#include "optional.h"
#include "catch.hpp"

TEST_CASE("Empty")
{
    Optional_Integer o;
    REQUIRE_FALSE(o.has_value());
    REQUIRE_THROWS_AS(o.value(), invalid_optional_access);
}

TEST_CASE("initial and get value")
{
    Optional_Integer o{5};
    CHECK(o.has_value());
    CHECK(o.value() == 5);
}

TEST_CASE("reset and swap")
{
    Optional_Integer o{5};
    SECTION("reset")
    {
        o.reset();
        CHECK_FALSE(o.has_value());
    }
    SECTION("swap with empty")
    {
        Optional_Integer e;
        o.swap(e);
        CHECK_FALSE(o.has_value());
        CHECK(e.has_value());
        CHECK(e.value() == 5);
    }
    SECTION("swap with set")
    {
        Optional_Integer r {3};
        r.swap(o);
        CHECK(o.value() == 3);
        CHECK(r.value() == 5);
    }
}

TEST_CASE("assignment")
{
    SECTION("empty")
    {
        Optional_Integer o;
        o = 5;
        CHECK(o.value() == 5);
    }
    SECTION("had value")
    {
        Optional_Integer o{5};
        o = 6;
        CHECK(o.value() == 6);
    }
    SECTION("copy existing")
    {
        Optional_Integer o1 {2};
        Optional_Integer o2;
        o2 = o1;
        CHECK(o2.value() == 2);
        CHECK(o1.value() == 2);
        o1 = 4;
        CHECK(o2.value() == 2);
        CHECK(o1.value() == 4);
    }
}

Optional_Integer fun(bool returns)
{
    if ( returns )
        return Optional_Integer{5};
    return {};
}

TEST_CASE("call fun")
{
    Optional_Integer o;
    SECTION("set")
    {
        o = fun(true);
        CHECK(o.value() == 5);
    }
    SECTION("not set")
    {
        o = fun(false);
        CHECK_FALSE(o.has_value());
    }
}