using System;

using System.ComponentModel;

using System.Drawing;

using System.Drawing.Drawing2D;

using System.Drawing.Text;

using CSCore.DSP;

namespace Visualization

{

    public class LineSpectrum : SpectrumBase

    {

        private int _barCount;

        private double _barSpacing;

        private double _barWidth;

        private Size _currentSize;

        public LineSpectrum(FftSize fftSize)

        {

            FftSize = fftSize;            

        }

        [Browsable(false)]

        public double BarWidth

        {

            get { return _barWidth; }

        }

        public double BarSpacing

        {

            get { return _barSpacing; }

            set

            {

                if (value < 0)

                    throw new ArgumentOutOfRangeException("value");

                _barSpacing = value;

                UpdateFrequencyMapping();

                RaisePropertyChanged("BarSpacing");

                RaisePropertyChanged("BarWidth");

            }

        }

        public int BarCount

        {

            get { return _barCount; }

            set

            {

                if (value <= 0)

                    throw new ArgumentOutOfRangeException("value");

                _barCount = value;

                SpectrumResolution = value;

                UpdateFrequencyMapping();

                RaisePropertyChanged("BarCount");

                RaisePropertyChanged("BarWidth");

            }

        }

        [BrowsableAttribute(false)]

        public Size CurrentSize

        {

            get { return _currentSize; }

            protected set

            {

                _currentSize = value;

                RaisePropertyChanged("CurrentSize");

            }

        }

        /// <summary>

        /// Update our math.

        /// </summary>

        /// <returns></returns>

        public bool Update()

        {

            return SpectrumProvider.GetFftData(iFftBuffer, this);

        }

        private bool CreateSpectrumLine(Image aImage, Brush brush, Color background, bool highQuality)

        {

            //get the fft result from the spectrum provider            

            using (var pen = new Pen(brush, (float)_barWidth))

            {

                using (Graphics graphics = Graphics.FromImage(aImage))

                {

                    PrepareGraphics(graphics, highQuality);

                    graphics.Clear(background);

                    CreateSpectrumLineInternal(graphics, pen, iFftBuffer, aImage.Size);

                }

            }

            return true;         

        }

        /// <summary>

        /// 

        /// </summary>

        /// <param name="size"></param>

        /// <param name="color1"></param>

        /// <param name="color2"></param>

        /// <param name="background"></param>

        /// <param name="highQuality"></param>

        /// <returns></returns>

        public bool Render(Image aImage, Color color1, Color color2, Color background, bool highQuality)

        {

            if (!UpdateFrequencyMappingIfNessesary(aImage.Size))

            {

                return false;

            }

            using (Brush brush = new LinearGradientBrush(new RectangleF(0, 0, (float)_barWidth, aImage.Size.Height), color2, color1, LinearGradientMode.Vertical))

            {

                return CreateSpectrumLine(aImage, brush, background, highQuality);

            }

        }

        /// <summary>

        /// 

        /// </summary>

        /// <param name="graphics"></param>

        /// <param name="pen"></param>

        /// <param name="fftBuffer"></param>

        /// <param name="size"></param>

        private void CreateSpectrumLineInternal(Graphics graphics, Pen pen, float[] fftBuffer, Size size)

        {

            int height = size.Height;

            //prepare the fft result for rendering 

            SpectrumPointData[] spectrumPoints = CalculateSpectrumPoints(height, fftBuffer);

            //connect the calculated points with lines

            for (int i = 0; i < spectrumPoints.Length; i++)

            {

                SpectrumPointData p = spectrumPoints[i];

                int barIndex = p.SpectrumPointIndex;

                double xCoord = BarSpacing * (barIndex + 1) + (_barWidth * barIndex) + _barWidth / 2;

                var p1 = new PointF((float)xCoord, height);

                var p2 = new PointF((float)xCoord, height - (float)p.Value);

                graphics.DrawLine(pen, p1, p2);

            }

        }

        protected override void UpdateFrequencyMapping()

        {

            _barWidth = Math.Max(((_currentSize.Width - (BarSpacing * (BarCount + 1))) / BarCount), 0.00001);

            base.UpdateFrequencyMapping();

        }

        private bool UpdateFrequencyMappingIfNessesary(Size newSize)

        {

            if (newSize != CurrentSize)

            {

                CurrentSize = newSize;

                UpdateFrequencyMapping();

            }

            return newSize.Width > 0 && newSize.Height > 0;

        }

        private void PrepareGraphics(Graphics graphics, bool highQuality)

        {

            if (highQuality)

            {

                graphics.SmoothingMode = SmoothingMode.AntiAlias;

                graphics.CompositingQuality = CompositingQuality.AssumeLinear;

                graphics.PixelOffsetMode = PixelOffsetMode.Default;

                graphics.TextRenderingHint = TextRenderingHint.ClearTypeGridFit;

            }

            else

            {

                graphics.SmoothingMode = SmoothingMode.HighSpeed;

                graphics.CompositingQuality = CompositingQuality.HighSpeed;

                graphics.PixelOffsetMode = PixelOffsetMode.None;

                graphics.TextRenderingHint = TextRenderingHint.SingleBitPerPixelGridFit;

            }

        }

    }

}