#include <psemek/gfx/mesh.hpp>

#include <psemek/util/to_string.hpp>

namespace psemek::gfx
{

	mesh::mesh(mesh && other)
		: array_{std::move(other.array_)}
		, vertex_buffer_{std::move(other.vertex_buffer_)}
		, index_buffer_{std::move(other.index_buffer_)}
		, instance_buffer_{std::move(other.instance_buffer_)}
		, info_{other.info_}
	{
		other.info_ = mesh_info{};
	}

	mesh & mesh::operator = (mesh && other)
	{
		if (this == &other) return *this;

		array_ = std::move(other.array_);
		vertex_buffer_ = std::move(other.vertex_buffer_);
		index_buffer_ = std::move(other.index_buffer_);
		instance_buffer_ = std::move(other.instance_buffer_);
		info_ = other.info_;
		other.info_ = mesh_info{};

		return *this;
	}

	void mesh::draw() const
	{
		draw(0, is_indexed() ? index_count() : vertex_count(), instance_count());
	}

	void mesh::draw(std::size_t first, std::size_t count, std::size_t instance_count) const
	{
		if (is_indexed())
		{
			assert(first + count <= index_count());

			if (is_instanced())
			{
				assert(instance_count <= this->instance_count());

				if (count != 0 && instance_count != 0)
				{
					array_.bind();
					gl::DrawElementsInstanced(primitive_type(), count, index_type(), reinterpret_cast<char const *>(detail::index_size(index_type()) * first), instance_count);
				}
			}
			else
			{
				if (count != 0)
				{
					array_.bind();
					gl::DrawElements(primitive_type(), count, index_type(), reinterpret_cast<char const *>(detail::index_size(index_type()) * first));
				}
			}
		}
		else
		{
			assert(first + count <= vertex_count());

			if (is_instanced())
			{
				assert(instance_count <= this->instance_count());

				if (count != 0 && instance_count != 0)
				{
					array_.bind();
					gl::DrawArraysInstanced(primitive_type(), first, count, instance_count);
				}
			}
			else
			{
				if (count != 0)
				{
					array_.bind();
					gl::DrawArrays(primitive_type(), first, count);
				}
			}
		}
	}

}