package com.atlassian.sal.spring.component;
   
   import com.atlassian.sal.spi.HostContextAccessor;
   import org.slf4j.Logger;
   import org.slf4j.LoggerFactory;
   import org.springframework.beans.BeansException;
   import org.springframework.beans.factory.config.ConfigurableListableBeanFactory;
   import org.springframework.beans.factory.support.DefaultListableBeanFactory;
   import org.springframework.context.ApplicationContext;
  import org.springframework.context.ApplicationContextAware;
  import org.springframework.context.support.AbstractApplicationContext;
  import org.springframework.transaction.PlatformTransactionManager;
  import org.springframework.transaction.TransactionDefinition;
  import org.springframework.transaction.support.DefaultTransactionDefinition;
  import org.springframework.transaction.support.TransactionCallback;
  
  import java.util.HashMap;
  import java.util.Map;
  
  /**
   * Implements the host context accessor for Spring environments
   */
  public class SpringHostContextAccessor implements HostContextAccessor, ApplicationContextAware {
      private ApplicationContext applicationContext;
      private final PlatformTransactionManager transactionManager;
      private static final Logger log = LoggerFactory.getLogger(SpringHostContextAccessor.class);
  
      public SpringHostContextAccessor(final PlatformTransactionManager transactionManager) {
          this.transactionManager = transactionManager;
      }
  
      @SuppressWarnings("unchecked")
      public <T> Map<String, T> getComponentsOfType(final Class<T> iface) {
          try {
              return applicationContext.getBeansOfType(iface);
          } catch (final RuntimeException ex) {
              // This exception will start occuring after removing bean from the context (eg: disabling plugin)
              // until next restart of Confluence. See https://studio.atlassian.com/browse/JST-509
              log.debug("Can't get beans", ex);
              final Map<String, T> results = new HashMap<>();
              if (applicationContext instanceof AbstractApplicationContext) {
                  final AbstractApplicationContext abstractApplicationContext = (AbstractApplicationContext) applicationContext;
                  final ConfigurableListableBeanFactory beanFactory = abstractApplicationContext.getBeanFactory();
                  if (beanFactory instanceof DefaultListableBeanFactory) {
                      final DefaultListableBeanFactory defaultListableBeanFactory = (DefaultListableBeanFactory) beanFactory;
                      final String[] beanDefinitionNames = defaultListableBeanFactory.getBeanDefinitionNames();
                      for (final String beanName : beanDefinitionNames) {
                          try {
                              final Object bean = defaultListableBeanFactory.getBean(beanName);
                              if (bean != null && iface.isAssignableFrom(bean.getClass())) {
                                  results.put(beanName, (T) bean);
                              }
                          } catch (final BeansException e) {
                              // ignore
                          }
                      }
                  }
              }
              return results;
          }
  
  
      }
  
      public Object doInTransaction(final HostTransactionCallback callback) {
          final org.springframework.transaction.support.TransactionTemplate txTemplate =
                  new org.springframework.transaction.support.TransactionTemplate(transactionManager, getTransactionDefinition());
          return txTemplate.execute((TransactionCallback) transactionStatus -> {
              try {
                  return callback.doInTransaction();
              } catch (final RuntimeException e) {
                  //rollback if something weird happened.
                  transactionStatus.setRollbackOnly();
                  throw e;
              }
          });
      }
  
      public void setApplicationContext(final ApplicationContext applicationContext) throws BeansException {
          this.applicationContext = applicationContext;
      }
  
      protected DefaultTransactionDefinition getTransactionDefinition() {
          final DefaultTransactionDefinition def = new DefaultTransactionDefinition();
          def.setName("PluginReadWriteTx");
          def.setPropagationBehavior(TransactionDefinition.PROPAGATION_REQUIRED);
          def.setReadOnly(false);
          return def;
      }
  
  
  }