/**
 * 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.
 **/

#include "query_optimizer/rules/CollapseProject.hpp"

#include <memory>

#include "query_optimizer/expressions/Alias.hpp"
#include "query_optimizer/expressions/AttributeReference.hpp"
#include "query_optimizer/expressions/BinaryExpression.hpp"
#include "query_optimizer/expressions/Expression.hpp"
#include "query_optimizer/expressions/ExpressionUtil.hpp"
#include "query_optimizer/expressions/NamedExpression.hpp"
#include "query_optimizer/expressions/ScalarLiteral.hpp"
#include "query_optimizer/logical/Project.hpp"
#include "query_optimizer/logical/TableReference.hpp"
#include "query_optimizer/rules/tests/LogicalRuleTest.hpp"
#include "query_optimizer/rules/tests/RuleTest.hpp"
#include "types/operations/binary_operations/BinaryOperation.hpp"
#include "types/operations/binary_operations/BinaryOperationFactory.hpp"
#include "types/operations/binary_operations/BinaryOperationID.hpp"
#include "utility/Macros.hpp"

#include "glog/logging.h"
#include "gtest/gtest.h"

namespace quickstep {
namespace optimizer {

namespace E = ::quickstep::optimizer::expressions;
namespace L = ::quickstep::optimizer::logical;

class CollapseProjectTest : public LogicalRuleTest {
 protected:
  CollapseProjectTest() {}

  ~CollapseProjectTest() override {}

  void setupRule(std::unique_ptr<Rule<L::Logical>> *rule) override {
    rule->reset(new CollapseProject());
  }

 private:
  DISALLOW_COPY_AND_ASSIGN(CollapseProjectTest);
};

TEST_F(CollapseProjectTest, Tests) {
  // Merge three-level Projects into one.
  const E::ExpressionPtr alias_0_add_literal_0 = E::BinaryExpression::Create(
      BinaryOperationFactory::GetBinaryOperation(BinaryOperationID::kAdd),
      E::ToRef(alias_0_),
      literal_0_);
  const E::AliasPtr alias_on_alias_0_add_literal_0 = createAlias(
      alias_0_add_literal_0,
      "alias_alias_0_add_literal_0" /* attribute_name */,
      "select_test_relation" /* relation_name */);
  const L::ProjectPtr second_level_project = L::Project::Create(
      logical_project_0_ /* first level project */,
      {alias_on_alias_0_add_literal_0} /* project_expressions */);
  const E::AliasPtr alias_on_alias_on_alias_0_add_literal_0 = createAlias(
      E::ToRef(alias_on_alias_0_add_literal_0),
      "alias_on_alias_on_alias_0_add_literal_0" /* attribute_name */,
      "select_test_relation" /* relation_name */);
  // The top level project.
  input_ = L::Project::Create(second_level_project,
                              {alias_on_alias_on_alias_0_add_literal_0});

  const E::ExpressionPtr alias_0_add_literal_0_after_pullup =
      alias_0_add_literal_0->copyWithNewChildren(
          {alias_0_->expression(), literal_0_} /* new_children */);
  const E::AliasPtr alias_on_alias_on_alias_0_add_literal_0_after_pullup =
      std::static_pointer_cast<const E::Alias>(
          alias_on_alias_on_alias_0_add_literal_0->copyWithNewChildren(
              {alias_0_add_literal_0_after_pullup} /* new_children */));
  expect_output_ = L::Project::Create(
      logical_table_reference_0_,
      {alias_on_alias_on_alias_0_add_literal_0_after_pullup} /* project_expressions */);
  APPLY_RULE_AND_CHECK_OUTPUT();
}

}  // namespace optimizer
}  // namespace quickstep