bepin/BepInEx.Core/SemVersion.cs

// Backported to net35 from https://github.com/maxhauser/semver

using System;
using System.Globalization;
using System.Runtime.Serialization;
using System.Security.Permissions;
using System.Text;
using System.Text.RegularExpressions;

namespace BepInEx.Core
{
	internal static class IntExtensions
	{
		/// <summary>
		/// The number of digits in a non-negative number. Returns 1 for all
		/// negative numbers. That is ok because we are using it to calculate
		/// string length for a <see cref="StringBuilder"/> for numbers that
		/// aren't supposed to be negative, but when they are it is just a little
		/// slower.
		/// </summary>
		/// <remarks>
		/// This approach is based on https://stackoverflow.com/a/51099524/268898
		/// where the poster offers performance benchmarks showing this is the
		/// fastest way to get a number of digits.
		/// </remarks>
		public static int Digits(this int n)
		{
			if (n < 10)
				return 1;
			if (n < 100)
				return 2;
			if (n < 1_000)
				return 3;
			if (n < 10_000)
				return 4;
			if (n < 100_000)
				return 5;
			if (n < 1_000_000)
				return 6;
			if (n < 10_000_000)
				return 7;
			if (n < 100_000_000)
				return 8;
			if (n < 1_000_000_000)
				return 9;
			return 10;
		}
	}

	[Serializable]
	public sealed class SemVersion : IComparable<SemVersion>, IComparable, ISerializable
	{
		private static readonly Regex ParseEx =
			new Regex(@"^(?<major>\d+)" +
					  @"(?>\.(?<minor>\d+))?" +
					  @"(?>\.(?<patch>\d+))?" +
					  @"(?>\-(?<pre>[0-9A-Za-z\-\.]+))?" +
					  @"(?>\+(?<build>[0-9A-Za-z\-\.]+))?$",
				RegexOptions.CultureInvariant | RegexOptions.Compiled | RegexOptions.ExplicitCapture,
				TimeSpan.FromSeconds(0.5));

#pragma warning disable CA1801 // Parameter unused
		/// <summary>
		/// Deserialize a <see cref="SemVersion"/>.
		/// </summary>
		/// <exception cref="ArgumentNullException">The <paramref name="info"/> parameter is null.</exception>
		private SemVersion(SerializationInfo info, StreamingContext context)
#pragma warning restore CA1801 // Parameter unused
		{
			if (info == null)
				throw new ArgumentNullException(nameof(info));
			var semVersion = Parse(info.GetString("SemVersion"));
			Major = semVersion.Major;
			Minor = semVersion.Minor;
			Patch = semVersion.Patch;
			Prerelease = semVersion.Prerelease;
			Build = semVersion.Build;
		}

		/// <summary>
		/// Constructs a new instance of the <see cref="SemVersion" /> class.
		/// </summary>
		/// <param name="major">The major version.</param>
		/// <param name="minor">The minor version.</param>
		/// <param name="patch">The patch version.</param>
		/// <param name="prerelease">The prerelease version (e.g. "alpha").</param>
		/// <param name="build">The build metadata (e.g. "nightly.232").</param>
		public SemVersion(int major, int minor = 0, int patch = 0, string prerelease = "", string build = "")
		{
			Major = major;
			Minor = minor;
			Patch = patch;

			Prerelease = prerelease ?? "";
			Build = build ?? "";
		}

		/// <summary>
		/// Constructs a new instance of the <see cref="SemVersion"/> class from
		/// a <see cref="System.Version"/>.
		/// </summary>
		/// <param name="version">The <see cref="Version"/> that is used to initialize
		/// the Major, Minor, Patch and Build.</param>
		/// <returns>A <see cref="SemVersion"/> with the same Major and Minor version.
		/// The Patch version will be the fourth part of the version number. The
		/// build meta data will contain the third part of the version number if
		/// it is greater than zero.</returns>
		public SemVersion(Version version)
		{
			if (version == null)
				throw new ArgumentNullException(nameof(version));

			Major = version.Major;
			Minor = version.Minor;

			if (version.Revision >= 0)
				Patch = version.Revision;

			Prerelease = "";

			Build = version.Build > 0 ? version.Build.ToString(CultureInfo.InvariantCulture) : "";
		}

		/// <summary>
		/// Converts the string representation of a semantic version to its <see cref="SemVersion"/> equivalent.
		/// </summary>
		/// <param name="version">The version string.</param>
		/// <param name="strict">If set to <see langword="true"/> minor and patch version are required,
		/// otherwise they are optional.</param>
		/// <returns>The <see cref="SemVersion"/> object.</returns>
		/// <exception cref="ArgumentNullException">The <paramref name="version"/> is <see langword="null"/>.</exception>
		/// <exception cref="ArgumentException">The <paramref name="version"/> has an invalid format.</exception>
		/// <exception cref="InvalidOperationException">The <paramref name="version"/> is missing Minor or Patch versions and <paramref name="strict"/> is <see langword="true"/>.</exception>
		/// <exception cref="OverflowException">The Major, Minor, or Patch versions are larger than <code>int.MaxValue</code>.</exception>
		public static SemVersion Parse(string version, bool strict = false)
		{
			var match = ParseEx.Match(version);
			if (!match.Success)
				throw new ArgumentException($"Invalid version '{version}'.", nameof(version));

			var major = int.Parse(match.Groups["major"].Value, CultureInfo.InvariantCulture);

			var minorMatch = match.Groups["minor"];
			int minor = 0;
			if (minorMatch.Success)
				minor = int.Parse(minorMatch.Value, CultureInfo.InvariantCulture);
			else if (strict)
				throw new InvalidOperationException("Invalid version (no minor version given in strict mode)");

			var patchMatch = match.Groups["patch"];
			int patch = 0;
			if (patchMatch.Success)
				patch = int.Parse(patchMatch.Value, CultureInfo.InvariantCulture);
			else if (strict)
				throw new InvalidOperationException("Invalid version (no patch version given in strict mode)");

			var prerelease = match.Groups["pre"].Value;
			var build = match.Groups["build"].Value;

			return new SemVersion(major, minor, patch, prerelease, build);
		}

		/// <summary>
		/// Converts the string representation of a semantic version to its <see cref="SemVersion"/>
		/// equivalent and returns a value that indicates whether the conversion succeeded.
		/// </summary>
		/// <param name="version">The version string.</param>
		/// <param name="semver">When the method returns, contains a <see cref="SemVersion"/> instance equivalent
		/// to the version string passed in, if the version string was valid, or <see langword="null"/> if the
		/// version string was not valid.</param>
		/// <param name="strict">If set to <see langword="true"/> minor and patch version are required,
		/// otherwise they are optional.</param>
		/// <returns><see langword="false"/> when a invalid version string is passed, otherwise <see langword="true"/>.</returns>
		public static bool TryParse(string version, out SemVersion semver, bool strict = false)
		{
			semver = null;
			if (version is null)
				return false;

			var match = ParseEx.Match(version);
			if (!match.Success)
				return false;

			if (!int.TryParse(match.Groups["major"].Value, NumberStyles.Integer, CultureInfo.InvariantCulture, out var major))
				return false;

			var minorMatch = match.Groups["minor"];
			int minor = 0;
			if (minorMatch.Success)
			{
				if (!int.TryParse(minorMatch.Value, NumberStyles.Integer, CultureInfo.InvariantCulture, out minor))
					return false;
			}
			else if (strict)
				return false;

			var patchMatch = match.Groups["patch"];
			int patch = 0;
			if (patchMatch.Success)
			{
				if (!int.TryParse(patchMatch.Value, NumberStyles.Integer, CultureInfo.InvariantCulture, out patch))
					return false;
			}
			else if (strict)
				return false;

			var prerelease = match.Groups["pre"].Value;
			var build = match.Groups["build"].Value;

			semver = new SemVersion(major, minor, patch, prerelease, build);
			return true;
		}

		/// <summary>
		/// Checks whether two semantic versions are equal.
		/// </summary>
		/// <param name="versionA">The first version to compare.</param>
		/// <param name="versionB">The second version to compare.</param>
		/// <returns><see langword="true"/> if the two values are equal, otherwise <see langword="false"/>.</returns>
		public static bool Equals(SemVersion versionA, SemVersion versionB)
		{
			if (ReferenceEquals(versionA, versionB))
				return true;
			if (versionA is null || versionB is null)
				return false;
			return versionA.Equals(versionB);
		}

		/// <summary>
		/// Compares the specified versions.
		/// </summary>
		/// <param name="versionA">The first version to compare.</param>
		/// <param name="versionB">The second version to compare.</param>
		/// <returns>A signed number indicating the relative values of <paramref name="versionA"/> and <paramref name="versionB"/>.</returns>
		public static int Compare(SemVersion versionA, SemVersion versionB)
		{
			if (ReferenceEquals(versionA, versionB))
				return 0;
			if (versionA is null)
				return -1;
			if (versionB is null)
				return 1;
			return versionA.CompareTo(versionB);
		}

		/// <summary>
		/// Make a copy of the current instance with changed properties.
		/// </summary>
		/// <param name="major">The value to replace the major version or <see langword="null"/> to leave it unchanged.</param>
		/// <param name="minor">The value to replace the minor version or <see langword="null"/> to leave it unchanged.</param>
		/// <param name="patch">The value to replace the patch version or <see langword="null"/> to leave it unchanged.</param>
		/// <param name="prerelease">The value to replace the prerelease version or <see langword="null"/> to leave it unchanged.</param>
		/// <param name="build">The value to replace the build metadata or <see langword="null"/> to leave it unchanged.</param>
		/// <returns>The new version object.</returns>
		/// <remarks>
		/// The change method is intended to be called using named argument syntax, passing only
		/// those fields to be changed.
		/// </remarks>
		/// <example>
		/// To change only the patch version:
		/// <code>version.Change(patch: 4)</code>
		/// </example>
		public SemVersion Change(int? major = null, int? minor = null, int? patch = null,
			string prerelease = null, string build = null)
		{
			return new SemVersion(
				major ?? Major,
				minor ?? Minor,
				patch ?? Patch,
				prerelease ?? Prerelease,
				build ?? Build);
		}

		/// <summary>
		/// Gets the major version.
		/// </summary>
		/// <value>
		/// The major version.
		/// </value>
		public int Major { get; }

		/// <summary>
		/// Gets the minor version.
		/// </summary>
		/// <value>
		/// The minor version.
		/// </value>
		public int Minor { get; }

		/// <summary>
		/// Gets the patch version.
		/// </summary>
		/// <value>
		/// The patch version.
		/// </value>
		public int Patch { get; }

		/// <summary>
		/// Gets the prerelease version.
		/// </summary>
		/// <value>
		/// The prerelease version. Empty string if this is a release version.
		/// </value>
		public string Prerelease { get; }

		/// <summary>
		/// Gets the build metadata.
		/// </summary>
		/// <value>
		/// The build metadata. Empty string if there is no build metadata.
		/// </value>
		public string Build { get; }

		/// <summary>
		/// Returns the <see cref="string" /> equivalent of this version.
		/// </summary>
		/// <returns>
		/// The <see cref="string" /> equivalent of this version.
		/// </returns>
		public override string ToString()
		{
			// Assume all separators ("..-+"), at most 2 extra chars
			var estimatedLength = 4 + Major.Digits() + Minor.Digits() + Patch.Digits()
								  + Prerelease.Length + Build.Length;
			var version = new StringBuilder(estimatedLength);
			version.Append(Major);
			version.Append('.');
			version.Append(Minor);
			version.Append('.');
			version.Append(Patch);
			if (Prerelease.Length > 0)
			{
				version.Append('-');
				version.Append(Prerelease);
			}

			if (Build.Length > 0)
			{
				version.Append('+');
				version.Append(Build);
			}

			return version.ToString();
		}

		/// <summary>
		/// Compares the current instance with another object of the same type and returns an integer that indicates
		/// whether the current instance precedes, follows, or occurs in the same position in the sort order as the
		/// other object.
		/// </summary>
		/// <param name="obj">An object to compare with this instance.</param>
		/// <returns>
		/// A value that indicates the relative order of the objects being compared.
		/// The return value has these meanings:
		///  Less than zero: This instance precedes <paramref name="obj" /> in the sort order.
		///  Zero: This instance occurs in the same position in the sort order as <paramref name="obj" />.
		///  Greater than zero: This instance follows <paramref name="obj" /> in the sort order.
		/// </returns>
		/// <exception cref="InvalidCastException">The <paramref name="obj"/> is not a <see cref="SemVersion"/>.</exception>
		public int CompareTo(object obj)
		{
			return CompareTo((SemVersion)obj);
		}

		/// <summary>
		/// Compares the current instance with another object of the same type and returns an integer that indicates
		/// whether the current instance precedes, follows, or occurs in the same position in the sort order as the
		/// other object.
		/// </summary>
		/// <param name="other">An object to compare with this instance.</param>
		/// <returns>
		/// A value that indicates the relative order of the objects being compared.
		/// The return value has these meanings:
		///  Less than zero: This instance precedes <paramref name="other" /> in the sort order.
		///  Zero: This instance occurs in the same position in the sort order as <paramref name="other" />.
		///  Greater than zero: This instance follows <paramref name="other" /> in the sort order.
		/// </returns>
		public int CompareTo(SemVersion other)
		{
			var r = CompareByPrecedence(other);
			if (r != 0)
				return r;

#pragma warning disable CA1062 // Validate arguments of public methods
			// If other is null, CompareByPrecedence() returns 1
			return CompareComponent(Build, other.Build);
#pragma warning restore CA1062 // Validate arguments of public methods
		}

		/// <summary>
		/// Returns whether two semantic versions have the same precedence. Versions
		/// that differ only by build metadata have the same precedence.
		/// </summary>
		/// <param name="other">The semantic version to compare to.</param>
		/// <returns><see langword="true"/> if the version precedences are equal.</returns>
		public bool PrecedenceMatches(SemVersion other)
		{
			return CompareByPrecedence(other) == 0;
		}

		/// <summary>
		/// Compares two semantic versions by precedence as defined in the SemVer spec. Versions
		/// that differ only by build metadata have the same precedence.
		/// </summary>
		/// <param name="other">The semantic version.</param>
		/// <returns>
		/// A value that indicates the relative order of the objects being compared.
		/// The return value has these meanings:
		///  Less than zero: This instance precedes <paramref name="other" /> in the sort order.
		///  Zero: This instance occurs in the same position in the sort order as <paramref name="other" />.
		///  Greater than zero: This instance follows <paramref name="other" /> in the sort order.
		/// </returns>
		public int CompareByPrecedence(SemVersion other)
		{
			if (other is null)
				return 1;

			var r = Major.CompareTo(other.Major);
			if (r != 0)
				return r;

			r = Minor.CompareTo(other.Minor);
			if (r != 0)
				return r;

			r = Patch.CompareTo(other.Patch);
			if (r != 0)
				return r;

			return CompareComponent(Prerelease, other.Prerelease, true);
		}

		private static int CompareComponent(string a, string b, bool nonemptyIsLower = false)
		{
			var aEmpty = string.IsNullOrEmpty(a);
			var bEmpty = string.IsNullOrEmpty(b);
			if (aEmpty && bEmpty)
				return 0;

			if (aEmpty)
				return nonemptyIsLower ? 1 : -1;
			if (bEmpty)
				return nonemptyIsLower ? -1 : 1;

			var aComps = a.Split('.');
			var bComps = b.Split('.');

			var minLen = Math.Min(aComps.Length, bComps.Length);
			for (int i = 0; i < minLen; i++)
			{
				var ac = aComps[i];
				var bc = bComps[i];
				var aIsNum = int.TryParse(ac, out var aNum);
				var bIsNum = int.TryParse(bc, out var bNum);
				int r;
				if (aIsNum && bIsNum)
				{
					r = aNum.CompareTo(bNum);
					if (r != 0)
						return r;
				}
				else
				{
					if (aIsNum)
						return -1;
					if (bIsNum)
						return 1;
					r = string.CompareOrdinal(ac, bc);
					if (r != 0)
						return r;
				}
			}

			return aComps.Length.CompareTo(bComps.Length);
		}

		/// <summary>
		/// Determines whether the specified <see cref="object" /> is equal to this instance.
		/// </summary>
		/// <param name="obj">The <see cref="object" /> to compare with this instance.</param>
		/// <returns>
		///   <see langword="true"/> if the specified <see cref="object" /> is equal to this instance, otherwise <see langword="false"/>.
		/// </returns>
		/// <exception cref="InvalidCastException">The <paramref name="obj"/> is not a <see cref="SemVersion"/>.</exception>
		public override bool Equals(object obj)
		{
			if (obj is null)
				return false;

			if (ReferenceEquals(this, obj))
				return true;

			var other = (SemVersion)obj;

			return Major == other.Major
				   && Minor == other.Minor
				   && Patch == other.Patch
				   && string.Equals(Prerelease, other.Prerelease, StringComparison.Ordinal)
				   && string.Equals(Build, other.Build, StringComparison.Ordinal);
		}

		/// <summary>
		/// Returns a hash code for this instance.
		/// </summary>
		/// <returns>
		/// A hash code for this instance, suitable for use in hashing algorithms and data structures like a hash table.
		/// </returns>
		public override int GetHashCode()
		{
			unchecked
			{
				// TODO verify this. Some versions start result = 17. Some use 37 instead of 31
				int result = Major.GetHashCode();
				result = result * 31 + Minor.GetHashCode();
				result = result * 31 + Patch.GetHashCode();
				result = result * 31 + Prerelease.GetHashCode();
				result = result * 31 + Build.GetHashCode();
				return result;
			}
		}

		/// <summary>
		/// Populates a <see cref="SerializationInfo"/> with the data needed to serialize the target object.
		/// </summary>
		/// <param name="info">The <see cref="SerializationInfo"/> to populate with data.</param>
		/// <param name="context">The destination (see <see cref="SerializationInfo"/>) for this serialization.</param>
		[SecurityPermission(SecurityAction.Demand, SerializationFormatter = true)]
		public void GetObjectData(SerializationInfo info, StreamingContext context)
		{
			if (info == null)
				throw new ArgumentNullException(nameof(info));
			info.AddValue("SemVersion", ToString());
		}

#pragma warning disable CA2225 // Operator overloads have named alternates
		/// <summary>
		/// Implicit conversion from <see cref="string"/> to <see cref="SemVersion"/>.
		/// </summary>
		/// <param name="version">The semantic version.</param>
		/// <returns>The <see cref="SemVersion"/> object.</returns>
		/// <exception cref="ArgumentNullException">The <paramref name="version"/> is <see langword="null"/>.</exception>
		/// <exception cref="ArgumentException">The version number has an invalid format.</exception>
		/// <exception cref="OverflowException">The Major, Minor, or Patch versions are larger than <code>int.MaxValue</code>.</exception>
		public static implicit operator SemVersion(string version)
#pragma warning restore CA2225 // Operator overloads have named alternates
		{
			return Parse(version);
		}

		/// <summary>
		/// Compares two semantic versions for equality.
		/// </summary>
		/// <param name="left">The left value.</param>
		/// <param name="right">The right value.</param>
		/// <returns>If left is equal to right <see langword="true"/>, otherwise <see langword="false"/>.</returns>
		public static bool operator ==(SemVersion left, SemVersion right)
		{
			return Equals(left, right);
		}

		/// <summary>
		/// Compares two semantic versions for inequality.
		/// </summary>
		/// <param name="left">The left value.</param>
		/// <param name="right">The right value.</param>
		/// <returns>If left is not equal to right <see langword="true"/>, otherwise <see langword="false"/>.</returns>
		public static bool operator !=(SemVersion left, SemVersion right)
		{
			return !Equals(left, right);
		}

		/// <summary>
		/// Compares two semantic versions.
		/// </summary>
		/// <param name="left">The left value.</param>
		/// <param name="right">The right value.</param>
		/// <returns>If left is greater than right <see langword="true"/>, otherwise <see langword="false"/>.</returns>
		public static bool operator >(SemVersion left, SemVersion right)
		{
			return Compare(left, right) > 0;
		}

		/// <summary>
		/// Compares two semantic versions.
		/// </summary>
		/// <param name="left">The left value.</param>
		/// <param name="right">The right value.</param>
		/// <returns>If left is greater than or equal to right <see langword="true"/>, otherwise <see langword="false"/>.</returns>
		public static bool operator >=(SemVersion left, SemVersion right)
		{
			return Equals(left, right) || Compare(left, right) > 0;
		}

		/// <summary>
		/// Compares two semantic versions.
		/// </summary>
		/// <param name="left">The left value.</param>
		/// <param name="right">The right value.</param>
		/// <returns>If left is less than right <see langword="true"/>, otherwise <see langword="false"/>.</returns>
		public static bool operator <(SemVersion left, SemVersion right)
		{
			return Compare(left, right) < 0;
		}

		/// <summary>
		/// Compares two semantic versions.
		/// </summary>
		/// <param name="left">The left value.</param>
		/// <param name="right">The right value.</param>
		/// <returns>If left is less than or equal to right <see langword="true"/>, otherwise <see langword="false"/>.</returns>
		public static bool operator <=(SemVersion left, SemVersion right)
		{
			return Equals(left, right) || Compare(left, right) < 0;
		}
	}
}