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#include <mbgl/style/expression/assertion.hpp>
#include <mbgl/style/expression/check_subtype.hpp>
#include <mbgl/style/conversion_impl.hpp>
namespace mbgl {
namespace style {
namespace expression {
using namespace mbgl::style::conversion;
Assertion::Assertion(type::Type type_, std::vector<std::unique_ptr<Expression>> inputs_) :
Expression(Kind::Assertion, type_),
inputs(std::move(inputs_))
{
assert(!inputs.empty());
}
ParseResult Assertion::parse(const Convertible& value, ParsingContext& ctx) {
static std::unordered_map<std::string, type::Type> types{
{"string", type::String},
{"image", type::String}, // TODO: replace once we implement image expressions
{"number", type::Number},
{"boolean", type::Boolean},
{"object", type::Object}};
std::size_t length = arrayLength(value);
if (length < 2) {
ctx.error("Expected at least one argument.");
return ParseResult();
}
std::size_t i = 1;
type::Type type;
std::string name = *toString(arrayMember(value, 0));
if (name == "array") {
optional<type::Type> itemType;
if (length > 2) {
optional<std::string> itemTypeName = toString(arrayMember(value, 1));
auto it = itemTypeName ? types.find(*itemTypeName) : types.end();
if (it == types.end() || it->second == type::Object) {
ctx.error(
R"(The item type argument of "array" must be one of string, number, boolean)",
1
);
return ParseResult();
}
itemType = it->second;
i++;
} else {
itemType = {type::Value};
}
optional<std::size_t> N;
if (length > 3) {
auto m = arrayMember(value, 2);
optional<float> n = toNumber(m);
if (!isUndefined(m) &&
(!n || *n < 0 || *n != std::floor(*n))) {
ctx.error(
R"(The length argument to "array" must be a positive integer literal.)",
2
);
return ParseResult();
}
if (n) {
N = optional<std::size_t>(*n);
}
i++;
}
type = type::Array(*itemType, N);
} else {
type = types.at(name);
}
std::vector<std::unique_ptr<Expression>> parsed;
parsed.reserve(length - 1);
for (; i < length; i++) {
ParseResult input = ctx.parse(arrayMember(value, i), i, {type::Value});
if (!input) return ParseResult();
parsed.push_back(std::move(*input));
}
return ParseResult(std::make_unique<Assertion>(type, std::move(parsed)));
}
std::string Assertion::getOperator() const {
return getType().is<type::Array>() ? "array" : type::toString(getType());
}
EvaluationResult Assertion::evaluate(const EvaluationContext& params) const {
for (std::size_t i = 0; i < inputs.size(); i++) {
EvaluationResult value = inputs[i]->evaluate(params);
if (!value) return value;
if (!type::checkSubtype(getType(), typeOf(*value))) {
return value;
} else if (i == inputs.size() - 1) {
return EvaluationError {
"Expected value to be of type " + toString(getType()) +
", but found " + toString(typeOf(*value)) + " instead."
};
}
}
assert(false);
return EvaluationError { "Unreachable" };
};
void Assertion::eachChild(const std::function<void(const Expression&)>& visit) const {
for(const std::unique_ptr<Expression>& input : inputs) {
visit(*input);
}
};
bool Assertion::operator==(const Expression& e) const {
if (e.getKind() == Kind::Assertion) {
auto rhs = static_cast<const Assertion*>(&e);
return getType() == rhs->getType() && Expression::childrenEqual(inputs, rhs->inputs);
}
return false;
}
std::vector<optional<Value>> Assertion::possibleOutputs() const {
std::vector<optional<Value>> result;
for (const auto& input : inputs) {
for (auto& output : input->possibleOutputs()) {
result.push_back(std::move(output));
}
}
return result;
}
mbgl::Value Assertion::serialize() const {
std::vector<mbgl::Value> serialized;
serialized.emplace_back(getOperator());
if (getType().is<type::Array>()) {
const auto array = getType().get<type::Array>();
if (array.itemType.is<type::StringType>()
|| array.itemType.is<type::NumberType>()
|| array.itemType.is<type::BooleanType>()) {
serialized.emplace_back(type::toString(array.itemType));
if (array.N) {
serialized.emplace_back(uint64_t(*array.N));
} else if (inputs.size() > 1) {
serialized.emplace_back(mbgl::NullValue());
}
}
}
for (const auto& input : inputs) {
serialized.emplace_back(input->serialize());
}
return serialized;
}
} // namespace expression
} // namespace style
} // namespace mbgl
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