[Qt] Check if property value is a valid JSON string

4 files changed, 71 insertions, 33 deletions

diff --git a/platform/qt/app/mapwindow.cpp b/platform/qt/app/mapwindow.cpp
index 390d89915a..536731929e 100644
--- a/platform/qt/app/mapwindow.cpp
+++ b/platform/qt/app/mapwindow.cpp
@@ -229,7 +229,21 @@ void MapWindow::keyPressEvent(QKeyEvent *ev)
 
             m_map->setFilter("3d-buildings", buildingsFilterExpression);
 
-            m_map->setPaintProperty("3d-buildings", "fill-extrusion-color", "#aaa");
+            QString fillExtrusionColorJSON = R"JSON(
+              [
+                "interpolate",
+                ["linear"],
+                ["get", "height"],
+                  0.0, "blue",
+                 20.0, "royalblue",
+                 40.0, "cyan",
+                 60.0, "lime",
+                 80.0, "yellow",
+                100.0, "red"
+              ]
+            )JSON";
+
+            m_map->setPaintProperty("3d-buildings", "fill-extrusion-color", fillExtrusionColorJSON);
             m_map->setPaintProperty("3d-buildings", "fill-extrusion-opacity", .6);
 
             QVariantMap extrusionHeight;
diff --git a/platform/qt/qt.cmake b/platform/qt/qt.cmake
index fafbb895dc..ce43177daa 100644
--- a/platform/qt/qt.cmake
+++ b/platform/qt/qt.cmake
@@ -79,6 +79,7 @@ add_library(qmapboxgl SHARED
 
 target_include_directories(qmapboxgl
     PUBLIC platform/qt/include
+    PRIVATE src
 )
 
 target_compile_definitions(qmapboxgl
diff --git a/platform/qt/src/qmapboxgl.cpp b/platform/qt/src/qmapboxgl.cpp
index 05cb5b7f93..459eacba4b 100644
--- a/platform/qt/src/qmapboxgl.cpp
+++ b/platform/qt/src/qmapboxgl.cpp
@@ -27,6 +27,7 @@
 #include <mbgl/style/layers/line_layer.hpp>
 #include <mbgl/style/layers/raster_layer.hpp>
 #include <mbgl/style/layers/symbol_layer.hpp>
+#include <mbgl/style/rapidjson_conversion.hpp>
 #include <mbgl/style/sources/geojson_source.hpp>
 #include <mbgl/style/transition_options.hpp>
 #include <mbgl/style/image.hpp>
@@ -38,6 +39,7 @@
 #include <mbgl/util/geo.hpp>
 #include <mbgl/util/geometry.hpp>
 #include <mbgl/util/projection.hpp>
+#include <mbgl/util/rapidjson.hpp>
 #include <mbgl/util/run_loop.hpp>
 #include <mbgl/util/shared_thread_pool.hpp>
 #include <mbgl/util/traits.hpp>
@@ -60,7 +62,9 @@
 #include <QVariantMap>
 #include <QColor>
 
+#include <functional>
 #include <memory>
+#include <sstream>
 
 using namespace QMapbox;
 
@@ -977,6 +981,10 @@ void QMapboxGL::removeAnnotation(QMapbox::AnnotationID id)
     as defined by the \l {https://www.mapbox.com/mapbox-gl-style-spec/} {Mapbox style specification}
     for layout properties. Returns true if the operation succeeds, and false otherwise.
 
+    The implementation attempts to treat \a value as a JSON string, if the
+    QVariant inner type is a string. If not a valid JSON string, then it'll
+    proceed with the mapping described below.
+
     This example hides the layer \c route:
 
     \code
@@ -1007,23 +1015,9 @@ void QMapboxGL::removeAnnotation(QMapbox::AnnotationID id)
         \li QVariantList
     \endtable
 */
-bool QMapboxGL::setLayoutProperty(const QString& layer, const QString& property_, const QVariant& value)
+bool QMapboxGL::setLayoutProperty(const QString& layer, const QString& propertyName, const QVariant& value)
 {
-    using namespace mbgl::style;
-
-    Layer* layer_ = d_ptr->mapObj->getStyle().getLayer(layer.toStdString());
-    if (!layer_) {
-        qWarning() << "Layer not found:" << layer;
-        return false;
-    }
-
-    auto result = conversion::setLayoutProperty(*layer_, property_.toStdString(), value);
-    if (result) {
-        qWarning() << "Error setting layout property" << property_ << "on layer" << layer << ":" << QString::fromStdString(result->message);
-        return false;
-    }
-
-    return true;
+    return d_ptr->setProperty(&mbgl::style::conversion::setLayoutProperty, layer, propertyName, value);
 }
 
 /*!
@@ -1031,6 +1025,10 @@ bool QMapboxGL::setLayoutProperty(const QString& layer, const QString& property_
     as defined by the \l {https://www.mapbox.com/mapbox-gl-style-spec/} {Mapbox style specification}
     for paint properties. Returns true if the operation succeeds, and false otherwise.
 
+    The implementation attempts to treat \a value as a JSON string, if the
+    QVariant inner type is a string. If not a valid JSON string, then it'll
+    proceed with the mapping described below.
+
     For paint properties that take a color as \a value, such as \c fill-color, a string such as
     \c blue can be passed or a QColor.
 
@@ -1076,23 +1074,10 @@ bool QMapboxGL::setLayoutProperty(const QString& layer, const QString& property_
         map->setPaintProperty("route","line-dasharray", lineDashArray);
     \endcode
 */
-bool QMapboxGL::setPaintProperty(const QString& layer, const QString& property_, const QVariant& value)
-{
-    using namespace mbgl::style;
-
-    Layer* layer_ = d_ptr->mapObj->getStyle().getLayer(layer.toStdString());
-    if (!layer_) {
-        qWarning() << "Layer not found:" << layer;
-        return false;
-    }
 
-    auto result = conversion::setPaintProperty(*layer_, property_.toStdString(), value);
-    if (result) {
-        qWarning() << "Error setting paint property" << property_ << "on layer" << layer << ":" << QString::fromStdString(result->message);
-        return false;
-    }
-
-    return true;
+bool QMapboxGL::setPaintProperty(const QString& layer, const QString& propertyName, const QVariant& value)
+{
+    return d_ptr->setProperty(&mbgl::style::conversion::setPaintProperty, layer, propertyName, value);
 }
 
 /*!
@@ -1917,3 +1902,38 @@ void QMapboxGLPrivate::requestRendering()
         emit needsRendering();
     }
 }
+
+bool QMapboxGLPrivate::setProperty(const PropertySetter& setter, const QString& layer, const QString& name, const QVariant& value) {
+    using namespace mbgl::style;
+
+    Layer* layerObject = mapObj->getStyle().getLayer(layer.toStdString());
+    if (!layerObject) {
+        qWarning() << "Layer not found:" << layer;
+        return false;
+    }
+
+    const std::string& propertyString = name.toStdString();
+
+    mbgl::optional<conversion::Error> result;
+
+    if (value.type() == QVariant::String) {
+        mbgl::JSDocument document;
+        document.Parse<0>(value.toString().toStdString());
+        if (!document.HasParseError()) {
+            // Treat value as a valid JSON.
+            const mbgl::JSValue* jsonValue = &document;
+            result = setter(*layerObject, propertyString, jsonValue);
+        } else {
+            result = setter(*layerObject, propertyString, value);
+        }
+    } else {
+        result = setter(*layerObject, propertyString, value);
+    }
+
+    if (result) {
+        qWarning() << "Error setting paint property" << name << "on layer" << layer << ":" << QString::fromStdString(result->message);
+        return false;
+    }
+
+    return true;
+}
diff --git a/platform/qt/src/qmapboxgl_p.hpp b/platform/qt/src/qmapboxgl_p.hpp
index 51c7cb8fc4..80789ac8f1 100644
--- a/platform/qt/src/qmapboxgl_p.hpp
+++ b/platform/qt/src/qmapboxgl_p.hpp
@@ -37,6 +37,9 @@ public:
     void render();
     void setFramebufferObject(quint32 fbo, const QSize& size);
 
+    using PropertySetter = std::function<mbgl::optional<mbgl::style::conversion::Error>(mbgl::style::Layer&, const std::string&, const mbgl::style::conversion::Convertible&)>;
+    bool setProperty(const PropertySetter& setter, const QString& layer, const QString& name, const QVariant& value);
+
     mbgl::EdgeInsets margins;
     std::unique_ptr<mbgl::Map> mapObj;