import java.io.*;
import java.util.*;
import java.util.stream.Collectors;

public class App {

    public static void main(String[] args) throws Exception {
        File directoryPath = new File("in/");
        String[] files = directoryPath.list();
        assert files != null;

        if (files.length < 10) {
            throw new NotEnoughFilesException("Not enough files in the directory");
        }
        for (var fileName : files) {
            File file = new File("in/" + fileName);
            if (file.length() < 150 * 1024) {
                throw new FileTooSmallException("File " + fileName + " is too small");
            }
        }

        LinkedHashMap<String, Integer> dict = new LinkedHashMap<>();

        for (var fileName : files) {
            File file = new File("in/" + fileName);
            BufferedReader reader = new BufferedReader(new FileReader(file));
            String st;
            StringBuilder contents = new StringBuilder();
            while ((st = reader.readLine()) != null) {
                contents.append(st).append("\n");
            }
            String[] words = contents.toString().split("\\s");

            for (var word : words) {
                if (word.length() > 0) {
                    String fmt = word.replaceAll("[^\\w\\p{sc=Cyrillic}]+", "").toLowerCase();
                    int count;
                    if (dict.containsKey(fmt)) {
                        count = dict.get(fmt) + 1;
                    } else {
                        count = 1;
                    }
                    dict.put(fmt, count);
                }
            }
        }

        LinkedHashMap<String, Integer> sortedDict = dict.entrySet().stream().sorted(Map.Entry.comparingByValue(Comparator.reverseOrder())).collect(Collectors.toMap(Map.Entry::getKey, Map.Entry::getValue, (e1, e2) -> e1, LinkedHashMap::new));

        int wordCount = sortedDict.values().stream().mapToInt(i -> i).sum();
        int termCount = sortedDict.size();

        File file = new File("dict.txt");
        BufferedWriter writer = new BufferedWriter(new FileWriter(file));
        for (var entry : sortedDict.entrySet()) {
            writer.write(entry.getKey() + " -- " + entry.getValue() + "\n");
        }
        writer.flush();
        long size = file.length();

        System.out.printf("Dictionary size: %.2f KB\n", (double) size / 1024.0);
        System.out.println("Word count: " + wordCount);
        System.out.println("Term count: " + termCount);

        writer.close();
    }
}