// /**
//  * File: Sequence.cs
//  * Author: haraldwolff
//  *
//  * This file and it's content is copyrighted by the Author and / or copyright holder.
//  * Any use wihtout proper permission is illegal and may lead to legal actions.
//  *
//  *
//  **/
using System;
using System.Collections.Generic;
using System.Linq;
using System.IO;
using System.Text;
using ln.snmp.asn1;

namespace ln.snmp.types
{
    public class Sequence : AbstractSequence
    {
        private List<Variable> items = new List<Variable>();

        public Sequence()
            :base(new Identifier(IdentifierClass.UNIVERSAL,true,0x10))
        { }

        public Sequence(IEnumerable<Variable> variables)
            :this()
        {
            foreach (Variable variable in variables)
                Add(variable);
        }

        public override Variable[] Items {
            get => items.ToArray();
            set
            {
                items = new List<Variable>(value);
            }
        }
        public override void Add(Variable item)
        {
            this.items.Add(item);
        }
        public override void Remove(Variable item)
        {
            this.items.Remove(item);
        }
        public override void Remove(int n)
        {
            this.items.RemoveAt(n);
        }
    }

    public abstract class AbstractSequence : Variable
    {
        protected AbstractSequence(Identifier identifier)
            :base(identifier)
        {
        }


        /* Items */
        public abstract Variable[] Items { get; set; }
        public abstract void Add(Variable item);
        public abstract void Remove(Variable item);
        public virtual void Remove(int n)
        {
            Remove(Items[n]);
        }
        public virtual void RemoveAll()
        {
            foreach (Variable item in Items)
                Remove(item);
        }

        /* SNMP Variable */
        public override object Value {
            get => Items;
            set => throw new NotImplementedException();
        }
        public override byte[] Bytes
        {
            get
            {
                MemoryStream stream = new MemoryStream();

                foreach (byte[] binaryItem in Items.Select((x) => (ASN1Value)x).Select((asn1) => asn1.AsByteArray).ToArray())
                {
                    stream.Write(binaryItem, 0, binaryItem.Length);
                }

                return stream.ToArray();
            }
            set
            {
                List<ASN1Value> items = new List<ASN1Value>();
                MemoryStream stream = new MemoryStream(value);

                while (stream.Position < stream.Length)
                {
                    items.Add(new ASN1Value(stream));
                }
                Items = items.Select((x) => (Variable)x).ToArray();
            }
        }

        public override string ToString()
        {
            return string.Format("[{1} {0}]",String.Join(", ",Items.Select((x) => x?.ToString())),GetType().Name);
        }

    }
}