// GNU Lesser General Public License v3.0
// Copyright (c) 2023 Bart Beumer <bart@4beumer.nl>
//
// This program is free software; you can redistribute it and/or modify it
// under the terms of the GNU Lesser General Public License v3.0 as published by
// the Free Software Foundation.
//
#include "bmrshared/invoke.hpp"
#include "MockDataSource.hpp"
#include <gmock/gmock.h>
#include <gtest/gtest.h>
#include <type_traits>

using ::testing::An;
using ::testing::ElementsAre;
using ::testing::Return;
using ::testing::SetArgReferee;
using ::testing::TypedEq;

using bmrshared::flexible_value;
using bmrshared::MockDataSource;

namespace
{
// Compile-time test of some helper templates.

static_assert(std::is_same<typename bmrshared::detail::tuple_keepelemsfront<std::tuple<int, char>, 0>::tuple,
                           std::tuple<>>::value);
static_assert(std::is_same<typename bmrshared::detail::tuple_keepelemsfront<std::tuple<int, char>, 1>::tuple,
                           std::tuple<int>>::value);
static_assert(std::is_same<typename bmrshared::detail::tuple_keepelemsfront<std::tuple<int, char>, 2>::tuple,
                           std::tuple<int, char>>::value);

static_assert(std::is_same<typename bmrshared::detail::tuple_rmelemsback<std::tuple<int, char>, 0>::tuple,
                           std::tuple<int, char>>::value);
static_assert(std::is_same<typename bmrshared::detail::tuple_rmelemsback<std::tuple<int, char>, 1>::tuple,
                           std::tuple<int>>::value);
static_assert(
    std::is_same<typename bmrshared::detail::tuple_rmelemsback<std::tuple<int, char>, 2>::tuple, std::tuple<>>::value);


class TestAddition
{
  public:
    uint64_t AddNumbers(uint64_t left, uint64_t right) { return left + (right * 2); }
    uint64_t AddNumbersConst(uint64_t left, uint64_t right) const { return left + (right * 2); }
};
} // namespace


TEST(InvokeTest, Ok_Callable)
{
    auto fn = [](int64_t a, int64_t b)
    {
        return (a + (b * 2));
    };
    std::array<std::string, 2> names = {"a", "b"};

    MockDataSource mockSrc;
    EXPECT_CALL(mockSrc, GetKeys()).WillRepeatedly(Return(std::vector<std::string>{"a", "b"}));
    EXPECT_CALL(mockSrc, Get("a", An<int64_t&>())).WillRepeatedly(SetArgReferee<1>(42));
    EXPECT_CALL(mockSrc, Get("b", An<int64_t&>())).WillRepeatedly(SetArgReferee<1>(21));

    flexible_value returnValue = bmrshared::invoke(fn, names, mockSrc);
    EXPECT_EQ(returnValue.as<int64_t>(), 84);
}

TEST(InvokeTest, Ok_Callable_LastArg)
{
    auto fn = [](int64_t a, int64_t b, int64_t lastArg)
    {
        return ((lastArg * 4) + a + (b * 2));
    };
    std::array<std::string, 2> names = {"a", "b"};

    MockDataSource mockSrc;
    EXPECT_CALL(mockSrc, GetKeys()).WillRepeatedly(Return(std::vector<std::string>{"a", "b"}));
    EXPECT_CALL(mockSrc, Get("a", An<int64_t&>())).WillRepeatedly(SetArgReferee<1>(42));
    EXPECT_CALL(mockSrc, Get("b", An<int64_t&>())).WillRepeatedly(SetArgReferee<1>(21));

    flexible_value returnValue = bmrshared::invoke(fn, names, mockSrc, 1000);
    EXPECT_EQ(returnValue.as<int64_t>(), 4084);
}

TEST(InvokeTest, Ok_Ptr_Member)
{
    std::array<std::string, 2> names = {"left", "right"};

    MockDataSource mockSrc;
    EXPECT_CALL(mockSrc, GetKeys()).WillRepeatedly(Return(std::vector<std::string>{"left", "right"}));
    EXPECT_CALL(mockSrc, Get("left", An<uint64_t&>())).WillRepeatedly(SetArgReferee<1>(100));
    EXPECT_CALL(mockSrc, Get("right", An<uint64_t&>())).WillRepeatedly(SetArgReferee<1>(20));

    TestAddition functor;
    flexible_value returnValue = bmrshared::invoke(functor, &TestAddition::AddNumbers, names, mockSrc);
    EXPECT_EQ(returnValue.as<uint64_t>(), 140);
}

TEST(InvokeTest, Ok_Ptr_Const_Member_Const)
{
    std::array<std::string, 2> names = {"left", "right"};

    MockDataSource mockSrc;
    EXPECT_CALL(mockSrc, GetKeys()).WillRepeatedly(Return(std::vector<std::string>{"left", "right"}));
    EXPECT_CALL(mockSrc, Get("left", An<uint64_t&>())).WillRepeatedly(SetArgReferee<1>(100));
    EXPECT_CALL(mockSrc, Get("right", An<uint64_t&>())).WillRepeatedly(SetArgReferee<1>(20));

    const TestAddition functor;
    flexible_value returnValue = bmrshared::invoke(functor, &TestAddition::AddNumbersConst, names, mockSrc);
    EXPECT_EQ(returnValue.as<uint64_t>(), 140);
}

TEST(InvokeTest, Ok_Ptr_Member_Const)
{
    std::array<std::string, 2> names = {"left", "right"};

    MockDataSource mockSrc;
    EXPECT_CALL(mockSrc, GetKeys()).WillRepeatedly(Return(std::vector<std::string>{"left", "right"}));
    EXPECT_CALL(mockSrc, Get("left", An<uint64_t&>())).WillRepeatedly(SetArgReferee<1>(100));
    EXPECT_CALL(mockSrc, Get("right", An<uint64_t&>())).WillRepeatedly(SetArgReferee<1>(20));

    TestAddition functor;
    flexible_value returnValue = bmrshared::invoke(functor, &TestAddition::AddNumbersConst, names, mockSrc);
    EXPECT_EQ(returnValue.as<uint64_t>(), 140);
}

TEST(InvokeTest, Ok_ExtraArgumentByRefChanged)
{
    auto fn = [](int64_t a, int64_t& lastArg)
    {
        lastArg = a;
        return true;
    };
    std::array<std::string, 1> names = {"a"};

    MockDataSource mockSrc;
    EXPECT_CALL(mockSrc, GetKeys()).WillRepeatedly(Return(std::vector<std::string>{"a"}));
    EXPECT_CALL(mockSrc, Get("a", An<int64_t&>())).WillRepeatedly(SetArgReferee<1>(42));

    int64_t lastArg = 0;
    flexible_value returnValue = bmrshared::invoke(fn, names, mockSrc, lastArg);
    EXPECT_EQ(returnValue.as<bool>(), true);
    EXPECT_EQ(lastArg, 42);
}