//Copyright (c) 2018 Emil Dotchevski
//Copyright (c) 2018 Second Spectrum, Inc.

//Distributed under the Boost Software License, Version 1.0. (See accompanying
//file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)

#include <boost/leaf/expect.hpp>
#include <boost/leaf/exception.hpp>
#include <boost/leaf/preload.hpp>
#include "boost/core/lightweight_test.hpp"
#include <functional>

namespace leaf = boost::leaf;

struct my_error: std::exception { };

std::function<void()> thrower;

template <int A>
struct info
{
	int value;
};

void f1()
{
	thrower();
}

void f2()
{
	leaf::expect<info<1>> exp;
	try
	{
		f1();
		BOOST_TEST(false);
	}
	catch( std::exception const & ex )
	{
		leaf::get_error(ex).propagate( info<2>{2} );
		throw;
	}
}

void f3()
{
	leaf::expect<info<2>,info<3>> exp;
	auto propagate = leaf::defer( [ ] { return info<4>{4}; } );
	f2();
}

void f4()
{
	leaf::expect<info<1>,info<2>,info<3>,info<4>> exp;
	try
	{
		f3();
		BOOST_TEST(false);
	}
	catch( my_error const & e )
	{
		int c1=0, c2=0;
		handle_exception( exp, e,
			[&c1]( info<1>, info<2>, info<3>, info<4> )
			{
				++c1;
			},
			[&c2]( info<1> const & i1, info<2> const & i2, info<4> const & i4 )
			{
				BOOST_TEST(i1.value==1);
				BOOST_TEST(i2.value==2);
				BOOST_TEST(i4.value==4);
				++c2;
			}
		);
		BOOST_TEST(c1==0);
		BOOST_TEST(c2==1);
	}
	throw my_error();
}

void test( std::function<void()> const & f )
{
	thrower = f;
	leaf::expect<info<2>,info<3>,info<4>> exp;
	try
	{
		f4();
		BOOST_TEST(false);
	}
	catch( my_error const & e )
	{
		BOOST_TEST(!leaf::peek<info<2>>(exp,e));
		BOOST_TEST(!leaf::peek<info<3>>(exp,e));
		BOOST_TEST(!leaf::peek<info<4>>(exp,e));
		BOOST_TEST(leaf::leaf_detail::tl_slot_ptr<info<1>>()==0);
		BOOST_TEST(leaf::leaf_detail::tl_slot_ptr<info<2>>()!=0);
		BOOST_TEST(leaf::leaf_detail::tl_slot_ptr<info<3>>()!=0);
		BOOST_TEST(leaf::leaf_detail::tl_slot_ptr<info<4>>()!=0);
	}
}

int main()
{
	test( [ ]
	{
		throw leaf::exception( my_error(), info<1>{1} );
	} );

	test( [ ]
	{
		LEAF_THROW( my_error(), info<1>{1} );
	} );

	test( [ ]
	{
		auto propagate = leaf::defer( [ ] { return info<1>{1}; } );
		throw my_error();
	} );

	return boost::report_errors();
}