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

namespace Customize.Controls
{
    public partial class ImageMask
    : System.Windows.Forms.Control
    {
        public string fileName;

        public ImageMask()
        {
            this.SetStyle(ControlStyles.SupportsTransparentBackColor, true);
            //this.BackColor = Color.Empty;
            this.BackColor = Color.Transparent;
            //this.BackColor = Color.FromArgb(50, Color.Red);

            //以下是设置双缓冲的代码 要不然在下面onPaint里的绘制半透明背景会让你很伤心，或者上面那句设置半透明背景用了过后拖动时也会让你跟蜗牛一样。
            this.SetStyle(ControlStyles.UserPaint, true);
            this.SetStyle(ControlStyles.AllPaintingInWmPaint, true); // 禁止擦除背景.
            this.SetStyle(ControlStyles.DoubleBuffer, true);
        }

        public Size border;

        //public void showBorder() { }

        private Point m_MousePoint;
        private Size m_Size;
        private Point m_LastPoint;


        protected override void OnMouseDown(MouseEventArgs e)
        {
            base.OnMouseDown(e);
            this.m_LastPoint = this.Location;
            this.m_MousePoint = this.PointToScreen(e.Location);
            this.m_Size = this.Size;
            //this.BackColor = Color.Empty;
        }


        protected override void OnMouseMove(MouseEventArgs e)
        {

            base.OnMouseMove(e);

            if (arow != arrowType.none)
            {
                reSize(e);
                return;
            }

            if (e.Y <= recArrow[4].Bottom && e.Y >= recArrow[4].Top && e.X >= recArrow[4].Left && e.X <= recArrow[4].Right)//左上
                Cursor = Cursors.SizeNWSE;
            else if (e.Y <= recArrow[5].Bottom && e.Y >= recArrow[5].Top && e.X >= recArrow[5].Left && e.X <= recArrow[5].Right)//左下
                Cursor = Cursors.SizeNESW;
            else if (e.Y <= recArrow[6].Bottom && e.Y >= recArrow[6].Top && e.X >= recArrow[6].Left && e.X <= recArrow[6].Right)//右上
                Cursor = Cursors.SizeNESW;
            else if (e.Y <= recArrow[7].Bottom && e.Y >= recArrow[7].Top && e.X >= recArrow[7].Left && e.X <= recArrow[7].Right)//右下
                Cursor = Cursors.SizeNWSE;
            else if (e.Y <= recArrow[0].Bottom && e.Y >= recArrow[0].Top)//上
                Cursor = Cursors.SizeNS;
            else if (e.Y <= recArrow[1].Bottom && e.Y >= recArrow[1].Top)//下
                Cursor = Cursors.SizeNS;
            else if (e.X >= recArrow[2].Left && e.X <= recArrow[2].Right)//左
                Cursor = Cursors.SizeWE;
            else if (e.X >= recArrow[3].Left && e.X <= recArrow[3].Right)//右
                Cursor = Cursors.SizeWE;
            else
                Cursor = Cursors.SizeAll;


            if (e.Button == MouseButtons.Left)
            {
                Point t = this.PointToScreen(e.Location);
                Point l = this.m_LastPoint;

                if (e.Y <= recArrow[4].Bottom && e.Y >= recArrow[4].Top && e.X >= recArrow[4].Left && e.X <= recArrow[4].Right)//左上
                    arow = arrowType.leftUp;
                else if (e.Y <= recArrow[5].Bottom && e.Y >= recArrow[5].Top && e.X >= recArrow[5].Left && e.X <= recArrow[5].Right)//左下
                    arow = arrowType.leftDown;
                else if (e.Y <= recArrow[6].Bottom && e.Y >= recArrow[6].Top && e.X >= recArrow[6].Left && e.X <= recArrow[6].Right)//右上
                    arow = arrowType.rightUp;
                else if (e.Y <= recArrow[7].Bottom && e.Y >= recArrow[7].Top && e.X >= recArrow[7].Left && e.X <= recArrow[7].Right)//右下
                    arow = arrowType.rightDown;
                else if (e.Y <= recArrow[0].Bottom && e.Y >= recArrow[0].Top)//上
                    arow = arrowType.up;
                else if (e.Y <= recArrow[1].Bottom && e.Y >= recArrow[1].Top)//下
                    arow = arrowType.down;
                else if (e.X >= recArrow[2].Left && e.X <= recArrow[2].Right)//左
                    arow = arrowType.left;
                else if (e.X >= recArrow[3].Left && e.X <= recArrow[3].Right)//右
                    arow = arrowType.right;
                else
                    arow = arrowType.none;


                l.Offset(t.X - this.m_MousePoint.X, t.Y - this.m_MousePoint.Y);
                if (arow != arrowType.none)
                    reSize(e);
                else
                {
                    this.Location = l;
                    Refresh();//这句很重要立即重绘 不然拖动到时候会出现卡卡 的现象 ，找了半天原因
                }
            }
        }

        public void reSize(MouseEventArgs e)
        {
            Point t = this.PointToScreen(e.Location);
            Point l = this.m_LastPoint;

            l.Offset(t.X - this.m_MousePoint.X, t.Y - this.m_MousePoint.Y);

            switch (arow)
            {
                case arrowType.up:
                    {
                        this.Height = m_Size.Height - (t.Y - this.m_MousePoint.Y);
                        this.Location = new Point(m_LastPoint.X, l.Y);
                        break;
                    }
                case arrowType.down:
                    {
                        this.Height = m_Size.Height + (t.Y - this.m_MousePoint.Y);
                        break;
                    }
                case arrowType.left:
                    {
                        this.Width = m_Size.Width - (t.X - this.m_MousePoint.X);
                        this.Location = new Point(l.X, m_LastPoint.Y);
                        break;
                    }
                case arrowType.right:
                    {
                        this.Width = m_Size.Width + (t.X - this.m_MousePoint.X);
                        break;
                    }
                case arrowType.leftUp:
                    {
                        this.Width = m_Size.Width - (t.X - this.m_MousePoint.X);
                        this.Height = m_Size.Height - (t.Y - this.m_MousePoint.Y);
                        this.Location = new Point(l.X, l.Y);
                        break;
                    }
                case arrowType.leftDown:
                    {
                        this.Width = m_Size.Width - (t.X - this.m_MousePoint.X);
                        this.Height = m_Size.Height + (t.Y - this.m_MousePoint.Y);
                        this.Location = new Point(l.X, m_LastPoint.Y);
                        break;
                    }
                case arrowType.rightUp:
                    {
                        this.Width = m_Size.Width + (t.X - this.m_MousePoint.X);
                        this.Height = m_Size.Height - (t.Y - this.m_MousePoint.Y);
                        this.Location = new Point(m_LastPoint.X, l.Y);
                        break;
                    }
                case arrowType.rightDown:
                    {
                        this.Width = m_Size.Width + (t.X - this.m_MousePoint.X);
                        this.Height = m_Size.Height + (t.Y - this.m_MousePoint.Y);
                        break;
                    }
            }
            this.Refresh();
        }



        public enum arrowType
        {
            up, down, left, right, leftUp, leftDown, rightUp, rightDown, none
        }

        public arrowType arow = arrowType.none;

        Rectangle[] recArrow = new Rectangle[8];//8个手柄

        public Rectangle area;//选择区域
        public readonly int blank = 8;//边距
        protected override void OnPaint(PaintEventArgs e)
        {
            int side = 6;//手柄矩形的边长

            recArrow[0] = new Rectangle(new Point(this.Width / 2 - side / 2, blank - side / 2), new Size(side, side));
            recArrow[1] = new Rectangle(new Point(this.Width / 2 - side / 2, this.Height - blank - side / 2), new Size(side, side));
            recArrow[2] = new Rectangle(new Point(blank - side / 2, this.Height / 2 - side / 2), new Size(side, side));
            recArrow[3] = new Rectangle(new Point(this.Width - blank - side / 2, this.Height / 2 - side / 2), new Size(side, side));
            recArrow[4] = new Rectangle(new Point(blank - side / 2, blank - side / 2), new Size(side, side));
            recArrow[5] = new Rectangle(new Point(blank - side / 2, this.Height - blank - side / 2), new Size(side, side));
            recArrow[6] = new Rectangle(new Point(this.Width - blank - side / 2, blank - side / 2), new Size(side, side));
            recArrow[7] = new Rectangle(new Point(this.Width - blank - side / 2, this.Height - blank - side / 2), new Size(side, side));

            foreach (Rectangle item in recArrow)
                e.Graphics.DrawRectangle(Pens.Red, item);
            area = new Rectangle(new Point(8, 8), new Size(this.Width - 8 * 2, this.Height - 8 * 2));

            ////加上半透明效果看倒是好看了 重绘的时候卡的凶 ，期待有解决方法
            e.Graphics.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.AntiAlias;
            System.Drawing.Color cor = System.Drawing.Color.FromArgb(50, Color.Red);
            System.Drawing.SolidBrush bsh = new System.Drawing.SolidBrush(cor);
            e.Graphics.FillRectangle(bsh, area);

            e.Graphics.DrawRectangle(Pens.Red, area);
        }

        protected override void OnMouseUp(MouseEventArgs e)
        {
            arow = arrowType.none;
            //this.BackColor = Color.FromArgb(0, Color.Red);
        }

    }
}