package org.daisy.pipeline.css;
   
   import java.util.Optional;
   
   import org.daisy.common.xpath.saxon.ExtensionFunctionProvider;
   import org.daisy.common.xpath.saxon.ReflexiveExtensionFunctionProvider;
   
   import org.osgi.service.component.annotations.Component;
   
  import org.w3c.dom.Element;
  
  public interface StyleAccessor {
  
  	@Component(
  		name = "StyleAccesor",
  		service = { ExtensionFunctionProvider.class }
  	)
  	public static class Provider extends ReflexiveExtensionFunctionProvider {
  		public Provider() {
  			super(StyleAccessor.class);
  		}
  	}
  
  	/**
  	 * Get the <a
  	 * href="https://www.w3.org/TR/2013/CR-css-cascade-3-20131003/#specified">specified
  	 * value</a> of a CSS property and element.
  	 */
  	public Optional<String> get(Element element, String property);
  
  	/**
  	 * Test whether an element matches a CSS selector.
  	 *
  	 * @throws IllegalArgumentException if the selector can not be compiled
  	 */
  	public boolean matches(Element element, String selector);
  
  }