#include "../ifcparse/IfcLogger.h"
#include "taxonomy.h"
#include "profile_helper.h"

using namespace ifcopenshell::geometry::taxonomy;

namespace {
	bool compare(const trimmed_curve& a, const trimmed_curve& b);

	bool compare(const collection& a, const collection& b);

	bool compare(const loop& a, const loop& b);

	bool compare(const face& a, const face& b);

	bool compare(const shell& a, const shell& b);

	bool compare(const solid& a, const solid& b);

	bool compare(const loft& a, const loft& b);

	bool compare(const boolean_result& a, const boolean_result& b);

	template <typename T>
	bool compare(const eigen_base<T>& t, const eigen_base<T>& u) {
		if (t.components_ == nullptr && u.components_ == nullptr) {
			return false;
		}
		else if (t.components_ == nullptr && u.components_ != nullptr) {
			return true;
		}
		else if (t.components_ != nullptr && u.components_ == nullptr) {
			return false;
		}

		auto t_begin = t.components_->data();
		auto t_end = t.components_->data() + t.components_->size();

		auto u_begin = u.components_->data();
		auto u_end = u.components_->data() + u.components_->size();

		return std::lexicographical_compare(t_begin, t_end, u_begin, u_end);
	}

	bool compare(const line& a, const line& b) {
		return compare(*a.matrix, *b.matrix);
	}

	bool compare(const plane& a, const plane& b) {
		return compare(*a.matrix, *b.matrix);
	}

	bool compare(const circle& a, const circle& b) {
		if (a.radius == b.radius) {
			return compare(*a.matrix, *b.matrix);
		}
		return a.radius < b.radius;
	}

	bool compare(const ellipse& a, const ellipse& b) {
		if (a.radius == b.radius && a.radius2 == b.radius2) {
			return compare(*a.matrix, *b.matrix);
		}
		return
			std::tie(a.radius, a.radius2) <
			std::tie(b.radius, b.radius2);
	}

	bool compare(const bspline_curve&, const bspline_curve&) {
		throw std::runtime_error("not implemented");
	}

	template <typename T>
	typename std::enable_if<std::is_base_of<item, T>::value, int>::type less_to_order(const T& a, const T& b) {
		const bool a_lt_b = compare(a, b);
		const bool b_lt_a = compare(b, a);
		return a_lt_b ?
			-1 : (!b_lt_a ? 0 : 1);
	}

	template <typename T>
	typename std::enable_if<!std::is_base_of<item, T>::value, int>::type less_to_order(const T& a, const T& b) {
		const bool a_lt_b = a < b;
		const bool b_lt_a = b < a;
		return a_lt_b ?
			-1 : (!b_lt_a ? 0 : 1);
	}

	template <typename T>
	int less_to_order_optional(const boost::optional<T>& a, const boost::optional<T>& b) {
		if (a && b) {
			return less_to_order(*a, *b);
		}
		else if (!a && !b) {
			return 0;
		}
		else if (a) {
			return 1;
		}
		else {
			return -1;
		}
	}

	int compare(const boost::variant<boost::blank, point3::ptr, double>& a, const boost::variant<boost::blank, point3::ptr, double>& b) {
		bool a_lt_b, b_lt_a;
		if (a.which() == 0) {
			return 0;
		} else if (a.which() == 1) {
			a_lt_b = compare(*boost::get<point3::ptr>(a), *boost::get<point3::ptr>(b));
			b_lt_a = compare(*boost::get<point3::ptr>(b), *boost::get<point3::ptr>(a));
		} else {
			a_lt_b = std::less<double>()(boost::get<double>(a), boost::get<double>(b));
			b_lt_a = std::less<double>()(boost::get<double>(b), boost::get<double>(a));
		}
		return a_lt_b ?
			-1 : (!b_lt_a ? 0 : 1);
	}

	bool compare(const extrusion& a, const extrusion& b) {
		// @todo extrusions can also have non-identity matrices right? perhaps it's time
		//       for a dedicated transform node and not on the abstract geom_item.
		const int order[3] = {
			less_to_order(a.basis, b.basis),
			less_to_order(a.direction, b.direction),
			a.depth < b.depth ? -1 : (a.depth == b.depth ? 0 : 1)
		};
		auto it = std::find_if(std::begin(order), std::end(order), [](int x) { return x; });
		if (it == std::end(order)) return false;
		return *it == -1;
	}

	bool compare(const node&, const node&) {
		throw std::runtime_error("not implemented");
	}

	bool compare(const offset_curve&, const offset_curve&) {
		throw std::runtime_error("not implemented");
	}

	bool compare(const revolve&, const revolve&) {
		throw std::runtime_error("not implemented");
	}

	bool compare(const bspline_surface&, const bspline_surface&) {
		throw std::runtime_error("not implemented");
	}

	bool compare(const cylinder&, const cylinder&) {
		throw std::runtime_error("not implemented");
	}

	bool compare(const sphere&, const sphere&) {
		throw std::runtime_error("not implemented");
	}

	bool compare(const torus&, const torus&) {
		throw std::runtime_error("not implemented");
	}

	bool compare(const sweep_along_curve&, const sweep_along_curve&) {
		throw std::runtime_error("not implemented");
	}

	bool compare(const piecewise_function&, const piecewise_function&) {
		throw std::runtime_error("not implemented");
	}

	bool compare(const style& a, const style& b) {
		const int order[5] = {
			less_to_order(a.name, b.name),
			less_to_order(a.diffuse, b.diffuse),
			less_to_order(a.specular, b.specular),
			less_to_order(a.specularity, b.specularity),
			less_to_order(a.transparency, b.transparency)
		};
		auto it = std::find_if(std::begin(order), std::end(order), [](int x) { return x; });
		if (it == std::end(order)) return false;
		return *it == -1;
	}

	/* A compile-time for loop over the taxonomy kinds */
	template <size_t N>
	struct dispatch_comparison {
		static bool dispatch(const item* a, const item* b) {
			if (N == a->kind() && N == b->kind()) {
				auto A = static_cast<const type_by_kind::type<N>*>(a);
				auto B = static_cast<const type_by_kind::type<N>*>(b);
				return compare(*A, *B);
			}
			else {
				return dispatch_comparison<N + 1>::dispatch(a, b);
			}
		}
	};

	template <>
	struct dispatch_comparison<type_by_kind::max> {
		static bool dispatch(const item*, const item*) {
			return false;
		}
	};
}

bool ifcopenshell::geometry::taxonomy::less(item::const_ptr a, item::const_ptr b) {
	if (a == b) {
		return false;
	}

	int a_kind = a->kind();
	int b_kind = b->kind();

	if (a_kind != b_kind) {
		return a_kind < b_kind;
	}

#ifdef TAXONOMY_USE_SHARED_PTR
	return dispatch_comparison<0>::dispatch(a.get(), b.get());
#endif
}


namespace {
	bool compare(const trimmed_curve& a, const trimmed_curve& b) {
		int a_which_start = a.start.which();
		int a_which_end = a.end.which();
		int b_which_start = b.start.which();
		int b_which_end = b.end.which();
		if (std::tie(a.orientation, a_which_start, a_which_end) ==
			std::tie(b.orientation, b_which_start, b_which_end)) {

			int start_state = compare(a.start, b.start);

			if (start_state == 0) {

				int end_state = compare(a.end, b.end);

				if (end_state == 0) {

					int a_has_basis = !!a.basis;
					int b_has_basis = !!a.basis;

					if (a_has_basis == b_has_basis) {

						if (!a_has_basis) {
							// Finally, equality
							return false;
						}
						else {
							return less(a.basis, b.basis);
						}

					}
					else {
						return a_has_basis < b_has_basis;
					}

				}
				else {
					return end_state == -1;
				}

			}
			else {
				return start_state == -1;
			}

		}
		else {
			return
				std::tie(a.orientation, a_which_start, a_which_end) <
				std::tie(b.orientation, b_which_start, b_which_end);
		}
	}

	template <typename T>
	bool compare_collection(const collection_base<T>& a, const collection_base<T>& b) {
		if (a.children.size() == b.children.size()) {
			auto at = a.children.begin();
			auto bt = b.children.begin();
			for (; at != a.children.end(); ++at, ++bt) {
				const bool a_lt_b = less(*at, *bt);
				const bool b_lt_a = less(*bt, *at);
				if (!a_lt_b && !b_lt_a) {
					// Elements equal.
					continue;
				}
				return a_lt_b;
			}
			// Vectors equal, compare matrix (in case of mapped items).
			return compare(*a.matrix, *b.matrix);
		}
		else {
			return a.children.size() < b.children.size();
		}
	}

	bool compare(const loop& a, const loop& b) {
		return compare_collection<edge>(a, b);
	}

	bool compare(const face& a, const face& b) {
		return compare_collection<loop>(a, b);
	}

	bool compare(const shell& a, const shell& b) {
		return compare_collection<face>(a, b);
	}

	bool compare(const solid& a, const solid& b) {
		return compare_collection<shell>(a, b);
	}

	bool compare(const loft& a, const loft& b) {
		return compare_collection<face>(a, b);
	}

	bool compare(const collection& a, const collection& b) {
		return compare_collection<geom_item>(a, b);
	}

	bool compare(const boolean_result& a, const boolean_result& b) {
		return compare_collection<geom_item>(a, b);
	}
}

ifcopenshell::geometry::taxonomy::solid::ptr ifcopenshell::geometry::create_box(double dx, double dy, double dz) {
	return create_box(0., 0., 0., dx, dy, dz);
}

ifcopenshell::geometry::taxonomy::solid::ptr ifcopenshell::geometry::create_box(double x, double y, double z, double dx, double dy, double dz) {
	auto solid = make<taxonomy::solid>();
	auto shell = make<taxonomy::shell>();
	solid->children.push_back(shell);

	// x = 0
	{
		auto face = make<taxonomy::face>();
		auto loop = make<taxonomy::loop>();
		face->children.push_back(loop);
		loop->external = true;
		shell->children.push_back(face);

		std::array<taxonomy::point3::ptr, 4> points{
			taxonomy::make<taxonomy::point3>(x + 0, y + 0,  z + 0),
			taxonomy::make<taxonomy::point3>(x + 0, y + dy, z + 0),
			taxonomy::make<taxonomy::point3>(x + 0, y + dy, z + dz),
			taxonomy::make<taxonomy::point3>(x + 0, y + 0,  z + dz)
		};

		loop->children.push_back(make<taxonomy::edge>(points[0], points[1]));
		loop->children.push_back(make<taxonomy::edge>(points[1], points[2]));
		loop->children.push_back(make<taxonomy::edge>(points[2], points[3]));
		loop->children.push_back(make<taxonomy::edge>(points[3], points[0]));
	}

	// x = dx
	{
		auto face = make<taxonomy::face>();
		auto loop = make<taxonomy::loop>();
		face->children.push_back(loop);
		loop->external = true;
		shell->children.push_back(face);

		std::array<taxonomy::point3::ptr, 4> points{
			taxonomy::make<taxonomy::point3>(x + dx, y + 0,  z + 0),
			taxonomy::make<taxonomy::point3>(x + dx, y + 0,  z + dz),
			taxonomy::make<taxonomy::point3>(x + dx, y + dy, z + dz),
			taxonomy::make<taxonomy::point3>(x + dx, y + dy, z + 0)
		};

		loop->children.push_back(make<taxonomy::edge>(points[0], points[1]));
		loop->children.push_back(make<taxonomy::edge>(points[1], points[2]));
		loop->children.push_back(make<taxonomy::edge>(points[2], points[3]));
		loop->children.push_back(make<taxonomy::edge>(points[3], points[0]));
	}

	// y = 0
	{
		auto face = make<taxonomy::face>();
		auto loop = make<taxonomy::loop>();
		face->children.push_back(loop);
		loop->external = true;
		shell->children.push_back(face);

		std::array<taxonomy::point3::ptr, 4> points{
			taxonomy::make<taxonomy::point3>(x + 0,  y + 0, z + 0),
			taxonomy::make<taxonomy::point3>(x + 0,  y + 0, z + dz),
			taxonomy::make<taxonomy::point3>(x + dx, y + 0, z + dz),
			taxonomy::make<taxonomy::point3>(x + dx, y + 0, z + 0)
		};

		loop->children.push_back(make<taxonomy::edge>(points[0], points[1]));
		loop->children.push_back(make<taxonomy::edge>(points[1], points[2]));
		loop->children.push_back(make<taxonomy::edge>(points[2], points[3]));
		loop->children.push_back(make<taxonomy::edge>(points[3], points[0]));
	}

	// y = dy
	{
		auto face = make<taxonomy::face>();
		auto loop = make<taxonomy::loop>();
		face->children.push_back(loop);
		loop->external = true;
		shell->children.push_back(face);

		std::array<taxonomy::point3::ptr, 4> points{
			taxonomy::make<taxonomy::point3>(x + 0, y + dy, z + 0),
			taxonomy::make<taxonomy::point3>(x + dx, y + dy, z + 0),
			taxonomy::make<taxonomy::point3>(x + dx, y + dy, z + dz),
			taxonomy::make<taxonomy::point3>(x + 0, y + dy, z + dz)
		};

		loop->children.push_back(make<taxonomy::edge>(points[0], points[1]));
		loop->children.push_back(make<taxonomy::edge>(points[1], points[2]));
		loop->children.push_back(make<taxonomy::edge>(points[2], points[3]));
		loop->children.push_back(make<taxonomy::edge>(points[3], points[0]));
	}

	// z = 0
	{
		auto face = make<taxonomy::face>();
		auto loop = make<taxonomy::loop>();
		face->children.push_back(loop);
		loop->external = true;
		shell->children.push_back(face);

		std::array<taxonomy::point3::ptr, 4> points{
			taxonomy::make<taxonomy::point3>(x + 0, y + 0, z + 0),
			taxonomy::make<taxonomy::point3>(x + dx, y + 0, z + 0),
			taxonomy::make<taxonomy::point3>(x + dx, y + dy, z + 0),
			taxonomy::make<taxonomy::point3>(x + 0, y + dy, z + 0)
		};

		loop->children.push_back(make<taxonomy::edge>(points[0], points[1]));
		loop->children.push_back(make<taxonomy::edge>(points[1], points[2]));
		loop->children.push_back(make<taxonomy::edge>(points[2], points[3]));
		loop->children.push_back(make<taxonomy::edge>(points[3], points[0]));
	}

	// z = dz
	{
		auto face = make<taxonomy::face>();
		auto loop = make<taxonomy::loop>();
		face->children.push_back(loop);
		loop->external = true;
		shell->children.push_back(face);

		std::array<taxonomy::point3::ptr, 4> points{
			taxonomy::make<taxonomy::point3>(x + 0, y + 0, z + dz),
			taxonomy::make<taxonomy::point3>(x + 0, y + dy, z + dz),
			taxonomy::make<taxonomy::point3>(x + dx, y + dy, z + dz),
			taxonomy::make<taxonomy::point3>(x + dx, y + 0, z + dz)
		};

		loop->children.push_back(make<taxonomy::edge>(points[0], points[1]));
		loop->children.push_back(make<taxonomy::edge>(points[1], points[2]));
		loop->children.push_back(make<taxonomy::edge>(points[2], points[3]));
		loop->children.push_back(make<taxonomy::edge>(points[3], points[0]));
	}

	return solid;
}

ifcopenshell::geometry::taxonomy::item::ptr ifcopenshell::geometry::taxonomy::piecewise_function::evaluate() const {
    return evaluate2().first;
}

std::pair<item::ptr, std::vector<double>> ifcopenshell::geometry::taxonomy::piecewise_function::evaluate2() const {
    double curve_length = length();

    std::vector<taxonomy::point3::ptr> polygon;

    auto param_type = settings_ ? settings_->get<ifcopenshell::geometry::settings::PiecewiseStepType>().get() : ifcopenshell::geometry::settings::PiecewiseStepMethod::MAXSTEPSIZE;
    auto param = settings_ ? settings_->get<ifcopenshell::geometry::settings::PiecewiseStepParam>().get() : 0.5;
    unsigned num_steps = 0;
    if (param_type == ifcopenshell::geometry::settings::PiecewiseStepMethod::MAXSTEPSIZE) {
        // parameter is max step size
        num_steps = (unsigned)std::ceil(curve_length / param);
    } else {
        // parameter is minimum number of steps
        num_steps = (unsigned)std::ceil(param);
    }

    num_steps = std::max(1u, num_steps); // never have fewer than 1 step

    return evaluate2(0.0, curve_length, num_steps);
}

item::ptr ifcopenshell::geometry::taxonomy::piecewise_function::evaluate(double ustart, double uend,unsigned nsteps) const {
    return evaluate2(ustart, uend, nsteps).first;
}

std::pair<item::ptr, std::vector<double>> ifcopenshell::geometry::taxonomy::piecewise_function::evaluate2(double ustart, double uend, unsigned nsteps) const {
    double curve_length = length();
    ustart = std::max(0.0, ustart);
    uend = std::min(uend, curve_length);

    auto resolution = (uend - ustart) / nsteps;

    std::vector<taxonomy::point3::ptr> polygon;
    std::vector<double> u_values;
    polygon.reserve(nsteps);
    u_values.reserve(nsteps);

    for (unsigned i = 0; i <= nsteps; ++i) {
        auto u = resolution * i + ustart;
        u_values.push_back(u);
        Eigen::Matrix4d m = evaluate(u);
        polygon.push_back(taxonomy::make<taxonomy::point3>(m.col(3)(0), m.col(3)(1), m.col(3)(2)));
    }

    return {polygon_from_points(polygon), u_values};
}

Eigen::Matrix4d ifcopenshell::geometry::taxonomy::piecewise_function::evaluate(double u) const {
	// assume monotonic evaluation and store last evaluated segment
    if (current_span_fn_ == nullptr || (u < current_span_start_ || current_span_end_ < u)) {
       // there isn't a current span or u is outside the range of the current span
		 // get a new "current span"
        std::tie(current_span_start_,current_span_end_, current_span_fn_) = get_span(u);
    }

	 u -= current_span_start_; // make u relative to start of span
	 return (*current_span_fn_)(u);
}

std::tuple<double, double, const std::function<Eigen::Matrix4d(double u)>*> ifcopenshell::geometry::taxonomy::piecewise_function::get_span(double u) const {
	 // force u to be within bounds of the curve
    double curve_length = length();
    u = std::max(0.0, u);
    u = std::min(u, curve_length);

	double start = 0;
    for (auto& [length, fn] : spans_) {
		 auto tolerance = settings_ ? settings_->get<ifcopenshell::geometry::settings::Precision>().get() : 0.001;
       if (u < length + tolerance) {
           return {start, start+length, &fn} ;
       }
       start += length;
       u -= length;
    }

    Logger::Error("taxonomy::piecewise_function::get_span span not found.");
    return {0, 0, nullptr};
}

ifcopenshell::geometry::taxonomy::collection::ptr ifcopenshell::geometry::flatten(const taxonomy::collection::ptr& deep) {
	auto flat = make<taxonomy::collection>();
	ifcopenshell::geometry::visit<taxonomy::collection>(deep, [&flat](taxonomy::ptr i) {
		flat->children.push_back(taxonomy::cast<taxonomy::geom_item>(clone(i)));
		});
	return flat;
}

const std::string& ifcopenshell::geometry::taxonomy::kind_to_string(kinds k) {
	using namespace std::string_literals;

	static std::string values[] = {
		"matrix4"s, "point3"s, "direction3"s, "line"s, "circle"s, "ellipse"s, "bspline_curve"s, "offset_curve"s, "plane"s, "cylinder"s, "sphere"s, "torus"s, "bspline_surface"s, "edge"s, "loop"s, "face"s, "shell"s, "solid"s, "loft"s, "extrusion"s, "revolve"s, "sweep_along_curve"s, "node"s, "collection"s, "boolean_result"s, "piecewise_function"s, "colour"s, "style"s,
	};

	return values[k];
}

std::atomic_uint32_t item::counter_(0);

void ifcopenshell::geometry::taxonomy::item::print(std::ostream& o, int indent) const {
	o << std::string(indent, ' ') << kind_to_string(kind()) << std::endl;
}

void ifcopenshell::geometry::taxonomy::matrix4::print(std::ostream& o, int indent) const {
	print_impl(o, kind_to_string(kind()), indent);
}

void ifcopenshell::geometry::taxonomy::colour::print(std::ostream& o, int indent) const {
	print_impl(o, kind_to_string(kind()), indent);
}

void ifcopenshell::geometry::taxonomy::style::print(std::ostream& o, int indent) const {
	o << std::string(indent, ' ') << "style" << std::endl;
	o << std::string(indent, ' ') << "     " << "name " << (name) << std::endl;
	if (diffuse.components_) {
		o << std::string(indent, ' ') << "     " << "diffuse" << std::endl;
		diffuse.print(o, indent + 5 + 7);
	}
	if (specular.components_) {
		o << std::string(indent, ' ') << "     " << "specular" << std::endl;
		specular.print(o, indent + 5 + 8);
	}
	// @todo
}

void ifcopenshell::geometry::taxonomy::point3::print(std::ostream& o, int indent) const {
	print_impl(o, kind_to_string(kind()), indent);
}

void ifcopenshell::geometry::taxonomy::direction3::print(std::ostream& o, int indent) const {
	print_impl(o, kind_to_string(kind()), indent);
}

void ifcopenshell::geometry::taxonomy::line::print(std::ostream& o, int indent) const {
	print_impl(o, kind_to_string(kind()), indent);
}

void ifcopenshell::geometry::taxonomy::circle::print(std::ostream& o, int indent) const {
	print_impl(o, kind_to_string(kind()), indent);
	o << std::string(indent + 4, ' ') << "radius " << radius << std::endl;
}

void ifcopenshell::geometry::taxonomy::ellipse::print(std::ostream& o, int indent) const {
	print_impl(o, kind_to_string(kind()), indent);
	o << std::string(indent + 4, ' ') << "radii " << radius << " " << radius2 << std::endl;
}

void ifcopenshell::geometry::taxonomy::trimmed_curve::print(std::ostream& o, int indent) const {
	o << std::string(indent, ' ') << kind_to_string(kind());
	if (!this->orientation.get_value_or(true)) {
		o << " [R]";
	} else {
		o << " [ ]";
	}
	if (!this->curve_sense.get_value_or(true)) {
		o << " [R]";
	} else {
		o << " [ ]";
	}
	o << std::endl;
	if (basis) {
		basis->print(o, indent + 4);
	}

	const boost::variant<boost::blank, point3::ptr, double>* const start_end[2] = { &start, &end };
	for (int i = 0; i < 2; ++i) {
		o << std::string(indent + 4, ' ') << (i == 0 ? "start" : "end") << std::endl;
		if (start_end[i]->which() == 1) {
			boost::get<point3::ptr>(*start_end[i])->print(o, indent + 4);
		} else if (start_end[i]->which() == 2) {
			o << std::string(indent + 4, ' ') << "parameter " << boost::get<double>(*start_end[i]) << std::endl;
		}
	}

	if (this->instance) {
		o << std::string(indent + 4, ' ') << this->instance->data().toString() << std::endl;
	}
}

void ifcopenshell::geometry::taxonomy::extrusion::print(std::ostream& o, int indent) const {
	o << std::string(indent, ' ') << "extrusion " << depth << std::endl;
	direction->print(o, indent + 4);
	basis->print(o, indent + 4);
}