BITKit/Src/Unity/Scripts/UX/Library/ComplexRadialProgress.cs

using System.Linq;
using UnityEngine;
using UnityEngine.UIElements;

namespace BITKit.UX
{

    // An element that displays progress inside a partially filled circle
    public class ComplexRadialProgress : VisualElement
    {
        public new class UxmlTraits : VisualElement.UxmlTraits
        {
            // The progress property is exposed to UXML.
            private readonly UxmlStringAttributeDescription m_ProgressAttribute = new UxmlStringAttributeDescription()
            {
                name = "progress"
            };

            // Use the Init method to assign the value of the progress UXML attribute to the C# progress property.
            public override void Init(VisualElement ve, IUxmlAttributes bag, CreationContext cc)
            {
                base.Init(ve, bag, cc);

                ((ComplexRadialProgress)ve).progress = m_ProgressAttribute.GetValueFromBag(bag, cc);
            }
        }

        // Define a factory class to expose this control to UXML.
        public new class UxmlFactory : UxmlFactory<ComplexRadialProgress, UxmlTraits> { }

        // These are USS class names for the control overall and the label.
        public static readonly string ussClassName = "radial-progress";
        public static readonly string ussLabelClassName = "radial-progress__label";

        private Color[] m_ProgressColor = new Color[]
        {
            Color.red,
            Color.yellow,
            Color.blue, 
            Color.green,
            Color.cyan,
            Color.magenta,
            Color.white,
            Color.blue,
        };

        // This is the label that displays the percentage.
        private Label m_Label;

        // This is the number that the Label displays as a percentage.
        private string m_Progress;

        // A value between 0 and 100
        public string progress
        {
            // The progress property is exposed in C#.
            get => m_Progress;
            set
            {
                // Whenever the progress property changes, MarkDirtyRepaint() is named. This causes a call to the
                // generateVisualContents callback.
                m_Progress = value;
                MarkDirtyRepaint();
            }
        }

        // This default constructor is RadialProgress's only constructor.
        public ComplexRadialProgress()
        {
            // Add the USS class name for the overall control.
            AddToClassList(ussClassName);

            // Register a callback after custom style resolution.
            RegisterCallback<CustomStyleResolvedEvent>(evt => CustomStylesResolved(evt));

            // Register a callback to generate the visual content of the control.
            generateVisualContent += GenerateVisualContent;

            progress = string.Empty;
        }

        private static void CustomStylesResolved(CustomStyleResolvedEvent evt)
        {
            ComplexRadialProgress element = (ComplexRadialProgress)evt.currentTarget;
            element.UpdateCustomStyles();
        }

        // After the custom colors are resolved, this method uses them to color the meshes and (if necessary) repaint
        // the control.
        private void UpdateCustomStyles()
        {
            for (var i = 0; i < 8; i++)
            {
                if (customStyle.TryGetValue(new CustomStyleProperty<Color>($"--progress-color--{i}"), out var color))
                {
                    m_ProgressColor[i] = color;
                }
                else
                {
                    m_ProgressColor[i] = Color.red;
                }
            }
            MarkDirtyRepaint();
        }

        private void GenerateVisualContent(MeshGenerationContext context)
        {
            var width = contentRect.width;
            var height = contentRect.height;

            var painter = context.painter2D;
            painter.lineWidth = 4.0f;
            painter.lineCap = LineCap.Butt;
            
            var tempColor = m_ProgressColor.First();

            // // Draw the track
            // painter.strokeColor = m_TrackColor;
            // painter.BeginPath();
            // painter.Arc(new Vector2(width * 0.5f, height * 0.5f), width * 0.5f - 5 , 0.0f, 360.0f);
            // painter.Stroke();

            var lastEndAngle = -90f;
            var index = 0;
            foreach (var str in progress.Split(","))
            {
                if(float.TryParse(str,out var nextProgress) is false)continue;
                if (nextProgress <= 0) continue;

                var startAngle =lastEndAngle;

                //startAngle = Mathf.Lerp(-90f, 480f, nextProgress);
                
                var endAngle = 360.0f * (nextProgress) + startAngle;

                lastEndAngle = endAngle;

                startAngle +=2;
                endAngle -= 2;
                
                // Draw the progress Out
                painter.strokeColor = m_ProgressColor[index];
                painter.BeginPath();
                painter.Arc(new Vector2(width * 0.5f, height * 0.5f), width * 0.5f, startAngle,endAngle );
                painter.Stroke();
            
        
                // Draw the progress Middle
                tempColor =  m_ProgressColor[index];
                tempColor.a = tempColor.a / 3f * 2f;
                painter.strokeColor = tempColor;
                painter.BeginPath();
                painter.Arc(new Vector2(width * 0.5f, height * 0.5f), width * 0.5f -4f, startAngle, endAngle);
                painter.Stroke();
            
            
                // Draw the progress Inner
                tempColor = m_ProgressColor[index];
                tempColor.a = tempColor.a / 3f * 1f;
                painter.strokeColor = tempColor;
                painter.BeginPath();
                painter.Arc(new Vector2(width * 0.5f, height * 0.5f), width * 0.5f-8f, startAngle, endAngle);
                painter.Stroke();

                index++;
            }
        }
    }
}