#pragma once

#include <charcoal/Batch.h>
#include <charcoal/Renderable.h>
#include <charcoal/Poseable.h>
#include "BuiltinBatch.h"

namespace charcoal
{
	namespace builtin
	{
		// Note: If anything is changed in this file, it must also be changed in Poseable2DBatch
		template <typename VertexType, typename IndexType, int orientation_attrib_offset, typename RenderableType = RenderableT<VertexType, IndexType> >
		class PoseableBatch : public builtin::Batch<VertexType, IndexType, 1, RenderableType>
		{
		public:
			PoseableBatch(RenderableType* renderable)
				: builtin::Batch<VertexType, IndexType, 1, RenderableType>(renderable, 0)
			{}

			virtual ~PoseableBatch() {}

			void reset_rendered()
			{
				m_orientation_elements.clear();
				charcoal::InstancedBatch<VertexType, IndexType, RenderableType>::set_render_count(0);
				// Just thinking, maybe want to not make want set_render_count to be public... The end-developer
				// could screw up things by using that function. Then again, it could allow for preventing of
				// needing to resize the element buffers once that optimization is made.
			}

			void add_rendered(const Poseable& poseable)
			{
				m_orientation_elements.emplace_back(poseable.get_orientation_matrix());
				charcoal::InstancedBatch<VertexType, IndexType, RenderableType>::m_render_count++;
			}

		protected:
			void setup_element_buffers() override
			{
				// This is (was) worthless because it is also done in update_element_buffers.
				//glBindBuffer(GL_ARRAY_BUFFER, charcoal::ElementBatch<1>::m_element_buffers[0]);
				//glBufferData(GL_ARRAY_BUFFER, m_orientation_elements.size() * sizeof(mat4), NULL, GL_STREAM_DRAW);
				// TODO: Find a way to not have to do a re-allocation every frame.
				// While we're like this, I guess the adding and resetting of rendered can be changed though!
			}

			void resize_element_buffers() override
			{
				// Do nothing. This is done in update_element_buffers for some reason... Maybe this should be changed...
			}

			void update_element_buffers() override
			{
				// TODO: There are probably better ways to do this. Should check with the old engine to see what I did there.
				glBindBuffer(GL_ARRAY_BUFFER, charcoal::ElementBatch<1>::m_element_buffers[0]);
				glBufferData(GL_ARRAY_BUFFER, m_orientation_elements.size() * sizeof(mat4), NULL, GL_STREAM_DRAW);
				glBufferSubData(GL_ARRAY_BUFFER, 0, m_orientation_elements.size() * sizeof(mat4), m_orientation_elements.data());
			}

			virtual void setup_vao_vertex() = 0;

			void setup_vao() override
			{
				setup_vao_vertex();

				glBindBuffer(GL_ARRAY_BUFFER, charcoal::ElementBatch<1>::m_element_buffers[0]);

				glEnableVertexAttribArray(orientation_attrib_offset + 0);
				glEnableVertexAttribArray(orientation_attrib_offset + 1);
				glEnableVertexAttribArray(orientation_attrib_offset + 2);
				glEnableVertexAttribArray(orientation_attrib_offset + 3);

				glVertexAttribPointer(orientation_attrib_offset + 0, 4, GL_FLOAT, GL_FALSE, sizeof(mat4), (void*)(0 * sizeof(mat4::col_type)));
				glVertexAttribPointer(orientation_attrib_offset + 1, 4, GL_FLOAT, GL_FALSE, sizeof(mat4), (void*)(1 * sizeof(mat4::col_type)));
				glVertexAttribPointer(orientation_attrib_offset + 2, 4, GL_FLOAT, GL_FALSE, sizeof(mat4), (void*)(2 * sizeof(mat4::col_type)));
				glVertexAttribPointer(orientation_attrib_offset + 3, 4, GL_FLOAT, GL_FALSE, sizeof(mat4), (void*)(3 * sizeof(mat4::col_type)));

				glVertexAttribDivisor(orientation_attrib_offset + 0, 1); // Send the orientation data for each instance drawn
				glVertexAttribDivisor(orientation_attrib_offset + 1, 1); // Send the orientation data for each instance drawn
				glVertexAttribDivisor(orientation_attrib_offset + 2, 1); // Send the orientation data for each instance drawn
				glVertexAttribDivisor(orientation_attrib_offset + 3, 1); // Send the orientation data for each instance drawn
			}

			std::vector<mat4> m_orientation_elements;
		};
	}
}