/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you 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.
 */
package org.apache.phoenix.rpc;

import static org.apache.phoenix.util.TestUtil.DEFAULT_SCHEMA_NAME;
import static org.junit.Assert.assertTrue;
import static org.mockito.ArgumentMatchers.anyLong;
import static org.mockito.ArgumentMatchers.eq;
import static org.mockito.Mockito.isNull;
import static org.mockito.Mockito.reset;
import static org.mockito.Mockito.times;
import static org.mockito.Mockito.verify;

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.Properties;
import org.apache.phoenix.end2end.ParallelStatsDisabledIT;
import org.apache.phoenix.end2end.ParallelStatsDisabledTest;
import org.apache.phoenix.query.ConnectionQueryServices;
import org.apache.phoenix.query.QueryConstants;
import org.apache.phoenix.query.QueryServices;
import org.apache.phoenix.schema.PName;
import org.apache.phoenix.schema.types.PVarchar;
import org.apache.phoenix.util.SchemaUtil;
import org.apache.phoenix.util.ValidateLastDDLTimestampUtil;
import org.junit.AfterClass;
import org.junit.Test;
import org.junit.experimental.categories.Category;
import org.mockito.Mockito;

/**
 * Tests for connection level 'Update Cache Frequency' property. The tests verify that the 'Update
 * Cache Frequency' is honored in the following precedence order for SELECTs and UPSERTs:
 * Table-level property > Connection-level property > Default value
 */
@Category(ParallelStatsDisabledTest.class)
public class UpdateCacheConnectionLevelPropIT extends ParallelStatsDisabledIT {

  private static Connection conn1;
  private static Connection conn2;
  private static ConnectionQueryServices spyForConn2;
  private boolean isLastDDLTimestampValidationEnabled =
    ValidateLastDDLTimestampUtil.getValidateLastDdlTimestampEnabled(config);

  @AfterClass
  public static synchronized void freeResources() {
    try {
      conn1.close();
      conn2.close();
    } catch (Exception e) {
      /* ignored */
    }
  }

  /**
   * Test 'Update Cache Frequency' property when it is set at connection-level only, and not at
   * table-level.
   */
  @Test
  public void testWithConnLevelUCFNoTableLevelUCF() throws Exception {
    final long connUpdateCacheFrequency = 1000;
    String fullTableName =
      DEFAULT_SCHEMA_NAME + QueryConstants.NAME_SEPARATOR + generateUniqueName();

    setUpTableAndConnections(fullTableName, null, String.valueOf(connUpdateCacheFrequency));

    // There should only be no call to getTable() for fetching the table's metadata since
    // it will be in the CQSI cache
    int numExecutions = 2;
    int numExpectedGetTableCalls = 0;
    verifyExpectedGetTableCalls(fullTableName, numExecutions, numExpectedGetTableCalls);

    // Wait for a period of 'connUpdateCacheFrequency' and verify that there was one new call to
    // getTable() for fetching the table's metadata
    Thread.sleep(connUpdateCacheFrequency);
    numExpectedGetTableCalls = 1;
    verifyExpectedGetTableCalls(fullTableName, numExecutions, numExpectedGetTableCalls);
  }

  /**
   * Test 'Update Cache Frequency' property when it is set at table-level only, and not at
   * connection-level.
   */
  @Test
  public void testWithTableLevelUCFNoConnLevelUCF() throws Exception {
    final long tableUpdateCacheFrequency = 1000;
    String fullTableName =
      DEFAULT_SCHEMA_NAME + QueryConstants.NAME_SEPARATOR + generateUniqueName();

    // There should only be no call to getTable() for fetching the table's metadata since
    // it will be in the CQSI cache
    int numExecutions = 2;
    int numExpectedGetTableCalls = 0;
    setUpTableAndConnections(fullTableName, String.valueOf(tableUpdateCacheFrequency), null);
    verifyExpectedGetTableCalls(fullTableName, numExecutions, numExpectedGetTableCalls);

    // Wait for a period of 'tableUpdateCacheFrequency' and verify that there was one new call
    // to getTable() for fetching the table's metadata
    Thread.sleep(tableUpdateCacheFrequency);
    numExpectedGetTableCalls = 1;
    verifyExpectedGetTableCalls(fullTableName, numExecutions, numExpectedGetTableCalls);
  }

  /**
   * Test 'Update Cache Frequency' property when it is not set at both table-level and
   * connection-level.
   */
  @Test
  public void testWithNoConnAndTableLevelUCF() throws Exception {
    String fullTableName =
      DEFAULT_SCHEMA_NAME + QueryConstants.NAME_SEPARATOR + generateUniqueName();

    // This is the default behavior (i.e. always fetch the latest metadata of the table) when
    // both connection and table level properties are not set
    int numExecutions = 2;
    int numExpectedGetTableCalls = 4; // 2 for SELECTs, and 2 for UPSERTs

    // there will be no getTable calls if we are validating last_ddl_timestamps
    // and schema has not changed.
    if (isLastDDLTimestampValidationEnabled) {
      numExpectedGetTableCalls = 0;
    }
    setUpTableAndConnections(fullTableName, null, null);
    verifyExpectedGetTableCalls(fullTableName, numExecutions, numExpectedGetTableCalls);
  }

  /**
   * Test 'Update Cache Frequency' property when it is set at both table-level and connection-level.
   */
  @Test
  public void testWithBothConnAndTableLevelUCF() throws Exception {
    // Set table level property to a much higher value than the connection level property
    final long tableUpdateCacheFrequency = 5000;
    final long connUpdateCacheFrequency = 1000;
    String fullTableName =
      DEFAULT_SCHEMA_NAME + QueryConstants.NAME_SEPARATOR + generateUniqueName();

    // There should only be no call to getTable() for fetching the table's metadata since
    // it will be in the CQSI cache
    int numExecutions = 2;
    int numExpectedGetTableCalls = 0;
    setUpTableAndConnections(fullTableName, String.valueOf(tableUpdateCacheFrequency),
      String.valueOf(connUpdateCacheFrequency));
    verifyExpectedGetTableCalls(fullTableName, numExecutions, numExpectedGetTableCalls);

    // Wait for a period of 'connUpdateCacheFrequency' and verify that there were no new calls
    // to getTable() as the table level UCF should come in to effect
    Thread.sleep(connUpdateCacheFrequency);
    numExpectedGetTableCalls = 0;
    verifyExpectedGetTableCalls(fullTableName, numExecutions, numExpectedGetTableCalls);

    // Extend the wait to a period of 'tableUpdateCacheFrequency' and verify that there was one
    // new call to getTable() for fetching the table's metadata
    Thread.sleep(tableUpdateCacheFrequency - connUpdateCacheFrequency);
    numExpectedGetTableCalls = 1;
    verifyExpectedGetTableCalls(fullTableName, numExecutions, numExpectedGetTableCalls);
  }

  /**
   * Helper method that sets up the connections and creates the table to be tested.
   * @param fullTableName             The table's full name
   * @param tableUpdateCacheFrequency If not null, the table-level value to be set for 'Update Cache
   *                                  Frequency'
   * @param connUpdateCacheFrequency  If not null, the connection-level value to be set for 'Update
   *                                  Cache Frequency'
   */
  private static void setUpTableAndConnections(String fullTableName,
    String tableUpdateCacheFrequency, String connUpdateCacheFrequency) throws SQLException {
    // Create two connections - a connection that we'll use to create the table and the second
    // one that we will spy on and use to query the table.
    Properties props = new Properties();
    conn1 = DriverManager.getConnection(getUrl(), props);
    conn1.setAutoCommit(true);

    if (connUpdateCacheFrequency != null) {
      props.put(QueryServices.DEFAULT_UPDATE_CACHE_FREQUENCY_ATRRIB, connUpdateCacheFrequency);
    }

    // use a spied ConnectionQueryServices so we can verify calls to getTable()
    spyForConn2 = Mockito.spy(driver.getConnectionQueryServices(getUrl(), props));
    conn2 = spyForConn2.connect(getUrl(), props);
    conn2.setAutoCommit(true);

    String createTableQuery =
      "CREATE TABLE " + fullTableName + " (k UNSIGNED_DOUBLE NOT NULL PRIMARY KEY, "
        + "v1 UNSIGNED_DOUBLE, v2 UNSIGNED_DOUBLE, v3 UNSIGNED_DOUBLE)";

    if (tableUpdateCacheFrequency != null) {
      createTableQuery += " UPDATE_CACHE_FREQUENCY = " + tableUpdateCacheFrequency;
    }

    // Create the table over first connection
    try (Statement stmt = conn1.createStatement()) {
      stmt.execute(createTableQuery);
      stmt.execute("UPSERT INTO " + fullTableName + " VALUES (1, 2, 3, 4)");
    }
    conn1.commit();
  }

  /**
   * Helper method that executes a select and upsert query on the table for \p numSelectExecutions
   * times and verifies that \p numExpectedGetTableCalls were made to getTable() for the table. Also
   * resets the spy object for conn2 before returning.
   * @param fullTableName            The table's full name
   * @param numExecutions            Number of times a select+upsert should be executed on the table
   * @param numExpectedGetTableCalls Number of expected calls to getTable()
   */
  private static void verifyExpectedGetTableCalls(String fullTableName, int numExecutions,
    int numExpectedGetTableCalls) throws SQLException {
    String tableName = SchemaUtil.getTableNameFromFullName(fullTableName);
    String schemaName = SchemaUtil.getSchemaNameFromFullName(fullTableName);
    String selectFromTableQuery = "SELECT k, v1, v2, v3 FROM " + fullTableName;

    for (int i = 0; i < numExecutions; i++) {
      // Query the table over the spied connection that has update cache frequency set
      try (Statement stmt = conn2.createStatement();
        ResultSet rs = stmt.executeQuery(selectFromTableQuery)) {
        assertTrue(rs.next());
        stmt.execute("UPSERT INTO " + fullTableName + " VALUES (1, 2, 3, 4)");
      }
    }

    // Verify number of calls to getTable() for our table
    verify(spyForConn2, times(numExpectedGetTableCalls)).getTable((PName) isNull(),
      eq(PVarchar.INSTANCE.toBytes(schemaName)), eq(PVarchar.INSTANCE.toBytes(tableName)),
      anyLong(), anyLong());
    reset(spyForConn2);
  }
}
