Migrate existing code

Integrations/Kea/KeaDhcp4Lease.cs

@@ -0,0 +1,142 @@
+using System.Net;
+using System.Net.NetworkInformation;
+
+using nietras.SeparatedValues;
+
+using Cell = System.ReadOnlySpan<char>;
+
+namespace DotNetDDI.Integrations.Kea;
+
+using Lease = KeaDhcp4Lease;
+
+// ref: https://github.com/isc-projects/kea/blob/Kea-2.5.3/src/lib/dhcpsrv/csv_lease_file4.h
+public record struct KeaDhcp4Lease(
+	IPAddress Address,
+	PhysicalAddress HWAddr,
+	string? ClientId,
+	TimeSpan ValidLifetime,
+	DateTimeOffset Expire,
+	uint SubnetId,
+	bool FqdnFwd,
+	bool FqdnRev,
+	string Hostname,
+	uint State,
+	string? UserContext,
+	uint PoolId)
+{
+	public static Lease? Parse(in SepReader.Row row)
+	{
+		Lease result = new();
+		for (int i = 0; i < row.ColCount; i++)
+		{
+			if (Parse(ref result, i, row[i].Span) == false)
+			{
+				return null;
+			}
+		}
+
+		return result;
+	}
+
+	private static bool? Parse(ref Lease lease, int column, in Cell span)
+	{
+		return column switch
+		{
+			0 => ToIPAddress(ref lease, span),
+			1 when !span.IsWhiteSpace() => ToHWAddr(ref lease, span),
+			2 => ToClientId(ref lease, span),
+			3 => ToValidLifetime(ref lease, span),
+			4 => ToExpire(ref lease, span),
+			5 => ToSubnetId(ref lease, span),
+			6 => ToFqdnFwd(ref lease, span),
+			7 => ToFqdnRev(ref lease, span),
+			8 => ToHostname(ref lease, span),
+			9 => ToState(ref lease, span),
+			10 => ToUserContext(ref lease, span),
+			11 => ToPoolId(ref lease, span),
+
+			_ => null
+		};
+
+		static bool ToIPAddress(ref Lease lease, in Cell span)
+		{
+			bool result = IPAddress.TryParse(span, out var address);
+			lease.Address = address!;
+			return result;
+		}
+
+		static bool ToHWAddr(ref Lease lease, in Cell span)
+		{
+			bool result = PhysicalAddress.TryParse(span, out var hwaddr);
+			lease.HWAddr = hwaddr!;
+			return result;
+		}
+
+		static bool ToClientId(ref Lease lease, in Cell span)
+		{
+			lease.ClientId = span.ToString();
+			return true;
+		}
+
+		static bool ToValidLifetime(ref Lease lease, in Cell span)
+		{
+			bool result = uint.TryParse(span, out var validLifetime);
+			lease.ValidLifetime = TimeSpan.FromSeconds(validLifetime);
+			return result;
+		}
+
+		static bool ToExpire(ref Lease lease, in Cell span)
+		{
+			bool result = ulong.TryParse(span, out var expire);
+			lease.Expire = DateTimeOffset.FromUnixTimeSeconds(unchecked((long)expire));
+			return result;
+		}
+
+		static bool ToSubnetId(ref Lease lease, in Cell span)
+		{
+			bool result = uint.TryParse(span, out var subnetId);
+			lease.SubnetId = subnetId;
+			return result;
+		}
+
+		static bool ToFqdnFwd(ref Lease lease, in Cell span)
+		{
+			bool result = byte.TryParse(span, out var fqdnFwd);
+			lease.FqdnFwd = fqdnFwd != 0;
+			return result;
+		}
+
+		static bool ToFqdnRev(ref Lease lease, in Cell span)
+		{
+			bool result = byte.TryParse(span, out var fqdnRev);
+			lease.FqdnRev = fqdnRev != 0;
+			return result;
+		}
+
+		static bool ToHostname(ref Lease lease, in Cell span)
+		{
+			lease.Hostname = KeaDhcpLease.Unescape(span);
+			return true;
+		}
+
+		static bool ToState(ref Lease lease, in Cell span)
+		{
+			bool result = uint.TryParse(span, out var state);
+			lease.State = state;
+			return result;
+		}
+
+		static bool ToUserContext(ref Lease lease, in Cell span)
+		{
+			lease.UserContext = KeaDhcpLease.Unescape(span);
+			return true;
+		}
+
+		static bool ToPoolId(ref Lease lease, in Cell span)
+		{
+			bool result = uint.TryParse(span, out var poolId);
+			lease.PoolId = poolId;
+			return result;
+		}
+	}
+}