using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Drawing;
using System.Data;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
using System.Drawing.Drawing2D;

namespace PaintDotNet.CustomControl
{
    public partial class TriangleButton : UserControl
    {
        public TriangleButton()
        {
            InitializeComponent();
        }

        /// <summary> 
        /// 必需的设计器变量。
        /// </summary>
        private System.ComponentModel.IContainer components = null;

        /// <summary> 
        /// 清理所有正在使用的资源。
        /// </summary>
        /// <param name="disposing">如果应释放托管资源，为 true；否则为 false。</param>
        protected override void Dispose(bool disposing)
        {
            if (disposing && (components != null))
            {
                components.Dispose();
            }
            base.Dispose(disposing);
        }

        #region 组件设计器生成的代码

        /// <summary> 
        /// 设计器支持所需的方法 - 不要修改
        /// 使用代码编辑器修改此方法的内容。
        /// </summary>
        private void InitializeComponent()
        {
            components = new System.ComponentModel.Container();
            this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font;

            this.SuspendLayout();
            // 
            // TriangleButton
            // 
            this.Name = "TriangleButton";
            this.ResumeLayout(false);
        }

        #endregion

        private Point lastTrackingMouseXY = new Point(-1, -1);

        private int tracking = -1;
        private int highlight = -1;

        //备注：设置三角形尺寸
        private const int triangleSize = 7;
        private /*const*/ int triangleHalfLength = (triangleSize - 1) / 2;

        private AnchorStyles alignmentStyle = AnchorStyles.Left;

        public AnchorStyles AlignmentStyle
        {
            get
            {
                return this.alignmentStyle;
            }

            set
            {
                if (value != this.alignmentStyle)
                {
                    this.alignmentStyle = value;
                    Invalidate();
                }
            }
        }

        protected override void OnMouseLeave(EventArgs e)
        {
            base.OnMouseLeave(e);
            //int oldhighlight = highlight;
            highlight = -1;
            //this.InvalidateTriangle(oldhighlight);
            this.Refresh();
        }
        protected override void OnMouseMove(MouseEventArgs e)
        {
            base.OnMouseMove(e);
            highlight = 1;
            this.Refresh();
        }

        protected override void OnMouseDown(MouseEventArgs e)
        {
            base.OnMouseDown(e);

            if (e.Button == MouseButtons.Left)
            {
                tracking = 1;
                this.Refresh();
            }
        }

        protected override void OnMouseUp(MouseEventArgs e)
        {
            base.OnMouseUp(e);

            if (e.Button == MouseButtons.Left)
            {
                tracking = -1;
            }
            this.Refresh();
        }

        private void DrawGradient(Graphics g)
        {
            g.PixelOffsetMode = PixelOffsetMode.Half;

            // draw value triangles

            int pos = 0;// triangleHalfLength + 0;
            Brush brush;
            Pen pen;

            if (-1 != tracking)
            {
                brush = Brushes.Blue;// Blue;
                pen = (Pen)Pens.Transparent/*White*/.Clone();
            }
            else if(-1 != highlight)
            {
                brush = Brushes.LightGray;// Black;
                pen = (Pen)Pens.Blue.Clone();
            }
            else
            {
                brush = Brushes.LightGray;// Black;
                pen = (Pen)Pens.Gray.Clone();
            }


            g.SmoothingMode = SmoothingMode.AntiAlias;
            triangleHalfLength = (int)((Height - 1) / 2);
            Point a1 = new Point(0, 0);// new Point(pos - triangleHalfLength, 0);
            Point b1 = new Point(0, Height - 1);//new Point(pos, triangleSize - 1);
            Point c1 = new Point(Width - 1, pos + triangleHalfLength);//new Point(pos + triangleHalfLength, 0);

            switch (this.alignmentStyle)
            {
                case AnchorStyles.Left:
                    //    gradientAngle = 180.0f;
                    break;

                case AnchorStyles.Right:
                    a1 = new Point(Width - 1, 0);// new Point(pos - triangleHalfLength, 0);
                    b1 = new Point(Width - 1, Height - 1);//new Point(pos, triangleSize - 1);
                    c1 = new Point(0, pos + triangleHalfLength);//new Point(pos + triangleHalfLength, 0);
                    break;

                default:
                    throw new InvalidEnumArgumentException();
            }

                    //Point a2 = new Point(a1.X, Height - 1 - a1.Y);
                    //Point b2 = new Point(b1.X, Height - 1 - b1.Y);
                    //Point c2 = new Point(c1.X, Height - 1 - c1.Y);

                    //if (this.drawNearNub)
                    //{//倒三角
                    g.FillPolygon(brush, new Point[] { a1, b1, c1, a1 });
            //}

            ////if (this.drawFarNub)
            ////{//正三角
            //    g.FillPolygon(brush, new Point[] { a2, b2, c2, a2 });
            ////}

            //if (pen != null)
            //{
            //    if (this.drawNearNub)
            //    {
                    g.DrawPolygon(pen, new Point[] { a1, b1, c1, a1 });
                //}

                ////if (this.drawFarNub)
                ////{
                //    g.DrawPolygon(pen, new Point[] { a2, b2, c2, a2 });
                ////}

                pen.Dispose();
            //}
        }

        protected override void OnPaint(PaintEventArgs e)
        {
            base.OnPaint(e);
            DrawGradient(e.Graphics);
        }

        protected override void OnPaintBackground(PaintEventArgs pevent)
        {
            base.OnPaintBackground(pevent);
            DrawGradient(pevent.Graphics);
        }




    }
}