{

internal string Database { get; set; }

internal string Username { get; set; }

internal string ApplicationName { get; set; }

internal string SearchPath { get; set; }

Dictionary<byte[], byte[]> _parameters;

int _length;

const int ProtocolVersion3 = 3 << 16; // 196608

internal StartupMessage(string database, string username)

{

Database = database;

Username = username;

}

internal override void Prepare()

{

Contract.Requires(!String.IsNullOrWhiteSpace(Database));

Contract.Requires(!String.IsNullOrWhiteSpace(Username));

var parameters = new Dictionary<String, String> {

{ "database", Database },

{ "user", Username },

{ "client_encoding", "UTF8" },

};

if (ApplicationName != null)

{

parameters.Add("application_name", ApplicationName);

}

if (SearchPath != null)

{

parameters.Add("search_path", SearchPath);

}

// TODO: Is this really UTF8 or can be ASCII?

_parameters = parameters.ToDictionary(kv => PGUtil.UTF8Encoding.GetBytes(kv.Key),

kv => PGUtil.UTF8Encoding.GetBytes(kv.Value));

_length = 4 + // len

4 + // protocol version

_parameters.Select(kv => kv.Key.Length + kv.Value.Length + 2).Sum() +

1; // trailing zero byte

}

internal override int Length { get { return _length; } }

internal override void Write(NpgsqlBuffer buf)

{

buf.WriteInt32(_length);

buf.WriteInt32(ProtocolVersion3);

foreach (var kv in _parameters)

{

buf.WriteBytesNullTerminated(kv.Key);

buf.WriteBytesNullTerminated(kv.Value);

}

buf.WriteByte(0);

}