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

namespace Unplugged.Segy
{
    public class GraphicsWriter
    {
        private float _TraceWidth = 10;
        private Pen _DrawPen = Pens.Black;
        public Pen DrawPen { get=>_DrawPen; set=>_DrawPen=value; }
        public float TraceWidth { get => _TraceWidth; set => _TraceWidth=value; }
        public Brush DrawBrush { get => drawBrush; set => drawBrush=value; }
        private int wholeWidth;
        private int wholeHeight;

        private int SampleInteral;
        private int SampleNumber;
        private Brush drawBrush = Brushes.Black;
        private static ValueRange FindRange(IEnumerable<ITrace> traces)
        {
            var min = float.MaxValue;
            var max = float.MinValue;
            foreach (var trace in traces)
                foreach (var value in trace.Values)
                {
                    if (float.IsInfinity(value)) continue;
                    if (value<min) min=value;
                    if (value>max) max=value;
                }
            return new ValueRange { Min=min, Max=max, Delta=max-min };
        }
        public Image WriteImg(int width, ISegyFile segyFile)
        {
            int nBorderLeft = 100;
            wholeWidth=width+nBorderLeft;
            //float fZoom = 1.0f;
            //fZoom=Math.Min(width/symbol.Width, height/symbol.Height);
            
            SampleNumber=segyFile.Header.SampleNumber;
            SampleInteral=segyFile.Header.SampleInteral;
            int nTraceCount = segyFile.Traces.Count();
            if (nTraceCount<=0) { return null; }
            //wholeHeight = segyFile.Traces[0].Values.Count;
            wholeHeight=(int)TransDongying(SampleNumber);

            TraceWidth=(float)wholeWidth/(float)nTraceCount;
            Color bkColor = Color.Transparent;
            //int fClientWidth = width, fClientHeight = 0;
            Bitmap dst = new Bitmap(wholeWidth, wholeHeight);//, PixelFormat.DontCare);
            Graphics g = Graphics.FromImage(dst);
            // 设置高质量插值法
            g.InterpolationMode=System.Drawing.Drawing2D.InterpolationMode.Default;
            //设置高质量,低速度呈现平滑程度   
            g.SmoothingMode=System.Drawing.Drawing2D.SmoothingMode.Default;
            g.CompositingQuality=System.Drawing.Drawing2D.CompositingQuality.Default;
            // 消除锯齿
            g.SmoothingMode=SmoothingMode.Default;
            g.Clear(bkColor);

            //Matrix mx = new Matrix();
            //mx.Translate(-fClientWidth/2f, -fClientHeight/2f, MatrixOrder.Append);
            //mx.Rotate(rotation, MatrixOrder.Append);
            //mx.Translate(fClientWidth/2f, fClientHeight/2f, MatrixOrder.Append);
            //mx.Scale(fZoom, fZoom, MatrixOrder.Append);
            //g.Transform=mx;

            //SolidBrush brush = new SolidBrush(Color.FromArgb(255, 255, 255));
            //g.FillRectangle(brush, ClientRectangle);
            g.TranslateTransform(nBorderLeft, 0);
            Draw(g, segyFile);            
            // 绘制边框
            g.DrawLine(DrawPen, 0, 0, 0, wholeHeight);

            int nScaleHStep = 20;
            //float fScaleHSpace = TraceWidth*nScaleHStep;
            Font ftScaleH = new Font("宋体", 20);
            for (int i = 0; i<nTraceCount; i+=nScaleHStep)
            {
                float fX = TraceWidth* i;
                float fY = 0;
                g.DrawString(i+"", ftScaleH, Brushes.Black, fX, fY);
            }

            g.ResetTransform();
            // 画刻度
            int nScaleVSpace = 250;
            int nScaleVCount = wholeHeight/nScaleVSpace;
            int nScaleV = 0;
            Font ftScale = new Font("宋体", 25);
            for (int i=0;i<=nScaleVCount;i++)
            {                
                g.DrawLine(DrawPen, nBorderLeft-25, nScaleV, nBorderLeft, nScaleV);

                SizeF sizeF = g.MeasureString(nScaleV+"", ftScale);
                float fX = nBorderLeft-sizeF.Width+1;
                float fY = nScaleV-sizeF.Height;
                g.DrawString(nScaleV+"", ftScale, Brushes.Black, fX, fY);
                nScaleV =i*nScaleVSpace;
            }

            

            return dst;
        }
        public virtual void Draw(Graphics g, ISegyFile segyFile)
        {
            if (segyFile.Traces == null)
            {
                return;
            }
            dynamic range = FindRange(segyFile.Traces);
            var inlineNumbers = GetInlineNumbers(segyFile);
            if (inlineNumbers.Count()==1)
                Draw(g, segyFile.Traces, range);
            else
            {
                Draw(g, segyFile.Traces, range);
            }
                //    dynamic range = FindRange(segyFile.Traces);
                //WriteBitmapPerInline(segyFile, path, inlineNumbers, range);
                //}
            }
        private void Draw(Graphics g, IEnumerable<ITrace> traces, ValueRange range)
        {
            int nCOunt = traces.Count();
            for (int i=0;i<nCOunt; i++)
            {
                Draw(g,i, traces.ElementAt(i), range);
            }
        }
        private void Draw(Graphics g,int traceIndex, ITrace trace, dynamic range)
        {
            float fA = 4f;// 振幅系数
            float fOffsetX = (traceIndex+0.5f)*TraceWidth;
            int nCount = trace.Values.Count;
            PointF[] lstValue = new PointF[nCount];
            float fX = 0;
            List<PointF> lstFill = new List<PointF>();
            float fV0 = fOffsetX+(-range.Min/range.Delta*TraceWidth-0.5f*TraceWidth)*fA;
            float fLastX = 0;
            float fLastY = 0;
            for (int i = 0; i<nCount; i++)
            {
                fLastX=trace.Values[i];
                fLastY=TransDongying(i);
               // fLastY=i;
                if (float.IsInfinity(fLastX))
                {
                    fLastX=0;
                }
                fX=fOffsetX+((fLastX-range.Min)/range.Delta*TraceWidth-0.5f*TraceWidth)*fA;
                
                lstValue[i]=new PointF(fX, fLastY);
                if (trace.Values[i]>0)
                {
                    if (lstFill.Count==0&&i>0)
                    {
                        float fY;
                        CrossByX(lstValue[i-1], lstValue[i], fV0, out fY);
                        lstFill.Add(new PointF(fV0, fY));
                    }
                    lstFill.Add(new PointF(fX, fLastY));
                }
                else
                {
                    if (lstFill.Count>0)
                    {
                        float fY;
                        CrossByX(lstValue[i-1], lstValue[i], fV0, out fY);

                        lstFill.Add(new PointF(fV0, fY));
                        g.FillPolygon(DrawBrush, lstFill.ToArray());
                        lstFill.Clear();
                    }
                }
            }
            //string ssLine = Pts2String(new List<PointF>(lstValue));
            g.DrawLines(DrawPen, lstValue);
        }
        public float TransDongying(int traceIndex)
        {
            int t = traceIndex;
            double dD = (Math.Exp(0.000244*t)-1)*3846.1538;
            return (float)dD;
        }
        public static bool CrossByX(PointF pt1, PointF pt2, float fX, out float fY)
        {
            fY=0f;
            if ((pt1.X-fX)*(pt2.X-fX)<=0)
            {
                if (pt1.Y==pt2.Y)
                {
                    fY=pt1.Y;
                }
                else
                {
                    fY=((fX-pt1.X)/(pt2.X-pt1.X))*(pt2.Y-pt1.Y)+pt1.Y;
                    
                }
                return true;
            }
            return false;
        }
        private float TransValue(float souceValue, float offsetX, float width, ValueRange range)
        {
            return offsetX+(range.Delta/width)*(souceValue-range.Min);
        }
        private static IEnumerable<int> GetInlineNumbers(ISegyFile segyFile)
        {
            return segyFile.Traces.Select(t =>
            {
                if (t.Header==null)
                    return 0;
                return t.Header.InlineNumber;
            }
            ).Distinct();
        }
        public static string Pts2String(List<PointF> pts)
        {
            StringBuilder strb = new StringBuilder();
            for (int i = 0; i<pts.Count; i++)
            {
                strb.Append(pts[i].X+","+pts[i].Y+"\r\n");
            }
            return strb.ToString();
        }
    }
}