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

    File: SJIS.hpp
    Date: 2021-11-1
    Author: Reece
***/
#pragma once

namespace Aurora::Locale::Encoding::SJIS
{
    static auline int GetLenSJISCodePoint(const AuUInt8 *in, AuUInt32 len)
    {
        if (len == 0)
        {
            return 0;
        }

        auto b = in[0];

        if (b >= 0x80)
        {
            if (b <= 0xDF)
            {
                if (len < 2)
                {
                    return 0;
                }

                return 2;
            }
            else if (b <= 0xEF)
            {
                if (len < 3)
                {
                    return 0;
                }

                return 3;
            }
            else
            {
                if (len < 4)
                {
                    return 0;
                }
             
                return 4;
            }

        }
        return 1;
    }

    static inline AuUInt32 CountSJIS(const void *base, AuUInt32 length, bool bytes = false)
    {
        AuUInt32 i {}, cps {};
        
        for (; i < length; )
        {
            auto next = GetLenSJISCodePoint((const AuUInt8 *)base + i, length - i);
            if (next == 0)
            {
                return bytes ? i : cps;
            }
            
            cps++;
            i += next;
        }
        
        return bytes ? i : cps;
    }
}