/*
 * Copyright (c) MuleSoft, Inc.  All rights reserved.  http://www.mulesoft.com
 * The software in this package is published under the terms of the CPAL v1.0
 * license, a copy of which has been included with this distribution in the
 * LICENSE.txt file.
 */
package org.mule.tck;

import static org.junit.Assert.assertEquals;
import static org.junit.Assert.assertFalse;
import static org.junit.Assert.assertNotNull;
import static org.junit.Assert.assertNull;
import static org.junit.Assert.assertTrue;
import static org.junit.Assert.fail;

import org.mule.runtime.core.api.execution.ExecutionCallback;
import org.mule.runtime.core.api.execution.ExecutionTemplate;
import org.mule.runtime.core.api.transaction.TransactionConfig;
import org.mule.runtime.core.api.transaction.TransactionManagerFactory;
import org.mule.runtime.core.api.execution.TransactionalExecutionTemplate;
import org.mule.tck.junit4.AbstractMuleContextTestCase;
import org.mule.runtime.core.api.transaction.MuleTransactionConfig;
import org.mule.runtime.core.api.transaction.xa.XaTransaction;
import org.mule.runtime.core.api.transaction.xa.XaTransactionFactory;

import javax.transaction.Status;
import javax.transaction.Transaction;
import javax.transaction.TransactionManager;

import org.junit.Test;

/**
 * Validate certain expectations when working with JTA API. It is called to catch discrepancies in TM implementations and alert
 * early. Subclasses are supposed to plug in specific transaction managers for tests.
 */
public abstract class AbstractTxThreadAssociationTestCase extends AbstractMuleContextTestCase {

  /* To allow access from the dead TX threads we spawn. */
  private TransactionManager tm;
  protected static final int TRANSACTION_TIMEOUT_SECONDS = 3;

  @Override
  protected void doSetUp() throws Exception {
    super.doSetUp();
    TransactionManagerFactory factory = getTransactionManagerFactory();
    tm = factory.create(muleContext.getConfiguration());
    assertNotNull("Transaction Manager should be available.", tm);
    assertNull("There should be no current transaction associated.", tm.getTransaction());
  }

  @Test
  public void testTxHandleCommitKeepsThreadAssociation() throws Exception {
    // don't wait for ages, has to be set before TX is begun
    tm.setTransactionTimeout(TRANSACTION_TIMEOUT_SECONDS);
    tm.begin();

    Transaction tx = tm.getTransaction();
    assertNotNull("Transaction should have started.", tx);
    assertEquals("TX should have been active", Status.STATUS_ACTIVE, tx.getStatus());

    tx.commit();

    tx = tm.getTransaction();
    assertNotNull("Committing via TX handle should NOT disassociated TX from the current thread.", tx);
    assertEquals("TX status should have been COMMITTED.", Status.STATUS_COMMITTED, tx.getStatus());

    // Remove the TX-thread association. The only public API to achieve it is suspend(),
    // technically we never resume the same transaction (TX forget).
    Transaction suspended = tm.suspend();
    assertTrue("Wrong TX suspended?.", suspended.equals(tx));
    assertNull("TX should've been disassociated from the thread.", tm.getTransaction());

    // should be no-op and never fail
    tm.resume(null);

    // ensure we don't have any TX-Thread association lurking around a main thread
    assertNull(tm.getTransaction());
  }

  @Test
  public void testTxManagerCommitDissassociatesThread() throws Exception {
    // don't wait for ages, has to be set before TX is begun
    tm.setTransactionTimeout(TRANSACTION_TIMEOUT_SECONDS);
    tm.begin();

    Transaction tx = tm.getTransaction();
    assertNotNull("Transaction should have started.", tx);
    assertEquals("TX should have been active", Status.STATUS_ACTIVE, tx.getStatus());

    tm.commit();

    assertNull("Committing via TX Manager should have disassociated TX from the current thread.", tm.getTransaction());
  }

  @Test
  public void testTxManagerRollbackDissassociatesThread() throws Exception {
    // don't wait for ages, has to be set before TX is begun
    tm.setTransactionTimeout(TRANSACTION_TIMEOUT_SECONDS);
    tm.begin();

    Transaction tx = tm.getTransaction();
    assertNotNull("Transaction should have started.", tx);
    assertEquals("TX should have been active", Status.STATUS_ACTIVE, tx.getStatus());

    tm.rollback();

    assertNull("Committing via TX Manager should have disassociated TX from the current thread.", tm.getTransaction());
  }

  /**
   * AlwaysBegin action suspends current transaction and begins a new one.
   *
   * @throws Exception if any error
   */
  @Test
  public void testAlwaysBeginXaTransactionSuspendResume() throws Exception {
    muleContext.setTransactionManager(tm);
    assertNull("There should be no current transaction associated.", tm.getTransaction());

    // don't wait for ages, has to be set before TX is begun
    tm.setTransactionTimeout(TRANSACTION_TIMEOUT_SECONDS);

    // this is one component with a TX always begin
    TransactionConfig config = new MuleTransactionConfig(TransactionConfig.ACTION_ALWAYS_BEGIN);
    config.setFactory(new XaTransactionFactory());
    ExecutionTemplate<Void> executionTemplate =
        TransactionalExecutionTemplate.createTransactionalExecutionTemplate(muleContext, config);

    // and the callee component which should begin new transaction, current must be suspended
    final TransactionConfig nestedConfig = new MuleTransactionConfig(TransactionConfig.ACTION_ALWAYS_BEGIN);
    nestedConfig.setFactory(new XaTransactionFactory());

    // start the call chain
    executionTemplate.execute(new ExecutionCallback<Void>() {

      @Override
      public Void process() throws Exception {
        // the callee executes within its own TX template, but uses the same global XA transaction,
        // bound to the current thread of execution via a ThreadLocal
        ExecutionTemplate<Void> innerExecutionTemplate =
            TransactionalExecutionTemplate.createTransactionalExecutionTemplate(muleContext, nestedConfig);
        final Transaction firstTx = tm.getTransaction();
        assertNotNull(firstTx);
        assertEquals(firstTx.getStatus(), Status.STATUS_ACTIVE);
        return innerExecutionTemplate.execute(new ExecutionCallback<Void>() {

          @Override
          public Void process() throws Exception {
            Transaction secondTx = tm.getTransaction();
            assertNotNull(secondTx);
            assertEquals(firstTx.getStatus(), Status.STATUS_ACTIVE);
            assertEquals(secondTx.getStatus(), Status.STATUS_ACTIVE);
            try {
              tm.resume(firstTx);
              fail("Second transaction must be active");
            } catch (java.lang.IllegalStateException e) {
              // expected

              // Thrown if the thread is already associated with another transaction.
              // Second tx is associated with the current thread
            }
            try {
              Transaction currentTx = tm.suspend();
              assertTrue(currentTx.equals(secondTx));
              tm.resume(firstTx);
              assertEquals(firstTx, tm.getTransaction());
              assertEquals(firstTx.getStatus(), Status.STATUS_ACTIVE);
              assertEquals(secondTx.getStatus(), Status.STATUS_ACTIVE);
              Transaction a = tm.suspend();
              assertTrue(a.equals(firstTx));
              tm.resume(secondTx);
            } catch (Exception e) {
              fail("Error: " + e);
            }

            // do not care about the return really
            return null;
          }
        });
      }
    });
    assertNull("Committing via TX Manager should have disassociated TX from the current thread.", tm.getTransaction());
  }

  /**
   * NONE action suspends current transaction and begins a new one.
   *
   * @throws Exception if any error
   */
  @Test
  public void testNoneXaTransactionSuspendResume() throws Exception {
    muleContext.setTransactionManager(tm);
    assertNull("There should be no current transaction associated.", tm.getTransaction());

    // don't wait for ages, has to be set before TX is begun
    tm.setTransactionTimeout(TRANSACTION_TIMEOUT_SECONDS);

    // this is one component with a TX always begin
    TransactionConfig config = new MuleTransactionConfig(TransactionConfig.ACTION_ALWAYS_BEGIN);
    config.setFactory(new XaTransactionFactory());
    ExecutionTemplate<Void> executionTemplate =
        TransactionalExecutionTemplate.createTransactionalExecutionTemplate(muleContext, config);

    // and the callee component which should begin new transaction, current must be suspended
    final TransactionConfig nestedConfig = new MuleTransactionConfig(TransactionConfig.ACTION_NONE);
    nestedConfig.setFactory(new XaTransactionFactory());

    // start the call chain
    executionTemplate.execute(new ExecutionCallback<Void>() {

      @Override
      public Void process() throws Exception {
        // the callee executes within its own TX template, but uses the same global XA transaction,
        // bound to the current thread of execution via a ThreadLocal
        ExecutionTemplate<Void> nestedExecutionTemplate =
            TransactionalExecutionTemplate.createTransactionalExecutionTemplate(muleContext, nestedConfig);
        final Transaction firstTx = tm.getTransaction();
        assertNotNull(firstTx);
        assertEquals(firstTx.getStatus(), Status.STATUS_ACTIVE);
        return nestedExecutionTemplate.execute(new ExecutionCallback<Void>() {

          @Override
          public Void process() throws Exception {
            Transaction secondTx = tm.getTransaction();
            assertNull(secondTx);
            assertEquals(firstTx.getStatus(), Status.STATUS_ACTIVE);
            try {
              tm.resume(firstTx);
              assertEquals(firstTx, tm.getTransaction());
              assertEquals(firstTx.getStatus(), Status.STATUS_ACTIVE);
              Transaction a = tm.suspend();
              assertTrue(a.equals(firstTx));
            } catch (Exception e) {
              fail("Error: " + e);
            }

            // do not care about the return really
            return null;
          }
        });
      }
    });
    assertNull("Committing via TX Manager should have disassociated TX from the current thread.", tm.getTransaction());
  }

  /**
   * This is a former XaTransactionTestCase.
   *
   * @throws Exception in case of any error
   */
  @Test
  public void testXaTransactionTermination() throws Exception {
    muleContext.setTransactionManager(tm);
    assertNull("There should be no current transaction associated.", tm.getTransaction());

    // don't wait for ages, has to be set before TX is begun
    tm.setTransactionTimeout(TRANSACTION_TIMEOUT_SECONDS);

    XaTransaction muleTx = new XaTransaction(muleContext);
    assertFalse(muleTx.isBegun());
    assertEquals(Status.STATUS_NO_TRANSACTION, muleTx.getStatus());
    muleTx.begin();

    assertTrue(muleTx.isBegun());

    muleTx.commit();

    Transaction jtaTx = tm.getTransaction();
    assertNull("Committing via TX Manager should have disassociated TX from the current thread.", jtaTx);
    assertEquals(Status.STATUS_NO_TRANSACTION, muleTx.getStatus());
  }

  /**
   * This is a former TransactionTemplateTestCase. http://mule.mulesoft.org/jira/browse/MULE-1494
   *
   * @throws Exception in case of any error
   */
  @Test
  public void testNoNestedTxStarted() throws Exception {
    muleContext.setTransactionManager(tm);
    assertNull("There should be no current transaction associated.", tm.getTransaction());

    // don't wait for ages, has to be set before TX is begun
    tm.setTransactionTimeout(TRANSACTION_TIMEOUT_SECONDS);

    // this is one service with a TX always begin
    TransactionConfig config = new MuleTransactionConfig(TransactionConfig.ACTION_ALWAYS_BEGIN);
    config.setFactory(new XaTransactionFactory());
    ExecutionTemplate<Void> executionTemplate =
        TransactionalExecutionTemplate.createTransactionalExecutionTemplate(muleContext, config);

    // and the callee service which should join the current XA transaction, not begin a nested one
    final TransactionConfig nestedConfig = new MuleTransactionConfig(TransactionConfig.ACTION_BEGIN_OR_JOIN);
    nestedConfig.setFactory(new XaTransactionFactory());

    // start the call chain
    executionTemplate.execute(new ExecutionCallback<Void>() {

      @Override
      public Void process() throws Exception {
        // the callee executes within its own TX template, but uses the same global XA transaction,
        // bound to the current thread of execution via a ThreadLocal
        ExecutionTemplate<Void> nestedExecutionTemplate =
            TransactionalExecutionTemplate.createTransactionalExecutionTemplate(muleContext, nestedConfig);
        return nestedExecutionTemplate.execute(new ExecutionCallback<Void>() {

          @Override
          public Void process() throws Exception {
            // do not care about the return really
            return null;
          }
        });
      }
    });
  }


  protected TransactionManager getTransactionManager() {
    return tm;
  }

  protected abstract TransactionManagerFactory getTransactionManagerFactory();

}
