using System.Collections.Generic;

using BCnEncoder.Shared;

namespace BCnEncoder.Encoder

{

internal static class ColorVariationGenerator

{

private static readonly int[] variatePatternEp0R = new int[] { 1, 1, 0, 0, -1, 0, 0, -1, 1, -1, 1, 0, 0, -1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 };

private static readonly int[] variatePatternEp0G = new int[] { 1, 0, 1, 0, 0, -1, 0, -1, 1, -1, 0, 1, 0, 0, -1, 0, 0, 0, 0, 0, 0, 0, 0, 0 };

private static readonly int[] variatePatternEp0B = new int[] { 1, 0, 0, 1, 0, 0, -1, -1, 1, -1, 0, 0, 1, 0, 0, -1, 0, 0, 0, 0, 0, 0, 0, 0 };

private static readonly int[] variatePatternEp1R = new int[] { -1, -1, 0, 0, 1, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 1, -1, 1, 0, 0, -1, 0, 0 };

private static readonly int[] variatePatternEp1G = new int[] { -1, 0, -1, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 1, -1, 0, 1, 0, 0, -1, 0 };

private static readonly int[] variatePatternEp1B = new int[] { -1, 0, 0, -1, 0, 0, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 1, -1, 0, 0, 1, 0, 0, -1 };

public static int VarPatternCount => variatePatternEp0R.Length;

public static (ColorRgb565, ColorRgb565) Variate565(ColorRgb565 c0, ColorRgb565 c1, int i)

{

var idx = i % variatePatternEp0R.Length;

var newEp0 = new ColorRgb565();

var newEp1 = new ColorRgb565();

newEp0.RawR = ByteHelper.ClampToByte(c0.RawR + variatePatternEp0R[idx]);

newEp0.RawG = ByteHelper.ClampToByte(c0.RawG + variatePatternEp0G[idx]);

newEp0.RawB = ByteHelper.ClampToByte(c0.RawB + variatePatternEp0B[idx]);

newEp1.RawR = ByteHelper.ClampToByte(c1.RawR + variatePatternEp1R[idx]);

newEp1.RawG = ByteHelper.ClampToByte(c1.RawG + variatePatternEp1G[idx]);

newEp1.RawB = ByteHelper.ClampToByte(c1.RawB + variatePatternEp1B[idx]);

return (newEp0, newEp1);

}

public static ((int, int, int), (int, int, int)) VariateInt((int, int, int) ep0,

(int, int, int) ep1, int i)

{

var idx = i % variatePatternEp0R.Length;

return ((

ep0.Item1 + variatePatternEp0R[idx],

ep0.Item2 + variatePatternEp0G[idx],

ep0.Item3 + variatePatternEp0B[idx]

),

(

ep1.Item1 + variatePatternEp1R[idx],

ep1.Item2 + variatePatternEp1G[idx],

ep1.Item3 + variatePatternEp1B[idx]

));

}

}

}