#include <psemek/ui/default_element_factory.hpp>

#include <psemek/ui/box_shape.hpp>

namespace psemek::ui
{

	namespace
	{

		struct button_impl
			: button
		{
			button_impl(std::string text)
			{
				set_label(std::make_shared<struct label>());
				label()->set_text(std::move(text));
				label()->set_valign(label::valignment::center);
				label()->set_halign(label::halignment::center);
				label()->set_overflow(label::overflow_mode::drop);
				label()->set_multiline(label::multiline_mode::none);
			}

			button_impl(std::shared_ptr<gfx::texture_2d> tex)
			{
				set_icon(std::make_shared<image_view>());
				icon()->set_image(std::move(tex));
				icon()->set_downscale(false);
				icon()->set_upscale(false);
			}

			struct shape const & shape() const override
			{
				return shape_;
			}

			void reshape(geom::box<float, 2> const & bbox) override
			{
				shape_.box = bbox;
				auto st = merged_style();
				element * c = label() ? (element *)label() : icon();
				if (st && c) c->reshape(geom::shrink(bbox, 1.f * (*st->border_width + *st->inner_margin)));
			}

			void on_state_changed() override
			{
				gfx::color_rgba color{0, 0, 0, 0};

				switch (state()) {
				case state_t::mouseover:
					color = {255, 255, 255, 63};
					break;
				case state_t::mousedown:
					color = {0, 0, 0, 63};
					break;
				default:
					break;
				}

				if (icon())
					icon()->set_color(color);
			}

			void draw(painter & p) const override
			{
				auto st = merged_style();
				if (!st) return;

				if (st->shadow_offset != geom::vector{0, 0})
					p.draw_rect(shape_.box + geom::cast<float>(*st->shadow_offset), *st->shadow_color);

				if (st->border_width > 0)
					p.draw_rect(shape_.box, *st->border_color);

				gfx::color_rgba color = *st->fg_color;
				if (state() == state_t::mouseover)
					color = *st->highlight_color;
				else if (state() == state_t::mousedown)
					color = *st->action_color;
				p.draw_rect(geom::shrink(shape_.box, 1.f * (*st->border_width)), color);
			}

			geom::box<float, 2> size_constraints() const override
			{
				auto sc = element::size_constraints();

				element const * c = label() ? (element const *)label() : icon();

				if (c)
				{
					sc = c->size_constraints();

					if (auto st = merged_style())
					{
						float extra = 2.f * (*st->border_width + *st->inner_margin);
						sc[0] += extra;
						sc[1] += extra;
					}
				}

				return sc;
			}

		private:
			box_shape shape_;
		};

		struct frame_impl
			: frame
		{
			struct shape const & shape() const override { return shape_; }

			void reshape(geom::box<float, 2> const & bbox) override
			{
				shape_.box = bbox;
				auto st = merged_style();
				if (!st) return;
				for (auto c : children())
					if (c) c->reshape(geom::shrink(bbox, 1.f * (*st->border_width + *st->outer_margin)));
			}

			geom::box<float, 2> size_constraints() const override
			{
				geom::box<float, 2> r = element::size_constraints();

				for (auto c : children())
					if (c)
						r = c->size_constraints();

				auto st = merged_style();
				if (st)
				{
					float extra = 2.f * (*st->border_width + *st->outer_margin);
					r[0] += extra;
					r[1] += extra;
				}

				if (min_size())
				{
					auto s = *min_size();
					r[0].min = s[0];
					r[1].min = s[1];
				}

				if (max_size())
				{
					auto s = *max_size();
					r[0].max = s[0];
					r[1].max = s[1];
				}

				return r;
			}

			void draw(painter & p) const override
			{
				auto st = merged_style();
				if (!st) return;

				if (st->shadow_offset != geom::vector{0, 0})
					p.draw_rect(shape_.box + geom::cast<float>(*st->shadow_offset), *st->shadow_color);

				if (st->border_width > 0)
					p.draw_rect(shape_.box, *st->border_color);
				p.draw_rect(geom::shrink(shape_.box, 1.f * (*st->border_width)), *st->bg_color);
			}

		private:
			box_shape shape_;
		};

	}

	struct default_element_factory::impl
	{};

	default_element_factory::default_element_factory()
		: pimpl_{make_impl()}
	{}

	default_element_factory::~default_element_factory() = default;

	std::shared_ptr<button> default_element_factory::make_button(std::string text)
	{
		return std::make_shared<button_impl>(std::move(text));
	}

	std::shared_ptr<button> default_element_factory::make_button(std::shared_ptr<gfx::texture_2d> icon)
	{
		return std::make_shared<button_impl>(std::move(icon));
	}

	std::shared_ptr<label> default_element_factory::make_label(std::string text)
	{
		auto r = std::make_shared<label>();
		r->set_text(text);
		return r;
	}

	std::shared_ptr<frame> default_element_factory::make_frame()
	{
		return std::make_shared<frame_impl>();
	}

	std::shared_ptr<screen> default_element_factory::make_screen()
	{
		return std::make_shared<screen>();
	}

	std::shared_ptr<grid_layout> default_element_factory::make_grid_layout()
	{
		return std::make_shared<grid_layout>();
	}

}