using System;
using System.Collections.Generic;
using System.Drawing;
using System.Drawing.Drawing2D;
using System.Drawing.Imaging;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace GummingCommon
{
    public class KChart
    {
        private int _width;
        private int _height;
        private int _marginleft;
        private int _margintop;
        private int _chartwidth;
        private int _chartheight;
        private float _ymaxvalue;
        private int _bottomline;
        private int _centerline;
        private bool _iscenterline;
        private float _ystep;
        private float _xstep;
        private float _xelementsize;
        private Font font = new Font("Airal", 10);
        private SolidBrush brush = new SolidBrush(Color.Black);
        private Bitmap _expbmp;

        public KChart(int width, int height, int marginleft, int margintop, int marginbottom, int marginright)
        {
            _width = width;
            _height = height;
            _marginleft = marginleft;
            _margintop = margintop;
            _chartwidth = width - marginleft - marginright;
            _chartheight = height -margintop - marginbottom;
            _bottomline = height - marginbottom;
            _centerline = _chartheight / 2 + margintop;

            _expbmp = new Bitmap(_width, _height, PixelFormat.Format24bppRgb);
            _expbmp.SetResolution(96, 96);
        }

        public Bitmap Publish()
        {
            return _expbmp;
        }

        public void CreateBaseCoordinate(bool iscenter)
        {
            _iscenterline = iscenter;
            Graphics g = Graphics.FromImage(_expbmp);
            g.Clear(Color.White);
            g.DrawLine(Pens.Black, new Point(_marginleft, _bottomline), new Point(_marginleft, _margintop));
            if (iscenter)
            {
                g.DrawLine(Pens.Black, new Point(_marginleft, _centerline), new Point(_marginleft + _chartwidth, _centerline));
                g.DrawString("0", font, brush, _marginleft - 5, _centerline - 7, new StringFormat() { Alignment = StringAlignment.Far });
            }
            else
            {
                g.DrawLine(Pens.Black, new Point(_marginleft, _bottomline), new Point(_marginleft + _chartwidth, _bottomline));
                g.DrawString("0", font, brush, _marginleft - 5, _bottomline - 7, new StringFormat() { Alignment = StringAlignment.Far });
            }            

            g.Flush();
            g.Dispose();
        }

        public void CreateVCoordinateLine(string title, float ymaxvalue, int count, bool showradix)
        {
            _ymaxvalue = ymaxvalue;
            Graphics g = Graphics.FromImage(_expbmp);

            _ystep = (int)Math.Floor(_chartheight * 1.0 / count);
            decimal displaystep;
            if (_ymaxvalue > 1 && !showradix)
            {
                displaystep = (decimal)Math.Floor(_ymaxvalue * 1.0 / count);
            }
            else
            {
                displaystep = (decimal)Math.Round(_ymaxvalue * 1.0 / count, 2);
            }

            SizeF wordsize = g.MeasureString("温", font);
            int start = (int)((_chartheight - wordsize.Height* title.Length) / 2);

            for (int i = 0; i < title.Length; i++)
            {
                g.DrawString(title.Substring(i, 1), font, brush, 10, start + wordsize.Height * i + 2, new StringFormat() { Alignment = StringAlignment.Center });
            }
            if (_iscenterline)
            {
                for (int i = 1; i < (count + 1) /2; i++)
                {
                    g.DrawLine(Pens.LightGray, new Point(_marginleft + 1, (int)(_centerline - _ystep * i)), new Point(_marginleft + _chartwidth, (int)(_centerline - _ystep * i)));
                    g.DrawString(((decimal)(displaystep * i)).ToString(), font, brush, _marginleft - 5, _centerline - _ystep * i - 8, new StringFormat() { Alignment = StringAlignment.Far });

                    g.DrawLine(Pens.LightGray, new Point(_marginleft + 1, (int)(_centerline + _ystep * i)), new Point(_marginleft + _chartwidth, (int)(_centerline + _ystep * i)));
                    g.DrawString(((decimal)(displaystep * i *-1)).ToString(), font, brush, _marginleft - 5, _centerline + _ystep * i - 8, new StringFormat() { Alignment = StringAlignment.Far });
                }                
            }
            else
            {   
                for (int i = 1; i < count + 1; i++)
                {
                    g.DrawLine(Pens.LightGray, new Point(_marginleft + 1, (int)(_bottomline - _ystep * i)), new Point(_marginleft + _chartwidth, (int)(_bottomline - _ystep * i)));

                    g.DrawString(((decimal)(displaystep * i)).ToString(), font, brush, _marginleft - 5, _bottomline - _ystep * i - 8, new StringFormat() { Alignment = StringAlignment.Far });
                }
            }
            g.Flush();
            g.Dispose();
        }

        public void CreateHCoordinateLine(List<string> titles, bool withline)
        {                
            Graphics g = Graphics.FromImage(_expbmp);           
            int count = titles.Count + 1;
            int step = (int)(_chartwidth / (count));

            int currentline = _bottomline;
            if (_iscenterline)
            {
                currentline = _centerline;
            }

            for (int i = 1; i < count; i++)
            {
                if (withline)
                {
                    g.DrawLine(Pens.LightGray, new Point(_marginleft + step * i, currentline), new Point(_marginleft + step * i, currentline - 5));
                }
                //g.DrawString(titles[i - 1], font, brush, _marginleft + step * i, currentline + 3, new StringFormat() { Alignment = StringAlignment.Center });

                if (count > 40)
                {
                    if (i % 2 == 0)
                    {
                        g.DrawString(titles[i - 1], font, brush, _marginleft + step * i, currentline + 18, System.Drawing.StringFormat.GenericTypographic);
                    }
                    else
                    {
                        g.DrawString(titles[i - 1], font, brush, _marginleft + step * i, currentline + 3, System.Drawing.StringFormat.GenericTypographic);
                    }
                }
                else
                {
                    DrawString(g, titles[i - 1], font, brush, new PointF(_marginleft + step * i, currentline + 3), new StringFormat() { Alignment = StringAlignment.Center }, -45);
                }
            }

            g.Flush();
            g.Dispose();
        }

        public void DrawText(string title, PointF p)
        {
            Graphics g = Graphics.FromImage(_expbmp);
            DrawString(g, title, font, brush, p, new StringFormat() { Alignment = StringAlignment.Center }, 0);
        }

        public void DrawString(Graphics g, string s, Font font, Brush brush, PointF point, StringFormat format, float angle)
        {
            // Save the matrix  
            Matrix mtxSave = g.Transform;

            Matrix mtxRotate = g.Transform;
            mtxRotate.RotateAt(angle, point);
            g.Transform = mtxRotate;

            g.DrawString(s, font, brush, point, format);

            // Reset the matrix  
            g.Transform = mtxSave;
        }

        public void CreateBarChart(List<float> points, int size, Color color)
        {
            _xelementsize = size;
            Graphics g = Graphics.FromImage(_expbmp);
            int count = points.Count + 1;
            int step = (int)(_chartwidth / (count));

            int charth = _chartheight;
            if (_iscenterline)
            {
                charth = _chartheight / 2;
            }
            for (int i = 1; i < count; i++)
            {
                int barheight = (int)(points[i - 1] * _chartheight / _ymaxvalue);
                if (barheight < 0)
                {
                    g.FillRectangle(new SolidBrush(color), new Rectangle(_marginleft + step * i - size / 2, _centerline, size, Math.Abs(barheight)));
                }
                else
                {
                    g.FillRectangle(new SolidBrush(color), new Rectangle(_marginleft + step * i - size / 2, _margintop + (charth - barheight), size, barheight));
                }
            }

            g.Flush();
            g.Dispose();
        }

        public void CreateLineChart(List<float> points, int size, Color color)
        {
            _xelementsize = size;
            Graphics g = Graphics.FromImage(_expbmp);
            int count = points.Count + 1;
            int step = (int)(_chartwidth / (count));

            int charth = _chartheight;
            if (_iscenterline)
            {
                charth = _chartheight / 2;
            }
            for (int i = 1; i < count ; i++)
            {
                int previousP = (int)(points[i - 1] * _chartheight / _ymaxvalue);                
                g.FillEllipse(new SolidBrush(Color.FromArgb(30, 30, 255)), new Rectangle(_marginleft + step * i - 2, _margintop + (charth - previousP) - 2, 4, 4));

                if (i < count - 1)
                {
                    int currentP = (int)(points[i] * _chartheight / _ymaxvalue);
                    g.DrawLine(new Pen(color), new Point(_marginleft + step * i, _margintop + (charth - previousP)),
                        new Point(_marginleft + step * (i + 1), _margintop + (charth - currentP)));
                }
            }

            g.Flush();
            g.Dispose();
        }
    }
}