package us.codecraft.webmagic.selector;
   
   
   import java.util.ArrayList;
   import java.util.List;
   
   import org.apache.commons.collections4.CollectionUtils;
   
   /**
   * @author code4crafer@gmail.com
   * @since 0.5.2
   */
  public abstract class AbstractSelectable implements Selectable {
  
      protected abstract List<String> getSourceTexts();
  
      @Override
      public Selectable css(String selector) {
          return $(selector);
      }
  
      @Override
      public Selectable css(String selector, String attrName) {
          return $(selector, attrName);
      }
  
      protected Selectable select(Selector selector, List<String> strings) {
          List<String> results = new ArrayList<String>();
          for (String string : strings) {
              String result = selector.select(string);
              if (result != null) {
                  results.add(result);
              }
          }
          return new PlainText(results);
      }
  
      protected Selectable selectList(Selector selector, List<String> strings) {
          List<String> results = new ArrayList<String>();
          for (String string : strings) {
              List<String> result = selector.selectList(string);
              results.addAll(result);
          }
          return new PlainText(results);
      }
  
      @Override
      public List<String> all() {
          return getSourceTexts();
      }
  
      @Override
      public Selectable jsonPath(String jsonPath) {
          throw new UnsupportedOperationException();
      }
  
      @Override
      public String get() {
      	List<String> sourceTexts = all();
          if (CollectionUtils.isNotEmpty(sourceTexts)) {
              return sourceTexts.get(0);
          } 
          return null;
          
      }
  
      @Override
      public Selectable select(Selector selector) {
          return select(selector, getSourceTexts());
      }
  
      @Override
      public Selectable selectList(Selector selector) {
          return selectList(selector, getSourceTexts());
      }
  
      @Override
      public Selectable regex(String regex) {
          RegexSelector regexSelector = Selectors.regex(regex);
          return selectList(regexSelector, getSourceTexts());
      }
  
      @Override
      public Selectable regex(String regex, int group) {
          RegexSelector regexSelector = Selectors.regex(regex, group);
          return selectList(regexSelector, getSourceTexts());
      }
  
      @Override
      public Selectable replace(String regex, String replacement) {
          ReplaceSelector replaceSelector = new ReplaceSelector(regex,replacement);
          return select(replaceSelector, getSourceTexts());
      }
  
      public String getFirstSourceText() {
      	List<String> sourceTexts = getSourceTexts();
          if (CollectionUtils.isNotEmpty(sourceTexts)) {
              return sourceTexts.get(0);
          }
         return null;
     }
 
     @Override
     public String toString() {
         return get();
     }
 
     @Override
     public boolean match() {
         return CollectionUtils.isNotEmpty(getSourceTexts());
     }
 }