/*
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.griffin.measure.context

import scala.collection.mutable.{Set => MutableSet}

import org.apache.spark.sql._

import org.apache.griffin.measure.Loggable


/**
  * register table name
  */
trait TableRegister extends Loggable with Serializable {

  protected val tables: MutableSet[String] = MutableSet()

  def registerTable(name: String): Unit = {
    tables += name
  }

  def existsTable(name: String): Boolean = {
    tables.exists(_.equals(name))
  }

  def unregisterTable(name: String): Unit = {
    if (existsTable(name)) tables -= name
  }
  def unregisterAllTables(): Unit = {
    tables.clear
  }

  def getTables(): Set[String] = {
    tables.toSet
  }

}

/**
  * register table name when building dq job
  */
case class CompileTableRegister() extends TableRegister {}

/**
  * register table name and create temp view during calculation
  */
case class RunTimeTableRegister(@transient sqlContext: SQLContext) extends TableRegister {

  def registerTable(name: String, df: DataFrame): Unit = {
    registerTable(name)
    df.createOrReplaceTempView(name)
  }

  override def unregisterTable(name: String): Unit = {
    if (existsTable(name)) {
      sqlContext.dropTempTable(name)
      tables -= name
    }
  }
  override def unregisterAllTables(): Unit = {
    val uts = getTables
    uts.foreach(t => sqlContext.dropTempTable(t))
    tables.clear
  }

}