/// <summary>
/// Given the first few bytes of content, decide what the FileCategory
/// should be, based on what's in the Content.<br/>
/// This should be called before deciding how to set the content.
/// </summary>
/// <param name="firstBytes">At least the first four bytes of the file read in binary form - can be longer if you wish</param>
/// <returns>The type that should be used to store this file.</returns>
public static FileCategory IdentifyCategory(byte[] firstBytes)
{
var firstFour = new Byte[4];
int atMostFour = Math.Min(4, firstBytes.Length);
Array.Copy(firstBytes, 0, firstFour, 0, atMostFour);
var returnCat = (atMostFour < 4) ? FileCategory.TOOSHORT : FileCategory.OTHER; // default if none of the conditions pass
if (firstFour.SequenceEqual(CompiledObject.MagicId))
{
returnCat = FileCategory.KSM;
}
else
{
bool isAscii = firstFour.All(b => b == (byte)'\n' || b == (byte)'\t' || b == (byte)'\r' || (b >= (byte)32 && b <= (byte)127));
if (isAscii)
returnCat = FileCategory.ASCII;
}
return returnCat;
// There is not currently an explicit test for KERBOSRIPT versus other types of ASCII.
// At current, any time you want to test for is Kerboscript, make sure to test for is ASCII too,
// since nothing causes a file to become type kerboscript yet.
}
