package org.esigate.extension.surrogate.http;
   
   import java.util.ArrayList;
   import java.util.List;
   
   import org.apache.commons.lang3.StringUtils;
   
   /**
    * The name in each capability set identifies a device token, which uniquely identifies the surrogate that appended it.
   * Device tokens must be unique within a request's Surrogate-Capabilities header.
   * <p>
   * The value contains a space-separated list of capability tokens.
   * 
   * @author Nicolas Richeton
   * 
   */
  public final class SurrogateCapabilities {
      private List<Capability> capabilities;
      private String deviceToken;
  
      public List<Capability> getCapabilities() {
          return capabilities;
      }
  
      public String getDeviceToken() {
          return deviceToken;
      }
  
      private SurrogateCapabilities() {
          capabilities = new ArrayList<>();
          deviceToken = null;
      }
  
      public static SurrogateCapabilities fromString(String surrogateString) {
          SurrogateCapabilities cap = new SurrogateCapabilities();
          int equalsIndex = surrogateString.indexOf('=');
  
          if (equalsIndex >= 0) {
  
              cap.deviceToken = surrogateString.substring(0, equalsIndex).trim();
  
              String allCapabiities = surrogateString.substring(equalsIndex + 1).trim();
  
              if (allCapabiities.startsWith("\"") && allCapabiities.endsWith("\"")) {
                  allCapabiities = allCapabiities.substring(1, allCapabiities.length() - 1);
              }
              String[] capabilities = allCapabiities.split(" ");
              for (String c : capabilities) {
  
                  c = c.trim();
  
                  if (c.length() > 0) {
                      cap.capabilities.add(Capability.fromToken(c));
                  }
              }
  
          }
          return cap;
      }
  
      @Override
      public String toString() {
          return deviceToken + "=" + "\"" + StringUtils.join(capabilities, " ") + "\"";
      }
  }