public Dictionary<char, char> Get(string ciphertext, LangCharacteristic lang)
{
ciphertext = ciphertext.Delete(' ');
var letters = TextAnalysis.GetOccurrence(ciphertext, 1);
var topLetters = letters.Take(2).Select(x => x.Key[0]).ToArray();
Dictionary<char, char> res = new Dictionary<char, char>();
res['e'] = topLetters[0];
res['a'] = topLetters[1];
return res;
}
/// <summary>
/// Zjistí, jak moc daný text odpovídá zvyklostem daného jazyka.
/// </summary>
/// <param name="text">Jakýkoliv text daného jazyka</param>
/// <param name="lang">Vlastnosti a charakteristiky jazyka</param>
/// <returns>Procentuální vyjádření shody s vlastnostmi jazyka</returns>
public static double SimilarityIndex(string text, LangCharacteristic lang)
{
double similarity = 0;
similarity += 3 * SumSimilarity(text, lang.Letters);
similarity += SumSimilarity(text, lang.Bigrams);
similarity += SumSimilarity(text, lang.Trigrams);
return similarity;
}
/// <summary>
/// Seřadí klíče od nejpravděpodobnějších po nejméně pravděpodobné
/// </summary>
/// <param name="keys"></param>
/// <param name="ciphertext"></param>
/// <param name="lang"></param>
/// <returns></returns>
private string[] OrderKeys(string[] keys, string ciphertext, LangCharacteristic lang)
{
var opentexts = GetOpentexts(keys, ciphertext);
var probabilities = GetProbabilities(opentexts, keys, lang);
var orderedKeys = probabilities.Keys.ToArray();
return orderedKeys;
}
/// <summary>
/// Zjistí pravděpodobnost jednotlivých klíčů
/// </summary>
/// <param name="opentexts"></param>
/// <param name="keys"></param>
/// <param name="lang"></param>
/// <returns></returns>
private Dictionary<string, int> GetProbabilities(string[] opentexts, string[] keys, LangCharacteristic lang)
{
string[] topTopWords = lang.TopWords.Take(topWordsCount).ToArray();
Dictionary<string, int> probabilities = new Dictionary<string, int>();
for (int i = 0; i < keys.Length; i++)
probabilities[keys[i]] = Analyse.WordsContains(opentexts[i], topTopWords);
return probabilities.OrderByDescending(x => x.Value).ToDictionary(x => x.Key, x => x.Value);
}
/// <summary>
/// Načte z disku požadovaná data
/// </summary>
public static void LoadFiles(Action actionIfNotSucces)
{
try
{
langChars = new Dictionary<Languages, LangCharacteristic>();
var names = Enum.GetNames(typeof(Languages));
foreach (string name in names)
{
Languages l = (Languages)Enum.Parse(typeof(Languages), name);
langChars[l] = new LangCharacteristic(l);
}
}
catch (Exception)
{
actionIfNotSucces();
}
}
