NewPipe/app/src/main/java/us/shandian/giga/postprocessing/TtmlConverter.java

package us.shandian.giga.postprocessing;

import android.util.Log;

import org.schabi.newpipe.streams.SrtFromTtmlWriter;
import org.schabi.newpipe.streams.io.SharpStream;

import java.io.IOException;

/**
 * @author kapodamy
 */
class TtmlConverter extends Postprocessing {
    private static final String TAG = "TtmlConverter";

    TtmlConverter() {
        // due how XmlPullParser works, the xml is fully loaded on the ram
        super(false, true, ALGORITHM_TTML_CONVERTER);
    }

    @Override
    int process(SharpStream out, SharpStream... sources) throws IOException {
        // check if the subtitle is already in srt and copy, this should never happen
        String format = getArgumentAt(0, null);
        boolean ignoreEmptyFrames = getArgumentAt(1, "true").equals("true");

        if (format == null || format.equals("ttml")) {
            SrtFromTtmlWriter writer = new SrtFromTtmlWriter(out, ignoreEmptyFrames);

            try {
                writer.build(sources[0]);
            } catch (Exception err) {
                Log.e(TAG, "subtitle parse failed", err);
                return err instanceof IOException ? 1 : 8;
            }

            return OK_RESULT;
        } else if (format.equals("srt")) {
            byte[] buffer = new byte[8 * 1024];
            int read;
            while ((read = sources[0].read(buffer)) > 0) {
                out.write(buffer, 0, read);
            }
            return OK_RESULT;
        }

        throw new UnsupportedOperationException("Can't convert this subtitle, unimplemented format: " + format);
    }

}