/*
   render/model.h
   This file is part of the Osirion project and is distributed under
   the terms of the GNU General Public License version 2
*/

#include <iostream>
#include <string>
#include <fstream>
#include <iomanip>
#include <sstream>
#include <vector>
#include <list>

#include "core/cvar.h"
#include "core/model.h"
#include "filesystem/filesystem.h"

namespace core
{

const float MAX_BOUNDS = 8192;
const float delta = 10e-10;

const size_t VERTEXARRAYVERTEXARRAYSIZE=65536*3;

/* ---------- core::VertexArray ------------------------------------  */
float VertexArray::vertex[VERTEXARRAYSIZE];
float VertexArray::vertex_color[VERTEXARRAYSIZE];
float VertexArray::vertex_normal[VERTEXARRAYSIZE];

float VertexArray::evertex[VERTEXARRAYSIZE];
float VertexArray::evertex_normal[VERTEXARRAYSIZE];

size_t VertexArray::vertex_index;
size_t VertexArray::evertex_index;

void VertexArray::clear()
{
	memset(vertex, 0, sizeof(vertex));
	memset(vertex_color, 0, sizeof(vertex_color));
	memset(vertex_normal, 0, sizeof(vertex_normal));

	memset(evertex, 0, sizeof(evertex));
	memset(evertex_normal, 0, sizeof(evertex_normal));

	vertex_index = 0;
	evertex_index = 0;
}

void VertexArray::add_vertex(math::Vector3f const &v, math::Vector3f const &n, math::Color const &color) {
	if (vertex_index + 3 >= VERTEXARRAYSIZE) {
		con_warn << "VertexArray overflow!" << std::endl;
		return;
	}

	for (int i = 0; i < 3; i ++) {
		vertex[vertex_index+i] = v[i];
		vertex_normal[vertex_index+i] = n[i];
	}

	vertex_color[vertex_index] = color.r;
	vertex_color[vertex_index+1] = color.g;
	vertex_color[vertex_index+2] = color.b;

	vertex_index += 3;
}

void VertexArray::add_evertex(math::Vector3f const &v, math::Vector3f const &n) {
	if (evertex_index + 3 >= VERTEXARRAYSIZE) {
		con_warn << "EVertexArray overflow!" << std::endl;
		return;
	}

	for (int i = 0; i < 3; i ++) {
		evertex[evertex_index+i] = v[i];
		evertex_normal[evertex_index+i] = n[i];
	}

	evertex_index += 3;
}

/* ---------- core::Light ------------------------------------------  */

Light::Light(math::Vector3f const & location, math::Color const & color) :
	light_location(location),
	light_color(color)
{}

Light::~Light()
{}

/* ---------- core::Engine ------------------------------------------  */

Engine::Engine(math::Vector3f const & location) :
		engine_location(location)
{}

Engine::~Engine()
{}

/* ---------- core::Model ------------------------------------------  */

std::map<std::string, Model*> Model::registry;

Model::Model(std::string const & name) :
		model_name(name)
{
	model_valid = false;
	model_scale = 1.0f / 1024.0f;
	model_first_vertex = 0;
	model_first_evertex = 0;
	model_vertex_count = 0;
	model_evertex_count = 0;
	
	std::string fn("maps/");
	fn.append(name);
	fn.append(".map");
	filesystem::File *f = filesystem::open(fn.c_str());
	
	if (!f) {
		return;
	}
	
	fn = f->path();
	fn.append(f->name());
	filesystem::close(f);
	
	std::ifstream ifs(fn.c_str());
	if (!ifs.is_open()) {
		con_warn << "Could not stream " << fn << "!\n";
		return;
	}
	
	// --------- the actual reading
	using math::Vector3f;
	using math::Plane3f;
	
	std::vector<Plane3f *> 	planes;
	unsigned int 		level = 0;
	char 			data[1024];
	
	std::string 		class_name;
	math::Vector3f 		class_origin;
	float 			class_angle;
	math::Color		class_color;

	model_first_evertex = VertexArray::evertex_index/3;
	model_first_vertex = VertexArray::vertex_index/3;
	
	while (ifs) {
		ifs.getline(data, 1023);
		std::istringstream linestream(data);
		std::string firstword;
		
		if (linestream >> firstword) {
			if (firstword == "//") {
				//cout << "   COMMENT!" << std::endl;
				continue;
			} else if (firstword == "{") {
				if (!level) {
					class_angle = 0;
					class_name.clear();
					class_origin = math::Vector3f(0,0,0);
					class_color = math::Color(1, 1, 1);
				}
				level ++;
				//cout << "   LEVEL +" << level << std::endl;
			} else if (firstword == "}") {
				//cout << "   LEVEL -" << level << std::endl;
				if ((level == 2) && (class_name == "worldspawn")) {

					if (!(Cvar::sv_dedicated && Cvar::sv_dedicated->value())) {
						// for every face
						std::vector<Vector3f *>points;
						for (std::vector<Plane3f *>::iterator face = planes.begin(); face != planes.end(); face++) {
							make_face((*face), planes);
						}
					}

					// clean planes
					for (std::vector<Plane3f *>::iterator it = planes.begin(); it != planes.end(); it++) {
						delete(*it);
					}
					planes.clear();
					
				} else if ((level == 1) && (class_name == "target_engine")) {
					//con_debug << "  engine  at " << class_origin << "\n";
					add_engine(new Engine(class_origin * model_scale));
				} else if ((level == 1) && (class_name == "light")) {
					add_light(new Light(class_origin * model_scale, class_color));
				}
				
				if (level == 1) {
					class_angle = 0;
					class_name.clear();
					class_origin = Vector3f(0,0,0);
				}
				
				level--;
				
			} else if (firstword == "\"classname\"") {
				class_name.clear();
				if (linestream >> class_name) {
					if (class_name.size() > 2) {
						class_name.erase(0,1);
						class_name.erase(class_name.size()-1, 1);
						//linestream >> class_name;
						//con_debug << "   classname '" << class_name << "'" << std::endl;
					} else {
						class_name.clear();
					}
				} else {
					//cout << "   EMPTY CLASS" << std::endl;
				}
			} else if (firstword == "\"origin\"") {
				std::string tmp;
				char c;
				while ((linestream.get(c)) && (c != '"'));
				while ((linestream.get(c)) && (c != '"'))
					tmp += c;
				std::istringstream is(tmp);
				is >> class_origin.x;
				is >> class_origin.y;
				is >> class_origin.z;
				//con_debug << "   origin '" << class_origin << "'" << std::endl;

			} else if (firstword == "\"_color\"") {
				std::string tmp;
				char c;
				while ((linestream.get(c)) && (c != '"'));
				while ((linestream.get(c)) && (c != '"'))
					tmp += c;
				std::istringstream is(tmp);
				is >> class_color.r;
				is >> class_color.g;
				is >> class_color.b;

			} else if (firstword == "\"angle\"") {
				std::string tmp;
				char c;
				while ((linestream.get(c)) && (c != '"'));
				while ((linestream.get(c)) && (c != '"'))
					tmp += c;
				std::istringstream is(tmp);
				is >> class_angle;
				//con_debug << "   angle '" << class_angle << "'" << std::endl;

			} else if (firstword == "(") {
				if ((level == 2) && (class_name == "worldspawn")) {
					//cout << "   BRUSH PLANE" << std::endl;
					Vector3f p1;
					Vector3f p2;
					Vector3f p3;
					std::string tmp;
					std::string texture;
					
					linestream >> p1;
					linestream >> tmp; // )
					linestream >> tmp; // (
					linestream >> p2;
					linestream >> tmp; // )
					linestream >> tmp; // (
					linestream >> p3;
					linestream >> tmp; // )
					linestream >> texture;
					
					//cout << data << std::endl;
					//cout << "(" << p1 << ") (" <<  p2 << ") (" << p3 << ") " << texture << std::endl;
					
					Plane3f *plane = new Plane3f(p1, p2, p3);
					plane->texture() = texture;
					planes.push_back(plane);
					//cout << "normal " << plane->normal() << std::endl;
				} else {
					//cout << "   UNKNOWN line for '" << classname << "' level " << level << std::endl;
				}
			}
		}
	}
	
	ifs.close();
	
	if ((model_vertex_count + model_evertex_count) > 0 ) {
		if (model_maxbbox.lengthsquared() > model_minbbox.lengthsquared()) {
			model_radius = model_maxbbox.length();
		} else {
			model_radius = model_minbbox.length();
		}
		model_valid = true;
	}
	//con_debug << "  maps/" << name << ".map " << model_face.size() << " polygons\n";
	con_debug  << "  maps/" << name << ".map " << (model_vertex_count + model_evertex_count)/3 << " triangles" << std::endl;
}

Model::~Model()
{
	// delete all engines
	for (std::list<Engine *>::iterator eit = model_engine.begin(); eit != model_engine.end(); eit++) {
		delete(*eit);
	}
	model_engine.clear();
	
	// delete all lights
	for (std::list<Light *>::iterator lit = model_light.begin(); lit != model_light.end(); lit++) {
		delete (*lit);
	}
	model_light.clear();
}

void Model::make_face(math::Plane3f *face, std::vector<math::Plane3f *> & planes)
{
	using math::Vector3f;
	using math::Plane3f;
	
	// ignore caulk
	if (face->texture() == "common/caulk") {
		return;
	}
	
	// using suggestions from
	// http://www.flipcode.com/archives/Level_Editing.shtml
	
	std::vector<math::Vector3f *> vl;
	
	// inital vertexes
	
	// check if the face is x-axis oriented
	if ((fabsf(face->normal().x) >= fabsf(face->normal().y)) && (fabsf(face->normal().x) >=  fabsf(face->normal().z))) {
		//cout << "  x oriented" << std::endl;
		
		if (face->normal().x >= 0) {
			vl.push_back(new math::Vector3f(0, -MAX_BOUNDS, -MAX_BOUNDS));
			vl.push_back(new math::Vector3f(0, -MAX_BOUNDS, MAX_BOUNDS));
			vl.push_back(new math::Vector3f(0, MAX_BOUNDS, MAX_BOUNDS));
			vl.push_back(new math::Vector3f(0, MAX_BOUNDS, -MAX_BOUNDS));
		} else {
			vl.push_back(new math::Vector3f(0, MAX_BOUNDS, -MAX_BOUNDS));
			vl.push_back(new math::Vector3f(0, MAX_BOUNDS, MAX_BOUNDS));
			vl.push_back(new math::Vector3f(0, -MAX_BOUNDS, MAX_BOUNDS));
			vl.push_back(new math::Vector3f(0, -MAX_BOUNDS, -MAX_BOUNDS));
		}
		// calculate the x coordinate of each face vertex
		for (std::vector<Vector3f *>::iterator it = vl.begin(); it != vl.end(); it++) {
			(*it)->x = (-face->d() -
				    face->normal().z * (*it)->z -
				    face->normal().y * (*it)->y) /
				   face->normal().x;
		}
	}
	
	// check if the face is y-axis oriented
	else if ((fabsf(face->normal().y) >= fabsf(face->normal().x)) && (fabsf(face->normal().y) >=  fabsf(face->normal().z))) {
		//cout << "  y oriented" << std::endl;
		
		if (face->normal().y >= 0) {
			vl.push_back(new Vector3f(MAX_BOUNDS, 0, -MAX_BOUNDS));
			vl.push_back(new Vector3f(MAX_BOUNDS, 0, MAX_BOUNDS));
			vl.push_back(new Vector3f(-MAX_BOUNDS, 0, MAX_BOUNDS));
			vl.push_back(new Vector3f(-MAX_BOUNDS, 0, -MAX_BOUNDS));
		} else {
			vl.push_back(new Vector3f(-MAX_BOUNDS, 0, -MAX_BOUNDS));
			vl.push_back(new Vector3f(-MAX_BOUNDS, 0, MAX_BOUNDS));
			vl.push_back(new Vector3f(MAX_BOUNDS, 0, MAX_BOUNDS));
			vl.push_back(new Vector3f(MAX_BOUNDS, 0, -MAX_BOUNDS));
		}
		
		// calculate the x coordinate of each face vertex
		for (std::vector<Vector3f *>::iterator it = vl.begin(); it != vl.end(); it++) {
			(*it)->y = (-face->d() -
				    face->normal().z * (*it)->z -
				    face->normal().x * (*it)->x) /
				   face->normal().y;
		}
	}
	
	// face must be z-axis oriented
	else {
		//cout << "  z oriented" << std::endl;
		if (face->normal().z >= 0) {
			vl.push_back(new Vector3f(-MAX_BOUNDS, -MAX_BOUNDS, 0));
			vl.push_back(new Vector3f(-MAX_BOUNDS, MAX_BOUNDS, 0));
			vl.push_back(new Vector3f(MAX_BOUNDS, MAX_BOUNDS, 0));
			vl.push_back(new Vector3f(MAX_BOUNDS, -MAX_BOUNDS, 0));
		} else {
			vl.push_back(new Vector3f(MAX_BOUNDS, -MAX_BOUNDS, 0));
			vl.push_back(new Vector3f(MAX_BOUNDS, MAX_BOUNDS, 0));
			vl.push_back(new Vector3f(-MAX_BOUNDS, MAX_BOUNDS, 0));
			vl.push_back(new Vector3f(-MAX_BOUNDS, -MAX_BOUNDS, 0));
		}
		
		// calculate the x coordinate of each face vertex
		for (std::vector<Vector3f *>::iterator it = vl.begin(); it != vl.end(); it++) {
			(*it)->z = (-face->d() -
				    face->normal().x * (*it)->x -
				    face->normal().y * (*it)->y) /
				   face->normal().z;
		}
	}
	
	
	// intersect the face with every plane
	for (std::vector<Plane3f *>::iterator pit = planes.begin(); pit != planes.end(); pit++) {
		Plane3f *plane = (*pit);
		if (plane == face) {
			continue;
		}
		
		Vector3f fn = crossproduct(face->point(1)-face->point(0), face->point(2)-face->point(0));
		Vector3f pn = crossproduct(plane->point(1)-plane->point(0), plane->point(2)-plane->point(0));
		
		Vector3f t = crossproduct(fn, pn);
		if ((t.x == 0)  && (t.y == 0) && (t.z == 0)) {
			continue;
		}
		
		//cout << "  intersecting with plane with normal " << plane->normal() << std::endl;
	
		// intersect face with plane
		for (int i=0; vl.size() - i > 0; i++) {
		
			Vector3f v(*vl.at(i));
			
			
			Vector3f next;
			if (vl.size() - i > 1) {
				//cout << " -- at " << i+1 << std::endl;
				next = *vl.at(i+1);
			} else {
				next = *vl.front();
			}
			
			Vector3f prev;
			if (i > 0) {
				//cout << " -- at " << i-1 << std::endl;
				prev = *vl.at(i-1);
			} else {
				prev = *vl.back();
			}
			
			//cout << " vertex " << i << " prev " << prev << " v " << v << " next " << next << std::endl;
			if ((v.x*plane->normal().x + v.y*plane->normal().y + v.z*plane->normal().z +plane->d()) < delta) {
			
				// find current
				std::vector<Vector3f *>::iterator vit = vl.begin();
				while ((*vit) != vl.at(i)) {
					vit++;
				}
				
				// check if prev - v intersects with plane
				if ((prev.x*plane->normal().x + prev.y*plane->normal().y + prev.z*plane->normal().z + plane->d()) > -delta) {
				
					// calculate intersection
					float t1 = -plane->normal().x * prev.x - plane->normal().y * prev.y - plane->normal().z * prev.z -plane->d();
					float t2 = (plane->normal().x * v.x - plane->normal().x * prev.x +
						    plane->normal().y * v.y - plane->normal().y * prev.y +
						    plane->normal().z * v.z - plane->normal().z * prev.z);
					//cout << "prev t2 " << t2 << std::endl;
					Vector3f *s = new Vector3f;
					
					if (t2 == 0) {
						*s = v;
					} else {
						for (int j = 0; j < 3; j++)
							(*s)[j] = prev [j] + t1 * (v[j] - prev[j]) / t2;
					}
					
					//cout << "  added " << *s << std::endl;
					vit = vl.insert(vit,s);
					vit++;
					i++;
				}
				
				// check if next - v intersects with plane
				if ((next.x*plane->normal().x +  next.y*plane->normal().y + next.z*plane->normal().z + plane->d()) > -delta) {
					// calculate intersection
					
					// calculate intersection
					float t1 = -plane->normal().x * v.x - plane->normal().y * v.y - plane->normal().z * v.z -plane->d();
					float t2 = (plane->normal().x * next.x - plane->normal().x * v.x +
						    plane->normal().y * next.y - plane->normal().y * v.y +
						    plane->normal().z * next.z - plane->normal().z * v.z);
					//cout << "next t2 " << t2 << std::endl;
					Vector3f *s = new Vector3f;
					
					if (t2 == 0) {
						*s = v;
					} else {
						for (int j = 0; j < 3; j++)
							(*s)[j] = v [j] + t1 * (next[j] - v[j]) / t2;
					}
					
					//cout << "  added " << *s << std::endl;
					vit = vl.insert(vit,s);
					vit++;
					i++;
				}
				
				// erase
				delete *vit;
				vl.erase(vit);
				i--;
			}
			
		}
	}
	
	if (vl.size() > 2) {
	
		math::Color *color = 0;
		if (face->texture() == "colors/white") {
			color = new math::Color(1, 1, 1);
		} else if (face->texture() == "colors/grey90") {
			color = new math::Color(0.9, 0.9, 0.9);
		} else if (face->texture() == "colors/grey75") {
			color = new math::Color(0.75, 0.75, 0.75);
		} else if (face->texture() == "colors/grey50") {
			color = new math::Color(0.5, 0.5, 0.5);
		} else if (face->texture() == "colors/grey25") {
			color = new math::Color(0.25, 0.25, 0.25);
		} else if (face->texture() == "colors/black") {
			color = new math::Color(0, 0, 0);
		} else if (face->texture() == "common/entity") {
			color = 0;
		} else
			color = new math::Color(1.0f, 0.0, 1.0f);
	
		// calculate bounding box
		for (std::vector<Vector3f *>::iterator it = vl.begin(); it != vl.end(); it++) {	

			*(*it) *= model_scale;

			for (int i=0; i < 3; i++) {
				if (model_maxbbox[i] < (*(*it))[i])
					model_maxbbox[i] = (*(*it))[i];

				if (model_minbbox[i] > (*(*it))[i])
					model_minbbox[i] = (*(*it))[i];
			}
		}

		// split face into triangles
		while (vl.size() >2 ) {
			std::vector<Vector3f *>::iterator v0 = vl.begin();
			std::vector<Vector3f *>::reverse_iterator vn = vl.rbegin();
			std::vector<Vector3f *>::reverse_iterator vn1 = vl.rbegin();
			++vn1;
			
			Vector3f n(face->normal()*-1);
			n.normalize();

			if (!color) {
				VertexArray::add_evertex(*(*vn1), n);
				VertexArray::add_evertex(*(*vn), n);
				VertexArray::add_evertex(*(*v0), n);
				model_evertex_count += 3;
			} else {
				VertexArray::add_vertex(*(*vn1), n, *color);
				VertexArray::add_vertex(*(*vn), n, *color);
				VertexArray::add_vertex(*(*v0), n, *color);
				model_vertex_count += 3;
			}
		
			delete (*vn);
			vl.pop_back();
		}
		//add_face(mf);
		if (color) delete color;
	} else {
		con_debug << "Unresolved face!\n";
	}
	
	for (std::vector<Vector3f *>::iterator it = vl.begin(); it != vl.end(); it++) {
		delete(*it);
	}
	
	vl.clear();
	
}

void Model::add_engine(Engine *engine)
{
	model_engine.push_back(engine);
}

void Model::add_light(Light *light)
{
	model_light.push_back(light);
}

Model *Model::find(std::string const & name)
{
	std::map<std::string, Model*>::iterator it = registry.find(name);
	if (it == registry.end())
		return 0;
	else
		return (*it).second;
}

Model *Model::get(std::string const & name)
{
	Model *model = find(name);
	if (!model) {
		model = new Model(name);
		registry[model->name()] = model;
	}
	return model;
}

void Model::clear()
{
	// delete all models in the registry
	for (std::map<std::string, Model*>::iterator mit = registry.begin(); mit != registry.end(); mit++) {
		delete(*mit).second;
	}
	registry.clear();

	// clear the vertex array
	VertexArray::clear();
}

void Model::list()
{
	for (std::map<std::string, Model*>::iterator mit = registry.begin(); mit != registry.end(); mit++) {
		con_print << "  " << (*mit).second->name() << " "
			<< ((*mit).second->vertex_count() + (*mit).second->evertex_count())/3 << " triangles "
			<< (*mit).second->model_engine.size() << " engines "
			<< (*mit).second->model_light.size() << " lights\n";
	}
	con_print << registry.size() << " registered models" << std::endl;
	con_print << "vertex/evertex array usage " << (VertexArray::vertex_index * 100) / VERTEXARRAYSIZE << "%/" <<
		(VertexArray::evertex_index * 100) / VERTEXARRAYSIZE << "%\n";
}
}