, they can not enter commands.
        /// Characters can have LoggedIn and Connected TRUE with Enabled false resulting in a player connected to
        /// the server but unable to interact.
        /// </summary>
        public Boolean Enabled { get; set; }

        /// <summary>
        /// Gets or Sets if this client is fully logged into the account and located in the World.
        /// </summary>
        public Boolean LoggedIn
        {
            get
            {
                return this._LoggedIn;
            }
            private set
            {
                if (value)
                    this.OnLoginEvent();
                this._LoggedIn = value;
            }
        }

        /// <summary>
        /// Gets if the user is currently connected to a server or not.
        /// </summary>
        public Boolean Connected { get; set; }

        protected CommandSystem Commands { get; private set; }

        public Room CurrentRoom { get; private set; }

        #endregion

        #region Constructors
        public StandardCharacter(StandardGame game, String name, String description)
            : base(game, name, description)
        {
            this.Role = CharacterRoles.Player;

            //Instance this Characters personal Command System with a copy of the command
            //collection already loaded and prepared by the Active Game.
            this.Commands = new CommandSystem(CommandSystem.Commands);

            this.OnConnectEvent += new OnConnectHandler(OnConnect);
            this.OnDisconnectEvent += new OnDisconnectHandler(OnDisconnect);
            this.OnLoginEvent += new OnLoginHandler(OnLogin);
            this.OnWalkEvent += new OnWalkHandler(OnWalk);
            this.OnEnterEvent += new OnEnterHandler(OnEnter);
            this.OnLeaveEvent += new OnLeaveHandler(OnLeave);
        }

        public StandardCharacter(StandardGame game, String name, String description, Socket connection)
            : this(game, name, description)
        {
            this._Connection = connection;

            this._Reader = new StreamReader(new NetworkStream(this._Connection, false));
            this._Writer = new StreamWriter(new NetworkStream(this._Connection, true));

            this._Writer.AutoFlush = true; //Flushes the stream automatically.
        }
        #endregion

        #region Inherited Methods
        public virtual void Initialize()
        {
            //throw new NotImplementedException();
            this.Enabled = true;
        }

        /// <summary>
        /// Destroys any resources used by this character.
        /// Assumes that Save() has already been invoked.
        /// </summary>
        public virtual void Destroy()
        {
            this.Commands = null;
        }

        public override bool Save(String filename)
        {
            return this.Save(filename, true);
        }

        public override bool Save(String filename, Boolean verbose)
        {
            base.Save(filename, true);

            SaveData.AddSaveData("Immovable", Immovable.ToString());
            SaveData.AddSaveData("Password", Password);
            SaveData.AddSaveData("Role", this.Role.ToString());

            if (this.SaveData.Save(filename))
            {
                if (!verbose)
                    this.SendMessage("Save completed.");
            }

            return true;
        }

        public override void Load(string filename)
        {
            base.Load(filename);

            try { this.Immovable = Convert.ToBoolean(this.SaveData.GetData("Immovable")); }
            catch { this.LoadFailedMessage("Immovable"); }

            this.Password = this.SaveData.GetData("Password");

            String role = this.SaveData.GetData("Role");

            this.Role = GetRole(role);
        }
        #endregion

        #region Networking Methods
        /// <summary>
        /// Executes the specified command if it exists in the Command library.
        /// </summary>
        /// <param name="command"></param>
        /// <returns></returns>
        public virtual Boolean ExecuteCommand(string command)
        {
                Boolean result = false;

            if (this.Enabled && this.Connected)
            {
                result = Commands.Execute(command, this);

                if (!result)
                    this.SendMessage("Invalid Command used.");

                SendMessage("");
                SendMessage("Command:", false);

                return result;
            }
            else
            {
                return false;
            }
        }

        /// <summary>
        /// Executes the spcified command if it exists in the Command library.
        /// This method is verbose.  Only messages sent from the Commands will be presented to the player.
        /// The standard new line and "Command: " message is skipped with this method.
        /// </summary>
        /// <param name="command"></param>
        /// <returns></returns>
        public virtual Boolean ExecuteSilentCommand(string command)
        {
            if (this.Enabled)
            {
                Boolean result = Commands.Execute(command, this);

                return result;
            }
            else
                return false;
        }

        public void Connect()
        {
            //this.Initialize();
            this.Connected = true;
            OnConnectEvent();
        }

        public void Disconnect()
        {
            this.Save(this.Filename);

            //Purge all of this characters commands.
            this.Destroy();

            //Close our currently open socket.
            this._Connection.Close();

            this.LoggedIn = false;
            this.Connected = false;

            this.OnDisconnectEvent();
        }

        public virtual void SendMessage(String data)
        {
            this.SendMessage(data, true);
        }

        public virtual void SendMessage(String data, Boolean newLine)
        {
            try
            {
                System.Text.ASCIIEncoding encoding = new System.Text.ASCIIEncoding();
                if (newLine)
                    data += "\n\r";

                this._Connection.Send(encoding.GetBytes(data));
            }
            catch (Exception)
            {
                Disconnect();
            }
        }

        public String GetInput()
        {
            string input = String.Empty;

            while (true)
            {
                try
                {
                    byte[] buf = new byte[1];
                    Int32 recved = this._Connection.Receive(buf);
                    
                    if (recved > 0)
                    {
                        if (buf[0] == '\n' && buffer.Count > 0)
                        {
                            if (buffer[buffer.Count - 1] == '\r')
                                buffer.RemoveAt(buffer.Count - 1);

                            System.Text.UTF8Encoding enc = new System.Text.UTF8Encoding();
                            input = enc.GetString(buffer.ToArray());
                            buffer.Clear();
                            //Return a trimmed string.
                            return input;
                        }
                        else
                            buffer.Add(buf[0]);
                    }
                    else if (recved == 0) //Disconnected
                    {
                        this.Connected = false;
                        this.LoggedIn = false;
                        return "Disconnected.";
                    }
                }
                catch (Exception e)
                {
                    //Flag as disabled 
                    this.Connected = false;
                    this.LoggedIn = false;
                    return e.Message;
                }
            }
        }
        #endregion

        #region Event Methods
        public delegate void OnConnectHandler();
        public event OnConnectHandler OnConnectEvent;
        public void OnConnect()
        {
            //Greet the user with the game information
            this.SendMessage(this.Game.Name);
            this.SendMessage(this.Game.Description);
            this.SendMessage(String.Empty);

            //Log the user in.
            Boolean result = this.ExecuteSilentCommand("Login");

            this.SendMessage(String.Empty);

            //Flags the character as fully logged in.
            //This will automatically invoke the OnLoggedIn method
            //which will present the user with the server MOTD
            this.LoggedIn = result;
            //Provide a blank line between the character loggin info
            //and the characters actual first in-game Command prompt.
            this.SendMessage(String.Empty);

            //Make sure we are logged in.
            if (!this.LoggedIn)
            {
                this.Disconnect();
            }

            this.ExecuteCommand("Look");
        }

        public delegate void OnDisconnectHandler();
        public event OnDisconnectHandler OnDisconnectEvent;
        public void OnDisconnect()
        {
        }

        public delegate void OnLoginHandler();
        public event OnLoginHandler OnLoginEvent;
        public void OnLogin()
        {
            this.SendMessage(this.Game.Server.MOTD);

            //Check to see if this user is the servers owner.
            if (this.Name == this.Game.Server.ServerOwner)
            {
                //Set the role accordingly.
                this.Role = CharacterRoles.Admin;
            }
        }

        public delegate void OnWalkHandler(AvailableTravelDirections direction);
        public event OnWalkHandler OnWalkEvent;
        public void OnWalk(AvailableTravelDirections direction)
        {
            if (this.CurrentRoom.DoorwayExists(direction))
            {
                this.CurrentRoom = this.CurrentRoom.GetDoorway(direction).ArrivalRoom;
            }
            else
                return;
        }

        public delegate void OnLeaveHandler(Room departingRoom, Room targetRoom, AvailableTravelDirections direction);
        public event OnLeaveHandler OnLeaveEvent;
        public void OnLeave(Room departingRoom, Room targetRoom, AvailableTravelDirections direction)
        {
            //This character was forced moved so we have no direction
            if (direction == AvailableTravelDirections.None)
                departingRoom.SendMessageToOccupants(this.Name + " has left the room.", this);
            else
                departingRoom.SendMessageToOccupants(this.Name + " has left the room heading " + direction.ToString(), this);
        }

        public delegate void OnEnterHandler(Room departingRoom, Room targetRoom, AvailableTravelDirections direction);
        public event OnEnterHandler OnEnterEvent;
        public void OnEnter(Room departingRoom, Room targetRoom, AvailableTravelDirections direction)
        {
            //This character was forced moved so we have no direction
            if (direction == AvailableTravelDirections.None)
                targetRoom.SendMessageToOccupants(this.Name + " has entered the room.");
            else
                targetRoom.SendMessageToOccupants(this.Name + " has entered the room from the " + direction.ToString(), this);

            this.ExecuteCommand("Look");
        }
        #endregion

        #region Character Methods
        public void SetRole(StandardCharacter adminCharacter, StandardCharacter subordinateCharacter, CharacterRoles role)
        {
            //Check to make sure the admin character is truly a admin
            //The Server Owner can change anyone characters Roles at any time regardless of the ServerOwners current Role.
            if (adminCharacter.Role == CharacterRoles.Admin || adminCharacter.Name == this.Game.Server.ServerOwner)
            {
                //Do not allow any other Admins on the server to remove the ServerOwner from Admin status.
                //Server owners can not have any other Role but Admin unless they change it themselves.
                if (subordinateCharacter.Name == this.Game.Server.ServerOwner && adminCharacter.Name != this.Game.Server.ServerOwner)
                {
                    //Tell the admin that is attempting to change the server owner that it's not allowed.
                    adminCharacter.SendMessage("You can not change the role of the Master admin.");
                    //Warn the server owner in the event this is a malicious attempt to take over the server.
                    subordinateCharacter.SendMessage(adminCharacter.Name + " attempted to change your server role!");
                    //Exit with no changes.
                    return;
                }
                //This was not the server owner, so change the role.
                else
                {
                    subordinateCharacter.Role = role;
                    subordinateCharacter.SendMessage("Your role was changed to " + role.ToString());
                    adminCharacter.SendMessage("You changed player '" + subordinateCharacter.Name + "' to the role of " + role.ToString());
                }
            }
            else
            {
                adminCharacter.SendMessage("You do not have the rights to perform this command.");
            }
        }

        private CharacterRoles GetRole(String role)
        {
            //Blow all of the available values up into an array.
            Array values = Enum.GetValues(typeof(CharacterRoles));

            //Loop through each available value, converting it into a string.
            foreach (Int32 value in values)
            {
                //Get the string representation of the current value
                String displayName = Enum.GetName(typeof(CharacterRoles), value);

                //Check if this value matches that of the supplied one.
                //If so, return it as a enum
                if (displayName.ToLower() == role.ToLower())
                    return (CharacterRoles)Enum.Parse(typeof(CharacterRoles), displayName);
            }
            return CharacterRoles.Player;
        }
        #endregion

        #region World Methods
        public virtual void Walk(AvailableTravelDirections direction)
        {
            Room r = this.CurrentRoom;

            this.OnWalkEvent(direction);

            //If we didn't go anywhere, do nothing.
            if (this.CurrentRoom == r)
                return;

            OnLeaveEvent(r, this.CurrentRoom, direction);
            OnEnterEvent(r, this.CurrentRoom, direction);
        }

        public virtual void Move(Room room)
        {
            if (this.CurrentRoom != null)
                this.CurrentRoom.SendMessageToOccupants(this.Name + " has left the room.", this);
            
            this.CurrentRoom = room;
            this.CurrentRoom.AddOccupant(this);
            this.CurrentRoom.SendMessageToOccupants(this.Name + " has entered the room.", this);
        }
        #endregion

        private Socket _Connection;
        private StreamReader _Reader;
        private StreamWriter _Writer;
        private Boolean _LoggedIn;
        private List<byte> buffer = new List<byte>();
    }
}