/// <summary>
/// Tries to parse a text string for takeoff directions. When the text contains
/// parenthesis, only the text in the parenthesis is parsed. The takeoff directions can
/// be single directions, separated by comma, or direction ranges, separated by a dash,
/// or a combination of both.
/// </summary>
/// <param name="text">text to parse</param>
/// <param name="takeoffDirections">flag enum that contains all directions</param>
/// <returns>true when parsing was successful, false when not</returns>
public static bool TryParse(string text, out TakeoffDirections takeoffDirections)
{
takeoffDirections = TakeoffDirections.None;
int startBracket = text.IndexOf("(");
if (startBracket != -1)
{
int endBracket = text.IndexOf(")", startBracket + 1);
if (endBracket != -1)
{
return(TryParse(
text.Substring(startBracket + 1, endBracket - startBracket - 1),
out takeoffDirections));
}
}
text = text.ToUpperInvariant().Replace(" ", string.Empty);
if (text.Any((ch) => !IsValidTakeoffChar(ch)))
{
return(false);
}
text = text.Replace("O", "E"); // replace german east letter
foreach (var range in text.Split(','))
{
if (!TryParseDirectionOrRange(range, ref takeoffDirections))
{
return(false);
}
}
return(true);
}
/// <summary>
/// Tries to parse a start direction from given location description. Some locations, e.g.
/// from the DHV Geländedatenbank, have the start directions in the description, after a
/// certain text.
/// </summary>
/// <param name="description">location description</param>
/// <param name="takeoffDirections">parsed takeoff directions</param>
/// <returns>true when a takeoff direction could be parsed, or false when not</returns>
private static bool TryParseStartDirectionFromDescription(string description, out TakeoffDirections takeoffDirections)
{
takeoffDirections = TakeoffDirections.None;
const string StartDirectionText = "Startrichtung ";
int posStartDirection = description.IndexOf(StartDirectionText);
if (posStartDirection == -1)
{
return(false);
}
int posLineBreak = description.IndexOf("<br", posStartDirection);
if (posLineBreak == -1)
{
posLineBreak = description.Length;
}
posStartDirection += StartDirectionText.Length;
string direction = description.Substring(posStartDirection, posLineBreak - posStartDirection);
return(TakeoffDirectionsHelper.TryParse(direction, out takeoffDirections));
}
