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