#include <mbgl/style/conversion/property_value.hpp>
#include <mbgl/style/conversion/position.hpp>
#include <mbgl/style/conversion_impl.hpp>

namespace mbgl {
namespace style {
namespace conversion {

template <class T>
optional<PropertyValue<T>> Converter<PropertyValue<T>>::operator()(const Convertible& value, Error& error, bool allowDataExpressions, bool convertTokens) const {
    using namespace mbgl::style::expression;

    if (isUndefined(value)) {
        return PropertyValue<T>();
    }

    optional<PropertyExpression<T>> expression;

    if (isExpression(value)) {
        ParsingContext ctx(valueTypeToExpressionType<T>());
        ParseResult parsed = ctx.parseLayerPropertyExpression(value);
        if (!parsed) {
            error.message = ctx.getCombinedErrors();
            return nullopt;
        }
        expression = PropertyExpression<T>(std::move(*parsed));
    } else if (isObject(value)) {
        expression = convertFunctionToExpression<T>(value, error, convertTokens);
    } else {
        optional<T> constant = convert<T>(value, error);
        if (!constant) {
            return nullopt;
        }
        return convertTokens ? maybeConvertTokens(*constant) : PropertyValue<T>(*constant);
    }

    if (!expression) {
        return nullopt;
    } else if (!allowDataExpressions && !(*expression).isFeatureConstant()) {
        error.message = "data expressions not supported";
        return nullopt;
    } else if (!(*expression).isFeatureConstant() || !(*expression).isZoomConstant()) {
        return { std::move(*expression) };
    } else if ((*expression).getExpression().getKind() == Kind::Literal) {
        optional<T> constant = fromExpressionValue<T>(
            static_cast<const Literal&>((*expression).getExpression()).getValue());
        if (!constant) {
            return nullopt;
        }
        return PropertyValue<T>(*constant);
    } else {
        assert(false);
        error.message = "expected a literal expression";
        return nullopt;
    }
}

template optional<PropertyValue<bool>> Converter<PropertyValue<bool>>::operator()(conversion::Convertible const&, conversion::Error&, bool, bool) const;
template optional<PropertyValue<float>> Converter<PropertyValue<float>>::operator()(conversion::Convertible const&, conversion::Error&, bool, bool) const;
template optional<PropertyValue<std::array<float, 2>>> Converter<PropertyValue<std::array<float, 2>>>::operator()(conversion::Convertible const&, conversion::Error&, bool, bool) const;
template optional<PropertyValue<std::array<float, 4>>> Converter<PropertyValue<std::array<float, 4>>>::operator()(conversion::Convertible const&, conversion::Error&, bool, bool) const;
template optional<PropertyValue<std::vector<float>>> Converter<PropertyValue<std::vector<float>>>::operator()(conversion::Convertible const&, conversion::Error&, bool, bool) const;
template optional<PropertyValue<Color>> Converter<PropertyValue<Color>>::operator()(conversion::Convertible const&, conversion::Error&, bool, bool) const;
template optional<PropertyValue<std::string>> Converter<PropertyValue<std::string>>::operator()(conversion::Convertible const&, conversion::Error&, bool, bool) const;
template optional<PropertyValue<std::vector<std::string>>> Converter<PropertyValue<std::vector<std::string>>>::operator()(conversion::Convertible const&, conversion::Error&, bool, bool) const;
template optional<PropertyValue<AlignmentType>> Converter<PropertyValue<AlignmentType>>::operator()(conversion::Convertible const&, conversion::Error&, bool, bool) const;
template optional<PropertyValue<CirclePitchScaleType>> Converter<PropertyValue<CirclePitchScaleType>>::operator()(conversion::Convertible const&, conversion::Error&, bool, bool) const;
template optional<PropertyValue<HillshadeIlluminationAnchorType>> Converter<PropertyValue<HillshadeIlluminationAnchorType>>::operator()(conversion::Convertible const&, conversion::Error&, bool, bool) const;
template optional<PropertyValue<IconTextFitType>> Converter<PropertyValue<IconTextFitType>>::operator()(conversion::Convertible const&, conversion::Error&, bool, bool) const;
template optional<PropertyValue<LightAnchorType>> Converter<PropertyValue<LightAnchorType>>::operator()(conversion::Convertible const&, conversion::Error&, bool, bool) const;
template optional<PropertyValue<LineCapType>> Converter<PropertyValue<LineCapType>>::operator()(conversion::Convertible const&, conversion::Error&, bool, bool) const;
template optional<PropertyValue<LineJoinType>> Converter<PropertyValue<LineJoinType>>::operator()(conversion::Convertible const&, conversion::Error&, bool, bool) const;
template optional<PropertyValue<Position>> Converter<PropertyValue<Position>>::operator()(conversion::Convertible const&, conversion::Error&, bool, bool) const;
template optional<PropertyValue<RasterResamplingType>> Converter<PropertyValue<RasterResamplingType>>::operator()(conversion::Convertible const&, conversion::Error&, bool, bool) const;
template optional<PropertyValue<SymbolAnchorType>> Converter<PropertyValue<SymbolAnchorType>>::operator()(conversion::Convertible const&, conversion::Error&, bool, bool) const;
template optional<PropertyValue<std::vector<TextVariableAnchorType>>> Converter<PropertyValue<std::vector<TextVariableAnchorType>>>::operator()(conversion::Convertible const&, conversion::Error&, bool, bool) const;
template optional<PropertyValue<SymbolPlacementType>> Converter<PropertyValue<SymbolPlacementType>>::operator()(conversion::Convertible const&, conversion::Error&, bool, bool) const;
template optional<PropertyValue<SymbolZOrderType>> Converter<PropertyValue<SymbolZOrderType>>::operator()(conversion::Convertible const&, conversion::Error&, bool, bool) const;
template optional<PropertyValue<TextJustifyType>> Converter<PropertyValue<TextJustifyType>>::operator()(conversion::Convertible const&, conversion::Error&, bool, bool) const;
template optional<PropertyValue<TextTransformType>> Converter<PropertyValue<TextTransformType>>::operator()(conversion::Convertible const&, conversion::Error&, bool, bool) const;
template optional<PropertyValue<TranslateAnchorType>> Converter<PropertyValue<TranslateAnchorType>>::operator()(conversion::Convertible const&, conversion::Error&, bool, bool) const;
template optional<PropertyValue<mbgl::style::expression::Formatted>> Converter<PropertyValue<mbgl::style::expression::Formatted>>::operator()(conversion::Convertible const&, conversion::Error&, bool, bool) const;

} // namespace conversion
} // namespace style
} // namespace mbgl