using System;
using System.Drawing;
using System.Drawing.Drawing2D;
using System.ComponentModel;
using FastReport.Utils;

namespace FastReport.Gauge.Linear
{
    /// <summary>
    /// Represents a linear scale.
    /// </summary>
#if !DEBUG
    [DesignTimeVisible(false)]
#endif
    public class LinearScale : GaugeScale
    {
        #region Fields

        private float left;
        private float top;
        private float height;
        private float width;
        private int majorTicksNum;

        #endregion // Fields

        #region Properties

        

        #endregion // Properties

        #region Constructors

        /// <summary>
        /// Initializes a new instance of the <see cref="LinearScale"/> class.
        /// </summary>
        /// <param name="parent">The parent gauge object.</param>
        public LinearScale(GaugeObject parent) : base(parent)
        {
            MajorTicks = new ScaleTicks(10, 2, Color.Black);
            MinorTicks = new ScaleTicks(6, 1, Color.Black);
            majorTicksNum = 6;
        }

        #endregion // Constructors

        #region Private Methods

        private void DrawMajorTicksHorz(FRPaintEventArgs e)
        {
            IGraphics g = e.Graphics;
            Pen pen = e.Cache.GetPen(MajorTicks.Color, MajorTicks.Width * e.ScaleX, DashStyle.Solid);
            Brush brush = TextFill.CreateBrush(new RectangleF(Parent.AbsLeft * e.ScaleX, Parent.AbsTop * e.ScaleY,
                Parent.Width * e.ScaleX, Parent.Height * e.ScaleY), e.ScaleX, e.ScaleY);
            float x = left;
            float y1 = top;
            float y2 = top + height;
            float step = width / (majorTicksNum - 1);
            int textStep = (int)((Parent.Maximum - Parent.Minimum) / (majorTicksNum - 1));
            Font font = e.Cache.GetFont(Font.FontFamily, Parent.IsPrinting ? Font.Size : Font.Size * e.ScaleX * 96f / DrawUtils.ScreenDpi, Font.Style);
            string text = Parent.Minimum.ToString();
            float y3 = y1 - 0.4f * Units.Centimeters * e.ScaleY;
            if ((Parent as LinearGauge).Inverted)
            {
                y3 = y2 - g.MeasureString(text, Font).Height + 0.4f * Units.Centimeters * e.ScaleY;
            }
            for (int i = 0; i < majorTicksNum; i++)
            {
                g.DrawLine(pen, x, y1, x, y2);
                SizeF strSize = g.MeasureString(text, Font);
                g.DrawString(text, font, brush, x - strSize.Width / 2 * e.ScaleX / (DrawUtils.ScreenDpi / 96f), y3);
                text = Convert.ToString(textStep * (i + 1) + Parent.Minimum);
                x += step;
            }
            brush.Dispose();
        }

        private void DrawMinorTicksHorz(FRPaintEventArgs e)
        {
            IGraphics g = e.Graphics;
            Pen pen = e.Cache.GetPen(MinorTicks.Color, MinorTicks.Width * e.ScaleX, DashStyle.Solid);
            float x = left;
            float y1 = top + height * 0.2f;
            float y2 = top + height - height * 0.2f;
            float step = width / (majorTicksNum - 1) / 4;
            for (int i = 0; i < majorTicksNum - 1; i++)
            {
                x += step;
                for (int j = 0; j < 3; j++)
                {
                    g.DrawLine(pen, x, y1, x, y2);
                    x += step;
                }
            }
        }

        private void DrawMajorTicksVert(FRPaintEventArgs e)
        {
            IGraphics g = e.Graphics;
            Pen pen = e.Cache.GetPen(MajorTicks.Color, MajorTicks.Width * e.ScaleX, DashStyle.Solid);
            Brush brush = TextFill.CreateBrush(new RectangleF(Parent.AbsLeft * e.ScaleX, Parent.AbsTop * e.ScaleY,
     Parent.Width * e.ScaleX, Parent.Height * e.ScaleY), e.ScaleX, e.ScaleY);
            float y = top + height;
            float x1 = left;
            float x2 = left + width;
            float step = height / (majorTicksNum - 1);
            int textStep = (int)((Parent.Maximum - Parent.Minimum) / (majorTicksNum - 1));
            Font font = e.Cache.GetFont(Font.FontFamily, Parent.IsPrinting ? Font.Size : Font.Size * e.ScaleX * 96f / DrawUtils.ScreenDpi, Font.Style);
            string text = Parent.Minimum.ToString();
            for (int i = 0; i < majorTicksNum; i++)
            {
                g.DrawLine(pen, x1, y, x2, y);
                SizeF strSize = g.MeasureString(text, Font);
                float x3 = x1 - strSize.Width * e.ScaleX / (DrawUtils.ScreenDpi / 96f) - 0.04f * Units.Centimeters * e.ScaleX;
                if ((Parent as LinearGauge).Inverted)
                {
                    x3 = x2 + 0.04f * Units.Centimeters * e.ScaleX;
                }
                g.DrawString(text, font, brush, x3, y - strSize.Height / 2 * e.ScaleY / (DrawUtils.ScreenDpi / 96f));
                text = Convert.ToString(textStep * (i + 1) + Parent.Minimum);
                y -= step;
            }
            brush.Dispose();
        }

        private void DrawMinorTicksVert(FRPaintEventArgs e)
        {
            IGraphics g = e.Graphics;
            Pen pen = e.Cache.GetPen(MinorTicks.Color, MinorTicks.Width * e.ScaleX, DashStyle.Solid);
            float y = top + height;
            float x1 = left + width * 0.2f;
            float x2 = left + width - width * 0.2f;
            float step = height / (majorTicksNum - 1) / 4;
            for (int i = 0; i < majorTicksNum - 1; i++)
            {
                y -= step;
                for (int j = 0; j < 3; j++)
                {
                    g.DrawLine(pen, x1, y, x2, y);
                    y -= step;
                }
            }
        }

        #endregion // Private Methods

        #region Public Methods

        /// <inheritdoc/>
        public override void Assign(GaugeScale src)
        {
            base.Assign(src);

            LinearScale s = src as LinearScale;
            MajorTicks.Assign(s.MajorTicks);
            MinorTicks.Assign(s.MinorTicks);
        }

        /// <inheritdoc/>
        public override void Draw(FRPaintEventArgs e)
        {
            base.Draw(e);

            if (Parent.Vertical)
            {
                left = (Parent.AbsLeft + 0.7f * Units.Centimeters) * e.ScaleX;
                top = (Parent.AbsTop + 0.5f * Units.Centimeters) * e.ScaleY;
                height = (Parent.Height - 1.0f * Units.Centimeters) * e.ScaleY;
                width = (Parent.Width - 1.4f * Units.Centimeters) * e.ScaleX;

                DrawMajorTicksVert(e);
                DrawMinorTicksVert(e);
            }
            else
            {
                left = (Parent.AbsLeft + 0.5f * Units.Centimeters) * e.ScaleX;
                top = (Parent.AbsTop + 0.6f * Units.Centimeters) * e.ScaleY;
                height = (Parent.Height - 1.2f * Units.Centimeters) * e.ScaleY;
                width = (Parent.Width - 1.0f * Units.Centimeters) * e.ScaleX;

                DrawMajorTicksHorz(e);
                DrawMinorTicksHorz(e);
            }
        }

        /// <inheritdoc/>
        public override void Serialize(FRWriter writer, string prefix, GaugeScale diff)
        {
            base.Serialize(writer, prefix, diff);

            LinearScale dc = diff as LinearScale;
            MajorTicks.Serialize(writer, prefix + ".MajorTicks", dc.MajorTicks);
            MinorTicks.Serialize(writer, prefix + ".MinorTicks", dc.MinorTicks);
        }

        #endregion // Public Methods
    }
}