/***
    Copyright (C) 2021 J Reece Wilson (a/k/a "Reece"). All rights reserved.

    File: ECCCurves.cpp
    Date: 2021-9-17
    Author: Reece
***/
#include <Source/RuntimeInternal.hpp>
#include "ECC.hpp"
#include "ECCCurves.hpp"
#include "ECCGeneric.hpp"
#include <tomcrypt.h>

namespace Aurora::Crypto::ECC
{
    static const ltc_ecc_curve kNistp256 =
    {
        /* prime    */ "FFFFFFFF00000001000000000000000000000000FFFFFFFFFFFFFFFFFFFFFFFF",
        /* A        */ "FFFFFFFF00000001000000000000000000000000FFFFFFFFFFFFFFFFFFFFFFFC",
        /* B        */ "5AC635D8AA3A93E7B3EBBD55769886BC651D06B0CC53B0F63BCE3C3E27D2604B",
        /* order    */ "FFFFFFFF00000000FFFFFFFFFFFFFFFFBCE6FAADA7179E84F3B9CAC2FC632551",
        /* Gx       */ "6B17D1F2E12C4247F8BCE6E563A440F277037D812DEB33A0F4A13945D898C296",
        /* Gy       */ "4FE342E2FE1A7F9B8EE7EB4A7C0F9E162BCE33576B315ECECBB6406837BF51F5",
        /* cofactor */ 1,
        /* OID      */ "1.2.840.10045.3.1.7"
    };
    
    static const ltc_ecc_curve kNistp384 =
    {
        /* prime    */ "FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEFFFFFFFF0000000000000000FFFFFFFF",
        /* A        */ "FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEFFFFFFFF0000000000000000FFFFFFFC",
        /* B        */ "B3312FA7E23EE7E4988E056BE3F82D19181D9C6EFE8141120314088F5013875AC656398D8A2ED19D2A85C8EDD3EC2AEF",
        /* order    */ "FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFC7634D81F4372DDF581A0DB248B0A77AECEC196ACCC52973",
        /* Gx       */ "AA87CA22BE8B05378EB1C71EF320AD746E1D3B628BA79B9859F741E082542A385502F25DBF55296C3A545E3872760AB7",
        /* Gy       */ "3617DE4A96262C6F5D9E98BF9292DC29F8F41DBD289A147CE9DA3113B5F0B8C00A60B1CE1D7E819D7A431D7C90EA0E5F",
        /* cofactor */ 1,
        /* OID      */ "1.3.132.0.34"
    };

    static const ltc_ecc_curve kNistp521 =
    {
        /* prime    */ "01FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF",
        /* A        */ "01FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFC",
        /* B        */ "0051953EB9618E1C9A1F929A21A0B68540EEA2DA725B99B315F3B8B489918EF109E156193951EC7E937B1652C0BD3BB1BF073573DF883D2C34F1EF451FD46B503F00",
        /* order    */ "01FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFA51868783BF2F966B7FCC0148F709A5D03BB5C9B8899C47AEBB6FB71E91386409",
        /* Gx       */ "00C6858E06B70404E9CD9E3ECB662395B4429C648139053FB521F828AF606B4D3DBAA14B5E77EFE75928FE1DC127A2FFA8DE3348B3C1856A429BF97E7E31C2E5BD66",
        /* Gy       */ "011839296A789A3BC0045C8A5FB42C7D1BD998F54449579B446817AFBD17273E662C97EE72995EF42640C550B9013FAD0761353C7086A272C24088BE94769FD16650",
        /* cofactor */ 1,
        /* OID      */ "1.3.132.0.35"
    };
    
    static const EECCCurve      kEccTypes[]  = {EECCCurve::eCurve256, EECCCurve::eCurve384, EECCCurve::eCurve521};
    static const ltc_ecc_curve *kEccCurves[] = {&kNistp256, &kNistp384, &kNistp521};
    
    EECCCurve OIDToCurve(unsigned long *oid, unsigned long oidlen)
    {
        char tempAgain[256];
        unsigned long size = AuArraySize(tempAgain);
        
        if (pk_oid_num_to_str(oid, oidlen, tempAgain, &size) != CRYPT_OK)
        {
            return {};
        }
        
        // TODO: EVIL
        auto evil = AuString(tempAgain, tempAgain + size);

        for (AU_ITERATE_ARRAY(i, kEccCurves))
        {
            if (kEccCurves[i]->OID == evil)
            {
                return kEccTypes[i];
            }
        }

        return EECCCurve::eEnumInvalid;
    }

    AuOptional<const ltc_ecc_curve *> GetECCCurve(unsigned long *oid, unsigned long oidlen)
    {
        char tempAgain[256];
        unsigned long size = AuArraySize(tempAgain);
        
        if (pk_oid_num_to_str(oid, oidlen, tempAgain, &size) != CRYPT_OK)
        {
            return {};
        }

        // TODO: EVIL
        return GetECCCurve(AuString(tempAgain, tempAgain + size));
    }

    AuOptional<const ltc_ecc_curve *> GetECCCurve(const AuString &oid)
    {

        for (AU_ITERATE_ARRAY(i, kEccCurves))
        {
            if (kEccCurves[i]->OID == oid)
            {
                return kEccCurves[i];
            }
        }
     
        return {};
    }

    AuOptional<const ltc_ecc_curve *> GetECCCurve(EECCCurve curve)
    {
        // TODO: consider using ecc_find_curve, it's basically the same thing with strings
        switch (curve)
        {
        case EECCCurve::eCurve256:
            return &kNistp256;
        case EECCCurve::eCurve384:
            return &kNistp384;
        case EECCCurve::eCurve521:
            return &kNistp521;
        default:
            return {};
        }
    }
}