package au.gov.amsa.streams;
   
   import java.io.File;
   import java.io.Reader;
   import java.nio.charset.Charset;
   
   import rx.Observable;
   import rx.functions.Func1;
   
  /**
   * Utilities for stream processing of lines of text from
   * <ul>
   * <li>sockets</li>
   * </ul>
   */
  public final class Strings {
  
      public static final Charset DEFAULT_CHARSET = Charset.forName("UTF-8");
  
      /**
       * Returns null if input is null otherwise returns input.toString().trim().
       */
      public static Func1<Object, String> TRIM = new Func1<Object, String>() {
  
          @Override
          public String call(Object input) {
              if (input == null)
                  return null;
              else
                  return input.toString().trim();
          }
      };
  
      public static Observable<String> from(final Reader reader, final int size) {
          return new OnSubscribeReader(reader, size).toObservable();
          // return StringObservable.from(reader, size);
      }
  
      public static Observable<String> from(Reader reader) {
          return from(reader, 8192);
      }
  
      public static Observable<String> lines(Reader reader) {
          return from(reader, 8192).compose(com.github.davidmoten.rx.Transformers.split("\n"));
      }
  
      public static Observable<String> lines(File file) {
          return from(file).compose(com.github.davidmoten.rx.Transformers.split("\n"));
      }
  
      public static Observable<String> from(File file) {
          return from(file, DEFAULT_CHARSET);
      }
  
      public static Observable<String> split(Observable<String> o, String pattern) {
          return o.compose(com.github.davidmoten.rx.Transformers.split(pattern));
      }
  
      public static Observable<String> split(Observable<String> o, int maxItemLength, String pattern, int maxPatternLength) {
          return o.compose(com.github.davidmoten.rx.Transformers.split(maxItemLength, pattern, maxPatternLength));
      }
  
      
      public static Observable<String> from(final File file, final Charset charset) {
          return com.github.davidmoten.rx.Strings.from(file, charset);
      }
  
  }