// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.
 
#pragma warning disable SA1028 // ignore whitespace warnings for generated code
using System;
using System.Collections.Generic;
using System.Formats.Asn1;
using System.Runtime.InteropServices;
 
namespace System.Security.Cryptography.Pkcs.Asn1
{
    [StructLayout(LayoutKind.Sequential)]
    internal partial struct SignedDataAsn
    {
        internal int Version;
        internal System.Security.Cryptography.Asn1.AlgorithmIdentifierAsn[] DigestAlgorithms;
        internal System.Security.Cryptography.Pkcs.Asn1.EncapsulatedContentInfoAsn EncapContentInfo;
        internal System.Security.Cryptography.Pkcs.Asn1.CertificateChoiceAsn[]? CertificateSet;
        internal ReadOnlyMemory<byte>[]? Crls;
        internal System.Security.Cryptography.Pkcs.Asn1.SignerInfoAsn[] SignerInfos;
 
        internal readonly void Encode(AsnWriter writer)
        {
            Encode(writer, Asn1Tag.Sequence);
        }
 
        internal readonly void Encode(AsnWriter writer, Asn1Tag tag)
        {
            writer.PushSequence(tag);
 
            writer.WriteInteger(Version);
 
            writer.PushSetOf();
            for (int i = 0; i < DigestAlgorithms.Length; i++)
            {
                DigestAlgorithms[i].Encode(writer);
            }
            writer.PopSetOf();
 
            EncapContentInfo.Encode(writer);
 
            if (CertificateSet != null)
            {
 
                writer.PushSetOf(new Asn1Tag(TagClass.ContextSpecific, 0));
                for (int i = 0; i < CertificateSet.Length; i++)
                {
                    CertificateSet[i].Encode(writer);
                }
                writer.PopSetOf(new Asn1Tag(TagClass.ContextSpecific, 0));
 
            }
 
 
            if (Crls != null)
            {
 
                writer.PushSetOf(new Asn1Tag(TagClass.ContextSpecific, 1));
                for (int i = 0; i < Crls.Length; i++)
                {
                    try
                    {
                        writer.WriteEncodedValue(Crls[i].Span);
                    }
                    catch (ArgumentException e)
                    {
                        throw new CryptographicException(SR.Cryptography_Der_Invalid_Encoding, e);
                    }
                }
                writer.PopSetOf(new Asn1Tag(TagClass.ContextSpecific, 1));
 
            }
 
 
            writer.PushSetOf();
            for (int i = 0; i < SignerInfos.Length; i++)
            {
                SignerInfos[i].Encode(writer);
            }
            writer.PopSetOf();
 
            writer.PopSequence(tag);
        }
 
        internal static SignedDataAsn Decode(ReadOnlyMemory<byte> encoded, AsnEncodingRules ruleSet)
        {
            return Decode(Asn1Tag.Sequence, encoded, ruleSet);
        }
 
        internal static SignedDataAsn Decode(Asn1Tag expectedTag, ReadOnlyMemory<byte> encoded, AsnEncodingRules ruleSet)
        {
            try
            {
                AsnValueReader reader = new AsnValueReader(encoded.Span, ruleSet);
 
                DecodeCore(ref reader, expectedTag, encoded, out SignedDataAsn decoded);
                reader.ThrowIfNotEmpty();
                return decoded;
            }
            catch (AsnContentException e)
            {
                throw new CryptographicException(SR.Cryptography_Der_Invalid_Encoding, e);
            }
        }
 
        internal static void Decode(ref AsnValueReader reader, ReadOnlyMemory<byte> rebind, out SignedDataAsn decoded)
        {
            Decode(ref reader, Asn1Tag.Sequence, rebind, out decoded);
        }
 
        internal static void Decode(ref AsnValueReader reader, Asn1Tag expectedTag, ReadOnlyMemory<byte> rebind, out SignedDataAsn decoded)
        {
            try
            {
                DecodeCore(ref reader, expectedTag, rebind, out decoded);
            }
            catch (AsnContentException e)
            {
                throw new CryptographicException(SR.Cryptography_Der_Invalid_Encoding, e);
            }
        }
 
        private static void DecodeCore(ref AsnValueReader reader, Asn1Tag expectedTag, ReadOnlyMemory<byte> rebind, out SignedDataAsn decoded)
        {
            decoded = default;
            AsnValueReader sequenceReader = reader.ReadSequence(expectedTag);
            AsnValueReader collectionReader;
            ReadOnlySpan<byte> rebindSpan = rebind.Span;
            int offset;
            ReadOnlySpan<byte> tmpSpan;
 
 
            if (!sequenceReader.TryReadInt32(out decoded.Version))
            {
                sequenceReader.ThrowIfNotEmpty();
            }
 
 
            // Decode SEQUENCE OF for DigestAlgorithms
            {
                collectionReader = sequenceReader.ReadSetOf();
                var tmpList = new List<System.Security.Cryptography.Asn1.AlgorithmIdentifierAsn>();
                System.Security.Cryptography.Asn1.AlgorithmIdentifierAsn tmpItem;
 
                while (collectionReader.HasData)
                {
                    System.Security.Cryptography.Asn1.AlgorithmIdentifierAsn.Decode(ref collectionReader, rebind, out tmpItem);
                    tmpList.Add(tmpItem);
                }
 
                decoded.DigestAlgorithms = tmpList.ToArray();
            }
 
            System.Security.Cryptography.Pkcs.Asn1.EncapsulatedContentInfoAsn.Decode(ref sequenceReader, rebind, out decoded.EncapContentInfo);
 
            if (sequenceReader.HasData && sequenceReader.PeekTag().HasSameClassAndValue(new Asn1Tag(TagClass.ContextSpecific, 0)))
            {
 
                // Decode SEQUENCE OF for CertificateSet
                {
                    collectionReader = sequenceReader.ReadSetOf(new Asn1Tag(TagClass.ContextSpecific, 0));
                    var tmpList = new List<System.Security.Cryptography.Pkcs.Asn1.CertificateChoiceAsn>();
                    System.Security.Cryptography.Pkcs.Asn1.CertificateChoiceAsn tmpItem;
 
                    while (collectionReader.HasData)
                    {
                        System.Security.Cryptography.Pkcs.Asn1.CertificateChoiceAsn.Decode(ref collectionReader, rebind, out tmpItem);
                        tmpList.Add(tmpItem);
                    }
 
                    decoded.CertificateSet = tmpList.ToArray();
                }
 
            }
 
 
            if (sequenceReader.HasData && sequenceReader.PeekTag().HasSameClassAndValue(new Asn1Tag(TagClass.ContextSpecific, 1)))
            {
 
                // Decode SEQUENCE OF for Crls
                {
                    collectionReader = sequenceReader.ReadSetOf(new Asn1Tag(TagClass.ContextSpecific, 1));
                    var tmpList = new List<ReadOnlyMemory<byte>>();
                    ReadOnlyMemory<byte> tmpItem;
 
                    while (collectionReader.HasData)
                    {
                        tmpSpan = collectionReader.ReadEncodedValue();
                        tmpItem = rebindSpan.Overlaps(tmpSpan, out offset) ? rebind.Slice(offset, tmpSpan.Length) : tmpSpan.ToArray();
                        tmpList.Add(tmpItem);
                    }
 
                    decoded.Crls = tmpList.ToArray();
                }
 
            }
 
 
            // Decode SEQUENCE OF for SignerInfos
            {
                collectionReader = sequenceReader.ReadSetOf();
                var tmpList = new List<System.Security.Cryptography.Pkcs.Asn1.SignerInfoAsn>();
                System.Security.Cryptography.Pkcs.Asn1.SignerInfoAsn tmpItem;
 
                while (collectionReader.HasData)
                {
                    System.Security.Cryptography.Pkcs.Asn1.SignerInfoAsn.Decode(ref collectionReader, rebind, out tmpItem);
                    tmpList.Add(tmpItem);
                }
 
                decoded.SignerInfos = tmpList.ToArray();
            }
 
 
            sequenceReader.ThrowIfNotEmpty();
        }
    }
}