using InnovEnergy.SysTools.Edges;
using InnovEnergy.SysTools.Utils;

namespace InnovEnergy.SysTools.Remote;

public readonly struct SshHost
{
    public const Int32 DefaultPort = 22;

    public String   User    { get; }
    public String   Address { get; }
    public Int32    Port    { get; }
    public SysPath? KeyFile { get; }

    public SshHost(String user, String address, Int32 port = DefaultPort)
    {
        User    = user;
        Address = address;
        KeyFile = null;
        Port    = port;
    }

    public SshHost(String user, String address, SysPath? keyFile, Int32 port = DefaultPort)
    {
        User    = user;
        Address = address;
        KeyFile = keyFile;
        Port    = port;
    }

    public static SshHost Parse(String userAtAddressColonPort)
    {
        var addressPort = userAtAddressColonPort.AfterFirst('@').Split(':');

        var user    = userAtAddressColonPort.UntilFirst('@');
        var address = addressPort[0];
        var port    = addressPort.Length < 2 ? DefaultPort : Int32.Parse(addressPort[1]);

        return new SshHost(user, address, null, port);
    }

    public static SshHost Parse(String userAtAddressColonPort, SysPath keyFile)
    {
        var addressPort = userAtAddressColonPort.AfterFirst('@').Split(':');

        var user    = userAtAddressColonPort.UntilFirst('@');
        var address = addressPort[0];
        var port    = addressPort.Length < 2 ? DefaultPort : Int32.Parse(addressPort[1]);

        return new SshHost(user, address, keyFile, port);
    }



    public static SshHost Localhost { get; } = new SshHost(Environment.UserName, "127.0.0.1");

    public Boolean IsLocalhost => Equals(Localhost);

    public override String ToString() => $"{User}@{Address}";

    #region equality

    public Boolean Equals(SshHost other)
    {
        return User == other.User &&
               Address == other.Address &&
               Port == other.Port &&
               Nullable.Equals(KeyFile, other.KeyFile);
    }

    public override Boolean Equals(Object obj)
    {
        return obj is SshHost other && Equals(other);
    }

    public override Int32 GetHashCode()
    {
        unchecked
        {
            var hashCode = (User != null ? User.GetHashCode() : 0);
            hashCode = (hashCode * 397) ^ (Address != null ? Address.GetHashCode() : 0);
            hashCode = (hashCode * 397) ^ Port;
            hashCode = (hashCode * 397) ^ KeyFile.GetHashCode();
            return hashCode;
        }
    }

    #endregion

    public static RemotePath operator / (SshHost host, SysPath path) => host.WithPath(path);
    public static RemotePath operator / (SshHost host, String  path)
    {
        return host.WithPath(path.ToPath().ToAbsolute());
    }

    public void Deconstruct(out String user, out String address, out SysPath? keyFile)
    {
        user    = User;
        address = Address;
        keyFile = KeyFile;
    }
}