using System;
using System.Linq;

namespace BurnOutSharp.ProtectionType
{
    public class InnoSetup
    {
        // TOOO: Add Inno Setup extraction
        // https://github.com/dscharrer/InnoExtract
        public static string CheckContents(byte[] fileContent, bool includePosition = false)
        {
            // "Inno"
            byte[] check = new byte[] { 0x49, 0x6E, 0x6E, 0x6F };
            if (fileContent.Contains(check, out int position) && position == 0x30)
                return $"Inno Setup {GetVersion(fileContent)}" + (includePosition ? $" (Index {position})" : string.Empty);

            return null;
        }

        private static string GetVersion(byte[] fileContent)
        {
            byte[] signature = new ArraySegment<byte>(fileContent, 0x30, 12).ToArray();

            // "rDlPtS02" + (char)0x87 + "eVx"
            if (signature.SequenceEqual( new byte[] { 0x72, 0x44, 0x6C, 0x50, 0x74, 0x53, 0x30, 0x32, 0x87, 0x65, 0x56, 0x78 }))
                return "1.2.10";

            // "rDlPtS04" + (char)0x87 + "eVx"
            else if (signature.SequenceEqual(new byte[] { 0x72, 0x44, 0x6C, 0x50, 0x74, 0x53, 0x30, 0x34, 0x87, 0x65, 0x56, 0x78 }))
                return "4.0.0";

            // "rDlPtS05" + (char)0x87 + "eVx"
            else if (signature.SequenceEqual(new byte[] { 0x72, 0x44, 0x6C, 0x50, 0x74, 0x53, 0x30, 0x35, 0x87, 0x65, 0x56, 0x78 }))
                return "4.0.3";

            // "rDlPtS06" + (char)0x87 + "eVx"
            else if (signature.SequenceEqual(new byte[] { 0x72, 0x44, 0x6C, 0x50, 0x74, 0x53, 0x30, 0x36, 0x87, 0x65, 0x56, 0x78 }))
                return "4.0.10";

            // "rDlPtS07" + (char)0x87 + "eVx"
            else if (signature.SequenceEqual(new byte[] { 0x72, 0x44, 0x6C, 0x50, 0x74, 0x53, 0x30, 0x37, 0x87, 0x65, 0x56, 0x78 }))
                return "4.1.6";

            // "rDlPtS" + (char)0xcd + (char)0xe6 + (char)0xd7 + "{" + (char)0x0b + "*"
            else if (signature.SequenceEqual(new byte[] { 0x72, 0x44, 0x6C, 0x50, 0x74, 0x53, 0xCD, 0xE6, 0xD7, 0x7B, 0x0b, 0x2A }))
                return "5.1.5";

            // "nS5W7dT" + (char)0x83 + (char)0xaa + (char)0x1b + (char)0x0f + "j"
            else if (signature.SequenceEqual(new byte[] { 0x6E, 0x53, 0x35, 0x57, 0x37, 0x64, 0x54, 0x83, 0xAA, 0x1B, 0x0F, 0x6A }))
                return "5.1.5";

            return string.Empty;
        }
    }
}