/**
	This file is a part of our_dick
	Copyright (C) 2020 rexy712

	This program is free software: you can redistribute it and/or modify
	it under the terms of the GNU Affero General Public License as published by
	the Free Software Foundation, either version 3 of the License, or
	(at your option) any later version.

	This program is distributed in the hope that it will be useful,
	but WITHOUT ANY WARRANTY; without even the implied warranty of
	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
	GNU Affero General Public License for more details.

	You should have received a copy of the GNU Affero General Public License
	along with this program.  If not, see <http://www.gnu.org/licenses/>.
*/

#ifndef OUR_DICK_ENGINE_CAMERA_HPP
#define OUR_DICK_ENGINE_CAMERA_HPP

#include "graphics/gl_include.hpp" //GLfloat
#include "math/math.hpp"
#include "object.hpp"

namespace egn{

	class camera_iface : public object
	{
	protected:
		enum update{
			VIEW_UPDATE = 8,
			PROJ_UPDATE = 16,
		};
	protected:
		//mutable because they're only really a cached value representation of the data
		//in position, orientation, near, far, etc
		mutable math::mat4<GLfloat> m_projection_matrix; //camera-to-sceen matrix
		mutable math::mat4<GLfloat> m_view_matrix;       //world-to-camera matrix
		GLfloat m_near = 1;                      //near clipping plane in camera space
		GLfloat m_far = 100;                     //far clipping plane in camera space

	public:
		camera_iface() = default;
		camera_iface(const math::mat4<GLfloat>& proj, GLfloat n, GLfloat f);
		camera_iface(const camera_iface&) = default;
		camera_iface(camera_iface&&) = default;
		virtual ~camera_iface() = default;

		camera_iface& operator=(const camera_iface&) = default;
		camera_iface& operator=(camera_iface&&) = default;

		void set_position(const math::vec3<GLfloat>& pos)override;
		void set_orientation(const math::quaternion<GLfloat>& distance)override;

		//getters
		const math::mat4<GLfloat>& get_projection_matrix()const;
		const math::mat4<GLfloat>& get_view_matrix()const;
		GLfloat get_near_plane()const;
		GLfloat get_far_plane()const;

		//setters
		void set_near_plane(GLfloat n);
		void set_far_plane(GLfloat f);

	protected:
		void recalc_view_matrix()const;
		virtual void recalc_projection_matrix()const = 0;
	};

	class ortho_camera : public camera_iface
	{
	protected:
		GLfloat m_width, m_height; //width and height of the camera space box

	public:
		ortho_camera(GLfloat w, GLfloat h, GLfloat n, GLfloat f);
		ortho_camera(const ortho_camera&) = default;
		ortho_camera(ortho_camera&&) = default;
		~ortho_camera() = default;

		ortho_camera& operator=(const ortho_camera&) = default;
		ortho_camera& operator=(ortho_camera&&) = default;

		GLfloat get_projection_width()const;
		GLfloat get_projection_height()const;

		void set_projection_width(GLfloat w);
		void set_projection_height(GLfloat h);
		void set_projection_box(GLfloat w, GLfloat h);
	protected:
		void recalc_projection_matrix()const override;
	};

}

#endif