Initial commit

12 files changed, 564 insertions, 0 deletions

diff --git a/src/IOL.Helpers.sln b/src/IOL.Helpers.sln
new file mode 100644
index 0000000..b166d6e
--- /dev/null
+++ b/src/IOL.Helpers.sln
@@ -0,0 +1,34 @@
+
+Microsoft Visual Studio Solution File, Format Version 12.00
+# Visual Studio Version 16
+VisualStudioVersion = 16.6.30114.105
+MinimumVisualStudioVersion = 10.0.40219.1
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "IOL.Helpers", "IOL.Helpers\IOL.Helpers.csproj", "{DE4D43B0-FBE6-40B7-9C8F-FFFA7987F87B}"
+EndProject
+Global
+	GlobalSection(SolutionConfigurationPlatforms) = preSolution
+		Debug|Any CPU = Debug|Any CPU
+		Debug|x64 = Debug|x64
+		Debug|x86 = Debug|x86
+		Release|Any CPU = Release|Any CPU
+		Release|x64 = Release|x64
+		Release|x86 = Release|x86
+	EndGlobalSection
+	GlobalSection(SolutionProperties) = preSolution
+		HideSolutionNode = FALSE
+	EndGlobalSection
+	GlobalSection(ProjectConfigurationPlatforms) = postSolution
+		{DE4D43B0-FBE6-40B7-9C8F-FFFA7987F87B}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{DE4D43B0-FBE6-40B7-9C8F-FFFA7987F87B}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{DE4D43B0-FBE6-40B7-9C8F-FFFA7987F87B}.Debug|x64.ActiveCfg = Debug|Any CPU
+		{DE4D43B0-FBE6-40B7-9C8F-FFFA7987F87B}.Debug|x64.Build.0 = Debug|Any CPU
+		{DE4D43B0-FBE6-40B7-9C8F-FFFA7987F87B}.Debug|x86.ActiveCfg = Debug|Any CPU
+		{DE4D43B0-FBE6-40B7-9C8F-FFFA7987F87B}.Debug|x86.Build.0 = Debug|Any CPU
+		{DE4D43B0-FBE6-40B7-9C8F-FFFA7987F87B}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{DE4D43B0-FBE6-40B7-9C8F-FFFA7987F87B}.Release|Any CPU.Build.0 = Release|Any CPU
+		{DE4D43B0-FBE6-40B7-9C8F-FFFA7987F87B}.Release|x64.ActiveCfg = Release|Any CPU
+		{DE4D43B0-FBE6-40B7-9C8F-FFFA7987F87B}.Release|x64.Build.0 = Release|Any CPU
+		{DE4D43B0-FBE6-40B7-9C8F-FFFA7987F87B}.Release|x86.ActiveCfg = Release|Any CPU
+		{DE4D43B0-FBE6-40B7-9C8F-FFFA7987F87B}.Release|x86.Build.0 = Release|Any CPU
+	EndGlobalSection
+EndGlobal
diff --git a/src/IOL.Helpers/CryptographyHelpers.cs b/src/IOL.Helpers/CryptographyHelpers.cs
new file mode 100644
index 0000000..6ea18b6
--- /dev/null
+++ b/src/IOL.Helpers/CryptographyHelpers.cs
@@ -0,0 +1,173 @@
+using System;
+using System.Linq;
+using System.Security.Cryptography;
+using System.Text;
+
+namespace IOL.Helpers
+{
+	public static class CryptographyHelpers
+	{
+		// https://github.com/DuendeSoftware/IdentityServer/blob/main/src/IdentityServer/Extensions/HashExtensions.cs
+
+		private const int AES_BLOCK_BYTE_SIZE = 128 / 8;
+		private static readonly RandomNumberGenerator _random = RandomNumberGenerator.Create();
+
+		/// <summary>
+		/// Creates a MD5 hash of the specified input.
+		/// </summary>
+		/// <returns>A hash</returns>
+		public static string Md5(this string input, string salt = default) {
+			if (input.IsNullOrWhiteSpace()) return string.Empty;
+
+			var hmacMd5 = salt.HasValue() ? new HMACMD5(Encoding.UTF8.GetBytes(salt ?? "")) : new HMACMD5();
+			var saltedHash = hmacMd5.ComputeHash(Encoding.UTF8.GetBytes(input));
+			return Convert.ToBase64String(saltedHash);
+		}
+
+
+		/// <summary>
+		/// Method to perform a very simple (and classical) encryption for a string. This is NOT at 
+		/// all secure, it is only intended to make the string value non-obvious at a first glance.
+		///
+		/// The shiftOrUnshift argument is an arbitrary "key value", and must be a non-zero integer 
+		/// between -65535 and 65535 (inclusive). To decrypt the encrypted string you use the negative 
+		/// value. For example, if you encrypt with -42, then you decrypt with +42, or vice-versa.
+		///
+		/// This is inspired by, and largely based on, this:
+		/// https://stackoverflow.com/a/13026595/253938
+		/// </summary>
+		/// <param name="inputString">string to be encrypted or decrypted, must not be null</param>
+		/// <param name="shiftOrUnshift">see above</param>
+		/// <returns>encrypted or decrypted string</returns>
+		public static string CaesarCipher(string inputString, int shiftOrUnshift) {
+			const int C64_K = ushort.MaxValue + 1;
+			if (inputString == null) throw new ArgumentException("Must not be null.", nameof(inputString));
+			switch (shiftOrUnshift) {
+				case 0: throw new ArgumentException("Must not be zero.", nameof(shiftOrUnshift));
+				case <= -C64_K:
+				case >= C64_K: throw new ArgumentException("Out of range.", nameof(shiftOrUnshift));
+			}
+
+			// Perform the Caesar cipher shifting, using modulo operator to provide wrap-around
+			var charArray = new char[inputString.Length];
+			for (var i = 0; i < inputString.Length; i++) {
+				charArray[i] =
+					Convert.ToChar((Convert.ToInt32(inputString[i]) + shiftOrUnshift + C64_K) % C64_K);
+			}
+
+			return new string(charArray);
+		}
+
+		//https://tomrucki.com/posts/aes-encryption-in-csharp/
+		public static string EncryptWithAes(this string toEncrypt, string password) {
+			var key = GetKey(password);
+
+			using var aes = CreateAes();
+			var iv = GenerateRandomBytes(AES_BLOCK_BYTE_SIZE);
+			var plainText = Encoding.UTF8.GetBytes(toEncrypt);
+
+			using var encryptor = aes.CreateEncryptor(key, iv);
+			var cipherText = encryptor
+				.TransformFinalBlock(plainText, 0, plainText.Length);
+
+			var result = new byte[iv.Length + cipherText.Length];
+			iv.CopyTo(result, 0);
+			cipherText.CopyTo(result, iv.Length);
+
+			return Convert.ToBase64String(result);
+		}
+
+		private static Aes CreateAes() {
+			var aes = Aes.Create();
+			aes.Mode = CipherMode.CBC;
+			aes.Padding = PaddingMode.PKCS7;
+			return aes;
+		}
+
+		public static string DecryptWithAes(this string input, string password) {
+			var key = GetKey(password);
+			var encryptedData = Convert.FromBase64String(input);
+
+			using var aes = CreateAes();
+			var iv = encryptedData.Take(AES_BLOCK_BYTE_SIZE).ToArray();
+			var cipherText = encryptedData.Skip(AES_BLOCK_BYTE_SIZE).ToArray();
+
+			using var decryptor = aes.CreateDecryptor(key, iv);
+			var decryptedBytes = decryptor
+				.TransformFinalBlock(cipherText, 0, cipherText.Length);
+			return Encoding.UTF8.GetString(decryptedBytes);
+		}
+
+		private static byte[] GetKey(string password) {
+			var keyBytes = Encoding.UTF8.GetBytes(password);
+			using var md5 = MD5.Create();
+			return md5.ComputeHash(keyBytes);
+		}
+
+		private static byte[] GenerateRandomBytes(int numberOfBytes) {
+			var randomBytes = new byte[numberOfBytes];
+			_random.GetBytes(randomBytes);
+			return randomBytes;
+		}
+
+
+		/// <summary>
+		/// Creates a SHA256 hash of the specified input.
+		/// </summary>
+		/// <param name="input">The input.</param>
+		/// <returns>A hash</returns>
+		public static string Sha256(this string input) {
+			if (input.IsNullOrWhiteSpace()) return string.Empty;
+
+			using var sha = SHA256.Create();
+			var bytes = Encoding.UTF8.GetBytes(input);
+			var hash = sha.ComputeHash(bytes);
+
+			return Convert.ToBase64String(hash);
+		}
+
+		/// <summary>
+		/// Creates a SHA256 hash of the specified input.
+		/// </summary>
+		/// <param name="input">The input.</param>
+		/// <returns>A hash.</returns>
+		public static byte[] Sha256(this byte[] input) {
+			if (input == null) {
+				return null;
+			}
+
+			using var sha = SHA256.Create();
+			return sha.ComputeHash(input);
+		}
+
+		/// <summary>
+		/// Creates a SHA512 hash of the specified input.
+		/// </summary>
+		/// <param name="input">The input.</param>
+		/// <returns>A hash</returns>
+		public static string Sha512(this string input) {
+			if (input.IsNullOrWhiteSpace()) return string.Empty;
+
+			using var sha = SHA512.Create();
+			var bytes = Encoding.UTF8.GetBytes(input);
+			var hash = sha.ComputeHash(bytes);
+
+			return Convert.ToBase64String(hash);
+		}
+
+
+		/// <summary>
+		/// Creates a SHA256 hash of the specified input.
+		/// </summary>
+		/// <param name="input">The input.</param>
+		/// <returns>A hash.</returns>
+		public static byte[] Sha512(this byte[] input) {
+			if (input == null) {
+				return null;
+			}
+
+			using var sha = SHA512.Create();
+			return sha.ComputeHash(input);
+		}
+	}
+}
\ No newline at end of file
diff --git a/src/IOL.Helpers/DateTimeHelpers.cs b/src/IOL.Helpers/DateTimeHelpers.cs
new file mode 100644
index 0000000..07e951e
--- /dev/null
+++ b/src/IOL.Helpers/DateTimeHelpers.cs
@@ -0,0 +1,22 @@
+using System;
+
+namespace IOL.Helpers
+{
+	public static class DateTimeHelpers
+	{
+		public static DateTime ToTimeZoneId(this DateTime value, string timeZoneId) {
+			try {
+				var cstZone = TimeZoneInfo.FindSystemTimeZoneById(timeZoneId);
+				return TimeZoneInfo.ConvertTimeFromUtc(value, cstZone);
+			} catch (TimeZoneNotFoundException) {
+				Console.WriteLine("The registry does not define the " + timeZoneId + " zone.");
+				return default;
+			} catch (InvalidTimeZoneException) {
+				Console.WriteLine("Registry data on the " + timeZoneId + " zone has been corrupted.");
+				return default;
+			}
+		}
+
+		public static DateTime ToOsloTimeZone(this DateTime value) => ToTimeZoneId(value, "Europe/Oslo");
+	}
+}
\ No newline at end of file
diff --git a/src/IOL.Helpers/DoubleHelpers.cs b/src/IOL.Helpers/DoubleHelpers.cs
new file mode 100644
index 0000000..91d88ee
--- /dev/null
+++ b/src/IOL.Helpers/DoubleHelpers.cs
@@ -0,0 +1,11 @@
+using System;
+
+namespace IOL.Helpers
+{
+	public static class DoubleHelpers
+	{
+		public static string ToStringWithFixedDecimalPoints(this double value) {
+			return $"{Math.Truncate(value * 10) / 10:0.0}";
+		}
+	}
+}
\ No newline at end of file
diff --git a/src/IOL.Helpers/EnumHelpers.cs b/src/IOL.Helpers/EnumHelpers.cs
new file mode 100644
index 0000000..b63e045
--- /dev/null
+++ b/src/IOL.Helpers/EnumHelpers.cs
@@ -0,0 +1,13 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+
+namespace IOL.Helpers
+{
+	public static class EnumHelpers
+	{
+		public static IEnumerable<T> GetValues<T>() {
+			return Enum.GetValues(typeof(T)).Cast<T>();
+		}
+	}
+}
\ No newline at end of file
diff --git a/src/IOL.Helpers/HttpRequestHelpers.cs b/src/IOL.Helpers/HttpRequestHelpers.cs
new file mode 100644
index 0000000..5a0e145
--- /dev/null
+++ b/src/IOL.Helpers/HttpRequestHelpers.cs
@@ -0,0 +1,18 @@
+using System;
+using Microsoft.AspNetCore.Http;
+
+namespace IOL.Helpers
+{
+	public static class HttpRequestHelpers
+	{
+		public static string GetAppHost(this HttpRequest request) {
+			var forwardedHostHeader = request.Headers["X-Forwarded-Host"].ToString();
+			var forwardedProtoHeader = request.Headers["X-Forwarded-Proto"].ToString();
+			if (forwardedHostHeader.HasValue()) {
+				return (forwardedProtoHeader ?? "https") + "://" + forwardedHostHeader;
+			}
+
+			return request.Scheme + "://" + request.Host;
+		}
+	}
+}
\ No newline at end of file
diff --git a/src/IOL.Helpers/IOL.Helpers.csproj b/src/IOL.Helpers/IOL.Helpers.csproj
new file mode 100644
index 0000000..2b2842a
--- /dev/null
+++ b/src/IOL.Helpers/IOL.Helpers.csproj
@@ -0,0 +1,12 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <TargetFramework>net5.0</TargetFramework>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <PackageReference Include="Microsoft.AspNetCore.Cryptography.KeyDerivation" Version="5.0.4" />
+    <PackageReference Include="Microsoft.AspNetCore.Http.Abstractions" Version="2.2.0" />
+  </ItemGroup>
+
+</Project>
diff --git a/src/IOL.Helpers/PasswordHelpers.cs b/src/IOL.Helpers/PasswordHelpers.cs
new file mode 100644
index 0000000..5b85219
--- /dev/null
+++ b/src/IOL.Helpers/PasswordHelpers.cs
@@ -0,0 +1,70 @@
+using System;
+using System.Collections.Generic;
+using System.Security.Cryptography;
+using Microsoft.AspNetCore.Cryptography.KeyDerivation;
+
+namespace IOL.Helpers
+{
+	public static class PasswordHelper
+	{
+		private const int ITERATION_COUNT = 10000;
+		private const int SALT_SIZE = 128 / 8;
+		private const KeyDerivationPrf PRF = KeyDerivationPrf.HMACSHA256;
+
+		public static string HashPassword(string value) {
+			using var rng = RandomNumberGenerator.Create();
+			var salt = new byte[SALT_SIZE];
+			rng.GetBytes(salt);
+			var subkey = KeyDerivation.Pbkdf2(value, salt, PRF, ITERATION_COUNT, 256 / 8);
+			var outputBytes = new byte[13 + salt.Length + subkey.Length];
+			WriteNetworkByteOrder(outputBytes, 1, (uint) PRF);
+			WriteNetworkByteOrder(outputBytes, 5, (uint) ITERATION_COUNT);
+			WriteNetworkByteOrder(outputBytes, 9, (uint) SALT_SIZE);
+			Buffer.BlockCopy(salt, 0, outputBytes, 13, salt.Length);
+			Buffer.BlockCopy(subkey, 0, outputBytes, 13 + SALT_SIZE, subkey.Length);
+			return Convert.ToBase64String(outputBytes);
+		}
+
+		public static bool Verify(string password, string hashedPassword) {
+			var decodedHashedPassword = Convert.FromBase64String(hashedPassword);
+			if (decodedHashedPassword.Length == 0) return false;
+			try {
+				// Read header information
+				var networkByteOrder = (KeyDerivationPrf) ReadNetworkByteOrder(decodedHashedPassword, 1);
+				var saltLength = (int) ReadNetworkByteOrder(decodedHashedPassword, 9);
+
+				// Read the salt: must be >= 128 bits
+				if (saltLength < SALT_SIZE) return false;
+				var salt = new byte[saltLength];
+				Buffer.BlockCopy(decodedHashedPassword, 13, salt, 0, salt.Length);
+
+				// Read the subkey (the rest of the payload): must be >= 128 bits
+				var subkeyLength = decodedHashedPassword.Length - 13 - salt.Length;
+				if (subkeyLength < SALT_SIZE) return false;
+				var expectedSubkey = new byte[subkeyLength];
+				Buffer.BlockCopy(decodedHashedPassword, 13 + salt.Length, expectedSubkey, 0, expectedSubkey.Length);
+
+				// Hash the incoming password and verify it
+				var actualSubkey =
+					KeyDerivation.Pbkdf2(password, salt, networkByteOrder, ITERATION_COUNT, subkeyLength);
+				return CryptographicOperations.FixedTimeEquals(actualSubkey, expectedSubkey);
+			} catch {
+				return false;
+			}
+		}
+
+		private static uint ReadNetworkByteOrder(IReadOnlyList<byte> buffer, int offset) {
+			return ((uint) buffer[offset + 0] << 24)
+			       | ((uint) buffer[offset + 1] << 16)
+			       | ((uint) buffer[offset + 2] << 8)
+			       | buffer[offset + 3];
+		}
+
+		private static void WriteNetworkByteOrder(IList<byte> buffer, int offset, uint value) {
+			buffer[offset + 0] = (byte) (value >> 24);
+			buffer[offset + 1] = (byte) (value >> 16);
+			buffer[offset + 2] = (byte) (value >> 8);
+			buffer[offset + 3] = (byte) (value >> 0);
+		}
+	}
+}
\ No newline at end of file
diff --git a/src/IOL.Helpers/RandomStringGenerator.cs b/src/IOL.Helpers/RandomStringGenerator.cs
new file mode 100644
index 0000000..0d691db
--- /dev/null
+++ b/src/IOL.Helpers/RandomStringGenerator.cs
@@ -0,0 +1,18 @@
+using System;
+using System.Linq;
+
+namespace IOL.Helpers
+{
+	public static class RandomString
+	{
+		private static readonly Random _random = new Random();
+
+		public static string Generate(int length, bool numeric = false) {
+			var chars = numeric switch {
+				false => "ABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789",
+				true => "0123456789"
+			};
+			return new string(Enumerable.Repeat(chars, length).Select(s => s[_random.Next(s.Length)]).ToArray());
+		}
+	}
+}
\ No newline at end of file
diff --git a/src/IOL.Helpers/SlugGenerator.cs b/src/IOL.Helpers/SlugGenerator.cs
new file mode 100644
index 0000000..3f53dd6
--- /dev/null
+++ b/src/IOL.Helpers/SlugGenerator.cs
@@ -0,0 +1,108 @@
+using System.Text;
+
+namespace IOL.Helpers
+{
+	public static class Slug
+	{
+		public static string Generate(bool toLower, params string[] values) {
+			return Create(string.Join("-", values), toLower);
+		}
+
+		/// <summary>
+		/// Creates a slug.
+		/// References:
+		/// http://www.unicode.org/reports/tr15/tr15-34.html
+		/// https://meta.stackexchange.com/questions/7435/non-us-ascii-characters-dropped-from-full-profile-url/7696#7696
+		/// https://stackoverflow.com/questions/25259/how-do-you-include-a-webpage-title-as-part-of-a-webpage-url/25486#25486
+		/// https://stackoverflow.com/questions/3769457/how-can-i-remove-accents-on-a-string
+		/// </summary>
+		/// <param name="value"></param>
+		/// <param name="toLower"></param>
+		/// <returns>Slugified string</returns>
+		public static string Create(string value, bool toLower) {
+			if (string.IsNullOrWhiteSpace(value))
+				return value;
+
+			var normalised = value.Normalize(NormalizationForm.FormKD);
+
+			const int MAXLEN = 80;
+			var len = normalised.Length;
+			var prevDash = false;
+			var sb = new StringBuilder(len);
+
+			for (var i = 0; i < len; i++) {
+				var c = normalised[i];
+				switch (c) {
+					case >= 'a' and <= 'z':
+					case >= '0' and <= '9': {
+						if (prevDash) {
+							sb.Append('-');
+							prevDash = false;
+						}
+
+						sb.Append(c);
+						break;
+					}
+					case >= 'A' and <= 'Z': {
+						if (prevDash) {
+							sb.Append('-');
+							prevDash = false;
+						}
+
+						// Tricky way to convert to lowercase
+						if (toLower)
+							sb.Append((char) (c | 32));
+						else
+							sb.Append(c);
+						break;
+					}
+					case ' ':
+					case ',':
+					case '.':
+					case '/':
+					case '\\':
+					case '-':
+					case '_':
+					case '=': {
+						if (!prevDash && sb.Length > 0) {
+							prevDash = true;
+						}
+
+						break;
+					}
+					default: {
+						var swap = ConvertEdgeCases(c, toLower);
+						if (swap != null) {
+							if (prevDash) {
+								sb.Append('-');
+								prevDash = false;
+							}
+
+							sb.Append(swap);
+						}
+
+						break;
+					}
+				}
+
+				if (sb.Length == MAXLEN)
+					break;
+			}
+
+			return sb.ToString();
+		}
+
+		private static string ConvertEdgeCases(char c, bool toLower) => c switch {
+			'ı' => "i",
+			'ł' => "l",
+			'Ł' => toLower ? "l" : "L",
+			'đ' => "d",
+			'ß' => "ss",
+			'ø' => "o",
+			'å' => "aa",
+			'æ' => "ae",
+			'Þ' => "th",
+			_ => null
+		};
+	}
+}
\ No newline at end of file
diff --git a/src/IOL.Helpers/StringHelpers.cs b/src/IOL.Helpers/StringHelpers.cs
new file mode 100644
index 0000000..1dde161
--- /dev/null
+++ b/src/IOL.Helpers/StringHelpers.cs
@@ -0,0 +1,67 @@
+using System;
+using System.Text;
+using System.Text.RegularExpressions;
+
+namespace IOL.Helpers
+{
+	public static class StringHelpers
+	{
+		public static bool IsNullOrWhiteSpace(this string value) {
+			return string.IsNullOrWhiteSpace(value);
+		}
+
+		public static string Slugified(this string input) {
+			return Slug.Generate(true, input);
+		}
+
+		public static bool HasValue(this string value) {
+			return !value.IsNullOrWhiteSpace();
+		}
+
+		public static Guid ToGuid(this string value) {
+			return Guid.Parse(value);
+		}
+
+		public static string Base64Encode(this string text) {
+			return Convert.ToBase64String(Encoding.UTF8.GetBytes(text));
+		}
+
+		public static string ExtractFileName(this string value) {
+			if (value.IsNullOrWhiteSpace()) return default;
+			var lastIndex = value.LastIndexOf('.');
+			return lastIndex <= 0 ? default : value.Substring(0, lastIndex);
+		}
+
+		public static string ExtractExtension(this string value) {
+			if (value.IsNullOrWhiteSpace()) return default;
+			var lastIndex = value.LastIndexOf('.');
+			return lastIndex <= 0 ? default : value.Substring(lastIndex);
+		}
+
+		public static string Capitalize(this string input) {
+			return input.IsNullOrWhiteSpace()
+				? input
+				: Regex.Replace(input, @"\b(\w)", m => m.Value.ToUpper(), RegexOptions.None);
+		}
+
+
+		/// <summary>
+		/// Check if the given MIME is a JSON MIME.
+		/// </summary>
+		/// <param name="mime">MIME</param>
+		/// <returns>Returns true if MIME type is json.</returns>
+		public static bool IsJsonMime(this string mime) {
+			var jsonRegex = new Regex("(?i)^(application/json|[^;/ \t]+/[^;/ \t]+[+]json)[ \t]*(;.*)?$");
+			return mime != null && (jsonRegex.IsMatch(mime) || mime.Equals("application/json-patch+json"));
+		}
+
+		public static string Obfuscate(this string value) {
+			var last4Chars = "****";
+			if (value.HasValue() && value.Length > 4) {
+				last4Chars = value.Substring(value.Length - 4);
+			}
+
+			return "****" + last4Chars;
+		}
+	}
+}
\ No newline at end of file
diff --git a/src/IOL.Helpers/Validators.cs b/src/IOL.Helpers/Validators.cs
new file mode 100644
index 0000000..d60afcf
--- /dev/null
+++ b/src/IOL.Helpers/Validators.cs
@@ -0,0 +1,18 @@
+using System.Net.Mail;
+using System.Text.RegularExpressions;
+
+namespace IOL.Helpers
+{
+	public static class Validators
+	{
+		private static readonly Regex _norwegianPhoneNumber = new(@"^(0047|\+47|47)?[2-9]\d{7}$");
+
+		public static bool IsValidEmailAddress(this string value) {
+			return MailAddress.TryCreate(value, out _);
+		}
+
+		public static bool IsValidNorwegianPhoneNumber(this string value) {
+			return _norwegianPhoneNumber.IsMatch(value);
+		}
+	}
+}
\ No newline at end of file