#ifndef MODELFACTORY_H
#define MODELFACTORY_H

#include "../../../floorplan/v2/Floorplan.h"
#include "../../../geo/Triangle3.h"
#include "ModelFactoryHelper.h"
#include "Obstacle3.h"
#include "Cube.h"

/**
 * convert an indoor map into a 3D model based on triangles
 */
class ModelFactory {

private:

	bool exportCeilings = true;
	bool exportObstacles = true;
	bool exportWallTops = false;

	const Floorplan::IndoorMap* map;

public:


	/** ctor */
	ModelFactory(const Floorplan::IndoorMap* map) : map(map) {

	}


	/** get all triangles grouped by obstacle */
	std::vector<Obstacle3D> triangulize() {

		std::vector<Obstacle3D> res;

		// process each floor
		for (const Floorplan::Floor* f : map->floors) {

			// triangulize the floor itself (floor/ceiling)
			if (exportCeilings) {res.push_back(getTriangles(f));}

			// process each obstacle within the floor
			for (const Floorplan::FloorObstacle* fo : f->obstacles) {

				// handle line obstacles
				const Floorplan::FloorObstacleLine* fol = dynamic_cast<const Floorplan::FloorObstacleLine*>(fo);
				if (fol) {
					if (fol->type == Floorplan::ObstacleType::HANDRAIL) {continue;}
					if (exportObstacles) {res.push_back(getTriangles(f, fol));}
				}

			}

			// TODO: remove
			//break;

		}

		return res;

	}


	/** DEBUG: convert to .obj file code for exporting */
	std::string toOBJ() {

		const std::vector<Obstacle3D> obs = triangulize();

		int nVerts = 1;
		int nObjs = 0;
		std::string res;

		// write each obstacle
		for (const Obstacle3D& o : obs) {

			// write the vertices
			for (const Triangle3& t : o.triangles) {
				res += "v " + std::to_string(t.p1.x) + " " + std::to_string(t.p1.y) + " " + std::to_string(t.p1.z) + "\n";
				res += "v " + std::to_string(t.p2.x) + " " + std::to_string(t.p2.y) + " " + std::to_string(t.p2.z) + "\n";
				res += "v " + std::to_string(t.p3.x) + " " + std::to_string(t.p3.y) + " " + std::to_string(t.p3.z) + "\n";
			}

			// create a new group
			res += "g elem_" + std::to_string(++nObjs) + "\n";

			// write the group's faces
			for (size_t i = 0; i < o.triangles.size(); ++i) {
				res += "f " + std::to_string(nVerts+0) + " " + std::to_string(nVerts+1) + " " + std::to_string(nVerts+2) + "\n";
				nVerts += 3;
			}

		}

		// done
		return res;

	}

private:

	/** convert a floor (floor/ceiling) into triangles */
	Obstacle3D getTriangles(const Floorplan::Floor* f) {

		// 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)

		// TODO: variable type?
		Obstacle3D res(Floorplan::Material::CONCRETE);

		Polygon poly;

		// append all "add" and "remove" areas
		for (Floorplan::FloorOutlinePolygon* fop : f->outline) {
			switch (fop->method) {
				case Floorplan::OutlineMethod::ADD:		poly.add(fop->poly);	break;
				case Floorplan::OutlineMethod::REMOVE:	poly.remove(fop->poly);	break;
				default:								throw 1;
			}
		}

		// convert them into polygons
		std::vector<std::vector<Point3>> polys = poly.get(f->getStartingZ());

		// 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 for reflection to work with the correct normals
				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) {tria1 = tria1 - Point3(0,0,0.02);}
				if (tria2.getNormal().z < 0) {tria2 = tria2 - Point3(0,0,0.02);}

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

			}
		}

		return res;

	}

	/** convert a line obstacle to 3D triangles */
	Obstacle3D getTriangles(const Floorplan::Floor* f, const Floorplan::FloorObstacleLine* fol) {

		/*
		Obstacle3D res(fol->material);

		Point3 p1(fol->from.x, fol->from.y, f->getStartingZ());
		Point3 p2(fol->to.x, fol->to.y, f->getStartingZ());
		Point3 p3(fol->to.x, fol->to.y, f->getEndingZ());
		Point3 p4(fol->from.x, fol->from.y, f->getEndingZ());

		Triangle3 t1(p1,p2,p3);
		Triangle3 t2(p1,p3,p4);

		res.triangles.push_back(t1);
		res.triangles.push_back(t2);

		*/

		const float thickness_m = fol->thickness_m;
		const Point2 from = fol->from;
		const Point2 to = fol->to;
		const Point2 cen2 = (from+to)/2;

		const float rad = std::atan2(to.y - from.y, to.x - from.x);
		const float deg = rad * 180 / M_PI;

		// cube's destination center
		const Point3 pos(cen2.x, cen2.y, f->atHeight + f->height/2);

		// div by 2.01 to prevent overlapps and z-fi
		const float sx = from.getDistance(to) / 2.01f;
		const float sy = thickness_m / 2.01f;
		const float sz = f->height / 2.01f;	// prevent overlaps
		const Point3 size(sx, sy, sz);
		const Point3 rot(0,0,deg);

		// build
		Cube cube(pos, size, rot);

		// done
		Obstacle3D res(fol->material);
		res.triangles = cube.getTriangles();
		return res;

	}



};

#endif // MODELFACTORY_H