refactoring

Author: petesramek

PolylineAlgorithm.slnx

@@ -4,6 +4,7 @@
     <Project Path="benchmarks/PolylineAlgorithm.Comparison.Benchmarks/PolylineAlgorithm.Comparison.Benchmarks.csproj" />
   </Folder>
   <Folder Name="/src/">
+    <Project Path="src/PolylineAlgorithm.Abstraction/PolylineAlgorithm.Abstraction.csproj" Id="a39b8ed4-13da-4ef7-b144-68f0c281474f" />
     <Project Path="src/PolylineAlgorithm/PolylineAlgorithm.csproj" />
   </Folder>
   <Folder Name="/tests/">

benchmarks/PolylineAlgorithm.Benchmarks/PolylineBuilderBenchmark.cs

@@ -7,8 +7,10 @@ namespace PolylineAlgorithm.Benchmarks;
 
 using BenchmarkDotNet.Attributes;
 using PolylineAlgorithm;
+using PolylineAlgorithm.Abstraction.Internal;
 using PolylineAlgorithm.Internal;
 using PolylineAlgorithm.Utility;
+using System.Buffers;
 
 /// <summary>
 /// Benchmarks for the <see cref="PolylineValue"/> struct.
@@ -46,7 +48,7 @@ public void SetupData() {
     /// </summary>
     /// <returns>The encoded polyline.</returns>
     [Benchmark]
-    public Polyline PolylineBuilder_Append_Memory() {
+    public ReadOnlySequence<char> PolylineBuilder_Append_Memory() {
         for (int i = 0; i < SegmentsCount; i++) {
             Builder
                 .Append(MemoryValue);

benchmarks/PolylineAlgorithm.Benchmarks/PolylineEncoderBenchmark.cs

@@ -7,6 +7,7 @@ namespace PolylineAlgorithm.Benchmarks;
 
 using BenchmarkDotNet.Attributes;
 using PolylineAlgorithm;
+using PolylineAlgorithm.Abstraction;
 using PolylineAlgorithm.Utility;
 using System.Collections.Generic;
 

src/PolylineAlgorithm/Abstraction/IPolylineDecoder.cs renamed to src/PolylineAlgorithm.Abstraction/IPolylineDecoder.cs

@@ -10,7 +10,7 @@ namespace PolylineAlgorithm.Abstraction;
 /// <summary>
 /// Defines a contract for decoding an encoded polyline into a collection of geographic coordinates.
 /// </summary>
-public interface IPolylineDecoder {
+public interface IPolylineDecoder<TCoordinate, TPolyline> {
     /// <summary>
     /// Decodes the specified encoded polyline into a sequence of geographic coordinates.
     /// </summary>
@@ -20,5 +20,5 @@ public interface IPolylineDecoder {
     /// <returns>
     /// An <see cref="IEnumerable{T}"/> of <see cref="Coordinate"/> representing the decoded latitude and longitude pairs.
     /// </returns>
-    IEnumerable<Coordinate> Decode(Polyline polyline);
+    IEnumerable<TCoordinate> Decode(TPolyline coordinates);
 }

src/PolylineAlgorithm/Abstraction/IPolylineEncoder.cs renamed to src/PolylineAlgorithm.Abstraction/IPolylineEncoder.cs

@@ -10,7 +10,7 @@ namespace PolylineAlgorithm.Abstraction;
 /// <summary>
 /// Defines a contract for encoding a collection of geographic coordinates into an encoded polyline string.
 /// </summary>
-public interface IPolylineEncoder {
+public interface IPolylineEncoder<TCoordinate, TPolyline> {
     /// <summary>
     /// Encodes a sequence of geographic coordinates into an encoded polyline representation.
     /// </summary>
@@ -20,5 +20,5 @@ public interface IPolylineEncoder {
     /// <returns>
     /// A <see cref="Polyline"/> containing the encoded polyline string that represents the input coordinates.
     /// </returns>
-    Polyline Encode(IEnumerable<Coordinate> coordinates);
+    TPolyline Encode(IEnumerable<TCoordinate> coordinates);
 }

src/PolylineAlgorithm/Internal/CoordinateVariance.cs renamed to src/PolylineAlgorithm.Abstraction/Internal/CoordinateVariance.cs

@@ -3,7 +3,7 @@
 // Licensed under the MIT License. See LICENSE file in the project root for full license information.
 //
 
-namespace PolylineAlgorithm.Internal;
+namespace PolylineAlgorithm.Abstraction.Internal;
 
 using System;
 using System.Diagnostics;

src/PolylineAlgorithm.Abstraction/Internal/Defaults.cs

@@ -0,0 +1,64 @@
+//
+// Copyright © Pete Sramek. All rights reserved.
+// Licensed under the MIT License. See LICENSE file in the project root for full license information.
+//
+
+namespace PolylineAlgorithm.Abstraction.Internal;
+using System.Diagnostics.CodeAnalysis;
+
+/// <summary>
+/// Provides default values and constants used throughout the Polyline Algorithm.
+/// Organizes defaults for algorithm parameters, polyline encoding, and geographic coordinates into nested static classes.
+/// </summary>
+[ExcludeFromCodeCoverage]
+internal static class Defaults {
+    /// <summary>
+    /// Contains default values and constants specific to the polyline encoding algorithm.
+    /// </summary>
+    public static class Algorithm {
+        /// <summary>
+        /// The precision factor used to round coordinate values during polyline encoding.
+        /// </summary>
+        public const int Precision = 100_000;
+
+        /// <summary>
+        /// The number of bits to shift during polyline encoding.
+        /// </summary>
+        public const byte ShiftLength = 5;
+
+        /// <summary>
+        /// The ASCII value for the question mark character ('?').
+        /// </summary>
+        public const byte QuestionMark = 63;
+
+        /// <summary>
+        /// The ASCII value for the space character (' ').
+        /// </summary>
+        public const byte Space = 32;
+
+        /// <summary>
+        /// The ASCII value for the unit separator character.
+        /// </summary>
+        public const byte UnitSeparator = 31;
+    }
+
+    /// <summary>
+    /// Contains default values and constants related to polyline encoding.
+    /// </summary>
+    public static class Polyline {
+        /// <summary>
+        /// An array of delimiter byte values used in polyline encoding, derived by adding the ASCII value of the question mark ('?') to a range of integers.
+        /// </summary>
+        public static readonly byte[] Delimiters = [.. Enumerable.Range(0, 32).Select(n => (byte)(n + Algorithm.QuestionMark))];
+
+        /// <summary>
+        /// The minimum number of characters required to represent an encoded coordinate.
+        /// </summary>
+        public const int MinEncodedCoordinateLength = 2;
+
+        /// <summary>
+        /// The maximum number of characters allowed to represent an encoded coordinate.
+        /// </summary>
+        public const int MaxEncodedCoordinateLength = 12;
+    }
+}

src/PolylineAlgorithm/Internal/PolylineBuilder.cs renamed to src/PolylineAlgorithm.Abstraction/Internal/PolylineBuilder.cs

@@ -3,9 +3,10 @@
 // Licensed under the MIT License. See LICENSE file in the project root for full license information.
 //
 
-namespace PolylineAlgorithm.Internal;
+namespace PolylineAlgorithm.Abstraction.Internal;
 
 using System;
+using System.Buffers;
 using System.Runtime.InteropServices;
 
 /// <summary>
@@ -42,11 +43,11 @@ public void Append(ReadOnlyMemory<char> value) {
     /// A <see cref="Polyline"/> representing the combined character segments.
     /// If no segments have been appended, returns an empty <see cref="Polyline"/>.
     /// </returns>
-    public readonly Polyline Build() {
+    public readonly ReadOnlySequence<char> Build() {
         if (_initial is null) {
-            return Polyline.FromMemory(ReadOnlyMemory<char>.Empty);
+            return new();
         }
 
-        return Polyline.FromSequence(new(_initial, 0, _last, _last!.Memory.Length));
+        return new(_initial, 0, _last, _last!.Memory.Length);
     }
 }

src/PolylineAlgorithm/Internal/PolylineSegment.cs renamed to src/PolylineAlgorithm.Abstraction/Internal/PolylineSegment.cs

@@ -3,7 +3,7 @@
 // Licensed under the MIT License. See LICENSE file in the project root for full license information.
 //
 
-namespace PolylineAlgorithm.Internal;
+namespace PolylineAlgorithm.Abstraction.Internal;
 
 using System.Buffers;
 

src/PolylineAlgorithm/InvalidPolylineException.cs renamed to src/PolylineAlgorithm.Abstraction/InvalidPolylineException.cs

@@ -3,9 +3,9 @@
 // Licensed under the MIT License. See LICENSE file in the project root for full license information.
 //
 
-namespace PolylineAlgorithm;
+namespace PolylineAlgorithm.Abstraction;
 
-using PolylineAlgorithm.Properties;
+using PolylineAlgorithm.Abstraction.Properties;
 using System;
 using System.Diagnostics;
 using System.Diagnostics.CodeAnalysis;