// Copyright (c) Microsoft Corporation
// The Microsoft Corporation licenses this file to you under the MIT license.
// See the LICENSE file in the project root for more information.

using System;

using Color = System.Windows.Media.Color;

namespace Wpf.Ui.Extend.Controls;

public static class HsvColor
{
    public static Color[] GetSpectrum()
    {
        var rgbs = new Color[360];
        
        for (var h = 0; h < 360; h++)
        {
            rgbs[h] = RgbFromHsv(h, 1f, 1f);
        }
        
        return rgbs;
    }
    
    public static Color[] HueSpectrum(double saturation, double value)
    {
        var rgbs = new Color[7];
        
        for (var h = 0; h < 7; h++)
        {
            rgbs[h] = RgbFromHsv(h * 60, saturation, value);
        }
        
        return rgbs;
    }
    
    public static Color RgbFromHsv(double h, double s, double v)
    {
        if (h > 360 || h < 0 || s > 1 || s < 0 || v > 1 || v < 0)
        {
            return Color.FromRgb(0, 0, 0);
        }
        
        var c = v * s;
        var x = c * (1 - Math.Abs(((h / 60) % 2) - 1));
        var m = v - c;
        
        double r = 0, g = 0, b = 0;
        
        if (h < 60)
        {
            r = c;
            g = x;
        }
        else if (h < 120)
        {
            r = x;
            g = c;
        }
        else if (h < 180)
        {
            g = c;
            b = x;
        }
        else if (h < 240)
        {
            g = x;
            b = c;
        }
        else if (h < 300)
        {
            r = x;
            b = c;
        }
        else if (h <= 360)
        {
            r = c;
            b = x;
        }
        
        return Color.FromRgb((byte)((r + m) * 255), (byte)((g + m) * 255), (byte)((b + m) * 255));
    }
}