using System;
using System.Collections.Generic;
using System.Drawing;
using System.Drawing.Drawing2D;
using System.Windows.Forms;
using System.Linq;
namespace HySoft.FlowEditor
{
    public partial class FlowBrokenLineControl : UserControl
    {
        #region 字段
        /// <summary>
        /// 线宽
        /// </summary>
        int _lineWidth = 2;
        /// <summary>
        /// 线半宽
        /// </summary>
        int _lineHalfWidth = 1;
        /// <summary>
        /// 图形路径
        /// </summary>
        GraphicsPath _graphicsPath;
        /// <summary>
        /// 折线点
        /// </summary>
        List<Point> _points;
        /// <summary>
        /// 线颜色
        /// </summary>
        Color _lineColor;
        /// <summary>
        /// 被选中时的线颜色
        /// </summary>
        Color _selectedLineColor;
        /// <summary>
        /// 是否有箭头
        /// </summary>
        bool _bArrow = true;
        /// <summary>
        /// 绑定的线对象
        /// </summary>
        FlowLine _flowLine;
        /// <summary>
        /// 是否被选中
        /// </summary>
        bool _bSelected;
        #endregion

        #region 属性
        /// <summary>
        /// 折线组成的点的列表
        /// </summary>
        public List<Point> PointList
        {
            get { return _points; }
            set 
            {
                _points = value;
                SetControlRegion();
            }
        }
        /// <summary>
        /// 线颜色
        /// </summary>
        public Color LineColor
        {
            get { return _lineColor; }
            set 
            { 
                _lineColor = value;
                if (!_bSelected)
                    BackColor = _lineColor;
            }
        }
        /// <summary>
        /// 被选中时的线颜色
        /// </summary>
        public Color SelectedLineColor
        {
            get { return _selectedLineColor; }
            set
            {
                _selectedLineColor = value;
                if (_bSelected)
                    BackColor = _lineColor;
            }
        }
        /// <summary>
        /// 是否被选中
        /// </summary>
        public bool BeSelected
        {
            get { return _bSelected; }
            set
            {
                if (_bSelected != value)
                {
                    _bSelected = value;
                    if (_bSelected)
                        BackColor = _selectedLineColor;
                    else
                        BackColor = _lineColor;
                }
            }
        }
        /// <summary>
        /// 线宽
        /// </summary>
        public int LineWidth
        {
            get { return _lineWidth; }
            set 
            { 
                if(value < 2)
                    _lineWidth = 2;
                else
                    _lineWidth = value;
                _lineHalfWidth = (_lineWidth + 1) / 2;
                SetControlRegion();
            }
        }
        /// <summary>
        /// 绑定的线对象
        /// </summary>
        public FlowLine FlowLine
        {
            get { return _flowLine; }
            set { _flowLine = value; }
        }

        #endregion

        #region 公开方法
        /// <summary>
        /// 构造方法
        /// </summary>
        public FlowBrokenLineControl()
        {
            InitializeComponent();  
         
            this.BackColor = _lineColor;
            this.BorderStyle = System.Windows.Forms.BorderStyle.None;

            this.ResumeLayout(false);
        }

        /// <summary>
        /// 构造方法
        /// </summary>
        /// <param name="line">绑定的线</param>
        public FlowBrokenLineControl(FlowLine line)
        {
            InitializeComponent();

            _flowLine = line;
            this.BackColor = _lineColor;
            this.BorderStyle = System.Windows.Forms.BorderStyle.None;

            this.ResumeLayout(false);
        }


        #endregion

        #region 私有方法
        /// <summary>
        /// 重新设置控件的GraphicsPath
        /// </summary>
        void ResetControlGraphicsPath()
        {
            _graphicsPath = GetGraphicsPath();
        }
        /// <summary>
        /// (废弃的)获取GraphicsPath
        /// </summary>
        /// <returns></returns>
        GraphicsPath OldGetGraphicsPath()
        {
            ///计算points
            if (_points == null || _points.Count < 2)
                return null;
            Point[] points = new Point[_points.Count * 2];
            //计算第一个点
            TwoPointPos begainTwoPointPos = GetTwoPointPos(_points[0], _points[1]);
            switch (begainTwoPointPos)
            {
                case TwoPointPos.Down:
                case TwoPointPos.Up:
                    points[0] = new Point(_points[0].X - _lineHalfWidth, _points[0].Y);
                    points[_points.Count * 2 - 1] = new Point(_points[0].X + _lineHalfWidth, _points[0].Y);
                    break;
                case TwoPointPos.Left:
                case TwoPointPos.Right:
                    points[0] = new Point(_points[0].X, _points[0].Y - _lineHalfWidth);
                    points[_points.Count * 2 - 1] = new Point(_points[0].X, _points[0].Y + _lineHalfWidth);
                    break;
            }

            //计算中间点
            int i = 0;
            for (; i < _points.Count - 2; i++)
            {
                ThreePointPos threePointPos = GetThreePointPos(_points[i], _points[i + 1], _points[i + 2]);
                switch (threePointPos)
                {
                    case ThreePointPos.Down:
                    case ThreePointPos.Up:
                        points[i + 1] = new Point(_points[i + 1].X - _lineHalfWidth, _points[i + 1].Y);
                        points[points.Length - i - 2] = new Point(_points[i + 1].X + _lineHalfWidth, _points[i + 1].Y);
                        break;
                    case ThreePointPos.Left:
                    case ThreePointPos.Right:
                        points[i + 1] = new Point(_points[i + 1].X, _points[i + 1].Y - _lineHalfWidth);
                        points[points.Length - i - 2] = new Point(_points[i + 1].X, _points[i + 1].Y + _lineHalfWidth);
                        break;
                    case ThreePointPos.UpRight:
                    case ThreePointPos.DownLeft:
                    case ThreePointPos.RightUp:
                    case ThreePointPos.LeftDown:
                        points[i + 1] = new Point(_points[i + 1].X - _lineHalfWidth, _points[i + 1].Y - _lineHalfWidth);
                        points[points.Length - i - 2] = new Point(_points[i + 1].X + _lineHalfWidth, _points[i + 1].Y + _lineHalfWidth);
                        break;
                    case ThreePointPos.UpLeft:
                    case ThreePointPos.DownRight:
                    case ThreePointPos.LeftUp:
                    case ThreePointPos.RightDown:
                        points[i + 1] = new Point(_points[i + 1].X - _lineHalfWidth, _points[i + 1].Y + _lineHalfWidth);
                        points[points.Length - i - 2] = new Point(_points[i + 1].X + _lineHalfWidth, _points[i + 1].Y - _lineHalfWidth);
                        break;
                }
            }
            //计算最后一个点
            TwoPointPos endTwoPointPos = GetTwoPointPos(_points[_points.Count - 2], _points[_points.Count - 1]);
            switch (endTwoPointPos)
            {
                case TwoPointPos.Down:
                case TwoPointPos.Up:
                    points[i + 1] = new Point(_points[i + 1].X - _lineHalfWidth, _points[i + 1].Y);
                    points[points.Length - i - 2] = new Point(_points[i + 1].X + _lineHalfWidth, _points[i + 1].Y);
                    break;
                case TwoPointPos.Left:
                case TwoPointPos.Right:
                    points[i + 1] = new Point(_points[i + 1].X, _points[i + 1].Y - _lineHalfWidth);
                    points[points.Length - i - 2] = new Point(_points[i + 1].X, _points[i + 1].Y + _lineHalfWidth);
                    break;
            }

            //计算types
            if (points == null && points.Length <= 2)
                return null;
            Byte[] types = new Byte[points.Length];
            for (int j = 0; j < types.Length; j++)
            {
                types[j] = (Byte)PathPointType.Line;
            }

            System.Drawing.Drawing2D.GraphicsPath path = new GraphicsPath(points, types); 
            return path;
        }
        /// <summary>
        /// 获取GraphicsPath
        /// </summary>
        /// <returns></returns>
        GraphicsPath GetGraphicsPath()
        {
            ///计算points
            if (_points == null || _points.Count < 2)
                return null;
            Rectangle[] rects = new Rectangle[_points.Count - 1];

            for (int i = 0; i < _points.Count - 1; i++)
            {
                rects[i] = new Rectangle();
                TwoPointPos twoPointPos = GetTwoPointPos(_points[i], _points[i+1]);
                switch (twoPointPos)
                {
                    case TwoPointPos.Up:
                        rects[i] = new Rectangle(_points[i + 1].X - _lineHalfWidth, _points[i + 1].Y, _lineHalfWidth * 2, _points[i].Y - _points[i + 1].Y);
                        break;
                    case TwoPointPos.Down:
                        rects[i] = new Rectangle(_points[i].X - _lineHalfWidth, _points[i].Y, _lineHalfWidth * 2, _points[i + 1].Y - _points[i].Y);
                        break;
                    case TwoPointPos.Left:
                        rects[i] = new Rectangle(_points[i + 1].X, _points[i + 1].Y - _lineHalfWidth, _points[i].X - _points[i + 1].X, _lineHalfWidth * 2);
                        break;
                    case TwoPointPos.Right:
                        rects[i] = new Rectangle(_points[i].X, _points[i + 1].Y - _lineHalfWidth, _points[i + 1].X - _points[i].X, _lineHalfWidth * 2);
                        break;
                }
            }

            System.Drawing.Drawing2D.GraphicsPath path = new GraphicsPath();

            //添加箭头
            if (_bArrow)
            {
                Point headPoint = _points[_points.Count - 1];
                Point tailPoint = _points[_points.Count - 2];
                Point pos2 = new Point();
                Point pos3 = new Point();

                TwoPointPos twoPointPos = GetTwoPointPos(tailPoint, headPoint);
                switch (twoPointPos)
                {
                    case TwoPointPos.Up:
                        pos2.X = headPoint.X - (_lineWidth * 2);
                        pos2.Y = headPoint.Y + (_lineWidth * 2);
                        pos3.X = headPoint.X + (_lineWidth * 2);
                        pos3.Y = pos2.Y; 
                        break;
                    case TwoPointPos.Down:
                        pos2.X = headPoint.X - (_lineWidth * 2);
                        pos2.Y = headPoint.Y - (_lineWidth * 2);
                        pos3.X = headPoint.X + (_lineWidth * 2);
                        pos3.Y = pos2.Y;
                        break;
                    case TwoPointPos.Left:
                        pos2.X = headPoint.X + (_lineWidth * 2);
                        pos2.Y = headPoint.Y - (_lineWidth * 2);
                        pos3.X = pos2.X;
                        pos3.Y = headPoint.Y + (_lineWidth * 2);
                        break;
                    case TwoPointPos.Right:
                        pos2.X = headPoint.X - (_lineWidth * 2);
                        pos2.Y = headPoint.Y - (_lineWidth * 2);
                        pos3.X = pos2.X;
                        pos3.Y = headPoint.Y + (_lineWidth * 2);
                        break;
                }
                Point[] arrowPoints = new Point[] { headPoint, pos2, pos3 };
                path.AddPolygon(arrowPoints);
            }

            path.AddRectangles(rects.ToArray());
            return path;
        }
        /// <summary>
        /// 设置控件的区域
        /// </summary>
        void SetControlRegion()
        {
            ResetControlGraphicsPath();
            if(_graphicsPath != null)
                this.Region = new Region(_graphicsPath);
        }

        /// <summary>
        /// 判断2个点的位置，第二个相对于第一个点的位置
        /// 
        /// </summary>
        /// <param name="point1"></param>
        /// <param name="point2"></param>
        /// <returns></returns>
        public static TwoPointPos GetTwoPointPos(Point point1, Point point2)
        {
            if (point2.X > point1.X)
            {
                return TwoPointPos.Right;
            }
            else if (point2.X < point1.X)
            {
                return TwoPointPos.Left;
            }
            else
            {
                if (point2.Y > point1.Y)
                    return TwoPointPos.Down;
                else
                    return TwoPointPos.Up;
            }
        }
        /// <summary>
        /// 判断三个点的位置
        /// </summary>
        /// <param name="point1"></param>
        /// <param name="point2"></param>
        /// <param name="point3"></param>
        /// <returns></returns>
        ThreePointPos GetThreePointPos(Point point1, Point point2, Point point3)
        {
            TwoPointPos point2Pos = GetTwoPointPos(point1, point2);
            TwoPointPos point3Pos = GetTwoPointPos(point2, point3);
            if (point2Pos == TwoPointPos.Right)
            {
                if (point3Pos == TwoPointPos.Right)
                    return ThreePointPos.Right;
                else if (point3Pos == TwoPointPos.Up)
                    return ThreePointPos.RightUp;
                else if (point3Pos == TwoPointPos.Down)
                    return ThreePointPos.RightDown;
            }
            else if (point2Pos == TwoPointPos.Left)
            {
                if (point3Pos == TwoPointPos.Left)
                    return ThreePointPos.Left;
                else if (point3Pos == TwoPointPos.Up)
                    return ThreePointPos.LeftUp;
                else if (point3Pos == TwoPointPos.Down)
                    return ThreePointPos.LeftDown;
            }
            else if (point2Pos == TwoPointPos.Up)
            {
                if (point3Pos == TwoPointPos.Up)
                    return ThreePointPos.Up;
                else if (point3Pos == TwoPointPos.Right)
                    return ThreePointPos.UpRight;
                else if (point3Pos == TwoPointPos.Left)
                    return ThreePointPos.UpLeft;
            }
            //Down
            if (point3Pos == TwoPointPos.Down)
                return ThreePointPos.Down;
            else if (point3Pos == TwoPointPos.Right)
                return ThreePointPos.DownRight;
            //Left
            return ThreePointPos.DownLeft;
        }
        #endregion

        #region 控件响应方法
        #endregion
    }
    /// <summary>
    /// 两个点相对位置类型
    /// </summary>
    public enum TwoPointPos
    {
        Left,
        Up,
        Right,
        Down,
    }
    /// <summary>
    /// 三个点相对位置类型
    /// </summary>
    public enum ThreePointPos
    {
        LeftUp,
        RightUp,
        RightDown,
        LeftDown,
        UpRight,
        UpLeft,
        DownLeft,
        DownRight,
        Left,
        Right,
        Up,
        Down,
    }
}