/*
 * 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 <catch2/catch.hpp>
#include <sstream>
#include <stdexcept>

#include "frequent_items_sketch.hpp"
#include "test_type.hpp"
#include "test_allocator.hpp"

namespace datasketches {

using frequent_test_type_sketch = frequent_items_sketch<test_type, float, test_type_hash, test_type_equal, test_allocator<test_type>>;
using alloc = test_allocator<test_type>;

TEST_CASE("frequent items: custom type", "[frequent_items_sketch]") {
  test_allocator_total_bytes = 0;
  {
    frequent_test_type_sketch sketch(3, frequent_test_type_sketch::LG_MIN_MAP_SIZE, test_type_equal(), 0);
    sketch.update(1, 10); // should survive the purge
    sketch.update(2);
    sketch.update(3);
    sketch.update(4);
    sketch.update(5);
    sketch.update(6);
    sketch.update(7);
    test_type a8(8);
    sketch.update(a8);
    REQUIRE_FALSE(sketch.is_empty());
    REQUIRE(sketch.get_total_weight() == 17);
    REQUIRE(sketch.get_estimate(1) == 10);

    auto items = sketch.get_frequent_items(frequent_items_error_type::NO_FALSE_POSITIVES);
    REQUIRE(items.size() == 1); // only 1 item should be above threshold
    REQUIRE(items[0].get_item().get_value() == 1);
    REQUIRE(items[0].get_estimate() == 10);

    std::stringstream s(std::ios::in | std::ios::out | std::ios::binary);
    sketch.serialize(s, test_type_serde());
    auto sketch2 = frequent_test_type_sketch::deserialize(s, test_type_serde(), test_type_equal(), 0);
    REQUIRE_FALSE(sketch2.is_empty());
    REQUIRE(sketch2.get_total_weight() == 17);
    REQUIRE(sketch2.get_estimate(1) == 10);
    REQUIRE(sketch.get_num_active_items() == sketch2.get_num_active_items());
    REQUIRE(sketch.get_maximum_error() == sketch2.get_maximum_error());

    auto bytes = sketch.serialize(0, test_type_serde());
    auto sketch3 = frequent_test_type_sketch::deserialize(bytes.data(), bytes.size(), test_type_serde(),
        test_type_equal(), 0);
    REQUIRE_FALSE(sketch3.is_empty());
    REQUIRE(sketch3.get_total_weight() == 17);
    REQUIRE(sketch3.get_estimate(1) == 10);
    REQUIRE(sketch.get_num_active_items() == sketch3.get_num_active_items());
    REQUIRE(sketch.get_maximum_error() == sketch3.get_maximum_error());
  }
  REQUIRE(test_allocator_total_bytes == 0);
}

// this is to see the debug print from test_type if enabled there to make sure items are moved
TEST_CASE("frequent items: moving merge", "[frequent_items_sketch]") {
  test_allocator_total_bytes = 0;
  {
    frequent_test_type_sketch sketch1(3, frequent_test_type_sketch::LG_MIN_MAP_SIZE, test_type_equal(), 0);
    sketch1.update(1);

    frequent_test_type_sketch sketch2(3, frequent_test_type_sketch::LG_MIN_MAP_SIZE, test_type_equal(), 0);
    sketch2.update(2);

    sketch2.merge(std::move(sketch1));
    REQUIRE(sketch2.get_total_weight() == 2);
  }
  REQUIRE(test_allocator_total_bytes == 0);
}

TEST_CASE("frequent items: negative weight", "[frequent_items_sketch]") {
  test_allocator_total_bytes = 0;
  {
    frequent_test_type_sketch sketch(3, frequent_test_type_sketch::LG_MIN_MAP_SIZE, test_type_equal(), 0);
    REQUIRE_THROWS_AS(sketch.update(1, -1), std::invalid_argument);
  }
  REQUIRE(test_allocator_total_bytes == 0);
}

} /* namespace datasketches */