/// <summary>
/// Converts the IRC statement into an IRC string containing all of its bytes,
/// including the ending CR+LF, and additionally returns whether the string was truncated.
/// </summary>
/// <param name="truncated"><c>true</c> if the string was too long and had to be truncated.</param>
/// <returns>An IRC string.</returns>
public IrcString ToIrcString(out bool truncated)
{
string errorMessage;
if (!IrcValidation.ValidateStatement(this, out errorMessage))
{
throw new InvalidOperationException(errorMessage);
}
// Convert to an IrcString first.
truncated = false; var @string = IrcString.Empty;
if (Source != null)
{
@string += ":" + Source.ToIrcString() + " ";
}
@string += Command;
for (int i = 0; i < Parameters.Count; i++)
{
var parameter = Parameters[i];
@string += " ";
if (i == Parameters.Count - 1 && parameter.Contains((byte)' '))
{
@string += ":";
}
@string += parameter;
}
// Now convert to a byte array, truncate if need be, and add CR+LF.
if (@string.Length > IrcConstants.MaxStatementLength - 2)
{
@string = @string.Substring(0, IrcConstants.MaxStatementLength - 2);
truncated = true;
}
@string += "\r\n";
return(@string);
}
/// <summary>
/// Tries to read a buffer and parse out an IRC statement.
/// Additionally, on failure, the reason for failure is returned.
/// </summary>
/// <param name="buffer">The buffer to read from.</param>
/// <param name="offset">The offset to begin reading. The parser may advance this, even if parsing fails.</param>
/// <param name="count">The maximum number of bytes to read.</param>
/// <param name="statement">The statement, if parsing succeeds, or <c>null</c>.</param>
/// <param name="parseResult">The result of parsing. On failure, this is the reason for the failure.</param>
/// <returns><c>true</c> if parsing succeeded.</returns>
public static bool TryParse(byte[] buffer, ref int offset, int count,
out IrcStatement statement, out IrcStatementParseResult parseResult)
{
Throw.If.Null(buffer, "buffer");
string errorMessage = null;
IrcString[] parts;
statement = null; parseResult = IrcStatementParseResult.NothingToParse;
// First, skip all initial CR/LF.
SkipCrlf(buffer, ref offset, ref count);
// See if we've got a CR or LF anywhere.
int crlfIndex = IrcString.IndexOf(buffer, @byte => @byte == 13 || @byte == 10, offset, count);
if (crlfIndex == -1)
{
if (count >= IrcConstants.MaxStatementLength)
{
parseResult = IrcStatementParseResult.StatementTooLong;
}
return(false);
}
// OK, let's get our string.
var @string = new IrcString(buffer, offset, crlfIndex - offset);
#if DEBUG
var debugString = @string;
#endif
offset += @string.Length + 1; count -= @string.Length + 1;
SkipCrlf(buffer, ref offset, ref count);
if (crlfIndex >= IrcConstants.MaxStatementLength)
{
parseResult = IrcStatementParseResult.StatementTooLong; return(false);
}
// Do we have a prefix?
statement = new IrcStatement();
if (@string.Length >= 1 && @string[0] == (byte)':')
{
parts = @string.Split((byte)' ', 2);
var sourceString = parts[0].Substring(1); IrcIdentity source;
if (!IrcIdentity.TryParse(sourceString, out source))
{
goto invalid;
}
statement.Source = source;
@string = parts.Length >= 2 ? parts[1] : IrcString.Empty;
}
// Now get the command.
parts = @string.Split((byte)' ', 2);
statement.Command = parts[0];
@string = parts.Length >= 2 ? parts[1] : IrcString.Empty;
// Parameters, now...
while (@string.Length > 0)
{
if (@string[0] == (byte)':')
{
statement.Parameters.Add(@string.Substring(1));
break;
}
else
{
parts = @string.Split((byte)' ', 2);
statement.Parameters.Add(parts[0]);
if (parts.Length == 1)
{
break;
}
@string = parts[1];
}
}
// We're done. If everything's kosher, we'll return true.
if (!IrcValidation.ValidateStatement(statement, out errorMessage))
{
goto invalid;
}
parseResult = IrcStatementParseResult.OK;
return(true);
invalid:
#if DEBUG
Console.WriteLine("Invalid statement '{0}' (error '{1}').", debugString, errorMessage);
#endif
statement = null; parseResult = IrcStatementParseResult.InvalidStatement;
return(false);
}
