/*
 * © Copyright 2014 – Urheberrechtshinweis
 * Alle Rechte vorbehalten / All Rights Reserved
 *
 * Programmcode ist urheberrechtlich geschuetzt.
 * Das Urheberrecht liegt, soweit nicht ausdruecklich anders gekennzeichnet, bei Frank Ebner.
 * Keine Verwendung ohne explizite Genehmigung.
 * (vgl. § 106 ff UrhG / § 97 UrhG)
 */

#ifndef FLOORPLAN_3D_OUTLINE_H
#define FLOORPLAN_3D_OUTLINE_H

#include "Obstacle3.h"
#include "misc.h"
#include <unordered_map>
#include "../../geo/GPCPolygon2.h"

namespace Floorplan3D {

	class Outline {

	public:

		/** convert a floor (floor/ceiling) into triangles */
		std::vector<Obstacle3D> get(const Floorplan::Floor* f) {

			FloorPos fpos(f);

			std::vector<Obstacle3D> res;
			if (!f->enabled) {return res;}
			if (!f->outline.enabled) {return res;}

			// floor uses an outline based on "add" and "remove" areas
			// we need to create the apropriate triangles to model the polygon
			// including all holes (remove-areas)

			// process all "add" regions by type
			// [this allows for overlaps of the same type]
			std::unordered_map<std::string, GPCPolygon2> types;
			for (Floorplan::FloorOutlinePolygon* fop : f->outline) {
				if (fop->method == Floorplan::OutlineMethod::ADD) {
					if (fop->outdoor) {
						types["outdoor"].add(fop->poly);
					} else {
						types["indoor"].add(fop->poly);
					}
				}

			}

			// remove the "remove" regions from EVERY "add" region added within the previous step
			for (Floorplan::FloorOutlinePolygon* fop : f->outline) {
				if (fop->method == Floorplan::OutlineMethod::REMOVE) {
					for (auto& it : types) {
						it.second.remove(fop->poly);
					}
				}
				// allow for overlapping outdoor/indoor regions -> outdoor wins [remove outdoor part from indoor parts]
				if (fop->outdoor) {
					types["indoor"].remove(fop->poly);
				}
			}

			// create an obstacle for each type (indoor, outdoor)
			for (auto& it : types) {

				// TODO: variable type?
				Obstacle3D::Type type = (it.first == "indoor") ? (Obstacle3D::Type::GROUND_INDOOR) : (Obstacle3D::Type::GROUND_OUTDOOR);
				Obstacle3D obs(type, Floorplan::Material::CONCRETE);

				// convert them into polygons
				std::vector<std::vector<Point3>> polys = it.second.get(fpos.z1);

				// convert polygons (GL_TRIANGLE_STRIP) to triangles
				for (const std::vector<Point3>& pts : polys) {
					for (int i = 0; i < (int)pts.size() - 2; ++i) {

						// floor must be double-sided
						Triangle3 tria1 (pts[i+0], pts[i+1], pts[i+2]);
						Triangle3 tria2 (pts[i+2], pts[i+1], pts[i+0]);

						// ensure the triangle with the normal pointing downwards (towards bulding's cellar)
						// is below the triangle that points upwards (towards the sky)
						if (tria1.getNormal().z < 0) {std::swap(tria1, tria2);}

						// tria2 = ceiling of previous floor
						tria2 -= Point3(0,0,fpos.fh);

						// add both
						obs.triangles.push_back(tria1);
						obs.triangles.push_back(tria2);

					}
				}

				res.push_back(obs);

			}

			return res;

		}

	};

}

#endif // FLOORPLAN_3D_OUTLINE_H