content: package act.mail.bytecode;
  
  /*-
   * #%L
   * ACT Framework
   * %%
   * Copyright (C) 2014 - 2017 ActFramework
   * %%
   * Licensed under the Apache License, Version 2.0 (the "License");
   * you may not use this file except in compliance with the License.
   * You may obtain a copy of the License at
   * 
   *      http://www.apache.org/licenses/LICENSE-2.0
   * 
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   * #L%
   */
  
  import act.app.App;
  import act.asm.ClassVisitor;
  import act.asm.MethodVisitor;
  import act.asm.Type;
  import act.mail.meta.MailerClassMetaInfo;
  import act.mail.meta.MailerClassMetaInfoHolder;
  import act.mail.meta.SenderMethodMetaInfo;
  import act.util.AppByteCodeEnhancer;
  import org.osgl.$;
  
  /**
   * Enhance mailer class
   */
  public class MailerEnhancer extends AppByteCodeEnhancer<MailerEnhancer> {
  
      private MailerClassMetaInfoHolder classInfoHolder;
      private String className;
  
      public MailerEnhancer() {
      }
  
      public MailerEnhancer(ClassVisitor cv, MailerClassMetaInfoHolder infoHolder) {
          super(_F.isMailer(infoHolder), cv);
          this.classInfoHolder = infoHolder;
      }
  
      @Override
      public AppByteCodeEnhancer app(App app) {
          this.classInfoHolder = app.classLoader();
          return super.app(app);
      }
  
      @Override
      protected Class<MailerEnhancer> subClass() {
          return MailerEnhancer.class;
      }
  
      @Override
      protected void reset() {
          className = null;
          super.reset();
      }
  
      public MailerEnhancer classInfoHolder(MailerClassMetaInfoHolder holder) {
          classInfoHolder = holder;
          predicate(_F.isMailer(holder));
          return this;
      }
  
      @Override
      public void visit(int version, int access, String name, String signature, String superName, String[] interfaces) {
          super.visit(version, access, name, signature, superName, interfaces);
          className = Type.getObjectType(name).getClassName();
      }
  
      @Override
      public MethodVisitor visitMethod(int access, String name, String desc, String signature, String[] exceptions) {
          MethodVisitor mv = super.visitMethod(access, name, desc, signature, exceptions);
          SenderMethodMetaInfo info = methodInfo(name, access);
          if (null == info) {
              return mv;
          }
          logger.debug(">>>About to enhance mailer method: %s", name);
          return new SenderEnhancer(mv, info, access, name, desc, signature, exceptions);
      }
  
      private SenderMethodMetaInfo methodInfo(String name, int access) {
          if (isPublic(access) && !isConstructor(name)) {
              MailerClassMetaInfo ccInfo = classInfoHolder.mailerClassMetaInfo(className);
              if (null == ccInfo) {
                  return null;
              }
              SenderMethodMetaInfo info = ccInfo.sender(name);
              if (null != info) {
                  return info;
              }
              return ccInfo.sender(name);
          } else {
              return null;
          }
      }
  
      private boolean isTargetMethod(String name, int access) {
          return isPublic(access) && !isConstructor(name) && methodInfo(name, access) != null;
      }
  
      private enum _F {
          ;
  
          private static final $.Predicate<String> isMailer(final MailerClassMetaInfoHolder infoSrc) {
              return new $.Predicate<String>() {
                  @Override
                  public boolean test(String s) {
                      return infoSrc.mailerClassMetaInfo(s) != null;
                  }
              };
          }
      }
  }
  