/*
 *
 *    Copyright (c) 2020-2021 Project CHIP Authors
 *    Copyright (c) 2013-2017 Nest Labs, Inc.
 *    All rights reserved.
 *
 *    Licensed under the Apache License, Version 2.0 (the "License");
 *    you may not use this file except in compliance with the License.
 *    You may obtain a copy of the License at
 *
 *        http://www.apache.org/licenses/LICENSE-2.0
 *
 *    Unless required by applicable law or agreed to in writing, software
 *    distributed under the License is distributed on an "AS IS" BASIS,
 *    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *    See the License for the specific language governing permissions and
 *    limitations under the License.
 */

/**
 *    @file
 *      This file implements methods for manipulating for writing
 *      Abstract Syntax Notation One (ASN.1) Object Identifiers
 *      (OIDs).
 *
 */

#include <stdint.h>
#include <stdlib.h>
#include <string.h>

#include <lib/support/DLLUtil.h>
#include <lib/support/SafeInt.h>

#define ASN1_DEFINE_OID_TABLE
#define ASN1_DEFINE_OID_NAME_TABLE
#include <lib/asn1/ASN1.h>

namespace chip {
namespace ASN1 {

DLL_EXPORT OID ParseObjectID(const uint8_t * encodedOID, uint16_t encodedOIDLen)
{
    if (encodedOID == nullptr or encodedOIDLen == 0)
    {
        return kOID_NotSpecified;
    }

    for (const auto & tableEntry : sOIDTable)
    {
        if (encodedOIDLen == tableEntry.EncodedOIDLen && memcmp(encodedOID, tableEntry.EncodedOID, encodedOIDLen) == 0)
        {
            return tableEntry.EnumVal;
        }
    }

    return kOID_Unknown;
}

bool GetEncodedObjectID(OID oid, const uint8_t *& encodedOID, uint16_t & encodedOIDLen)
{
    for (const auto & tableEntry : sOIDTable)
    {
        if (oid == tableEntry.EnumVal)
        {
            encodedOID    = tableEntry.EncodedOID;
            encodedOIDLen = tableEntry.EncodedOIDLen;
            return true;
        }
    }

    return false;
}

OIDCategory GetOIDCategory(OID oid)
{
    if (oid == kOID_Unknown)
    {
        return kOIDCategory_Unknown;
    }
    if (oid == kOID_NotSpecified)
    {
        return kOIDCategory_NotSpecified;
    }
    return static_cast<OIDCategory>(oid & kOIDCategory_Mask);
}

const char * GetOIDName(OID oid)
{
    if (oid == kOID_Unknown)
    {
        return "Unknown";
    }
    if (oid == kOID_NotSpecified)
    {
        return "NotSpecified";
    }
    for (const auto & tableEntry : sOIDNameTable)
    {
        if (oid == tableEntry.EnumVal)
        {
            return tableEntry.Name;
        }
    }
    return "Unknown";
}

CHIP_ERROR ASN1Reader::GetObjectId(OID & oid)
{
    VerifyOrReturnError(Value != nullptr, ASN1_ERROR_INVALID_STATE);
    VerifyOrReturnError(ValueLen >= 1, ASN1_ERROR_INVALID_ENCODING);
    VerifyOrReturnError(mElemStart + mHeadLen + ValueLen <= mContainerEnd, ASN1_ERROR_UNDERRUN);
    VerifyOrReturnError(CanCastTo<uint16_t>(ValueLen), ASN1_ERROR_INVALID_ENCODING);
    oid = ParseObjectID(Value, static_cast<uint16_t>(ValueLen));
    return CHIP_NO_ERROR;
}

CHIP_ERROR ASN1Writer::PutObjectId(OID oid)
{
    const uint8_t * encodedOID;
    uint16_t encodedOIDLen;

    VerifyOrReturnError(GetEncodedObjectID(oid, encodedOID, encodedOIDLen), ASN1_ERROR_UNKNOWN_OBJECT_ID);

    return PutObjectId(encodedOID, encodedOIDLen);
}

} // namespace ASN1
} // namespace chip