using System;
using System.Collections.Generic;
using System.Data.SqlClient;
using System.Text;

namespace Concurrency
{
    public class TemporaryConstraint : IDisposable
    {
        private readonly SqlCommand _command;
        private readonly string _constraintName;

        public TemporaryConstraint(SqlConnection connection, string schemaName, 
            string tableName, string constraintBody)
        {
            _command = connection.CreateCommand();
            _constraintName = string.Format("[{0}_{1}_TemporaryConstraint]", schemaName, tableName);
            try
            {
                _command.CommandText =
                    string.Format(
                        "ALTER TABLE {0}.{1} DROP CONSTRAINT {2}",
                        schemaName, tableName, _constraintName);
                _command.ExecuteNonQuery();
            }
            catch(Exception e)
            {
                //Console.WriteLine(e);
            }
            _command.CommandText = string.Format("ALTER TABLE {0}.{1} WITH NOCHECK ADD CONSTRAINT {2} CHECK({3})",
                                                 schemaName, tableName, _constraintName, constraintBody);
            _command.ExecuteNonQuery();
            _command.CommandText = string.Format("ALTER TABLE {0}.{1} DROP CONSTRAINT {2}",
                                                 schemaName, tableName, _constraintName);
        }

        public void Dispose()
        {
            _command.ExecuteNonQuery(); 
        }
    }
}