/*  ADMesh -- process triangulated solid meshes
 *  Copyright (C) 1995, 1996  Anthony D. Martin <amartin@engr.csulb.edu>
 *  Copyright (C) 2013, 2014  several contributors, see AUTHORS
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 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 General Public License for more details.

 *  You should have received a copy of the GNU General Public License along
 *  with this program; if not, write to the Free Software Foundation, Inc.,
 *  51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 *  Questions, comments, suggestions, etc to
 *           https://github.com/admesh/admesh/issues
 */

#ifndef __admesh_stl__
#define __admesh_stl__

#include <stdio.h>
#include <stdint.h>
#include <stddef.h>

#include <vector>
#include <Eigen/Geometry> 

// Size of the binary STL header, free form.
#define LABEL_SIZE             80
// Binary STL, length of the "number of faces" counter.
#define NUM_FACET_SIZE         4
// Binary STL, sizeof header + number of faces.
#define HEADER_SIZE            84
#define STL_MIN_FILE_SIZE      284
#define ASCII_LINES_PER_FACET  7

typedef Eigen::Matrix<float, 3, 1, Eigen::DontAlign> stl_vertex;
typedef Eigen::Matrix<float, 3, 1, Eigen::DontAlign> stl_normal;
typedef Eigen::Matrix<int,   3, 1, Eigen::DontAlign> stl_triangle_vertex_indices;
static_assert(sizeof(stl_vertex) == 12, "size of stl_vertex incorrect");
static_assert(sizeof(stl_normal) == 12, "size of stl_normal incorrect");

struct stl_facet {
	stl_normal normal;
	stl_vertex vertex[3];
	char       extra[2];

	stl_facet  rotated(const Eigen::Quaternion<float, Eigen::DontAlign> &rot) const {
		stl_facet out;
		out.normal    = rot * this->normal;
		out.vertex[0] = rot * this->vertex[0];
		out.vertex[1] = rot * this->vertex[1];
		out.vertex[2] = rot * this->vertex[2];
		return out;
	}
};

#define SIZEOF_STL_FACET       50

static_assert(offsetof(stl_facet, normal) == 0, "stl_facet.normal has correct offset");
static_assert(offsetof(stl_facet, vertex) == 12, "stl_facet.vertex has correct offset");
static_assert(offsetof(stl_facet, extra ) == 48, "stl_facet.extra has correct offset");
static_assert(sizeof(stl_facet) >= SIZEOF_STL_FACET, "size of stl_facet incorrect");

typedef enum {binary, ascii, inmemory} stl_type;

struct stl_neighbors {
  	stl_neighbors() { reset(); }
  	void reset() {
  		neighbor[0] = -1;
  		neighbor[1] = -1;
  		neighbor[2] = -1;
  		which_vertex_not[0] = -1;
  		which_vertex_not[1] = -1;
  		which_vertex_not[2] = -1;
  	}
  	int num_neighbors_missing() const { return (this->neighbor[0] == -1) + (this->neighbor[1] == -1) + (this->neighbor[2] == -1); }
  	int num_neighbors() const { return 3 - this->num_neighbors_missing(); }

  	// Index of a neighbor facet.
  	int   neighbor[3];
  	// Index of an opposite vertex at the neighbor face.
  	char  which_vertex_not[3];
};

struct stl_stats {
	stl_stats() { this->reset(); }
	void reset() { memset(this, 0, sizeof(stl_stats)); this->volume = -1.0; }
	char          header[81];
	stl_type      type;
	uint32_t      number_of_facets;
	stl_vertex    max;
	stl_vertex    min;
	stl_vertex    size;
	float         bounding_diameter;
	float         shortest_edge;
	float         volume;
	int           connected_edges;
	int           connected_facets_1_edge;
	int           connected_facets_2_edge;
	int           connected_facets_3_edge;
	int           facets_w_1_bad_edge;
	int           facets_w_2_bad_edge;
	int           facets_w_3_bad_edge;
	int           original_num_facets;
	int           edges_fixed;
	int           degenerate_facets;
	int           facets_removed;
	int           facets_added;
	int           facets_reversed;
	int           backwards_edges;
	int           normals_fixed;
	int           number_of_parts;
};

struct stl_file {
	stl_file() {}

	void clear() {
		this->facet_start.clear();
		this->neighbors_start.clear();
		this->stats.reset();
	}

	std::vector<stl_facet>     		facet_start;
	std::vector<stl_neighbors> 		neighbors_start;
	// Statistics
	stl_stats     					stats;
};

struct indexed_triangle_set
{
	indexed_triangle_set() {}

	void clear() { indices.clear(); vertices.clear(); }

	std::vector<stl_triangle_vertex_indices> 	indices;
	std::vector<stl_vertex>       				vertices;
	//FIXME add normals once we get rid of the stl_file from TriangleMesh completely.
	//std::vector<stl_normal> 					normals
};

extern bool stl_open(stl_file *stl, const char *file);
extern void stl_stats_out(stl_file *stl, FILE *file, char *input_file);
extern bool stl_print_neighbors(stl_file *stl, char *file);
extern bool stl_write_ascii(stl_file *stl, const char *file, const char *label);
extern bool stl_write_binary(stl_file *stl, const char *file, const char *label);
extern void stl_check_facets_exact(stl_file *stl);
extern void stl_check_facets_nearby(stl_file *stl, float tolerance);
extern void stl_remove_unconnected_facets(stl_file *stl);
extern void stl_write_vertex(stl_file *stl, int facet, int vertex);
extern void stl_write_facet(stl_file *stl, char *label, int facet);
extern void stl_write_neighbor(stl_file *stl, int facet);
extern bool stl_write_quad_object(stl_file *stl, char *file);
extern void stl_verify_neighbors(stl_file *stl);
extern void stl_fill_holes(stl_file *stl);
extern void stl_fix_normal_directions(stl_file *stl);
extern void stl_fix_normal_values(stl_file *stl);
extern void stl_reverse_all_facets(stl_file *stl);
extern void stl_translate(stl_file *stl, float x, float y, float z);
extern void stl_translate_relative(stl_file *stl, float x, float y, float z);
extern void stl_scale_versor(stl_file *stl, const stl_vertex &versor);
inline void stl_scale(stl_file *stl, float factor) { stl_scale_versor(stl, stl_vertex(factor, factor, factor)); }
extern void stl_rotate_x(stl_file *stl, float angle);
extern void stl_rotate_y(stl_file *stl, float angle);
extern void stl_rotate_z(stl_file *stl, float angle);
extern void stl_mirror_xy(stl_file *stl);
extern void stl_mirror_yz(stl_file *stl);
extern void stl_mirror_xz(stl_file *stl);

extern void stl_get_size(stl_file *stl);

template<typename T>
extern void stl_transform(stl_file *stl, T *trafo3x4)
{
	for (uint32_t i_face = 0; i_face < stl->stats.number_of_facets; ++ i_face) {
		stl_facet &face = stl->facet_start[i_face];
		for (int i_vertex = 0; i_vertex < 3; ++ i_vertex) {
			stl_vertex &v_dst = face.vertex[i_vertex];
			stl_vertex  v_src = v_dst;
			v_dst(0) = T(trafo3x4[0] * v_src(0) + trafo3x4[1] * v_src(1) + trafo3x4[2]  * v_src(2) + trafo3x4[3]);
			v_dst(1) = T(trafo3x4[4] * v_src(0) + trafo3x4[5] * v_src(1) + trafo3x4[6]  * v_src(2) + trafo3x4[7]);
			v_dst(2) = T(trafo3x4[8] * v_src(0) + trafo3x4[9] * v_src(1) + trafo3x4[10] * v_src(2) + trafo3x4[11]);
		}
		stl_vertex &v_dst = face.normal;
		stl_vertex  v_src = v_dst;
		v_dst(0) = T(trafo3x4[0] * v_src(0) + trafo3x4[1] * v_src(1) + trafo3x4[2]  * v_src(2));
		v_dst(1) = T(trafo3x4[4] * v_src(0) + trafo3x4[5] * v_src(1) + trafo3x4[6]  * v_src(2));
		v_dst(2) = T(trafo3x4[8] * v_src(0) + trafo3x4[9] * v_src(1) + trafo3x4[10] * v_src(2));
	}

	stl_get_size(stl);
}

template<typename T>
inline void stl_transform(stl_file *stl, const Eigen::Transform<T, 3, Eigen::Affine, Eigen::DontAlign>& t)
{
	const Eigen::Matrix<double, 3, 3, Eigen::DontAlign> r = t.matrix().template block<3, 3>(0, 0);
	for (size_t i = 0; i < stl->stats.number_of_facets; ++ i) {
		stl_facet &f = stl->facet_start[i];
		for (size_t j = 0; j < 3; ++j)
			f.vertex[j] = (t * f.vertex[j].template cast<T>()).template cast<float>().eval();
		f.normal = (r * f.normal.template cast<T>()).template cast<float>().eval();
	}

	stl_get_size(stl);
}

template<typename T>
inline void stl_transform(stl_file *stl, const Eigen::Matrix<T, 3, 3, Eigen::DontAlign>& m)
{
	for (size_t i = 0; i < stl->stats.number_of_facets; ++ i) {
		stl_facet &f = stl->facet_start[i];
		for (size_t j = 0; j < 3; ++j)
			f.vertex[j] = (m * f.vertex[j].template cast<T>()).template cast<float>().eval();
		f.normal = (m * f.normal.template cast<T>()).template cast<float>().eval();
	}

	stl_get_size(stl);
}


template<typename T>
extern void its_transform(indexed_triangle_set &its, T *trafo3x4)
{
	for (stl_vertex &v_dst : its.vertices) {
		stl_vertex  v_src = v_dst;
		v_dst(0) = T(trafo3x4[0] * v_src(0) + trafo3x4[1] * v_src(1) + trafo3x4[2]  * v_src(2) + trafo3x4[3]);
		v_dst(1) = T(trafo3x4[4] * v_src(0) + trafo3x4[5] * v_src(1) + trafo3x4[6]  * v_src(2) + trafo3x4[7]);
		v_dst(2) = T(trafo3x4[8] * v_src(0) + trafo3x4[9] * v_src(1) + trafo3x4[10] * v_src(2) + trafo3x4[11]);
	}
}

template<typename T>
inline void its_transform(indexed_triangle_set &its, const Eigen::Transform<T, 3, Eigen::Affine, Eigen::DontAlign>& t)
{
	const Eigen::Matrix<double, 3, 3, Eigen::DontAlign> r = t.matrix().template block<3, 3>(0, 0);
	for (stl_vertex &v : its.vertices)
		v = (t * v.template cast<T>()).template cast<float>().eval();
}

template<typename T>
inline void its_transform(indexed_triangle_set &its, const Eigen::Matrix<T, 3, 3, Eigen::DontAlign>& m)
{
	for (stl_vertex &v : its.vertices)
		v = (m * v.template cast<T>()).template cast<float>().eval();
}

extern void its_rotate_x(indexed_triangle_set &its, float angle);
extern void its_rotate_y(indexed_triangle_set &its, float angle);
extern void its_rotate_z(indexed_triangle_set &its, float angle);

extern void stl_generate_shared_vertices(stl_file *stl, indexed_triangle_set &its);
extern bool its_write_obj(const indexed_triangle_set &its, const char *file);
extern bool its_write_off(const indexed_triangle_set &its, const char *file);
extern bool its_write_vrml(const indexed_triangle_set &its, const char *file);

extern bool stl_write_dxf(stl_file *stl, const char *file, char *label);
inline void stl_calculate_normal(stl_normal &normal, stl_facet *facet) {
  normal = (facet->vertex[1] - facet->vertex[0]).cross(facet->vertex[2] - facet->vertex[0]);
}
inline void stl_normalize_vector(stl_normal &normal) {
  double length = normal.cast<double>().norm();
  if (length < 0.000000000001)
    normal = stl_normal::Zero();
  else
    normal *= float(1.0 / length);
}
extern void stl_calculate_volume(stl_file *stl);

extern void stl_repair(stl_file *stl, bool fixall_flag, bool exact_flag, bool tolerance_flag, float tolerance, bool increment_flag, float increment, bool nearby_flag, int iterations, bool remove_unconnected_flag, bool fill_holes_flag, bool normal_directions_flag, bool normal_values_flag, bool reverse_all_flag, bool verbose_flag);

extern void stl_allocate(stl_file *stl);
extern void stl_read(stl_file *stl, int first_facet, bool first);
extern void stl_facet_stats(stl_file *stl, stl_facet facet, bool &first);
extern void stl_reallocate(stl_file *stl);
extern void stl_add_facet(stl_file *stl, const stl_facet *new_facet);

// Validate the mesh, assert on error.
extern bool stl_validate(const stl_file *stl);
extern bool stl_validate(const stl_file *stl, const indexed_triangle_set &its);

#endif