#include <psemek/test/test.hpp>

#include <psemek/ui/impl/component_factory_base.hpp>
#include <psemek/ui/label.hpp>
#include <psemek/ui/rectangle.hpp>
#include <psemek/ui/button.hpp>
#include <psemek/ui/stack_layout.hpp>

#include <type_traits>

using namespace psemek;
using namespace psemek::ui;

namespace
{

	struct rectangle_impl
		: impl::component
	{
		void update(rectangle const &)
		{}
	};

	struct label_impl
		: impl::component
	{
		void update(label const &)
		{}
	};

	struct button_impl
		: impl::single_container
	{
		void update(button const &)
		{}
	};

	struct stack_layout_impl
		: impl::container
	{
		void update(stack_layout const &)
		{}
	};

	struct test_component_factory
		: impl::component_factory_base
	{
		int rectangle_count = 0;
		int label_count = 0;
		int button_count = 0;
		int stack_layout_count = 0;

		test_component_factory()
		{
			register_type<rectangle, rectangle_impl>([this]{ ++rectangle_count; return std::make_unique<rectangle_impl>(); });
			register_type<label, label_impl>([this]{ ++label_count; return std::make_unique<label_impl>(); });
			register_type<button, button_impl>([this]{ ++button_count; return std::make_unique<button_impl>(); });
			register_type<stack_layout, stack_layout_impl>([this]{ ++stack_layout_count; return std::make_unique<stack_layout_impl>(); });
		}
	};

	struct check_children_helper
	{
		impl::component & component;
		std::size_t i = 0;

		template <typename Type>
		void check()
		{
			if constexpr (std::is_same_v<Type, std::nullptr_t>)
			{
				expect_null(component.children()[i]);
			}
			else
			{
				expect_non_null(component.children()[i]);
				expect_dynamic_type(*component.children()[i], Type);
			}
			++i;
		}
	};

	template <typename ... Types>
	void check_children(impl::component & component)
	{
		expect_equal(component.children().size(), sizeof...(Types));

		check_children_helper helper{component};

		(void)helper;
		(helper.check<Types>(), ...);
	}

}

test_case(ui_impl_factory_element)
{
	test_component_factory factory;

	auto test_ui = label{};
	auto ui_root = factory.reconciliate(nullptr, test_ui);

	expect_non_null(ui_root);
	expect_dynamic_type(*ui_root, label_impl);

	expect_equal(factory.label_count, 1);
}

test_case(ui_impl_factory_single__container)
{
	test_component_factory factory;

	auto test_ui = button{
		.child = label{}
	};
	auto ui_root = factory.reconciliate(nullptr, test_ui);

	expect_non_null(ui_root);
	expect_dynamic_type(*ui_root, button_impl);
	check_children<label_impl>(*ui_root);

	expect_equal(factory.label_count, 1);
	expect_equal(factory.button_count, 1);
}

test_case(ui_impl_factory_single__container__null)
{
	test_component_factory factory;

	auto test_ui = button{};
	auto ui_root = factory.reconciliate(nullptr, test_ui);

	expect_non_null(ui_root);
	expect_dynamic_type(*ui_root, button_impl);
	check_children<std::nullptr_t>(*ui_root);

	expect_equal(factory.button_count, 1);
}

test_case(ui_impl_factory_container)
{
	test_component_factory factory;

	auto test_ui = stack_layout{{
		{label{}},
		{button{.child = label{}}},
		{label{}},
	}};
	auto ui_root = factory.reconciliate(nullptr, test_ui);

	expect_non_null(ui_root);
	expect_dynamic_type(*ui_root, stack_layout_impl);
	check_children<label_impl, button_impl, label_impl>(*ui_root);
	check_children<label_impl>(*ui_root->children()[1]);

	expect_equal(factory.label_count, 3);
	expect_equal(factory.button_count, 1);
	expect_equal(factory.stack_layout_count, 1);
}

test_case(ui_impl_factory_container__null)
{
	test_component_factory factory;

	auto test_ui = stack_layout{};
	auto ui_root = factory.reconciliate(nullptr, test_ui);

	expect_non_null(ui_root);
	expect_dynamic_type(*ui_root, stack_layout_impl);
	check_children<>(*ui_root);

	expect_equal(factory.stack_layout_count, 1);
}

test_case(ui_impl_factory_container__null__child)
{
	test_component_factory factory;

	auto test_ui = stack_layout{{
		{},
		{},
	}};
	auto ui_root = factory.reconciliate(nullptr, test_ui);

	expect_non_null(ui_root);
	expect_dynamic_type(*ui_root, stack_layout_impl);
	check_children<std::nullptr_t, std::nullptr_t>(*ui_root);

	expect_equal(factory.stack_layout_count, 1);
}

test_case(ui_impl_reconciliate_single__container)
{
	test_component_factory factory;

	auto child = react::source<std::any>(label{});

	expect_equal((*child).type(), typeid(label{}));

	auto test_ui = button{
		.child = child
	};

	expect_equal((*test_ui.child).type(), typeid(label{}));

	auto ui_root = factory.reconciliate(nullptr, test_ui);

	expect_non_null(ui_root);
	expect_dynamic_type(*ui_root, button_impl);
	check_children<label_impl>(*ui_root);

	expect_equal(factory.rectangle_count, 0);
	expect_equal(factory.label_count, 1);
	expect_equal(factory.button_count, 1);

	child.set(label{});

	check_children<label_impl>(*ui_root);

	expect_equal(factory.rectangle_count, 0);
	expect_equal(factory.label_count, 1);
	expect_equal(factory.button_count, 1);

	child.set(rectangle{});

	check_children<rectangle_impl>(*ui_root);

	expect_equal(factory.rectangle_count, 1);
	expect_equal(factory.label_count, 1);
	expect_equal(factory.button_count, 1);

	child.set(label{});

	check_children<label_impl>(*ui_root);

	expect_equal(factory.rectangle_count, 1);
	expect_equal(factory.label_count, 2);
	expect_equal(factory.button_count, 1);
}

test_case(ui_impl_reconciliate_container__no__keys)
{
	test_component_factory factory;

	react::source<std::vector<stack_layout::element>> children;

	auto test_ui = stack_layout{children};

	auto ui_root = factory.reconciliate(nullptr, test_ui);

	expect_equal(factory.stack_layout_count, 1);
	expect_equal(factory.label_count, 0);
	expect_equal(factory.button_count, 0);

	expect_non_null(ui_root);
	expect_dynamic_type(*ui_root, stack_layout_impl);
	check_children<>(*ui_root);

	children.set({{label{}}});

	check_children<label_impl>(*ui_root);

	expect_equal(factory.stack_layout_count, 1);
	expect_equal(factory.label_count, 1);
	expect_equal(factory.button_count, 0);

	children.set({{label{}}, {label{}}});

	check_children<label_impl, label_impl>(*ui_root);

	expect_equal(factory.stack_layout_count, 1);
	expect_equal(factory.label_count, 2);
	expect_equal(factory.button_count, 0);

	children.set({{label{}}, {label{}}, {label{}}});

	expect_equal(factory.stack_layout_count, 1);
	expect_equal(factory.label_count, 3);
	expect_equal(factory.button_count, 0);

	children.set({{label{}}, {button{}}, {label{}}});

	expect_equal(factory.stack_layout_count, 1);
	expect_equal(factory.label_count, 3);
	expect_equal(factory.button_count, 1);

	children.set({{button{}}, {button{}}, {label{}}});

	expect_equal(factory.stack_layout_count, 1);
	expect_equal(factory.label_count, 3);
	expect_equal(factory.button_count, 2);

	children.set({{button{}}, {button{}}});

	expect_equal(factory.stack_layout_count, 1);
	expect_equal(factory.label_count, 3);
	expect_equal(factory.button_count, 2);

	children.set({{button{}}});

	expect_equal(factory.stack_layout_count, 1);
	expect_equal(factory.label_count, 3);
	expect_equal(factory.button_count, 2);

	children.set({});

	expect_equal(factory.stack_layout_count, 1);
	expect_equal(factory.label_count, 3);
	expect_equal(factory.button_count, 2);
}

test_case(ui_impl_reconciliate_container__keys)
{
	test_component_factory factory;

	react::source<std::vector<stack_layout::element>> children;

	auto test_ui = stack_layout{children};

	auto ui_root = factory.reconciliate(nullptr, test_ui);

	expect_equal(factory.stack_layout_count, 1);
	expect_equal(factory.label_count, 0);

	expect_non_null(ui_root);
	expect_dynamic_type(*ui_root, stack_layout_impl);
	check_children<>(*ui_root);

	children.set({{label{}, "Label 0"}});

	check_children<label_impl>(*ui_root);

	auto label0 = ui_root->children()[0].get();

	expect_equal(factory.stack_layout_count, 1);
	expect_equal(factory.label_count, 1);

	children.set({{label{}, "Label 0"}, {label{}, "Label 1"}});

	check_children<label_impl, label_impl>(*ui_root);
	expect_equal(ui_root->children()[0].get(), label0);
	auto label1 = ui_root->children()[1].get();

	expect_equal(factory.stack_layout_count, 1);
	expect_equal(factory.label_count, 2);

	children.set({{label{}, "Label 1"}, {label{}, "Label 0"}});

	check_children<label_impl, label_impl>(*ui_root);
	expect_equal(ui_root->children()[0].get(), label1);
	expect_equal(ui_root->children()[1].get(), label0);

	expect_equal(factory.stack_layout_count, 1);
	expect_equal(factory.label_count, 2);

	children.set({{label{}, "Label 0"}, {label{}, "Label 2"}});

	check_children<label_impl, label_impl>(*ui_root);
	expect_equal(ui_root->children()[0].get(), label0);

	expect_equal(factory.stack_layout_count, 1);
	expect_equal(factory.label_count, 3);
}