using System;

using System.Collections.Generic;

using System.Linq;

using System.Runtime.InteropServices;

using ESRI.ArcGIS.ADF;

using ESRI.ArcGIS.ArcMapUI;

using ESRI.ArcGIS.Carto;

using ESRI.ArcGIS.Display;

using ESRI.ArcGIS.esriSystem;

using ESRI.ArcGIS.Geometry;

using ESRI.ArcGIS.Geodatabase;



namespace GraticuleCustomLayers

{

    /// <summary>

    /// 

    /// </summary>

    [Guid("b4244d63-a4f0-4649-bd96-88238b63b0f3")]

    [ClassInterface(ClassInterfaceType.None)]

    [ProgId("GraticuleCustomLayers.MGA94GraticuleCustomLayer")]

    public class MGA94GraticuleCustomLayer : ILayer, IGeoDataset, IPersistVariant

    {

        #region Module Level Variables and Constants

 

        // The default densify value used when densifying lines prior to projecting a line

        private const int DensifySegmentCount = 50;



        // MGA Grid spacing

        private const int MGAGridSpacing = 1000;



        // MGA Grid max scale (the MGA grid will be shown below this scale)

        private const double MGAGridMaxScale = 101000;



        // MGA Grid label scale boundary (the MGA grid will have additional labels shown below this scale)

        private const double MGAGridLabelScaleBoundary = 50000.5;



        /// <summary>

        /// Name of the layer

        /// </summary>

        public static readonly string LayerName = "MGA94 Graticule";



        /// <summary>

        /// Indicates if the layer needs its own display cache.

        /// </summary>

        private bool m_isCached = false;



        /// <summary>

        /// Indicates if the layer is currently visible.

        /// </summary>

        private bool m_visible = true;



        /// <summary>

        /// Describes the area of interest of the layer.

        /// </summary>

        private IEnvelope m_areaOfInterest = SpatialReferenceStore.Instance.ExtentMGAZone55.Envelope;



        #endregion



        #region Constructors



        // None



        #endregion



        #region ILayer Members



        /// <summary>

        /// The default area of interest for the layer.

        /// </summary>

        public IEnvelope AreaOfInterest

        {

            get

            {

                return m_areaOfInterest;

            }

        }



        /// <summary>

        /// Indicates if the layer needs its own display cache.

        /// </summary>

        public bool Cached

        {

            get

            {

                return m_isCached;

            }

            set

            {

                m_isCached = value;

            }

        }



        /// <summary>

        /// Draws the layer to the specified display for the given draw phase.

        /// </summary>

        /// <param name="DrawPhase"></param>

        /// <param name="Display"></param>

        /// <param name="TrackCancel"></param>

        public void Draw(esriDrawPhase DrawPhase, IDisplay Display, ITrackCancel TrackCancel)

        {

            System.Diagnostics.Debug.WriteLine("GraticuleDrawEvent");

            using (ComReleaser comReleaser = new ComReleaser())

            {

                // Make sure we can proceed, if not exit

                if (!Valid || !Visible) { return; }



                // Get the display transformation and spatial reference

                IDisplayTransformation displayTranformation = Display.DisplayTransformation;

                ISpatialReference displaySpatialReference = displayTranformation.SpatialReference;

                comReleaser.ManageLifetime(displaySpatialReference);

                if (SpatialReferenceStore.IsUnknownSpatialReference(displaySpatialReference)) { return; }



                // Get the bounds of the map.

                IEnvelope mapBounds = displayTranformation.FittedBounds;



                // Check if we should be drawing anything at all based on scale

                if (displayTranformation.ScaleRatio > MGA94GraticuleCustomLayer.MGAGridMaxScale) { return; }



                // Get the list of lines and label points to be displayed (calculated in graticule coords, returned in display coords)

                List<GraticuleLine> graticuleLines54 = CalculateGraticuleLines(mapBounds, displaySpatialReference, SpatialReferenceStore.Instance.ExtentMGAZone54);

                List<GraticuleLine> graticuleLines55 = CalculateGraticuleLines(mapBounds, displaySpatialReference, SpatialReferenceStore.Instance.ExtentMGAZone55);

                List<GraticuleLine> graticuleLines56 = CalculateGraticuleLines(mapBounds, displaySpatialReference, SpatialReferenceStore.Instance.ExtentMGAZone56);

                List<GraticuleLine> graticuleLines = new List<GraticuleLine>();

                if (graticuleLines54 != null) { graticuleLines.AddRange(graticuleLines54); }

                if (graticuleLines55 != null) { graticuleLines.AddRange(graticuleLines55); }

                if (graticuleLines56 != null) { graticuleLines.AddRange(graticuleLines56); }



                // Make sure we have something to draw

                if (graticuleLines.Count == 0) { return; }



                // Draw the lines

                Display.SetSymbol((ISymbol)GraticuleGraphics.MGA94GraticuleLineSymbol);

                foreach (GraticuleLine graticuleLine in graticuleLines)

                {

                    Display.DrawPolyline((IGeometry)graticuleLine.Line);

                }



                // Hold some x values to help with label collision calculations

                double topBoundsCheck = 0;

                double bottomBoundsCheck = 0;

                int topCount = 0;

                int bottomCount = 0;

                int leftCount = 0;

                int rightCount = 0;



                // Draw the labels

                ITextSymbol textSymbol = GraticuleGraphics.MGA94GraticuleTextSymbol;

                foreach (GraticuleLine graticuleLine in graticuleLines)

                {

                    foreach (GraticuleLabelPoint graticuleLabelPoint in graticuleLine.LabelPoints)

                    {

                        // Set the properties of the text symbol based on the properties of the label point

                        textSymbol.HorizontalAlignment = graticuleLabelPoint.HorizontalAlignment;

                        textSymbol.VerticalAlignment = graticuleLabelPoint.VerticalAlignment;

                        textSymbol.Text = graticuleLabelPoint.Text;



                        // Work out the extent of the label to be drawn

                        IEnvelope boundsEnv = new EnvelopeClass();

                        comReleaser.ManageLifetime(boundsEnv);

                        ((IQueryGeometry)textSymbol).QueryEnvelope(Display.hDC, (ITransformation)displayTranformation, (IGeometry)graticuleLabelPoint.AnchorPoint, boundsEnv);

                        

                        // Do some calcs to make sure we only draw lables that not too close to the corners of the display.

                        bool draw = false;

                        if (textSymbol.VerticalAlignment == esriTextVerticalAlignment.esriTVATop) // Top labels

                        {

                            if (boundsEnv.XMin > (mapBounds.XMin + (boundsEnv.Width / 2D)) && boundsEnv.XMax < (mapBounds.XMax - (boundsEnv.Width / 2D)) && boundsEnv.XMin > topBoundsCheck)

                            {

                                if (displayTranformation.ScaleRatio > MGA94GraticuleCustomLayer.MGAGridLabelScaleBoundary)

                                {

                                    topCount += 1;

                                    if (IsOdd(topCount))

                                    {

                                        topBoundsCheck = boundsEnv.XMax;

                                        draw = true;

                                    }

                                }

                                else

                                {

                                    topBoundsCheck = boundsEnv.XMax;

                                    draw = true;

                                }

                            }

                        }

                        else if (textSymbol.VerticalAlignment == esriTextVerticalAlignment.esriTVABottom) // Bottom labels

                        {

                            if (boundsEnv.XMin > (mapBounds.XMin + (boundsEnv.Width / 2D)) && boundsEnv.XMax < (mapBounds.XMax - (boundsEnv.Width / 2D)) && boundsEnv.XMin > bottomBoundsCheck)

                            {

                                if (displayTranformation.ScaleRatio > MGA94GraticuleCustomLayer.MGAGridLabelScaleBoundary)

                                {

                                    bottomCount += 1;

                                    if (IsOdd(bottomCount))

                                    {

                                        bottomBoundsCheck = boundsEnv.XMax;

                                        draw = true;

                                    }

                                }

                                else

                                {

                                    bottomBoundsCheck = boundsEnv.XMax;

                                    draw = true;

                                }

                            }

                        }

                        else if (textSymbol.HorizontalAlignment == esriTextHorizontalAlignment.esriTHALeft) // Left labels

                        {

                            if ((mapBounds.YMax - boundsEnv.YMax) > boundsEnv.Height &&

                                (boundsEnv.YMin - mapBounds.YMin) > boundsEnv.Height)

                            {

                                if (displayTranformation.ScaleRatio > MGA94GraticuleCustomLayer.MGAGridLabelScaleBoundary)

                                {

                                    leftCount += 1;

                                    if (IsOdd(leftCount))

                                    {

                                        draw = true;

                                    }

                                }

                                else

                                {

                                    draw = true;

                                }

                            }

                        }

                        else // Right labels

                        {

                            if ((mapBounds.YMax - boundsEnv.YMax) > boundsEnv.Height &&

                                (boundsEnv.YMin - mapBounds.YMin) > boundsEnv.Height)

                            {

                                if (displayTranformation.ScaleRatio > MGA94GraticuleCustomLayer.MGAGridLabelScaleBoundary)

                                {

                                    rightCount += 1;

                                    if (IsOdd(rightCount))

                                    {

                                        draw = true;

                                    }

                                }

                                else

                                {

                                    draw = true;

                                }

                            }

                        }



                        // If the label is to be drawn, the draw it

                        if (draw)

                        {

                            Display.SetSymbol((ISymbol)textSymbol);

                            Display.DrawText((IGeometry)graticuleLabelPoint.AnchorPoint, graticuleLabelPoint.Text);

                        }

                        ComReleaser.ReleaseCOMObject(graticuleLabelPoint.AnchorPoint);

                    }

                    ComReleaser.ReleaseCOMObject(graticuleLine.Line);

                }

            }

        }



        /// <summary>

        /// Maximum scale (representative fraction) at which the layer will display.

        /// </summary>

        public double MaximumScale

        {

            get

            {

                return default(double);

            }

            set

            {

                // Setting MaximumScale does nothing

            }

        }



        /// <summary>

        /// Minimum scale (representative fraction) at which the layer will display.

        /// </summary>

        public double MinimumScale

        {

            get

            {

                return default(double);

            }

            set

            {

                // Setting MinimumScale does nothing

            }

        }



        /// <summary>

        /// Layer name.

        /// </summary>

        public string Name

        {

            get

            {

                return LayerName;

            }

            set

            {

                // Setting Name does nothing

            }

        }



        /// <summary>

        /// Indicates if the layer shows map tips.

        /// </summary>

        public bool ShowTips

        {

            get

            {

                return default(bool);

            }

            set

            {

                // Setting ShowTips does nothing

            }

        }



        /// <summary>

        /// Spatial reference for the layer.

        /// </summary>

        public ISpatialReference SpatialReference

        {

            set

            {

                // Setting SpatialReference does nothing

            }

        }



        /// <summary>

        /// Supported draw phases.

        /// </summary>

        public int SupportedDrawPhases

        {

            get

            {

                return (int)esriDrawPhase.esriDPGeography;

            }

        }



        /// <summary>

        /// Indicates if the layer is currently valid.

        /// </summary>

        public bool Valid

        {

            get

            {

                return true;

            }

        }



        /// <summary>

        /// Indicates if the layer is currently visible.

        /// </summary>

        public bool Visible

        {

            get

            {

                return m_visible;

            }

            set

            {

                m_visible = value;

            }

        }



        /// <summary>

        /// Get_s the tip text.

        /// </summary>

        /// <param name="x">The x.</param>

        /// <param name="y">The y.</param>

        /// <param name="Tolerance">The tolerance.</param>

        public string get_TipText(double x, double y, double Tolerance)

        {

            return default(string);

        }



        #endregion



        #region IGeoDataset Members



        IEnvelope IGeoDataset.Extent

        {

            get { return m_areaOfInterest; }

        }



        ISpatialReference IGeoDataset.SpatialReference

        {

            get { return m_areaOfInterest.SpatialReference; }

        }



        #endregion



        #region IPersistVariant Members



        public ESRI.ArcGIS.esriSystem.UID ID

        {

            get

            {

                UID typeID = new UIDClass();

                typeID.Value = GetType().GUID.ToString("B");

                return typeID;

            }

        }



        public void Load(ESRI.ArcGIS.esriSystem.IVariantStream Stream)

        {

            // TODO: Add ArcGISClass1.Load implementation

        }



        public void Save(ESRI.ArcGIS.esriSystem.IVariantStream Stream)

        {

            // TODO: Add ArcGISClass1.Save implementation

        }



        #endregion



        #region Static Helper Methods



        /// <summary>

        /// Calculates the graticule lines.

        /// </summary>

        /// <param name="displayBounds">The display bounds.</param>

        /// <param name="displaySpatialReference">The display spatial reference.</param>

        /// <param name="mgaZoneExtent">The mga zone extent.</param>

        /// <returns>

        /// A list of GraticuleLine DTOs

        /// </returns>

        private static List<GraticuleLine> CalculateGraticuleLines(IEnvelope displayBounds, ISpatialReference displaySpatialReference, IPolygon mgaZoneExtent)

        {

            using (ComReleaser comReleaser = new ComReleaser())

            {

                // Turn the display bounds in a polygon, densify it and project it to same spatial reference as the mga zone we are dealing with

                IPolygon displayBoundsPolyMga = new PolygonClass();

                comReleaser.ManageLifetime(displayBoundsPolyMga);

                ((IPointCollection)displayBoundsPolyMga).AddPoint(displayBounds.UpperLeft);

                ((IPointCollection)displayBoundsPolyMga).AddPoint(displayBounds.UpperRight);

                ((IPointCollection)displayBoundsPolyMga).AddPoint(displayBounds.LowerRight);

                ((IPointCollection)displayBoundsPolyMga).AddPoint(displayBounds.LowerLeft);

                displayBoundsPolyMga.Close();

                displayBoundsPolyMga.SpatialReference = displayBounds.SpatialReference;

                ((IPolycurve)displayBoundsPolyMga).Densify(displayBoundsPolyMga.Length / Convert.ToDouble(MGA94GraticuleCustomLayer.DensifySegmentCount), 0);

                displayBoundsPolyMga = (IPolygon)ProjectionMethods.Project(displayBoundsPolyMga, mgaZoneExtent.SpatialReference);

                

                // Determine the extent that is common between the zone extent and the display bounds

                IPolygon graticuleBoundsPolyMga = (IPolygon)((ITopologicalOperator)mgaZoneExtent).Intersect(displayBoundsPolyMga, esriGeometryDimension.esriGeometry2Dimension);

                comReleaser.ManageLifetime(graticuleBoundsPolyMga);



                // Make sure we have at least some common area

                if (graticuleBoundsPolyMga.IsEmpty) { return null; }



                // Make an envelope that covers the graticule polygon extent

                IEnvelope graticuleBoundsMga = graticuleBoundsPolyMga.Envelope;

                comReleaser.ManageLifetime(graticuleBoundsMga);

                graticuleBoundsMga.Expand(1.25, 1.25, true);



                // Work out how many vertical and horizontal grid lines are going to have 



                // Make an envelope slightly smaller than the display bounds to use for calculating labels

                IEnvelope displayBoundsReduced = (IEnvelope)((IClone)displayBounds).Clone();

                comReleaser.ManageLifetime(displayBoundsReduced);

                displayBoundsReduced.Expand(0.9975, 0.9975, true);



                // Get the edges of the reduced display bounds in display coordinates

                object missing = Type.Missing;

                IPointCollection displayBoundsTopEdge = new PolylineClass();

                comReleaser.ManageLifetime(displayBoundsTopEdge);

                ((IPolyline)displayBoundsTopEdge).SpatialReference = displaySpatialReference;

                displayBoundsTopEdge.AddPoint(displayBoundsReduced.UpperLeft, ref missing, ref missing);

                displayBoundsTopEdge.AddPoint(displayBoundsReduced.UpperRight, ref missing, ref missing);

                IPointCollection displayBoundsBottomEdge = new PolylineClass();

                comReleaser.ManageLifetime(displayBoundsBottomEdge);

                ((IPolyline)displayBoundsBottomEdge).SpatialReference = displaySpatialReference;

                displayBoundsBottomEdge.AddPoint(displayBoundsReduced.LowerLeft, ref missing, ref missing);

                displayBoundsBottomEdge.AddPoint(displayBoundsReduced.LowerRight, ref missing, ref missing);

                IPointCollection displayBoundsLeftEdge = new PolylineClass();

                comReleaser.ManageLifetime(displayBoundsLeftEdge);

                ((IPolyline)displayBoundsLeftEdge).SpatialReference = displaySpatialReference;

                displayBoundsLeftEdge.AddPoint(displayBoundsReduced.LowerLeft, ref missing, ref missing);

                displayBoundsLeftEdge.AddPoint(displayBoundsReduced.UpperLeft, ref missing, ref missing);

                IPointCollection displayBoundsRightEdge = new PolylineClass();

                comReleaser.ManageLifetime(displayBoundsRightEdge);

                ((IPolyline)displayBoundsRightEdge).SpatialReference = displaySpatialReference;

                displayBoundsRightEdge.AddPoint(displayBoundsReduced.LowerRight, ref missing, ref missing);

                displayBoundsRightEdge.AddPoint(displayBoundsReduced.UpperRight, ref missing, ref missing);



                // Calc the starting cooordinates to build the grid lines

                int remainder = 0;

                int eastingLeft = Math.DivRem(Convert.ToInt32(graticuleBoundsMga.XMin), MGA94GraticuleCustomLayer.MGAGridSpacing, out remainder) * MGA94GraticuleCustomLayer.MGAGridSpacing;

                int northingBottom = Math.DivRem(Convert.ToInt32(graticuleBoundsMga.YMin), MGA94GraticuleCustomLayer.MGAGridSpacing, out remainder) * MGA94GraticuleCustomLayer.MGAGridSpacing;



                // Create the graticule lines (extend to expanded bounds), project back to the display coordinates and calculate label points

                List<GraticuleLine> graticuleLines = new List<GraticuleLine>();

                for (int i = eastingLeft; i <= graticuleBoundsMga.XMax; i += MGA94GraticuleCustomLayer.MGAGridSpacing)

                {

                    IPoint lineStart = new PointClass();

                    comReleaser.ManageLifetime(lineStart);

                    IPoint lineEnd = new PointClass();

                    comReleaser.ManageLifetime(lineEnd);

                    lineStart.PutCoords(i, graticuleBoundsMga.YMin);

                    lineEnd.PutCoords(i, graticuleBoundsMga.YMax);

                    IPolyline verticalLineFull = new PolylineClass();

                    comReleaser.ManageLifetime(verticalLineFull);

                    verticalLineFull.SpatialReference = mgaZoneExtent.SpatialReference;

                    verticalLineFull.FromPoint = lineStart;

                    verticalLineFull.ToPoint = lineEnd;

                    IPolyline verticalLine = (IPolyline)((ITopologicalOperator)verticalLineFull).Intersect((IGeometry)graticuleBoundsPolyMga, esriGeometryDimension.esriGeometry1Dimension);

                    if (verticalLine != null && verticalLine.IsEmpty == false)

                    {

                        ((IPolycurve)verticalLine).Densify(verticalLine.Length / Convert.ToDouble(MGA94GraticuleCustomLayer.DensifySegmentCount), 0);

                        verticalLine = (IPolyline)ProjectionMethods.Project((IGeometry)verticalLine, displaySpatialReference);



                        // Intersect the lines with the display bounds (top and bottom)

                        List<GraticuleLabelPoint> graticuleLabelPoints = new List<GraticuleLabelPoint>();

                        IGeometry topLabelPoint = ((ITopologicalOperator)verticalLine).Intersect((IGeometry)displayBoundsTopEdge, esriGeometryDimension.esriGeometry0Dimension);

                        if ((topLabelPoint as IMultipoint) != null && ((IPointCollection)topLabelPoint).PointCount == 1)

                        {

                            graticuleLabelPoints.Add(new GraticuleLabelPoint(((IPointCollection)topLabelPoint).get_Point(0),

                                esriTextHorizontalAlignment.esriTHACenter, esriTextVerticalAlignment.esriTVATop, "<FNT scale='80'>" + mgaPrefix(i, MGA94GraticuleCustomLayer.MGAGridSpacing) + "</FNT>" + "<FNT scale='60'> </FNT>" + mgaSuffix(i, MGA94GraticuleCustomLayer.MGAGridSpacing) +

                                System.Environment.NewLine + "<FNT scale='80'>" + "z" + mgaZoneExtent.SpatialReference.Name.Substring(mgaZoneExtent.SpatialReference.Name.IndexOf("_Zone_") + 6, 2) + "</FNT>"));

                        }

                        IGeometry bottomLabelPoint = ((ITopologicalOperator)verticalLine).Intersect((IGeometry)displayBoundsBottomEdge, esriGeometryDimension.esriGeometry0Dimension);

                        if ((bottomLabelPoint as IMultipoint) != null && ((IPointCollection)bottomLabelPoint).PointCount == 1)

                        {

                            graticuleLabelPoints.Add(new GraticuleLabelPoint(((IPointCollection)bottomLabelPoint).get_Point(0),

                                esriTextHorizontalAlignment.esriTHACenter, esriTextVerticalAlignment.esriTVABottom, "<FNT scale='80'>" + mgaPrefix(i, MGA94GraticuleCustomLayer.MGAGridSpacing) + "</FNT>" + "<FNT scale='60'> </FNT>" + mgaSuffix(i, MGA94GraticuleCustomLayer.MGAGridSpacing)));

                        }

                        graticuleLines.Add(new GraticuleLine(verticalLine, graticuleLabelPoints));

                    }

                }

                for (int i = northingBottom; i <= graticuleBoundsMga.YMax; i += MGA94GraticuleCustomLayer.MGAGridSpacing)

                {

                    IPoint lineStart = new PointClass();

                    comReleaser.ManageLifetime(lineStart);

                    IPoint lineEnd = new PointClass();

                    comReleaser.ManageLifetime(lineEnd);

                    lineStart.PutCoords(graticuleBoundsMga.XMin, i);

                    lineEnd.PutCoords(graticuleBoundsMga.XMax, i);

                    IPolyline horizontalLineFull = new PolylineClass();

                    comReleaser.ManageLifetime(horizontalLineFull);

                    horizontalLineFull.SpatialReference = mgaZoneExtent.SpatialReference;

                    horizontalLineFull.FromPoint = lineStart;

                    horizontalLineFull.ToPoint = lineEnd;

                    IPolyline horizontalLine = (IPolyline)((ITopologicalOperator)horizontalLineFull).Intersect((IGeometry)graticuleBoundsPolyMga, esriGeometryDimension.esriGeometry1Dimension);

                    if (horizontalLine != null && horizontalLine.IsEmpty == false)

                    {

                        ((IPolycurve)horizontalLine).Densify(horizontalLine.Length / Convert.ToDouble(MGA94GraticuleCustomLayer.DensifySegmentCount), 0);

                        horizontalLine = (IPolyline)ProjectionMethods.Project((IGeometry)horizontalLine, displaySpatialReference);



                        // Intersect the lines with the display bounds (top and bottom)

                        List<GraticuleLabelPoint> graticuleLabelPoints = new List<GraticuleLabelPoint>();

                        IGeometry leftLabelPoint = ((ITopologicalOperator)horizontalLine).Intersect((IGeometry)displayBoundsLeftEdge, esriGeometryDimension.esriGeometry0Dimension);

                        if ((leftLabelPoint as IMultipoint) != null && ((IPointCollection)leftLabelPoint).PointCount == 1)

                        {

                            graticuleLabelPoints.Add(new GraticuleLabelPoint(((IPointCollection)leftLabelPoint).get_Point(0),

                                esriTextHorizontalAlignment.esriTHALeft, esriTextVerticalAlignment.esriTVACenter, "<FNT scale='80'>" + mgaPrefix(i, MGA94GraticuleCustomLayer.MGAGridSpacing) + "</FNT>" + "<FNT scale='60'> </FNT>" + mgaSuffix(i, MGA94GraticuleCustomLayer.MGAGridSpacing)));

                        }

                        IGeometry rightLabelPoint = ((ITopologicalOperator)horizontalLine).Intersect((IGeometry)displayBoundsRightEdge, esriGeometryDimension.esriGeometry0Dimension);

                        if ((rightLabelPoint as IMultipoint) != null && ((IPointCollection)rightLabelPoint).PointCount == 1)

                        {

                            graticuleLabelPoints.Add(new GraticuleLabelPoint(((IPointCollection)rightLabelPoint).get_Point(0),

                                esriTextHorizontalAlignment.esriTHARight, esriTextVerticalAlignment.esriTVACenter, "<FNT scale='80'>" + mgaPrefix(i, MGA94GraticuleCustomLayer.MGAGridSpacing) + "</FNT>" + "<FNT scale='60'> </FNT>" + mgaSuffix(i, MGA94GraticuleCustomLayer.MGAGridSpacing)));

                        }

                        graticuleLines.Add(new GraticuleLine(horizontalLine, graticuleLabelPoints));

                    }

                }

                return graticuleLines;

            }

        }



        /// <summary>

        /// Calculates the mag prefix for a label based on grid spacing.

        /// </summary>

        /// <param name="mgaValue">The mga value.</param>

        /// <param name="gridSpacing">The grid spacing.</param>

        /// <returns>The prefix string.</returns>

        private static string mgaPrefix(int mgaValue, int gridSpacing)

        {

            int result;

            string wholeValue = Math.DivRem(mgaValue, gridSpacing, out result).ToString();

            return wholeValue.Substring(0, (wholeValue.Length - 2));

        }



        /// <summary>

        /// Calculates the mag suffix for a label based on grid spacing.

        /// </summary>

        /// <param name="mgaValue">The mga value.</param>

        /// <param name="gridSpacing">The grid spacing.</param>

        /// <returns>The prefix string.</returns>

        private static string mgaSuffix(int mgaValue, int gridSpacing)

        {

            int result;

            string wholeValue = Math.DivRem(mgaValue, gridSpacing, out result).ToString();

            return wholeValue.Substring((wholeValue.Length - 2), 2);

        }



        /// <summary>

        /// Determines whether the specified int value is odd.

        /// </summary>

        /// <param name="intValue">The int value.</param>

        /// <returns>

        ///   <c>true</c> if the specified int value is odd; otherwise, <c>false</c>.

        /// </returns>

        public static bool IsOdd(int intValue)

        {

            return ((intValue & 1) == 1);

        }



        #endregion



        #region Data Transfer Objects



        /// <summary>

        /// Class to hold details of a graticule line

        /// </summary>

        private class GraticuleLine

        {

            #region Module Level Variables



            private IPolyline _line;



            private List<GraticuleLabelPoint> _labelPoints;



            #endregion



            #region Constructors



            /// <summary>

            /// Initializes a new instance of the <see cref="GraticuleLine"/> class.

            /// </summary>

            /// <param name="line">The line.</param>

            /// <param name="labelPoints">The label points.</param>

            public GraticuleLine(IPolyline line, List<GraticuleLabelPoint> labelPoints)

            {

                _line = line;

                _labelPoints = labelPoints;

            }



            #endregion



            #region Properties



            /// <summary>

            /// Gets the line.

            /// </summary>

            /// <value>The line.</value>

            public IPolyline Line

            {

                get { return _line; }

            }



            /// <summary>

            /// Gets the label points.

            /// </summary>

            /// <value>The label points.</value>

            public List<GraticuleLabelPoint> LabelPoints

            {

                get { return _labelPoints; }

            }



            #endregion

        }



        /// <summary>

        /// Class to hold details of a graticule label point

        /// </summary>

        private class GraticuleLabelPoint

        {

            #region Module Level Variables



            private IPoint _anchorPoint;



            private esriTextHorizontalAlignment _horizontalAlignment;



            private esriTextVerticalAlignment _verticalAlignment;



            private string _text;



            #endregion



            #region Constructors



            /// <summary>

            /// Initializes a new instance of the <see cref="GraticuleLabelPoint"/> class.

            /// </summary>

            /// <param name="anchorPoint">The anchor point.</param>

            /// <param name="horizontalAlignment">The horizontal alignment.</param>

            /// <param name="verticalAlignment">The vertical alignment.</param>

            /// <param name="text">The text.</param>

            public GraticuleLabelPoint(IPoint anchorPoint, esriTextHorizontalAlignment horizontalAlignment,

                esriTextVerticalAlignment verticalAlignment, string text)

            {

                _anchorPoint = anchorPoint;

                _horizontalAlignment = horizontalAlignment;

                _verticalAlignment = verticalAlignment;

                _text = text;

            }



            #endregion



            #region Properties



            /// <summary>

            /// Gets the anchor point.

            /// </summary>

            /// <value>The anchor point.</value>

            public IPoint AnchorPoint

            {

                get { return _anchorPoint; }

            }



            /// <summary>

            /// Gets the horizontal alignment.

            /// </summary>

            /// <value>The horizontal alignment.</value>

            public esriTextHorizontalAlignment HorizontalAlignment

            {

                get { return _horizontalAlignment; }

            }



            /// <summary>

            /// Gets the vertical alignment.

            /// </summary>

            /// <value>The vertical alignment.</value>

            public esriTextVerticalAlignment VerticalAlignment

            {

                get { return _verticalAlignment; }

            }



            /// <summary>

            /// Gets the text.

            /// </summary>

            /// <value>The text.</value>

            public string Text

            {

                get { return _text; }

            }



            #endregion

        }

        #endregion

    }

}