#include "../ifcgeom_schema_agnostic/IfcGeomRenderStyles.h"

#include <boost/property_tree/json_parser.hpp>
#include <boost/property_tree/ptree.hpp>

#include <map>
#include <mutex>

namespace pt = boost::property_tree;

static std::map<std::string, IfcGeom::SurfaceStyle> default_materials;
static IfcGeom::SurfaceStyle default_material;
static bool default_materials_initialized = false;

void InitDefaultMaterials() {
	default_materials.insert(std::make_pair("IfcSite", IfcGeom::SurfaceStyle("IfcSite")));
	default_materials["IfcSite"].Diffuse().reset(IfcGeom::SurfaceStyle::ColorComponent(0.75, 0.8, 0.65));

	default_materials.insert(std::make_pair("IfcSlab", IfcGeom::SurfaceStyle("IfcSlab")));
	default_materials["IfcSlab"].Diffuse().reset(IfcGeom::SurfaceStyle::ColorComponent(0.4, 0.4, 0.4));

	default_materials.insert(std::make_pair("IfcWallStandardCase", IfcGeom::SurfaceStyle("IfcWallStandardCase")));
	default_materials["IfcWallStandardCase"].Diffuse().reset(IfcGeom::SurfaceStyle::ColorComponent(0.9, 0.9, 0.9));

	default_materials.insert(std::make_pair("IfcWall", IfcGeom::SurfaceStyle("IfcWall")));
	default_materials["IfcWall"].Diffuse().reset(IfcGeom::SurfaceStyle::ColorComponent(0.9, 0.9, 0.9));

	default_materials.insert(std::make_pair("IfcWindow", IfcGeom::SurfaceStyle("IfcWindow")));
	default_materials["IfcWindow"].Diffuse().reset(IfcGeom::SurfaceStyle::ColorComponent(0.75, 0.8, 0.75));
	default_materials["IfcWindow"].Transparency().reset(0.3);

	default_materials.insert(std::make_pair("IfcDoor", IfcGeom::SurfaceStyle("IfcDoor")));
	default_materials["IfcDoor"].Diffuse().reset(IfcGeom::SurfaceStyle::ColorComponent(0.55, 0.3, 0.15));

	default_materials.insert(std::make_pair("IfcBeam", IfcGeom::SurfaceStyle("IfcBeam")));
	default_materials["IfcBeam"].Diffuse().reset(IfcGeom::SurfaceStyle::ColorComponent(0.75, 0.7, 0.7));

	default_materials.insert(std::make_pair("IfcRailing", IfcGeom::SurfaceStyle("IfcRailing")));
	default_materials["IfcRailing"].Diffuse().reset(IfcGeom::SurfaceStyle::ColorComponent(0.65, 0.6, 0.6));

	default_materials.insert(std::make_pair("IfcMember", IfcGeom::SurfaceStyle("IfcMember")));
	default_materials["IfcMember"].Diffuse().reset(IfcGeom::SurfaceStyle::ColorComponent(0.65, 0.6, 0.6));

	default_materials.insert(std::make_pair("IfcPlate", IfcGeom::SurfaceStyle("IfcPlate")));
	default_materials["IfcPlate"].Diffuse().reset(IfcGeom::SurfaceStyle::ColorComponent(0.8, 0.8, 0.8));

	default_materials.insert(std::make_pair("IfcSpace", IfcGeom::SurfaceStyle("IfcSpace")));
	default_materials["IfcWindow"].Diffuse().reset(IfcGeom::SurfaceStyle::ColorComponent(0.65, 0.75, 0.8));
	default_materials["IfcWindow"].Transparency().reset(0.8);

	default_material = IfcGeom::SurfaceStyle("DefaultMaterial");
	default_material.Diffuse().reset(IfcGeom::SurfaceStyle::ColorComponent(0.7, 0.7, 0.7));

	default_materials_initialized = true;
}

boost::optional<IfcGeom::SurfaceStyle::ColorComponent> read_colour_component(const boost::optional<pt::ptree&> list) {
	if (!list) {
		return boost::none;
	}
	double rgb[3];
	int i = 0;
	for (pt::ptree::value_type &colour : list.get()) {
		if (3 <= i) {
			throw std::runtime_error("rgb array over 3 elements large");
		}
		rgb[i] = colour.second.get_value<double>();
		i++;
	}
	if (i != 3) {
		throw std::runtime_error("rgb array less than 3 elements large (was " + std::to_string(i) + ")");
	}
	return IfcGeom::SurfaceStyle::ColorComponent(rgb[0], rgb[1], rgb[2]);
}

void IfcGeom::set_default_style_file(const std::string& json_file) {
	if (!default_materials_initialized) InitDefaultMaterials();
	default_materials.clear();

	// @todo this will probably need to be updated for UTF-8 paths on Windows
	pt::ptree root;
	pt::read_json(json_file, root);

	for (pt::ptree::value_type &material_pair : root) {
		std::string name = material_pair.first;
		default_materials.insert(std::make_pair(name, IfcGeom::SurfaceStyle(name)));

		pt::ptree material = material_pair.second;
		boost::optional<pt::ptree&> diffuse = material.get_child_optional("diffuse");
		default_materials[name].Diffuse() = read_colour_component(diffuse);

		boost::optional<pt::ptree&> specular = material.get_child_optional("specular");
		default_materials[name].Specular() = read_colour_component(specular);

		if (material.get_child_optional("specular-roughness")) {
			default_materials[name].Specularity().reset(1.0 / material.get<double>("specular-roughness"));
		}
		if (material.get_child_optional("transparency")) {
			default_materials[name].Transparency() = material.get<double>("transparency");
		}
	}

	// Is "*" present? If yes, remove it and make it the default style.
	std::map<std::string, IfcGeom::SurfaceStyle>::const_iterator it = default_materials.find("*");
	if (it != default_materials.end()) {
		IfcGeom::SurfaceStyle star = it->second;
		default_material.Diffuse() = star.Diffuse();
		default_material.Specular() = star.Specular();
		default_material.Specularity() = star.Specularity();
		default_material.Transparency() = star.Transparency();
		default_materials.erase(it);
	}
}

const IfcGeom::SurfaceStyle* IfcGeom::get_default_style(const std::string& s) {
	static std::mutex m;
	std::lock_guard<std::mutex> lk(m);

	if (!default_materials_initialized) InitDefaultMaterials();
	std::map<std::string, IfcGeom::SurfaceStyle>::const_iterator it = default_materials.find(s);
	if (it == default_materials.end()) {
		default_materials.insert(std::make_pair(s, IfcGeom::SurfaceStyle(s)));
		default_materials[s].Diffuse() = default_material.Diffuse();
		default_materials[s].Specular() = default_material.Specular();
		default_materials[s].Specularity() = default_material.Specularity();
		default_materials[s].Transparency() = default_material.Transparency();
		it = default_materials.find(s);
	}
	const IfcGeom::SurfaceStyle& surface_style = it->second;
	return &surface_style;
}

IfcGeom::SurfaceStyle& IfcGeom::update_default_style(const std::string& s) {
	if (!default_materials_initialized) InitDefaultMaterials();
	std::map<std::string, IfcGeom::SurfaceStyle>::iterator it = default_materials.find(s);
	if (it == default_materials.end()) {
		throw std::runtime_error("No style registered for " + s);
	}
	return it->second;
}