using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace Novacoin
{
    /// <summary>
    /// Available address types
    /// </summary>
    public enum AddrType
    {
        PUBKEY_ADDRESS = 8,
        SCRIPT_ADDRESS = 20,
        PUBKEY_ADDRESS_TEST = 111,
        SCRIPT_ADDRESS_TEST = 196
    };

    /// <summary>
    /// Represents novacoin address
    /// </summary>
    public class CNovacoinAddress
    {
        private byte nVersion;
        private List<byte> addrData;

        /// <summary>
        /// Initialize with custom data and version
        /// </summary>
        /// <param name="nVersionIn"></param>
        /// <param name="addrDataIn"></param>
        public CNovacoinAddress(byte nVersionIn, IEnumerable<byte> addrDataIn)
        {
            nVersion = nVersionIn;
            addrData = addrDataIn.ToList();
        }

        /// <summary>
        /// Initialize new instance of PUBKEY_ADDRESS
        /// </summary>
        /// <param name="keyID">CKeyID instance</param>
        public CNovacoinAddress(CKeyID keyID)
        {
            nVersion = (byte)AddrType.PUBKEY_ADDRESS;
            addrData = new List<byte>(keyID.hashBytes);
        }

        public CNovacoinAddress(string strNovacoinAddress)
        {
            addrData = AddressTools.Base58DecodeCheck(strNovacoinAddress).ToList();

            nVersion = addrData[0];
            addrData.RemoveAt(0);
        }

        /// <summary>
        /// Initialize new instance of SCRIPT_ADDRESS
        /// </summary>
        /// <param name="keyID">CScriptID instance</param>
        public CNovacoinAddress(CScriptID scriptID)
        {
            nVersion = (byte)AddrType.SCRIPT_ADDRESS;
            addrData = new List<byte>(scriptID.hashBytes);
        }

        /// <summary>
        /// Basic sanity checking
        /// </summary>
        /// <returns></returns>
        public bool IsValid
        {
            get
            {
                // Address data is normally generated by RIPEMD-160 hash function
                int nExpectedSize = 20;

                switch ((AddrType)nVersion)
                {
                    case AddrType.PUBKEY_ADDRESS:
                        nExpectedSize = 20; // Hash of public key
                        break;
                    case AddrType.SCRIPT_ADDRESS:
                        nExpectedSize = 20; // Hash of CScript
                        break;
                    case AddrType.PUBKEY_ADDRESS_TEST:
                        nExpectedSize = 20;
                        break;
                    case AddrType.SCRIPT_ADDRESS_TEST:
                        nExpectedSize = 20;
                        break;
                    default:
                        return false;
                }

                return addrData.Count == nExpectedSize;
            }
        }

        /// <summary>
        /// Generate base58 serialized representation of novacoin address
        /// </summary>
        /// <returns>Base58(data + checksum)</returns>
        public override string ToString()
        {
            List<byte> r = new List<byte>();

            r.Add(nVersion);
            r.AddRange(addrData);

            return AddressTools.Base58EncodeCheck(r);
        }
    }
}