Imported Upstream version 4.6.0.125

Former-commit-id: a2155e9bd80020e49e72e86c44da02a8ac0e57a4

mcs/class/referencesource/System.Data.Entity/System/Data/SqlClient/IDbSpatialValue.cs

@@ -0,0 +1,208 @@
+//------------------------------------------------------------------------------
+// <copyright file="IDbSpatialValue.cs" company="Microsoft">
+//      Copyright (c) Microsoft Corporation.  All rights reserved.
+// </copyright>
+//
+// @owner  willa
+// @backupOwner [....]
+//------------------------------------------------------------------------------
+
+using System.Data.Spatial;
+using System.Data.Metadata.Edm;
+
+namespace System.Data.SqlClient.Internal
+{
+    /// <summary>
+    /// Adapter interface to make working with instances of <see cref="DbGeometry"/> or <see cref="DbGeography"/> easier.  
+    /// Implementing types wrap instances of DbGeography/DbGeometry and allow them to be consumed in a common way. 
+    /// This interface is implemented by wrapping types for two reasons:
+    /// 1. The DbGeography/DbGeometry classes cannot directly implement internal interfaces because their members are virtual (behavior is not guaranteed).
+    /// 2. The wrapping types ensure that instances of IDbSpatialValue handle the <see cref="NotImplementedException"/>s thrown
+    ///    by any unimplemented members of derived DbGeography/DbGeometry types that correspond to the properties and methods declared in the interface.
+    /// </summary>
+    internal interface IDbSpatialValue
+    {
+        bool IsGeography { get; }
+        PrimitiveTypeKind PrimitiveType { get; }
+        object ProviderValue { get; }
+        int? CoordinateSystemId { get; }
+        string WellKnownText { get; }
+        byte[] WellKnownBinary { get; }
+        string GmlString { get; }
+        
+        Exception NotSqlCompatible();
+    }
+
+    internal static class IDbSpatialValueExtensionMethods
+    {
+        /// <summary>
+        /// Returns an instance of <see cref="IDbSpatialValue"/> that wraps the specified <see cref="DbGeography"/> value.
+        /// IDbSpatialValue members are guaranteed not to throw the <see cref="NotImplementedException"/>s caused by unimplemented members of their wrapped values.
+        /// </summary>
+        /// <param name="geographyValue">The geography instance to wrap</param>
+        /// <returns>An instance of <see cref="IDbSpatialValue"/> that wraps the specified geography value</returns>
+        internal static IDbSpatialValue AsSpatialValue(this DbGeography geographyValue)
+        {
+            if (geographyValue == null)
+            {
+                return null;
+            }
+            return new DbGeographyAdapter(geographyValue);
+        }
+
+        /// <summary>
+        /// Returns an instance of <see cref="IDbSpatialValue"/> that wraps the specified <see cref="DbGeometry"/> value.
+        /// IDbSpatialValue members are guaranteed not to throw the <see cref="NotImplementedException"/>s caused by unimplemented members of their wrapped values.
+        /// </summary>
+        /// <param name="geometryValue">The geometry instance to wrap</param>
+        /// <returns>An instance of <see cref="IDbSpatialValue"/> that wraps the specified geometry value</returns>
+        internal static IDbSpatialValue AsSpatialValue(this DbGeometry geometryValue)
+        {
+            if (geometryValue == null)
+            {
+                return null;
+            }
+            return new DbGeometryAdapter(geometryValue);
+        }
+    }
+
+    internal struct DbGeographyAdapter : IDbSpatialValue
+    {
+        private readonly DbGeography value;
+
+        internal DbGeographyAdapter(DbGeography geomValue)
+        {
+            this.value = geomValue;
+        }
+
+        private TResult NullIfNotImplemented<TResult>(Func<DbGeography, TResult> accessor)
+            where TResult : class
+        {
+            try
+            {
+                return accessor(this.value);
+            }
+            catch (NotImplementedException)
+            {
+                return null;
+            }
+        }
+
+        private int? NullIfNotImplemented(Func<DbGeography, int> accessor)
+        {
+            try
+            {
+                return accessor(this.value);
+            }
+            catch (NotImplementedException)
+            {
+                return null;
+            }
+        }
+
+        public bool IsGeography { get { return true; } }
+
+        public PrimitiveTypeKind PrimitiveType { get { return PrimitiveTypeKind.Geography; } }
+
+        public object ProviderValue
+        {
+            get { return NullIfNotImplemented(geog => geog.ProviderValue); }
+        }
+
+        public int? CoordinateSystemId
+        {
+            get { return NullIfNotImplemented(geog => geog.CoordinateSystemId); }
+        }
+
+        public string WellKnownText
+        {
+            get
+            {
+                return NullIfNotImplemented(geog => geog.AsTextIncludingElevationAndMeasure())
+                    ?? NullIfNotImplemented(geog => geog.AsText()); // better than nothing if the provider doesn't support AsTextIncludingElevationAndMeasure
+            }
+        }
+
+        public byte[] WellKnownBinary
+        {
+            get { return NullIfNotImplemented(geog => geog.AsBinary()); }
+        }
+
+        public string GmlString
+        {
+            get { return NullIfNotImplemented(geog => geog.AsGml()); }
+        }
+
+        public Exception NotSqlCompatible() { return EntityUtil.GeographyValueNotSqlCompatible(); }
+    }
+
+    internal struct DbGeometryAdapter : IDbSpatialValue
+    {
+        private readonly DbGeometry value;
+
+        internal DbGeometryAdapter(DbGeometry geomValue)
+        {
+            this.value = geomValue;
+        }
+
+        private TResult NullIfNotImplemented<TResult>(Func<DbGeometry, TResult> accessor)
+            where TResult : class
+        {
+            try
+            {
+                return accessor(this.value);
+            }
+            catch (NotImplementedException)
+            {
+                return null;
+            }
+        }
+
+        private int? NullIfNotImplemented(Func<DbGeometry, int> accessor)
+        {
+            try
+            {
+                return accessor(this.value);
+            }
+            catch (NotImplementedException)
+            {
+                return null;
+            }
+        }
+
+        public bool IsGeography { get { return false; } }
+
+        public PrimitiveTypeKind PrimitiveType { get { return PrimitiveTypeKind.Geometry; } }
+
+        public object ProviderValue
+        {
+            get { return NullIfNotImplemented(geom => geom.ProviderValue); }
+        }
+
+        public int? CoordinateSystemId
+        {
+            get { return NullIfNotImplemented(geom => geom.CoordinateSystemId); }
+        }
+
+        public string WellKnownText
+        {
+            get 
+            {
+                return NullIfNotImplemented(geom => geom.AsTextIncludingElevationAndMeasure())
+                    ?? NullIfNotImplemented(geom => geom.AsText()); // better than nothing if the provider doesn't support AsTextIncludingElevationAndMeasure
+            }
+        }
+
+        public byte[] WellKnownBinary
+        {
+            get { return NullIfNotImplemented(geom => geom.AsBinary()); }
+        }
+
+        public string GmlString
+        {
+            get { return NullIfNotImplemented(geom => geom.AsGml()); }
+        }
+
+        public Exception NotSqlCompatible() { return EntityUtil.GeometryValueNotSqlCompatible(); }
+    }
+}