/**
 * 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 <cstddef>
#include <cstdint>
#include <memory>
#include <string>
#include <vector>

#include "catalog/CatalogTypedefs.hpp"
#include "expressions/aggregation/AggregateFunction.hpp"
#include "expressions/aggregation/AggregateFunctionFactory.hpp"
#include "expressions/aggregation/AggregationHandle.hpp"
#include "expressions/aggregation/AggregationHandleCount.hpp"
#include "expressions/aggregation/AggregationID.hpp"
#include "storage/AggregationOperationState.hpp"
#include "storage/PackedPayloadHashTable.hpp"
#include "storage/StorageManager.hpp"
#include "storage/ValueAccessorMultiplexer.hpp"
#include "types/CharType.hpp"
#include "types/DoubleType.hpp"
#include "types/FloatType.hpp"
#include "types/IntType.hpp"
#include "types/LongType.hpp"
#include "types/Type.hpp"
#include "types/TypeFactory.hpp"
#include "types/TypeID.hpp"
#include "types/TypedValue.hpp"
#include "types/VarCharType.hpp"
#include "types/containers/ColumnVector.hpp"
#include "types/containers/ColumnVectorsValueAccessor.hpp"

#include "gtest/gtest.h"

namespace quickstep {

class AggregationHandleCountTest : public ::testing::Test {
 protected:
  const Type &dummy_type = TypeFactory::GetType(kInt);

  void iterateHandleNullary(AggregationState *state) {
    static_cast<const AggregationHandleCount<true, false> &>(
        *aggregation_handle_count_)
        .iterateNullaryInl(static_cast<AggregationStateCount *>(state));
  }

  // Helper method that calls AggregationHandleCount::iterateUnaryInl() to
  // aggregate 'value' into '*state'.
  void iterateHandle(AggregationState *state, const TypedValue &value) {
    static_cast<const AggregationHandleCount<false, true> &>(
        *aggregation_handle_count_)
        .iterateUnaryInl(static_cast<AggregationStateCount *>(state), value);
  }

  void initializeHandle(const Type *argument_type) {
    if (argument_type == nullptr) {
      aggregation_handle_count_.reset(
          AggregateFunctionFactory::Get(AggregationID::kCount)
              .createHandle(std::vector<const Type *>()));
    } else {
      aggregation_handle_count_.reset(
          AggregateFunctionFactory::Get(AggregationID::kCount)
              .createHandle(std::vector<const Type *>(1, argument_type)));
    }
    aggregation_handle_count_state_.reset(
        aggregation_handle_count_->createInitialState());
  }

  static bool ApplyToTypesTest(TypeID typeID) {
    const Type &type =
        (typeID == kChar || typeID == kVarChar)
            ? TypeFactory::GetType(typeID, static_cast<std::size_t>(10))
            : TypeFactory::GetType(typeID);

    return AggregateFunctionFactory::Get(AggregationID::kCount)
        .canApplyToTypes(std::vector<const Type *>(1, &type));
  }

  static bool ResultTypeForArgumentTypeTest(TypeID input_type_id,
                                            TypeID output_type_id) {
    const Type *result_type =
        AggregateFunctionFactory::Get(AggregationID::kCount)
            .resultTypeForArgumentTypes(std::vector<const Type *>(
                1, &TypeFactory::GetType(input_type_id)));
    return (result_type->getTypeID() == output_type_id);
  }

  static void CheckCountValue(std::int64_t expected,
                              const AggregationHandle &handle,
                              const AggregationState &state) {
    EXPECT_EQ(expected, handle.finalize(state).getLiteral<std::int64_t>());
  }

  static void CheckCountValue(std::int64_t expected, const TypedValue &value) {
    EXPECT_EQ(expected, value.getLiteral<std::int64_t>());
  }

  void checkAggregationCountNullary(int test_count) {
    initializeHandle(nullptr);
    CheckCountValue(
        0, *aggregation_handle_count_, *aggregation_handle_count_state_);

    for (int i = 0; i < test_count; ++i) {
      iterateHandleNullary(aggregation_handle_count_state_.get());
    }
    CheckCountValue(test_count,
                    *aggregation_handle_count_,
                    *aggregation_handle_count_state_);

    // Test mergeStates.
    std::unique_ptr<AggregationState> merge_state(
        aggregation_handle_count_->createInitialState());
    aggregation_handle_count_->mergeStates(
        *merge_state, aggregation_handle_count_state_.get());

    for (int i = 0; i < test_count; ++i) {
      iterateHandleNullary(merge_state.get());
    }

    aggregation_handle_count_->mergeStates(
        *merge_state, aggregation_handle_count_state_.get());
    CheckCountValue(2 * test_count,
                    *aggregation_handle_count_,
                    *aggregation_handle_count_state_);
  }

  void checkAggregationCountNullaryAccumulate(int test_count) {
    initializeHandle(nullptr);

    std::unique_ptr<AggregationState> accumulated_state(
        aggregation_handle_count_->accumulateNullary(test_count));

    // Test the state generated directly by accumulateNullary(), and also test
    // after merging back.
    CheckCountValue(test_count, *aggregation_handle_count_, *accumulated_state);

    aggregation_handle_count_->mergeStates(
        *accumulated_state, aggregation_handle_count_state_.get());
    CheckCountValue(test_count,
                    *aggregation_handle_count_,
                    *aggregation_handle_count_state_);
  }

  template <typename NumericType>
  void checkAggregationCountNumeric(int test_count) {
    const NumericType &type = NumericType::Instance(true);
    initializeHandle(&type);
    CheckCountValue(
        0, *aggregation_handle_count_, *aggregation_handle_count_state_);

    typename NumericType::cpptype val = 0;
    int count = 0;

    iterateHandle(aggregation_handle_count_state_.get(), type.makeNullValue());
    for (int i = 0; i < test_count; ++i) {
      iterateHandle(aggregation_handle_count_state_.get(),
                    type.makeValue(&val));
      ++count;
    }
    iterateHandle(aggregation_handle_count_state_.get(), type.makeNullValue());
    CheckCountValue(
        count, *aggregation_handle_count_, *aggregation_handle_count_state_);

    // Test mergeStates.
    std::unique_ptr<AggregationState> merge_state(
        aggregation_handle_count_->createInitialState());
    aggregation_handle_count_->mergeStates(
        *merge_state, aggregation_handle_count_state_.get());

    iterateHandle(merge_state.get(), type.makeNullValue());
    for (int i = 0; i < test_count; ++i) {
      iterateHandle(merge_state.get(), type.makeValue(&val));
      ++count;
    }
    iterateHandle(merge_state.get(), type.makeNullValue());

    aggregation_handle_count_->mergeStates(
        *merge_state, aggregation_handle_count_state_.get());
    CheckCountValue(
        count, *aggregation_handle_count_, *aggregation_handle_count_state_);
  }

  template <typename NumericType>
  ColumnVector* createColumnVectorNumeric(const Type &type, int test_count) {
    NativeColumnVector *column = new NativeColumnVector(type, test_count + 3);

    typename NumericType::cpptype val = 0;
    column->appendTypedValue(type.makeNullValue());
    for (int i = 0; i < test_count; ++i) {
      column->appendTypedValue(type.makeValue(&val));
      // One NULL in the middle.
      if (i == test_count / 2) {
        column->appendTypedValue(type.makeNullValue());
      }
    }
    column->appendTypedValue(type.makeNullValue());
    return column;
  }

  template <typename NumericType>
  void checkAggregationCountNumericValueAccessor(int test_count) {
    const NumericType &type = NumericType::Instance(true);
    initializeHandle(&type);
    CheckCountValue(
        0, *aggregation_handle_count_, *aggregation_handle_count_state_);

    std::unique_ptr<ColumnVectorsValueAccessor> accessor(
        new ColumnVectorsValueAccessor());
    accessor->addColumn(
        createColumnVectorNumeric<NumericType>(type, test_count));

    std::unique_ptr<AggregationState> va_state(
        aggregation_handle_count_->accumulateValueAccessor(
            {MultiSourceAttributeId(ValueAccessorSource::kBase, 0)},
            ValueAccessorMultiplexer(accessor.get())));

    // Test the state generated directly by accumulateValueAccessor(), and also
    // test after merging back.
    CheckCountValue(test_count, *aggregation_handle_count_, *va_state);

    aggregation_handle_count_->mergeStates(
        *va_state, aggregation_handle_count_state_.get());
    CheckCountValue(test_count,
                    *aggregation_handle_count_,
                    *aggregation_handle_count_state_);
  }

  template <typename StringType>
  void checkAggregationCountString(int test_count) {
    const StringType &type = StringType::Instance(10, true);
    initializeHandle(&type);
    CheckCountValue(
        0, *aggregation_handle_count_, *aggregation_handle_count_state_);

    std::string string_literal = "test_str";
    int count = 0;

    iterateHandle(aggregation_handle_count_state_.get(), type.makeNullValue());
    for (int i = 0; i < test_count; ++i) {
      iterateHandle(aggregation_handle_count_state_.get(),
                    type.makeValue(string_literal.c_str(), 10));
      ++count;
    }
    iterateHandle(aggregation_handle_count_state_.get(), type.makeNullValue());
    CheckCountValue(
        count, *aggregation_handle_count_, *aggregation_handle_count_state_);

    // Test mergeStates().
    std::unique_ptr<AggregationState> merge_state(
        aggregation_handle_count_->createInitialState());

    iterateHandle(merge_state.get(), type.makeNullValue());
    for (int i = 0; i < test_count; ++i) {
      iterateHandle(merge_state.get(),
                    type.makeValue(string_literal.c_str(), 10));
      ++count;
    }
    iterateHandle(merge_state.get(), type.makeNullValue());

    aggregation_handle_count_->mergeStates(
        *merge_state, aggregation_handle_count_state_.get());
    CheckCountValue(
        count, *aggregation_handle_count_, *aggregation_handle_count_state_);
  }

  template <typename ColumnVectorType>
  ColumnVector* createColumnVectorString(const Type &type, int test_count) {
    ColumnVectorType *column = new ColumnVectorType(type, test_count + 3);

    std::string string_literal = "test_str";
    column->appendTypedValue(type.makeNullValue());
    for (int i = 0; i < test_count; ++i) {
      column->appendTypedValue(type.makeValue(string_literal.c_str(), 10));
      // One NULL in the middle.
      if (i == test_count / 2) {
        column->appendTypedValue(type.makeNullValue());
      }
    }
    column->appendTypedValue(type.makeNullValue());

    return column;
  }

  template <typename StringType, typename ColumnVectorType>
  void checkAggregationCountStringValueAccessor(int test_count) {
    const StringType &type = StringType::Instance(10, true);
    initializeHandle(&type);
    CheckCountValue(
        0, *aggregation_handle_count_, *aggregation_handle_count_state_);

    std::unique_ptr<ColumnVectorsValueAccessor> accessor(
        new ColumnVectorsValueAccessor());
    accessor->addColumn(
        createColumnVectorString<ColumnVectorType>(type, test_count));

    std::unique_ptr<AggregationState> va_state(
        aggregation_handle_count_->accumulateValueAccessor(
            {MultiSourceAttributeId(ValueAccessorSource::kBase, 0)},
            ValueAccessorMultiplexer(accessor.get())));

    // Test the state generated directly by accumulateValueAccessor(), and also
    // test after merging back.
    CheckCountValue(test_count, *aggregation_handle_count_, *va_state);

    aggregation_handle_count_->mergeStates(
        *va_state, aggregation_handle_count_state_.get());
    CheckCountValue(test_count,
                    *aggregation_handle_count_,
                    *aggregation_handle_count_state_);
  }

  std::unique_ptr<AggregationHandle> aggregation_handle_count_;
  std::unique_ptr<AggregationState> aggregation_handle_count_state_;
  std::unique_ptr<StorageManager> storage_manager_;
};

typedef AggregationHandleCountTest AggregationHandleCountDeathTest;

TEST_F(AggregationHandleCountTest, CountStarTest) {
  checkAggregationCountNullary(0), checkAggregationCountNullary(10000);
}

TEST_F(AggregationHandleCountTest, CountStarAccumulateTest) {
  checkAggregationCountNullaryAccumulate(0),
      checkAggregationCountNullaryAccumulate(10000);
}

TEST_F(AggregationHandleCountTest, IntTypeTest) {
  checkAggregationCountNumeric<IntType>(0);
  checkAggregationCountNumeric<IntType>(10000);
}

TEST_F(AggregationHandleCountTest, LongTypeTest) {
  checkAggregationCountNumeric<LongType>(0);
  checkAggregationCountNumeric<LongType>(10000);
}

TEST_F(AggregationHandleCountTest, FloatTypeTest) {
  checkAggregationCountNumeric<FloatType>(0);
  checkAggregationCountNumeric<FloatType>(10000);
}

TEST_F(AggregationHandleCountTest, DoubleTypeTest) {
  checkAggregationCountNumeric<DoubleType>(0);
  checkAggregationCountNumeric<DoubleType>(10000);
}

TEST_F(AggregationHandleCountTest, CharTypeTest) {
  checkAggregationCountString<CharType>(0);
  checkAggregationCountString<CharType>(10000);
}

TEST_F(AggregationHandleCountTest, VarCharTypeTest) {
  checkAggregationCountString<VarCharType>(0);
  checkAggregationCountString<VarCharType>(10000);
}

TEST_F(AggregationHandleCountTest, IntTypeValueAccessorTest) {
  checkAggregationCountNumericValueAccessor<IntType>(0);
  checkAggregationCountNumericValueAccessor<IntType>(10000);
}

TEST_F(AggregationHandleCountTest, LongTypeValueAccessorTest) {
  checkAggregationCountNumericValueAccessor<LongType>(0);
  checkAggregationCountNumericValueAccessor<LongType>(10000);
}

TEST_F(AggregationHandleCountTest, FloatTypeValueAccessorTest) {
  checkAggregationCountNumericValueAccessor<FloatType>(0);
  checkAggregationCountNumericValueAccessor<FloatType>(10000);
}

TEST_F(AggregationHandleCountTest, DoubleTypeValueAccessorTest) {
  checkAggregationCountNumericValueAccessor<DoubleType>(0);
  checkAggregationCountNumericValueAccessor<DoubleType>(10000);
}

TEST_F(AggregationHandleCountTest, CharTypeValueAccessorTest) {
  checkAggregationCountStringValueAccessor<CharType, NativeColumnVector>(0);
  checkAggregationCountStringValueAccessor<CharType, NativeColumnVector>(10000);
}

TEST_F(AggregationHandleCountTest, VarCharTypeValueAccessorTest) {
  checkAggregationCountStringValueAccessor<VarCharType, IndirectColumnVector>(
      0);
  checkAggregationCountStringValueAccessor<VarCharType, IndirectColumnVector>(
      10000);
}

TEST_F(AggregationHandleCountTest, canApplyToTypeTest) {
  EXPECT_TRUE(ApplyToTypesTest(kInt));
  EXPECT_TRUE(ApplyToTypesTest(kLong));
  EXPECT_TRUE(ApplyToTypesTest(kFloat));
  EXPECT_TRUE(ApplyToTypesTest(kDouble));
  EXPECT_TRUE(ApplyToTypesTest(kChar));
  EXPECT_TRUE(ApplyToTypesTest(kVarChar));
}

TEST_F(AggregationHandleCountTest, ResultTypeForArgumentTypeTest) {
  EXPECT_TRUE(ResultTypeForArgumentTypeTest(kInt, kLong));
  EXPECT_TRUE(ResultTypeForArgumentTypeTest(kLong, kLong));
  EXPECT_TRUE(ResultTypeForArgumentTypeTest(kFloat, kLong));
  EXPECT_TRUE(ResultTypeForArgumentTypeTest(kDouble, kLong));
}

TEST_F(AggregationHandleCountTest, GroupByTableMergeTestCount) {
  const Type &long_non_null_type = LongType::Instance(false);
  initializeHandle(&long_non_null_type);
  storage_manager_.reset(new StorageManager("./test_count_data"));
  std::unique_ptr<AggregationStateHashTableBase> source_hash_table(
      AggregationStateHashTableFactory::CreateResizable(
          HashTableImplType::kSeparateChaining,
          std::vector<const Type *>(1, &long_non_null_type),
          10,
          {aggregation_handle_count_.get()},
          storage_manager_.get()));
  std::unique_ptr<AggregationStateHashTableBase> destination_hash_table(
      AggregationStateHashTableFactory::CreateResizable(
          HashTableImplType::kSeparateChaining,
          std::vector<const Type *>(1, &long_non_null_type),
          10,
          {aggregation_handle_count_.get()},
          storage_manager_.get()));

  PackedPayloadHashTable *destination_hash_table_derived =
      static_cast<PackedPayloadHashTable *>(destination_hash_table.get());

  PackedPayloadHashTable *source_hash_table_derived =
      static_cast<PackedPayloadHashTable *>(source_hash_table.get());

  // TODO(harshad) - Use TemplateUtil::CreateBoolInstantiatedInstance to
  // generate all the combinations of the bool template arguments and test them.
  AggregationHandleCount<true, false> *aggregation_handle_count_derived =
      static_cast<AggregationHandleCount<true, false> *>(
          aggregation_handle_count_.get());
  // We create three keys: first is present in both the hash tables, second key
  // is present only in the source hash table while the third key is present
  // the destination hash table only.
  std::vector<TypedValue> common_key;
  common_key.emplace_back(static_cast<std::int64_t>(0));
  std::vector<TypedValue> exclusive_source_key, exclusive_destination_key;
  exclusive_source_key.emplace_back(static_cast<std::int64_t>(1));
  exclusive_destination_key.emplace_back(static_cast<std::int64_t>(2));

  const std::int64_t common_key_source_count = 1;
  TypedValue common_key_source_count_val(common_key_source_count);

  const std::int64_t common_key_destination_count = 1;
  TypedValue common_key_destination_count_val(common_key_destination_count);

  const std::int64_t exclusive_key_source_count = 1;
  TypedValue exclusive_key_source_count_val(exclusive_key_source_count);

  const std::int64_t exclusive_key_destination_count = 1;
  TypedValue exclusive_key_destination_count_val(
      exclusive_key_destination_count);

  std::unique_ptr<AggregationStateCount> common_key_source_state(
      static_cast<AggregationStateCount *>(
          aggregation_handle_count_->createInitialState()));
  std::unique_ptr<AggregationStateCount> common_key_destination_state(
      static_cast<AggregationStateCount *>(
          aggregation_handle_count_->createInitialState()));
  std::unique_ptr<AggregationStateCount> exclusive_key_source_state(
      static_cast<AggregationStateCount *>(
          aggregation_handle_count_->createInitialState()));
  std::unique_ptr<AggregationStateCount> exclusive_key_destination_state(
      static_cast<AggregationStateCount *>(
          aggregation_handle_count_->createInitialState()));

  // Create count value states for keys.
  aggregation_handle_count_derived->iterateUnaryInl(
      common_key_source_state.get(), common_key_source_count_val);
  std::int64_t actual_val =
      aggregation_handle_count_->finalize(*common_key_source_state)
          .getLiteral<std::int64_t>();
  EXPECT_EQ(common_key_source_count_val.getLiteral<std::int64_t>(), actual_val);

  aggregation_handle_count_derived->iterateUnaryInl(
      common_key_destination_state.get(), common_key_destination_count_val);
  actual_val =
      aggregation_handle_count_->finalize(*common_key_destination_state)
          .getLiteral<std::int64_t>();
  EXPECT_EQ(common_key_destination_count_val.getLiteral<std::int64_t>(),
            actual_val);

  aggregation_handle_count_derived->iterateUnaryInl(
      exclusive_key_destination_state.get(),
      exclusive_key_destination_count_val);
  actual_val =
      aggregation_handle_count_->finalize(*exclusive_key_destination_state)
          .getLiteral<std::int64_t>();
  EXPECT_EQ(exclusive_key_destination_count_val.getLiteral<std::int64_t>(),
            actual_val);

  aggregation_handle_count_derived->iterateUnaryInl(
      exclusive_key_source_state.get(), exclusive_key_source_count_val);
  actual_val = aggregation_handle_count_->finalize(*exclusive_key_source_state)
                   .getLiteral<std::int64_t>();
  EXPECT_EQ(exclusive_key_source_count_val.getLiteral<std::int64_t>(),
            actual_val);

  // Add the key-state pairs to the hash tables.
  unsigned char buffer[100];
  buffer[0] = '\0';
  memcpy(buffer + 1,
         common_key_source_state.get()->getPayloadAddress(),
         aggregation_handle_count_.get()->getPayloadSize());
  source_hash_table_derived->upsertCompositeKey(common_key, buffer);

  memcpy(buffer + 1,
         common_key_destination_state.get()->getPayloadAddress(),
         aggregation_handle_count_.get()->getPayloadSize());
  destination_hash_table_derived->upsertCompositeKey(common_key, buffer);

  memcpy(buffer + 1,
         exclusive_key_source_state.get()->getPayloadAddress(),
         aggregation_handle_count_.get()->getPayloadSize());
  source_hash_table_derived->upsertCompositeKey(exclusive_source_key, buffer);

  memcpy(buffer + 1,
         exclusive_key_destination_state.get()->getPayloadAddress(),
         aggregation_handle_count_.get()->getPayloadSize());
  destination_hash_table_derived->upsertCompositeKey(exclusive_destination_key,
                                                     buffer);

  EXPECT_EQ(2u, destination_hash_table_derived->numEntries());
  EXPECT_EQ(2u, source_hash_table_derived->numEntries());

  HashTableMerger merger(destination_hash_table_derived);
  source_hash_table_derived->forEachCompositeKey(&merger);

  EXPECT_EQ(3u, destination_hash_table_derived->numEntries());

  CheckCountValue(
      common_key_destination_count_val.getLiteral<std::int64_t>() +
          common_key_source_count_val.getLiteral<std::int64_t>(),
      aggregation_handle_count_derived->finalizeHashTableEntry(
          destination_hash_table_derived->getSingleCompositeKey(common_key) +
          1));
  CheckCountValue(
      exclusive_key_destination_count_val.getLiteral<std::int64_t>(),
      aggregation_handle_count_derived->finalizeHashTableEntry(
          destination_hash_table_derived->getSingleCompositeKey(
              exclusive_destination_key) + 1));
  CheckCountValue(
      exclusive_key_source_count_val.getLiteral<std::int64_t>(),
      aggregation_handle_count_derived->finalizeHashTableEntry(
          source_hash_table_derived->getSingleCompositeKey(
              exclusive_source_key) + 1));
}

}  // namespace quickstep