import java.io.Closeable;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.OutputStreamWriter;
import java.nio.charset.Charset;

class WordListWriter implements Closeable {

  private final XmlWriter mXmlWriter;
  private long mWordsWritten;

  WordListWriter(File outputWordsListFile) throws IOException {
    final File parentFile = outputWordsListFile.getParentFile();
    if (!parentFile.exists() && !parentFile.mkdirs()) {
      throw new IllegalArgumentException(
          "Failed to create output folder " + parentFile.getAbsolutePath());
    }
    OutputStreamWriter outputWriter =
        new OutputStreamWriter(new FileOutputStream(outputWordsListFile), Charset.forName("UTF-8"));
    mXmlWriter = new XmlWriter(outputWriter, true, 0, true);
    mXmlWriter.writeEntity("wordlist");
  }

  public static void writeWordWithRuntimeException(
      WordListWriter writer, String word, int frequency) {
    try {
      writer.addEntry(word, frequency);
    } catch (IOException e) {
      throw new RuntimeException(e);
    }
  }

  public void addEntry(String word, int frequency) throws IOException {
    mXmlWriter
        .writeEntity("w")
        .writeAttribute("f", Integer.toString(frequency))
        .writeText(word)
        .endEntity();
    mWordsWritten++;
  }

  @Override
  public void close() throws IOException {
    mXmlWriter.endEntity();
    System.out.println("Wrote " + mWordsWritten + " words.");
    mXmlWriter.close();
  }

  private static int calcActualFreq(double wordIndex, double wordsCount) {
    return Math.min(255, 1 + (int) (255 * (wordsCount - wordIndex) / wordsCount));
  }
}
