using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Controls;
using System.Windows.Ink;
using System.Windows.Input;
using System.Windows.Media;

namespace ECMonitor.PlayerDraw.Code
{

    /// <summary>
    /// 画图类
    /// </summary>
    public class Draw
    {
        /// <summary>
        /// 初始化对象
        /// </summary>
        /// <param name="broad">画布</param>
        public Draw(InkCanvas broad)
        {
            this.broad = broad;

            arcs = new StylusPointCollection[8];
            for (int i = 0; i < arcs.Length; i++)
            {
                arcs[i] = new StylusPointCollection();
            }
        }

        InkCanvas broad;


        public StrokeEx Line(StylusPoint a, StylusPoint b,  int warningLevel)
        {
            StylusPointCollection points = new StylusPointCollection { a, b };
            StrokeEx line = new StrokeEx(points);
            line.DrawType = DrawTypes.线段;
            line.WarningLevel = warningLevel;
            line.DrawingAttributes = broad.DefaultDrawingAttributes.Clone();
            line.DrawingAttributes.Color = BlackboardClass.ChangeColor((ColorEnum)warningLevel);
            return line;
        }

        /// <summary>
        /// 以矩形的两个对角坐标为根据画矩形
        /// </summary>
        /// <param name="a">一个顶点坐标</param>
        /// <param name="c">与a相对点的坐标</param>
        /// <returns></returns>
        public StrokeEx Rectangle(StylusPoint a, StylusPoint c,int warningLevel)
        {
            StylusPoint b = new StylusPoint(c.X, a.Y),
            d = new StylusPoint(a.X, c.Y);
            StylusPointCollection points = new StylusPointCollection { a, b, c, d, a };
            StrokeEx rectangle = new StrokeEx(points);
            rectangle.DrawType = DrawTypes.矩形;
            rectangle.WarningLevel = warningLevel;
            rectangle.DrawingAttributes = broad.DefaultDrawingAttributes.Clone();
            rectangle.DrawingAttributes.StylusTip = StylusTip.Rectangle;
            rectangle.DrawingAttributes.Color = BlackboardClass.ChangeColor((ColorEnum)warningLevel);
            return rectangle;
        }

        
        /// <summary>
        /// 绘制三角形
        /// </summary>
        /// <param name="a">点a</param>
        /// <param name="b">点b</param>
        /// <param name="c">点c</param>
        /// <returns></returns>
        public Stroke Triangle(StylusPoint a, StylusPoint b, StylusPoint c)
        {
            StylusPointCollection points = new StylusPointCollection { a, b, c, a };
            StrokeEx triangle = new StrokeEx(points);
            triangle.DrawType = DrawTypes.三角形;
            triangle.DrawingAttributes = broad.DefaultDrawingAttributes.Clone();
           
            return triangle;
        }

        /// <summary>
        /// 绘制多边形
        /// </summary>
        /// <param name="points">多边形的顶点</param>
        /// <returns></returns>
        public Stroke Polygon(StylusPointCollection points, int warningLevel)
        {
            points.Add(points[0]);
            StrokeEx polygon = new StrokeEx(points);
            polygon.DrawType = DrawTypes.多边形;
            polygon.WarningLevel = warningLevel;
            polygon.DrawingAttributes = broad.DefaultDrawingAttributes.Clone();
            polygon.DrawingAttributes.Color = BlackboardClass.ChangeColor((ColorEnum)warningLevel);
            return polygon;


        }
        public Stroke Lines(StylusPointCollection points, int warningLevel)
        {
             
            StrokeEx polygon = new StrokeEx(points);
            polygon.DrawType = DrawTypes.多边形;
            polygon.WarningLevel = warningLevel;
            polygon.DrawingAttributes = broad.DefaultDrawingAttributes.Clone();
            polygon.DrawingAttributes.Color = BlackboardClass.ChangeColor((ColorEnum)warningLevel);
            return polygon;


        }

        public Stroke Circle(StylusPoint o, StylusPoint p,int warningLevel)
        {
            StylusPointCollection points = OriginalArc(o, p);



            StrokeEx circle = new StrokeEx(points);
            circle.DrawType = DrawTypes.圆;
            circle.WarningLevel = warningLevel;
            circle.DrawingAttributes = broad.DefaultDrawingAttributes.Clone();
            circle.DrawingAttributes.Color = BlackboardClass.ChangeColor((ColorEnum)warningLevel);
            for (int i = 0; i < arcs.Length; i++)
            {
                arcs[i] = new StylusPointCollection();
            }
            return circle;
        }

        private StylusPointCollection OriginalArc(StylusPoint o, StylusPoint p)
        {

            StylusPointCollection points = new StylusPointCollection();

            double r =
                Math.Sqrt(Math.Pow(p.X - o.X, 2) + Math.Pow(p.Y - o.Y, 2));//该圆的半径
            double d = 3 - 2 * r;
            StylusPoint motionPoint = new StylusPoint();
            motionPoint.X = 0;
            motionPoint.Y = r;
            CirclePoints(o, motionPoint);
            while (motionPoint.X < motionPoint.Y)
            {
                if (d < 0)
                    d = d + 4 * motionPoint.X + 6;
                else
                {
                    d = d + 4 * (motionPoint.X - motionPoint.Y) + 10;
                    motionPoint.Y--;

                }
                motionPoint.X++;
                CirclePoints(o, motionPoint);
            }
            for (int i = 0; i < arcs.Length; i++)
            {
                if (i % 2 != 0)
                {
                    for (int index = arcs[i].Count - 1; index >= 0; index--)
                    {
                        points.Add(arcs[i][index]);
                    }
                }
                else
                    points.Add(arcs[i]);
            }
            return points;
        }
        StylusPointCollection[] arcs;//表示一个圆的八个弧

        private void CirclePoints(StylusPoint o, StylusPoint p)
        {
            arcs[0].Add(new StylusPoint(p.X + o.X, p.Y + o.Y));
            arcs[1].Add(new StylusPoint(p.Y + o.X, p.X + o.Y));
            arcs[2].Add(new StylusPoint(-p.Y + o.X, p.X + o.Y));
            arcs[3].Add(new StylusPoint(-p.X + o.X, p.Y + o.Y));
            arcs[4].Add(new StylusPoint(-p.X + o.X, -p.Y + o.Y));
            arcs[5].Add(new StylusPoint(-p.Y + o.X, -p.X + o.Y));
            arcs[6].Add(new StylusPoint(p.Y + o.X, -p.X + o.Y));
            arcs[7].Add(new StylusPoint(p.X + o.X, -p.Y + o.Y));
        }
    }
}
/*
     备注：
 *网上关于“中点画圆法”的弧上点位置的说法只适用于单纯用点画圆，
 而不适用于用线来画圆。
 * 我的方法是，创建一个字段，用来存储圆的坐标，当遇到奇数弧时坐标列表从后往前
 存储。
 */