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#include "node_conversion.hpp"
#include "node_expression.hpp"
#include "node_feature.hpp"
#include <mbgl/style/expression/parsing_context.hpp>
#include <mbgl/style/expression/is_constant.hpp>
#include <mbgl/style/conversion/geojson.hpp>
#include <mbgl/util/geojson.hpp>
#include <nan.h>
using namespace mbgl::style;
using namespace mbgl::style::expression;
namespace node_mbgl {
Nan::Persistent<v8::Function> NodeExpression::constructor;
void NodeExpression::Init(v8::Local<v8::Object> target) {
v8::Local<v8::FunctionTemplate> tpl = Nan::New<v8::FunctionTemplate>(New);
tpl->SetClassName(Nan::New("Expression").ToLocalChecked());
tpl->InstanceTemplate()->SetInternalFieldCount(1); // what is this doing?
Nan::SetPrototypeMethod(tpl, "evaluate", Evaluate);
Nan::SetPrototypeMethod(tpl, "getType", GetType);
Nan::SetPrototypeMethod(tpl, "isFeatureConstant", IsFeatureConstant);
Nan::SetPrototypeMethod(tpl, "isZoomConstant", IsZoomConstant);
Nan::SetPrototypeMethod(tpl, "serialize", Serialize);
Nan::SetMethod(tpl, "parse", Parse);
constructor.Reset(tpl->GetFunction()); // what is this doing?
Nan::Set(target, Nan::New("Expression").ToLocalChecked(), tpl->GetFunction());
}
type::Type parseType(v8::Local<v8::Object> type) {
static std::unordered_map<std::string, type::Type> types = {
{"string", type::String},
{"number", type::Number},
{"noolean", type::Boolean},
{"object", type::Object},
{"color", type::Color},
{"value", type::Value}
};
v8::Local<v8::Value> v8kind = Nan::Get(type, Nan::New("kind").ToLocalChecked()).ToLocalChecked();
std::string kind(*v8::String::Utf8Value(v8kind));
if (kind == "array") {
type::Type itemType = parseType(Nan::Get(type, Nan::New("itemType").ToLocalChecked()).ToLocalChecked()->ToObject());
mbgl::optional<std::size_t> N;
v8::Local<v8::String> Nkey = Nan::New("N").ToLocalChecked();
if (Nan::Has(type, Nkey).FromMaybe(false)) {
N = Nan::Get(type, Nkey).ToLocalChecked()->ToInt32()->Value();
}
return type::Array(itemType, N);
}
return types[kind];
}
void NodeExpression::Parse(const Nan::FunctionCallbackInfo<v8::Value>& info) {
v8::Local<v8::Function> cons = Nan::New(constructor);
if (info.Length() < 1 || info[0]->IsUndefined()) {
return Nan::ThrowTypeError("Requires a JSON style expression argument.");
}
mbgl::optional<type::Type> expected;
if (info.Length() > 1 && info[1]->IsObject()) {
expected = parseType(info[1]->ToObject());
}
auto expr = info[0];
try {
ParsingContext ctx(expected);
ParseResult parsed = ctx.parse(mbgl::style::conversion::Convertible(expr));
if (parsed) {
assert(ctx.getErrors().size() == 0);
auto nodeExpr = new NodeExpression(std::move(*parsed));
const int argc = 0;
v8::Local<v8::Value> argv[0] = {};
auto wrapped = Nan::NewInstance(cons, argc, argv).ToLocalChecked();
nodeExpr->Wrap(wrapped);
info.GetReturnValue().Set(wrapped);
return;
}
v8::Local<v8::Array> result = Nan::New<v8::Array>();
for (std::size_t i = 0; i < ctx.getErrors().size(); i++) {
const auto& error = ctx.getErrors()[i];
v8::Local<v8::Object> err = Nan::New<v8::Object>();
Nan::Set(err,
Nan::New("key").ToLocalChecked(),
Nan::New(error.key.c_str()).ToLocalChecked());
Nan::Set(err,
Nan::New("error").ToLocalChecked(),
Nan::New(error.message.c_str()).ToLocalChecked());
Nan::Set(result, Nan::New((uint32_t)i), err);
}
info.GetReturnValue().Set(result);
} catch(std::exception &ex) {
return Nan::ThrowError(ex.what());
}
}
void NodeExpression::New(const Nan::FunctionCallbackInfo<v8::Value>& info) {
if (!info.IsConstructCall()) {
return Nan::ThrowTypeError("Use the new operator to create new Expression objects");
}
info.GetReturnValue().Set(info.This());
}
struct ToValue {
v8::Local<v8::Value> operator()(mbgl::NullValue) {
Nan::EscapableHandleScope scope;
return scope.Escape(Nan::Null());
}
v8::Local<v8::Value> operator()(bool t) {
Nan::EscapableHandleScope scope;
return scope.Escape(Nan::New(t));
}
v8::Local<v8::Value> operator()(double t) {
Nan::EscapableHandleScope scope;
return scope.Escape(Nan::New(t));
}
v8::Local<v8::Value> operator()(const std::string& t) {
Nan::EscapableHandleScope scope;
return scope.Escape(Nan::New(t).ToLocalChecked());
}
v8::Local<v8::Value> operator()(const std::vector<Value>& array) {
Nan::EscapableHandleScope scope;
v8::Local<v8::Array> result = Nan::New<v8::Array>();
for (unsigned int i = 0; i < array.size(); i++) {
result->Set(i, toJS(array[i]));
}
return scope.Escape(result);
}
v8::Local<v8::Value> operator()(const mbgl::Color& color) {
return operator()(std::vector<Value> {
static_cast<double>(color.r),
static_cast<double>(color.g),
static_cast<double>(color.b),
static_cast<double>(color.a)
});
}
v8::Local<v8::Value> operator()(const std::unordered_map<std::string, Value>& map) {
Nan::EscapableHandleScope scope;
v8::Local<v8::Object> result = Nan::New<v8::Object>();
for (const auto& entry : map) {
Nan::Set(result, Nan::New(entry.first).ToLocalChecked(), toJS(entry.second));
}
return scope.Escape(result);
}
};
v8::Local<v8::Value> toJS(const Value& value) {
return Value::visit(value, ToValue());
}
void NodeExpression::Evaluate(const Nan::FunctionCallbackInfo<v8::Value>& info) {
NodeExpression* nodeExpr = ObjectWrap::Unwrap<NodeExpression>(info.Holder());
const std::unique_ptr<Expression>& expression = nodeExpr->expression;
if (info.Length() < 2 || !info[0]->IsObject()) {
return Nan::ThrowTypeError("Requires globals and feature arguments.");
}
mbgl::optional<float> zoom;
v8::Local<v8::Value> v8zoom = Nan::Get(info[0]->ToObject(), Nan::New("zoom").ToLocalChecked()).ToLocalChecked();
if (v8zoom->IsNumber()) zoom = v8zoom->NumberValue();
mbgl::optional<double> heatmapDensity;
v8::Local<v8::Value> v8heatmapDensity = Nan::Get(info[0]->ToObject(), Nan::New("heatmapDensity").ToLocalChecked()).ToLocalChecked();
if (v8heatmapDensity->IsNumber()) heatmapDensity = v8heatmapDensity->NumberValue();
Nan::JSON NanJSON;
conversion::Error conversionError;
mbgl::optional<mbgl::GeoJSON> geoJSON = conversion::convert<mbgl::GeoJSON>(info[1], conversionError);
if (!geoJSON) {
Nan::ThrowTypeError(conversionError.message.c_str());
return;
}
try {
mapbox::geojson::feature feature = geoJSON->get<mapbox::geojson::feature>();
auto result = expression->evaluate(zoom, feature, heatmapDensity);
if (result) {
info.GetReturnValue().Set(toJS(*result));
} else {
v8::Local<v8::Object> res = Nan::New<v8::Object>();
Nan::Set(res,
Nan::New("error").ToLocalChecked(),
Nan::New(result.error().message.c_str()).ToLocalChecked());
info.GetReturnValue().Set(res);
}
} catch(std::exception &ex) {
return Nan::ThrowTypeError(ex.what());
}
}
void NodeExpression::GetType(const Nan::FunctionCallbackInfo<v8::Value>& info) {
NodeExpression* nodeExpr = ObjectWrap::Unwrap<NodeExpression>(info.Holder());
const std::unique_ptr<Expression>& expression = nodeExpr->expression;
const type::Type type = expression->getType();
const std::string name = type.match([&] (const auto& t) { return t.getName(); });
info.GetReturnValue().Set(Nan::New(name.c_str()).ToLocalChecked());
}
void NodeExpression::IsFeatureConstant(const Nan::FunctionCallbackInfo<v8::Value>& info) {
NodeExpression* nodeExpr = ObjectWrap::Unwrap<NodeExpression>(info.Holder());
const std::unique_ptr<Expression>& expression = nodeExpr->expression;
info.GetReturnValue().Set(Nan::New(isFeatureConstant(*expression)));
}
void NodeExpression::IsZoomConstant(const Nan::FunctionCallbackInfo<v8::Value>& info) {
NodeExpression* nodeExpr = ObjectWrap::Unwrap<NodeExpression>(info.Holder());
const std::unique_ptr<Expression>& expression = nodeExpr->expression;
info.GetReturnValue().Set(Nan::New(isZoomConstant(*expression)));
}
void NodeExpression::Serialize(const Nan::FunctionCallbackInfo<v8::Value>& info) {
NodeExpression* nodeExpr = ObjectWrap::Unwrap<NodeExpression>(info.Holder());
const std::unique_ptr<Expression>& expression = nodeExpr->expression;
const mbgl::Value serialized = expression->serialize();
info.GetReturnValue().Set(toJS(serialized));
}
} // namespace node_mbgl
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