/*
 * Copyright 2018, Oath Inc. Licensed under the terms of the
 * Apache License 2.0. See LICENSE file at the project root for terms.
 */

#include <cppunit/TestFixture.h>
#include <cppunit/extensions/HelperMacros.h>

#include "cpc_union.hpp"

namespace datasketches {

static const double RELATIVE_ERROR_FOR_LG_K_11 = 0.02;

class cpc_union_test: public CppUnit::TestFixture {

  CPPUNIT_TEST_SUITE(cpc_union_test);
  CPPUNIT_TEST(lg_k_limits);
  CPPUNIT_TEST(empty);
  CPPUNIT_TEST(copy);
  CPPUNIT_TEST(custom_seed);
  CPPUNIT_TEST_SUITE_END();

  void lg_k_limits() {
    cpc_union u1(CPC_MIN_LG_K); // this should work
    cpc_union u2(CPC_MAX_LG_K); // this should work
    CPPUNIT_ASSERT_THROW(cpc_union u3(CPC_MIN_LG_K - 1), std::invalid_argument);
    CPPUNIT_ASSERT_THROW(cpc_union u4(CPC_MAX_LG_K + 1), std::invalid_argument);
  }

  void empty() {
    cpc_union u(11);
    auto sketch_ptr(u.get_result());
    CPPUNIT_ASSERT(sketch_ptr->is_empty());
    CPPUNIT_ASSERT_EQUAL(0.0, sketch_ptr->get_estimate());
  }

  void copy() {
    cpc_sketch s(11);
    s.update(1);
    cpc_union u1(11);
    u1.update(s);

    cpc_union u2 = u1; // copy constructor
    auto sp1(u2.get_result());
    CPPUNIT_ASSERT(!sp1->is_empty());
    CPPUNIT_ASSERT_DOUBLES_EQUAL(1, sp1->get_estimate(), RELATIVE_ERROR_FOR_LG_K_11);
    s.update(2);
    u2.update(s);
    u1 = u2; // operator=
    auto sp2(u1.get_result());
    CPPUNIT_ASSERT(!sp2->is_empty());
    CPPUNIT_ASSERT_DOUBLES_EQUAL(2, sp2->get_estimate(), RELATIVE_ERROR_FOR_LG_K_11);
  }

  void custom_seed() {
    cpc_sketch s(11, 123);

    s.update(1);
    s.update(2);
    s.update(3);

    cpc_union u1(11, 123);
    u1.update(s);
    auto sp(u1.get_result());
    CPPUNIT_ASSERT(!sp->is_empty());
    CPPUNIT_ASSERT_DOUBLES_EQUAL(3, sp->get_estimate(), RELATIVE_ERROR_FOR_LG_K_11);

    // incompatible seed
    cpc_union u2(11, 234);
    CPPUNIT_ASSERT_THROW(u2.update(s), std::invalid_argument);
  }

};

CPPUNIT_TEST_SUITE_REGISTRATION(cpc_union_test);

} /* namespace datasketches */