using System.DirectoryServices.Protocols;

namespace LdapLoginLib
{
    public class LoginLib
    {
        private const string _ldapServer = "10.31.3.13";
        private const int _ldapPort = 389;

        private const string _ldapDn = "ou=People,o=unal.edu.co"; //uid=pdocente,
        //string ldapPassword = "TJBjzn64";

        

        public static bool Login(string uid, string password, string ldapDn = _ldapDn)
        {

            using (LdapConnection ldapConnection = new($"{_ldapServer}:{_ldapPort}"))
            {
                try
                {
                    string ldapUserDn = $"uid={uid},{_ldapDn}";

                    // Set LDAP connection options
                    ldapConnection.SessionOptions.SecureSocketLayer = false;
                    ldapConnection.AuthType = AuthType.Basic;
                    ldapConnection.Credential = new System.Net.NetworkCredential(ldapUserDn, password);

                    // Attempt to bind (authenticate) the user
                    ldapConnection.Bind();

                    return _userIsActive(ldapConnection, ldapUserDn);
                }
                catch (LdapException ldapEx)
                {
                    //Console.WriteLine($"Authentication failed: {ldapEx.Message}");
                    throw new Exception(_getErrorMessage(ldapEx.ErrorCode, ldapEx.Message));
                }
                catch (Exception ex)
                {
                    //Console.WriteLine($"An error occurred: {ex.Message}");
                    throw new Exception($"Ocurrió un error: {ex.Message}");
                }

            }
        }

        private static bool _userIsActive(LdapConnection ldapConnection, string ldapUserDn)
        {
            //ldapUserDn = $"uid=acbuitragoc,{_ldapDn}";
            SearchRequest searchRequest = new(
                        ldapUserDn,
                        "(objectClass=*)",
                        SearchScope.Base,
                        "InetUserStatus"
                    );

            SearchResponse searchResponse = (SearchResponse)ldapConnection.SendRequest(searchRequest);

            if (searchResponse.Entries.Count > 0)
            {
                SearchResultEntry entry = searchResponse.Entries[0];

                string? inetUserStatus = entry.Attributes["inetUserStatus"][0].ToString();

                if (inetUserStatus != null)
                {
                    return inetUserStatus.ToLower().Trim() == "active" ? true : false;
                }
                throw new Exception();
            }
            else
            {
                throw new Exception($"Usuario o atributo no encontrado.");
            }
        }


        private static LdapUser _getUserData(LdapConnection ldapConnection, string ldapUserDn, string[] attributesToReturn)
        {

            return new LdapUser();


            //SearchRequest searchRequest = new(
            //    searchBase,
            //    ldapFilter,
            //    SearchScope.Subtree,
            //    attributesToReturn
            //);

            //SearchResponse searchResponse = (SearchResponse)ldapConnection.SendRequest(searchRequest);


            //if (searchResponse != null && searchResponse.Entries.Count > 0)
            //{
            //    SearchResultEntry entry = searchResponse.Entries[0];

            //    // Access and process user attributes here
            //    foreach (DirectoryAttribute attribute in entry.Attributes.Values)
            //    {
            //        string attributeName = attribute.Name;
            //        string[] attributeValues = (string[])attribute.GetValues(typeof(string));

            //        // Process or display attribute values as needed
            //        Console.WriteLine($"{attributeName}: {string.Join(", ", attributeValues)}");
            //    }
            //}
            //else
            //{
            //    throw new Exception($"Usuario o atributos no encontrados.");
            //}
        }


        private static string _getErrorMessage(int errorCode, string errorMessage)
        {
            // Map LDAP error codes to error messages

            switch (errorCode)
            {
                case 49:
                    return "Error de credenciales: nombre de usuario o contraseña incorrectos";
                case 52:
                    return "Error de autenticación: cuenta está deshabilitada";
                case 81:
                    return "Error de servidor: no disponible";
                default:
                    return errorMessage;
            }
        }
    }
}