PKHeX/PKHeX.Core/Util/BinaryCodedDecimal.cs
Kurt 47071b41f3
Refactoring: Span-based value writes and method signatures (#3361)
Existing `get`/`set` logic is flawed in that it doesn't work on Big Endian operating systems, and it allocates heap objects when it doesn't need to.

`System.Buffers.Binary.BinaryPrimitives` in the `System.Memory` NuGet package provides both Little Endian and Big Endian methods to read and write data; all the `get`/`set` operations have been reworked to use this new API. This removes the need for PKHeX's manual `BigEndian` class, as all functions are already covered by the BinaryPrimitives API.

The `StringConverter` has now been rewritten to accept a Span to read from & write to, no longer requiring a temporary StringBuilder.

Other Fixes included:
- The Super Training UI for Gen6 has been reworked according to the latest block structure additions.
- Cloning a Stadium2 Save File now works correctly (opening from the Folder browser list).
- Checksum & Sanity properties removed from parent PKM class, and is now implemented via interface.
2022-01-02 21:35:59 -08:00

53 lines
1.8 KiB
C#

using System;
using System.Runtime.CompilerServices;
namespace PKHeX.Core
{
/// <summary>
/// 4-bit decimal encoding used by some Generation 1 save file values.
/// </summary>
public static class BinaryCodedDecimal
{
/// <summary>
/// Returns a 32-bit signed integer converted from bytes in a Binary Coded Decimal format byte array.
/// </summary>
/// <param name="input">Input byte array to read from.</param>
public static int ToInt32BE(ReadOnlySpan<byte> input)
{
int result = 0;
foreach (var b in input)
PushDigits(ref result, b);
return result;
}
[MethodImpl(MethodImplOptions.AggressiveInlining)]
private static void PushDigits(ref int result, byte b) => result = (result * 100) + (10 * (b >> 4)) + (b & 0xf);
/// <summary>
/// Writes the <see cref="value"/> to the <see cref="data"/> buffer.
/// </summary>
public static void WriteBytesBE(Span<byte> data, int value)
{
for (int i = data.Length - 1; i >= 0; i--, value /= 100)
data[i] = (byte)((((value / 10) % 10) << 4) | (value % 10));
}
/// <inheritdoc cref="ToInt32BE(ReadOnlySpan{byte})"/>
public static int ToInt32LE(ReadOnlySpan<byte> input)
{
int result = 0;
for (int i = input.Length - 1; i >= 0; i--)
PushDigits(ref result, input[i]);
return result;
}
/// <summary>
/// Writes the <see cref="value"/> to the <see cref="data"/> buffer.
/// </summary>
public static void WriteBytesLE(Span<byte> data, int value)
{
for (int i = 0; i < data.Length; i++, value /= 100)
data[i] = (byte)((((value / 10) % 10) << 4) | (value % 10));
}
}
}