/*
 * Copyright (c) 2007-2008, openmetaverse.org
 * All rights reserved.
 *
 * - Redistribution and use in source and binary forms, with or without
 *   modification, are permitted provided that the following conditions are met:
 *
 * - Redistributions of source code must retain the above copyright notice, this
 *   list of conditions and the following disclaimer.
 * - Neither the name of the openmetaverse.org nor the names
 *   of its contributors may be used to endorse or promote products derived from
 *   this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "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 THE COPYRIGHT OWNER 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.
 */

using System;
using System.Collections;
using System.Collections.Generic;
using System.Text;

namespace OpenMetaverse.StructuredData
{
    /// <summary>
    /// 
    /// </summary>
    public enum LLSDType
    {
        /// <summary></summary>
        Unknown,
        /// <summary></summary>
        Boolean,
        /// <summary></summary>
        Integer,
        /// <summary></summary>
        Real,
        /// <summary></summary>
        String,
        /// <summary></summary>
        UUID,
        /// <summary></summary>
        Date,
        /// <summary></summary>
        URI,
        /// <summary></summary>
        Binary,
        /// <summary></summary>
        Map,
        /// <summary></summary>
        Array
    }

    /// <summary>
    /// 
    /// </summary>
    public class LLSDException : Exception
    {
        public LLSDException(string message) : base(message) { }
    }

    /// <summary>
    /// 
    /// </summary>
    public partial class LLSD
    {
        public virtual LLSDType Type { get { return LLSDType.Unknown; } }

        public virtual bool AsBoolean() { return false; }
        public virtual int AsInteger() { return 0; }
        public virtual double AsReal() { return 0d; }
        public virtual string AsString() { return String.Empty; }
        public virtual UUID AsUUID() { return UUID.Zero; }
        public virtual DateTime AsDate() { return Utils.Epoch; }
        public virtual Uri AsUri() { return new Uri(String.Empty); }
        public virtual byte[] AsBinary() { return new byte[0]; }

        public override string ToString() { return "undef"; }

        public static LLSD FromBoolean(bool value) { return new LLSDBoolean(value); }
        public static LLSD FromInteger(int value) { return new LLSDInteger(value); }
        public static LLSD FromInteger(uint value) { return new LLSDInteger((int)value); }
        public static LLSD FromInteger(short value) { return new LLSDInteger((int)value); }
        public static LLSD FromInteger(ushort value) { return new LLSDInteger((int)value); }
        public static LLSD FromInteger(sbyte value) { return new LLSDInteger((int)value); }
        public static LLSD FromInteger(byte value) { return new LLSDInteger((int)value); }
        public static LLSD FromReal(double value) { return new LLSDReal(value); }
        public static LLSD FromReal(float value) { return new LLSDReal((double)value); }
        public static LLSD FromString(string value) { return new LLSDString(value); }
        public static LLSD FromUUID(UUID value) { return new LLSDUUID(value); }
        public static LLSD FromDate(DateTime value) { return new LLSDDate(value); }
        public static LLSD FromUri(Uri value) { return new LLSDURI(value); }
        public static LLSD FromBinary(byte[] value) { return new LLSDBinary(value); }
        public static LLSD FromBinary(long value) { return new LLSDBinary(value); }
        public static LLSD FromBinary(ulong value) { return new LLSDBinary(value); }

        public static LLSD FromVector2(Vector2 value)
        {
            LLSDArray array = new LLSDArray();
            array.Add(LLSD.FromReal(value.X));
            array.Add(LLSD.FromReal(value.Y));
            return array;
        }

        public static LLSD FromVector3(Vector3 value)
        {
            LLSDArray array = new LLSDArray();
            array.Add(LLSD.FromReal(value.X));
            array.Add(LLSD.FromReal(value.Y));
            array.Add(LLSD.FromReal(value.Z));
            return array;
        }

        public static LLSD FromVector3d(Vector3d value)
        {
            LLSDArray array = new LLSDArray();
            array.Add(LLSD.FromReal(value.X));
            array.Add(LLSD.FromReal(value.Y));
            array.Add(LLSD.FromReal(value.Z));
            return array;
        }

        public static LLSD FromVector4(Vector4 value)
        {
            LLSDArray array = new LLSDArray();
            array.Add(LLSD.FromReal(value.X));
            array.Add(LLSD.FromReal(value.Y));
            array.Add(LLSD.FromReal(value.Z));
            array.Add(LLSD.FromReal(value.W));
            return array;
        }

        public static LLSD FromQuaternion(Quaternion value)
        {
            LLSDArray array = new LLSDArray();
            array.Add(LLSD.FromReal(value.X));
            array.Add(LLSD.FromReal(value.Y));
            array.Add(LLSD.FromReal(value.Z));
            array.Add(LLSD.FromReal(value.W));
            return array;
        }

        public static LLSD FromColor4(Color4 value)
        {
            LLSDArray array = new LLSDArray();
            array.Add(LLSD.FromReal(value.R));
            array.Add(LLSD.FromReal(value.G));
            array.Add(LLSD.FromReal(value.B));
            array.Add(LLSD.FromReal(value.A));
            return array;
        }

        public static LLSD FromObject(object value)
        {
            if (value == null) { return new LLSD(); }
            else if (value is bool) { return new LLSDBoolean((bool)value); }
            else if (value is int) { return new LLSDInteger((int)value); }
            else if (value is uint) { return new LLSDInteger((int)(uint)value); }
            else if (value is short) { return new LLSDInteger((int)(short)value); }
            else if (value is ushort) { return new LLSDInteger((int)(ushort)value); }
            else if (value is sbyte) { return new LLSDInteger((int)(sbyte)value); }
            else if (value is byte) { return new LLSDInteger((int)(byte)value); }
            else if (value is double) { return new LLSDReal((double)value); }
            else if (value is float) { return new LLSDReal((double)(float)value); }
            else if (value is string) { return new LLSDString((string)value); }
            else if (value is UUID) { return new LLSDUUID((UUID)value); }
            else if (value is DateTime) { return new LLSDDate((DateTime)value); }
            else if (value is Uri) { return new LLSDURI((Uri)value); }
            else if (value is byte[]) { return new LLSDBinary((byte[])value); }
            else if (value is long) { return new LLSDBinary((long)value); }
            else if (value is ulong) { return new LLSDBinary((ulong)value); }
            else if (value is Vector2) { return FromVector2((Vector2)value); }
            else if (value is Vector3) { return FromVector3((Vector3)value); }
            else if (value is Vector3d) { return FromVector3d((Vector3d)value); }
            else if (value is Vector4) { return FromVector4((Vector4)value); }
            else if (value is Quaternion) { return FromQuaternion((Quaternion)value); }
            else if (value is Color4) { return FromColor4((Color4)value); }
            else return new LLSD();
        }
    }

    /// <summary>
    /// 
    /// </summary>
    public class LLSDBoolean : LLSD
    {
        private bool value;

        private static byte[] trueBinary = { 0x31 };
        private static byte[] falseBinary = { 0x30 };

        public override LLSDType Type { get { return LLSDType.Boolean; } }

        public LLSDBoolean(bool value)
        {
            this.value = value;
        }

        public override bool AsBoolean() { return value; }
        public override int AsInteger() { return value ? 1 : 0; }
        public override double AsReal() { return value ? 1d : 0d; }
        public override string AsString() { return value ? "1" : "0"; }
        public override byte[] AsBinary() { return value ? trueBinary : falseBinary; }

        public override string ToString() { return AsString(); }
    }

    /// <summary>
    /// 
    /// </summary>
    public class LLSDInteger : LLSD
    {
        private int value;

        public override LLSDType Type { get { return LLSDType.Integer; } }

        public LLSDInteger(int value)
        {
            this.value = value;
        }

        public override bool AsBoolean() { return value != 0; }
        public override int AsInteger() { return value; }
        public override double AsReal() { return (double)value; }
    
        public override string AsString() { return value.ToString(); }
        
         public override byte[] AsBinary() {
            int bigEndInt = System.Net.IPAddress.HostToNetworkOrder( value );
            byte[] binary = BitConverter.GetBytes(bigEndInt);
            return binary;
        }
                
        public override string ToString() { return AsString(); }        
    }
    
    /// <summary>
    /// 
    /// </summary>
    public class LLSDReal : LLSD
    {
        private double value;

        public override LLSDType Type { get { return LLSDType.Real; } }

        public LLSDReal(double value)
        {
            this.value = value;
        }

        public override bool AsBoolean() { return (!Double.IsNaN(value) && value != 0d); }
        public override int AsInteger() { 
            if ( Double.IsNaN( value ) )
                return 0;
            if ( value > (double)Int32.MaxValue )
                return Int32.MaxValue;
            if ( value < (double)Int32.MinValue )
                return Int32.MinValue;
            return (int)Math.Round( value );
        }
 
        public override double AsReal() { return value; }
        public override string AsString() { return value.ToString(Helpers.EnUsCulture); }
        
        public override byte[] AsBinary() {
            byte[] bytesHostEnd = BitConverter.GetBytes( value );
            long longHostEnd = BitConverter.ToInt64( bytesHostEnd, 0 );
            long longNetEnd = System.Net.IPAddress.HostToNetworkOrder( longHostEnd );
            byte[] bytesNetEnd = BitConverter.GetBytes( longNetEnd );
            return bytesNetEnd;
        }
        public override string ToString() { return AsString(); }
    }

    /// <summary>
    /// 
    /// </summary>
    public class LLSDString : LLSD
    {
        private string value;

        public override LLSDType Type { get { return LLSDType.String; } }

        public LLSDString(string value)
        {
            // Refuse to hold null pointers
            if (value != null)
                this.value = value;
            else
                this.value = String.Empty;
        }

        public override bool AsBoolean()
        {
            if (String.IsNullOrEmpty(value))
                return false;

            if (value == "0" || value.ToLower() == "false")
                return false;

            return true;
        }

        public override int AsInteger()
        {
            double dbl;
            if (Double.TryParse(value, out dbl))
                return (int)Math.Floor( dbl );
            else
                return 0;
        }
        public override double AsReal()
        {
            double dbl;
            if (Double.TryParse(value, out dbl))
                return dbl;
            else
                return 0d;
        }
        public override string AsString() { return value; } 
        public override byte[] AsBinary() { return Encoding.UTF8.GetBytes( value ); }
        public override UUID AsUUID()
        {
            UUID uuid;
            if (UUID.TryParse(value, out uuid))
                return uuid;
            else
                return UUID.Zero;
        }
        public override DateTime AsDate()
        {
            DateTime dt;
            if (DateTime.TryParse(value, out dt))
                return dt;
            else
                return Utils.Epoch;
        }
        public override Uri AsUri() { return new Uri(value); }

        public override string ToString() { return AsString(); }
    }

    /// <summary>
    /// 
    /// </summary>
    public class LLSDUUID : LLSD
    {
        private UUID value;

        public override LLSDType Type { get { return LLSDType.UUID; } }

        public LLSDUUID(UUID value)
        {
            this.value = value;
        }

        public override bool AsBoolean() { return (value == UUID.Zero) ? false : true; }
        public override string AsString() { return value.ToString(); }
        public override UUID AsUUID() { return value; }
        public override byte[] AsBinary() { return value.GetBytes(); }
        public override string ToString() { return AsString(); }
    }

    /// <summary>
    /// 
    /// </summary>
    public class LLSDDate : LLSD
    {
        private DateTime value;

        public override LLSDType Type { get { return LLSDType.Date; } }

        public LLSDDate(DateTime value)
        {
            this.value = value;
        }

        public override string AsString() 
        { 
            string format;
            if ( value.Millisecond > 0 )
                format = "yyyy-MM-ddTHH:mm:ss.ffZ";
            else
                format = "yyyy-MM-ddTHH:mm:ssZ";
            return value.ToUniversalTime().ToString( format );        
        }
        
         public override byte[] AsBinary() {
            TimeSpan ts = value.ToUniversalTime() - new DateTime( 1970, 1, 1, 0, 0, 0, DateTimeKind.Utc );
            double timestamp =  (double)ts.TotalSeconds;
            byte[] bytesHostEnd = BitConverter.GetBytes( timestamp );
            long longHostEnd = BitConverter.ToInt64( bytesHostEnd, 0 );
            long longNetEnd = System.Net.IPAddress.HostToNetworkOrder( longHostEnd );
            byte[] bytesNetEnd = BitConverter.GetBytes( longNetEnd );
            return bytesNetEnd;
        }

        public override DateTime AsDate() { return value; }
        public override string ToString() { return AsString(); }
    }

    /// <summary>
    /// 
    /// </summary>
    public class LLSDURI : LLSD
    {
        private Uri value;

        public override LLSDType Type { get { return LLSDType.URI; } }

        public LLSDURI(Uri value)
        {
            this.value = value;
        }

        public override string AsString() { return value.ToString(); }
        public override Uri AsUri() { return value; }
        public override byte[] AsBinary() { return Encoding.UTF8.GetBytes(value.ToString()); }
        public override string ToString() { return AsString(); }
    }

    /// <summary>
    /// 
    /// </summary>
    public class LLSDBinary : LLSD
    {
        private byte[] value;

        public override LLSDType Type { get { return LLSDType.Binary; } }

        public LLSDBinary(byte[] value)
        {
            if (value != null)
                this.value = value;
            else
                this.value = new byte[0];
        }

        public LLSDBinary(long value)
        {
            this.value = BitConverter.GetBytes(value);
        }

        public LLSDBinary(ulong value)
        {
            this.value = BitConverter.GetBytes(value);
        }

        public override string AsString() { return Convert.ToBase64String(value); }
        public override byte[] AsBinary() { return value; }

        public override string ToString()
        {
            // TODO: ToString() is only meant for friendly display, a hex string would
            // be more friendly then a base64 string
            return AsString();
        }
    }

    /// <summary>
    /// 
    /// </summary>
    public class LLSDMap : LLSD, IDictionary<string, LLSD>
    {
        private Dictionary<string, LLSD> value;

        public override LLSDType Type { get { return LLSDType.Map; } }

        public LLSDMap()
        {
            value = new Dictionary<string, LLSD>();
        }

        public LLSDMap(int capacity)
        {
            value = new Dictionary<string, LLSD>(capacity);
        }

        public LLSDMap(Dictionary<string, LLSD> value)
        {
            if (value != null)
                this.value = value;
            else
                this.value = new Dictionary<string, LLSD>();
        }

        public override bool AsBoolean() { return value.Count > 0; }

        public override string ToString()
        {
            return LLSDParser.SerializeNotationFormatted(this);
        }

        #region IDictionary Implementation

        public int Count { get { return value.Count; } }
        public bool IsReadOnly { get { return false; } }
        public ICollection<string> Keys { get { return value.Keys; } }
        public ICollection<LLSD> Values { get { return value.Values; } }
        public LLSD this[string key]
        {
            get
            {
                LLSD llsd;
                if (this.value.TryGetValue(key, out llsd))
                    return llsd;
                else
                    return new LLSD();
            }
            set { this.value[key] = value; }
        }

        public bool ContainsKey(string key)
        {
            return value.ContainsKey(key);
        }

        public void Add(string key, LLSD llsd)
        {
            value.Add(key, llsd);
        }

        public void Add(KeyValuePair<string, LLSD> kvp)
        {
            value.Add(kvp.Key, kvp.Value);
        }

        public bool Remove(string key)
        {
            return value.Remove(key);
        }

        public bool TryGetValue(string key, out LLSD llsd)
        {
            return value.TryGetValue(key, out llsd);
        }

        public void Clear()
        {
            value.Clear();
        }

        public bool Contains(KeyValuePair<string, LLSD> kvp)
        {
            // This is a bizarre function... we don't really implement it
            // properly, hopefully no one wants to use it
            return value.ContainsKey(kvp.Key);
        }

        public void CopyTo(KeyValuePair<string, LLSD>[] array, int index)
        {
            throw new NotImplementedException();
        }

        public bool Remove(KeyValuePair<string, LLSD> kvp)
        {
            return this.value.Remove(kvp.Key);
        }

        public System.Collections.IDictionaryEnumerator GetEnumerator()
        {
            return value.GetEnumerator();
        }

        IEnumerator<KeyValuePair<string, LLSD>> IEnumerable<KeyValuePair<string, LLSD>>.GetEnumerator()
        {
            return null;
        }

        IEnumerator IEnumerable.GetEnumerator()
        {
            return value.GetEnumerator();
        }

        #endregion IDictionary Implementation
    }

    /// <summary>
    /// 
    /// </summary>
    public class LLSDArray : LLSD, IList<LLSD>
    {
        private List<LLSD> value;

        public override LLSDType Type { get { return LLSDType.Array; } }

        public LLSDArray()
        {
            value = new List<LLSD>();
        }

        public LLSDArray(int capacity)
        {
            value = new List<LLSD>(capacity);
        }

        public LLSDArray(List<LLSD> value)
        {
            if (value != null)
                this.value = value;
            else
                this.value = new List<LLSD>();
        }

        public Vector2 AsVector2()
        {
            Vector2 vector = Vector2.Zero;

            if (this.Count == 2)
            {
                vector.X = (float)this[0].AsReal();
                vector.Y = (float)this[1].AsReal();
            }

            return vector;
        }

        public Vector3 AsVector3()
        {
            Vector3 vector = Vector3.Zero;

            if (this.Count == 3)
            {
                vector.X = (float)this[0].AsReal();
                vector.Y = (float)this[1].AsReal();
                vector.Z = (float)this[2].AsReal();
            }

            return vector;
        }

        public Vector3d AsVector3d()
        {
            Vector3d vector = Vector3d.Zero;

            if (this.Count == 3)
            {
                vector.X = this[0].AsReal();
                vector.Y = this[1].AsReal();
                vector.Z = this[2].AsReal();
            }

            return vector;
        }

        public Vector4 AsVector4()
        {
            Vector4 vector = Vector4.Zero;

            if (this.Count == 4)
            {
                vector.X = (float)this[0].AsReal();
                vector.Y = (float)this[1].AsReal();
                vector.Z = (float)this[2].AsReal();
                vector.W = (float)this[3].AsReal();
            }

            return vector;
        }

        public Quaternion AsQuaternion()
        {
            Quaternion quaternion = Quaternion.Identity;

            if (this.Count == 4)
            {
                quaternion.X = (float)this[0].AsReal();
                quaternion.Y = (float)this[1].AsReal();
                quaternion.Z = (float)this[2].AsReal();
                quaternion.W = (float)this[3].AsReal();
            }

            return quaternion;
        }

        public Color4 AsColor4()
        {
            Color4 color = Color4.Black;

            if (this.Count == 4)
            {
                color.R = (float)this[0].AsReal();
                color.G = (float)this[1].AsReal();
                color.B = (float)this[2].AsReal();
                color.A = (float)this[3].AsReal();
            }

            return color;
        }

        public override bool AsBoolean() { return value.Count > 0; }

        public override string ToString()
        {
            return LLSDParser.SerializeNotationFormatted(this);
        }

        #region IList Implementation

        public int Count { get { return value.Count; } }
        public bool IsReadOnly { get { return false; } }
        public LLSD this[int index]
        {
            get { return value[index]; }
            set { this.value[index] = value; }
        }

        public int IndexOf(LLSD llsd)
        {
            return value.IndexOf(llsd);
        }

        public void Insert(int index, LLSD llsd)
        {
            value.Insert(index, llsd);
        }

        public void RemoveAt(int index)
        {
            value.RemoveAt(index);
        }

        public void Add(LLSD llsd)
        {
            value.Add(llsd);
        }

        public void Add(string str)
        {
            // This is so common that we throw a little helper in here
            value.Add(LLSD.FromString(str));
        }

        public void Clear()
        {
            value.Clear();
        }

        public bool Contains(LLSD llsd)
        {
            return value.Contains(llsd);
        }

        public bool Contains(string element)
        {
            for (int i = 0; i < value.Count; i++)
            {
                if (value[i].Type == LLSDType.String && value[i].AsString() == element)
                    return true;
            }

            return false;
        }

        public void CopyTo(LLSD[] array, int index)
        {
            throw new NotImplementedException();
        }

        public bool Remove(LLSD llsd)
        {
            return value.Remove(llsd);
        }

        IEnumerator IEnumerable.GetEnumerator()
        {
            return value.GetEnumerator();
        }

        IEnumerator<LLSD> IEnumerable<LLSD>.GetEnumerator()
        {
            return value.GetEnumerator();
        }

        #endregion IList Implementation
    }
}