using System;
using System.Net;

namespace AMWD.Common.Tests.Extensions
{
	[TestClass]
	public class IPAddressExtensionsTest
	{
		[TestMethod]
		public void ShouldIncrementLastByte()
		{
			// arrange
			var ipAddress = IPAddress.Parse("192.168.178.22");

			// act
			var incremented = ipAddress.Increment();

			// assert
			Assert.AreEqual("192.168.178.23", incremented.ToString());
		}

		[TestMethod]
		public void ShouldIncrementAllBytes()
		{
			// arrange
			var ipAddress = IPAddress.Parse("192.255.255.255");

			// act
			var incremented = ipAddress.Increment();

			// assert
			Assert.AreEqual("193.0.0.0", incremented.ToString());
		}

		[TestMethod]
		public void ShouldIncrementOverflow()
		{
			// arrange
			var ipAddress = IPAddress.Parse("255.255.255.255");

			// act
			var incremented = ipAddress.Increment();

			// assert
			Assert.AreEqual("0.0.0.0", incremented.ToString());
		}

		[TestMethod]
		public void ShouldDecrementLastByte()
		{
			// arrange
			var ipAddress = IPAddress.Parse("192.168.178.22");

			// act
			var decremented = ipAddress.Decrement();

			// assert
			Assert.AreEqual("192.168.178.21", decremented.ToString());
		}

		[TestMethod]
		public void ShouldDecrementAllBytes()
		{
			// arrange
			var ipAddress = IPAddress.Parse("192.0.0.0");

			// act
			var decremented = ipAddress.Decrement();

			// assert
			Assert.AreEqual("191.255.255.255", decremented.ToString());
		}

		[TestMethod]
		public void ShouldDecrementUnderflow()
		{
			// arrange
			var ipAddress = IPAddress.Parse("0.0.0.0");

			// act
			var decremented = ipAddress.Decrement();

			// assert
			Assert.AreEqual("255.255.255.255", decremented.ToString());
		}

		[TestMethod]
		public void ShouldReturnCleanMappedIPAddressString()
		{
			// arrange
			var mapped = IPAddress.Parse("::ffff:192.168.0.1");

			// act
			string cleaned = mapped.ToCleanString();

			// assert
			Assert.AreEqual("192.168.0.1", cleaned);
		}

		[TestMethod]
		public void ShouldReturnCleanIPv6String()
		{
			// arrange
			var ipv6 = IPAddress.Parse("2001:db8::1");

			// act / assert
			Assert.AreEqual("2001:db8::1", ipv6.ToCleanString());
		}

		[TestMethod]
		[DataRow(0, "0.0.0.0")]
		[DataRow(32, "255.255.255.255")]
		[DataRow(8, "255.0.0.0")]
		[DataRow(12, "255.240.0.0")]
		[DataRow(24, "255.255.255.0")]
		[DataRow(23, "255.255.254.0")]
		public void ShouldReturnSubnetMask(int cidr, string expected)
		{
			// arrange

			// act
			string mask = cidr.ToSubnetMask().ToString();

			// assert
			Assert.AreEqual(expected, mask);
		}

		[TestMethod]
		[DataRow(-1)]
		[DataRow(33)]
		public void ShouldThrowArgumentOutOfRangeExceptionForInvalidSubnetMask(int cidr)
		{
			// arrange

			// act & assert
			Assert.ThrowsExactly<ArgumentOutOfRangeException>(() => cidr.ToSubnetMask());
		}

		[TestMethod]
		public void ShouldObfuscateIPv4()
		{
			// arrange
			var ip = IPAddress.Parse("192.168.0.100");

			// act
			string ob = ip.ObfuscateIpAddress();

			// assert
			Assert.AreEqual("•.168.•.100", ob);
		}

		[TestMethod]
		public void ShouldObfuscateIpAddressWithCustomString()
		{
			// arrange
			var ip = IPAddress.Parse("10.0.0.5");

			// act
			string ob = ip.ObfuscateIpAddress("X");

			// assert
			Assert.AreEqual("X.0.X.5", ob);
		}

		[TestMethod]
		public void ShouldNotObfuscateLocalhostIPv4()
		{
			// arrange
			var ip = IPAddress.Parse("127.0.0.1");

			// act
			string ob = ip.ObfuscateIpAddress();

			// assert
			Assert.AreEqual("127.0.0.1", ob);
		}

		[TestMethod]
		public void ShouldObfuscatedMappedIP()
		{
			// arrange
			var ip = IPAddress.Parse("::ffff:10.0.0.5");

			// act
			string ob = ip.ObfuscateIpAddress("X");

			// assert
			Assert.AreEqual("X.0.X.5", ob);
		}

		[TestMethod]
		public void ShouldObfuscateIPv6()
		{
			// arrange
			var ip = IPAddress.Parse("2001:0db8:85a3:0000:0000:8a2e:0370:7334");

			// act
			string ob = ip.ObfuscateIpAddress();

			// assert
			Assert.AreEqual("•:db8:•::•:370:•", ob);
		}

		[TestMethod]
		public void ShouldNotObfuscateLocalhostIPv6()
		{
			// arrange
			var ip = IPAddress.Parse("::1");

			// act
			string ob = ip.ObfuscateIpAddress();

			// assert
			Assert.AreEqual("::1", ob);
		}
	}
}