[WIP] wrap statement in filter and start replacing get filter nested conditional with visitor

9 files changed, 51 insertions, 72 deletions

diff --git a/platform/android/MapboxGLAndroidSDK/src/main/java/com/mapbox/mapboxsdk/style/layers/layer.java.ejs b/platform/android/MapboxGLAndroidSDK/src/main/java/com/mapbox/mapboxsdk/style/layers/layer.java.ejs
index 6206e30be5..b20f284387 100644
--- a/platform/android/MapboxGLAndroidSDK/src/main/java/com/mapbox/mapboxsdk/style/layers/layer.java.ejs
+++ b/platform/android/MapboxGLAndroidSDK/src/main/java/com/mapbox/mapboxsdk/style/layers/layer.java.ejs
@@ -9,6 +9,7 @@ package com.mapbox.mapboxsdk.style.layers;
 
 import android.support.annotation.ColorInt;
 import android.support.annotation.NonNull;
+import android.support.annotation.Nullable;
 import android.support.annotation.UiThread;
 
 import static com.mapbox.mapboxsdk.utils.ColorUtils.rgbaToColor;
@@ -91,8 +92,9 @@ public class <%- camelize(type) %>Layer extends Layer {
   /**
    * Gets the filter of the layer.
    *
-   * @return {@link Filter.Statement} filter layer is using
+   * @return {@link Filter.Statement} filter layer is using or null
    */
+  @Nullable
   public Filter.Statement getFilter() {
     return nativeGetFilter();
   }
diff --git a/platform/android/config.cmake b/platform/android/config.cmake
index ef364e8226..087a5ef2f8 100644
--- a/platform/android/config.cmake
+++ b/platform/android/config.cmake
@@ -113,8 +113,6 @@ add_library(mbgl-android STATIC
     platform/android/src/style/conversion/types_string_values.hpp
     platform/android/src/style/filter.cpp
     platform/android/src/style/filter.hpp
-    platform/android/src/style/statement.cpp
-    platform/android/src/style/statement.hpp
     platform/android/src/map/camera_position.cpp
     platform/android/src/map/camera_position.hpp
 
diff --git a/platform/android/src/style/conversion/filter.hpp b/platform/android/src/style/conversion/filter.hpp
index 229ddbf296..9f29a4dc08 100644
--- a/platform/android/src/style/conversion/filter.hpp
+++ b/platform/android/src/style/conversion/filter.hpp
@@ -2,7 +2,6 @@
 
 #include "../android_conversion.hpp"
 #include "../filter.hpp"
-#include "../statement.hpp"
 #include "../../conversion/conversion.hpp"
 #include <mbgl/style/conversion.hpp>
 #include <mbgl/style/conversion/filter.hpp>
@@ -31,12 +30,10 @@ inline optional<mbgl::style::Filter> toFilter(jni::JNIEnv& env, jni::Array<jni::
 }
 
 template <>
-struct Converter<jni::Object<mbgl::android::Statement>, mbgl::style::Filter> {
-    Result<jni::Object<mbgl::android::Statement>> operator()(jni::JNIEnv& env, const mbgl::style::Filter& value) const {
+struct Converter<jni::Object<mbgl::android::Filter::Statement>, mbgl::style::Filter> {
+    Result<jni::Object<mbgl::android::Filter::Statement>> operator()(jni::JNIEnv& env, const mbgl::style::Filter& value) const {
         using namespace mbgl::android;
-        auto statement = Filter::fromFilter(env, value);
-
-        return statement;
+        return Filter::fromFilter(env, value);
     }
 };
 
diff --git a/platform/android/src/style/filter.cpp b/platform/android/src/style/filter.cpp
index 73c10cd775..3e5c28c08f 100644
--- a/platform/android/src/style/filter.cpp
+++ b/platform/android/src/style/filter.cpp
@@ -3,19 +3,19 @@
 namespace mbgl {
 namespace android {
 
-jni::Object<Statement> Filter::fromFilter(jni::JNIEnv& env, const mbgl::style::Filter&) {
-    static auto constructor = Statement::javaClass.template GetConstructor<>(env);
-
-    return Statement::javaClass.New(env, constructor);
+jni::Object<Filter::Statement> Filter::fromFilter(jni::JNIEnv& env, const mbgl::style::Filter&) {
+    static auto constructor = Filter::Statement::javaClass.template GetConstructor<>(env);
+    return Filter::Statement::javaClass.New(env, constructor);
 }
 
+jni::Class<Filter> Filter::javaClass;
+
+jni::Class<Filter::Statement> Filter::Statement::javaClass;
+
 void Filter::registerNative(jni::JNIEnv& env) {
-    // Lookup the class
     Filter::javaClass = *jni::Class<Filter>::Find(env).NewGlobalRef(env).release();
+    Filter::Statement::javaClass = *jni::Class<Filter::Statement>::Find(env).NewGlobalRef(env).release();
 }
 
-jni::Class<Filter> Filter::javaClass;
-
-
 } // namespace android
 } // namespace mbgl
\ No newline at end of file
diff --git a/platform/android/src/style/filter.hpp b/platform/android/src/style/filter.hpp
index 959ab90f1f..bfd8838f3d 100644
--- a/platform/android/src/style/filter.hpp
+++ b/platform/android/src/style/filter.hpp
@@ -4,7 +4,6 @@
 #include <mbgl/util/noncopyable.hpp>
 
 #include <jni/jni.hpp>
-#include "statement.hpp"
 
 namespace mbgl {
 namespace android {
@@ -14,12 +13,18 @@ public:
 
     static constexpr auto Name() { return "com/mapbox/mapboxsdk/style/layers/Filter"; };
 
-    static jni::Object<Statement> fromFilter(jni::JNIEnv&, const mbgl::style::Filter&);
+    static jni::Object<Filter::Statement> fromFilter(jni::JNIEnv&, const mbgl::style::Filter&);
 
     static jni::Class<Filter> javaClass;
 
     static void registerNative(jni::JNIEnv&);
 
+    class Statement : private mbgl::util::noncopyable {
+    public:
+        static constexpr auto Name() { return "com/mapbox/mapboxsdk/style/layers/Filter$Statement"; };
+
+        static jni::Class<Filter::Statement> javaClass;
+    };
 };
 
 } // namespace android
diff --git a/platform/android/src/style/layers/layer.cpp b/platform/android/src/style/layers/layer.cpp
index 4fa0d1a690..c01745e879 100644
--- a/platform/android/src/style/layers/layer.cpp
+++ b/platform/android/src/style/layers/layer.cpp
@@ -99,36 +99,52 @@ namespace android {
         }
     }
 
-    struct SetFilterEvaluator {
-        style::Filter filter;
+    struct GetFilterEvaluator {
+        std::string noop(std::string layerType) {
+            Log::Warning(mbgl::Event::JNI, "%s doesn't support filters", layerType.c_str());
+            return {};
+        }
 
-        void operator()(style::BackgroundLayer&) { Log::Warning(mbgl::Event::JNI, "BackgroundLayer doesn't support filters"); }
-        void operator()(style::CustomLayer&) { Log::Warning(mbgl::Event::JNI, "CustomLayer doesn't support filters"); }
-        void operator()(style::RasterLayer&) { Log::Warning(mbgl::Event::JNI, "RasterLayer doesn't support filters"); }
+        std::string operator()(style::BackgroundLayer&) { return noop("BackgroundLayer doesn't support filters"); }
+        std::string operator()(style::CustomLayer&) { return noop("CustomLayer doesn't support filters"); }
+        std::string operator()(style::RasterLayer&) { return noop("RasterLayer doesn't support filters"); }
 
         template <class LayerType>
-        void operator()(LayerType& layer) {
-            layer.setFilter(filter);
+        std::string operator()(LayerType& layer) {
+            return layer.getSourceLayer();
         }
     };
 
-    jni::Object<mbgl::android::Statement> Layer::getFilter(jni::JNIEnv& env) {
+    jni::Object<mbgl::android::Filter::Statement> Layer::getFilter(jni::JNIEnv& env) {
         using namespace mbgl::style;
         using namespace mbgl::android::conversion;
 
         if (layer.is<FillLayer>()) {
-            return *convert<jni::Object<mbgl::android::Statement>, mbgl::style::Filter>(env, layer.as<FillLayer>()->getFilter());
+            return *convert<jni::Object<mbgl::android::Filter::Statement>, mbgl::style::Filter>(env, layer.as<FillLayer>()->getFilter());
         } else if (layer.is<LineLayer>()) {
-            return *convert<jni::Object<mbgl::android::Statement>, mbgl::style::Filter>(env, layer.as<LineLayer>()->getFilter());
+            return *convert<jni::Object<mbgl::android::Filter::Statement>, mbgl::style::Filter>(env, layer.as<LineLayer>()->getFilter());
         } else if (layer.is<SymbolLayer>()) {
-            return *convert<jni::Object<mbgl::android::Statement>, mbgl::style::Filter>(env, layer.as<SymbolLayer>()->getFilter());
+            return *convert<jni::Object<mbgl::android::Filter::Statement>, mbgl::style::Filter>(env, layer.as<SymbolLayer>()->getFilter());
         } else if (layer.is<CircleLayer>()) {
-            return *convert<jni::Object<mbgl::android::Statement>, mbgl::style::Filter>(env, layer.as<CircleLayer>()->getFilter());
+            return *convert<jni::Object<mbgl::android::Filter::Statement>, mbgl::style::Filter>(env, layer.as<CircleLayer>()->getFilter());
         } else {
-            return *convert<jni::Object<mbgl::android::Statement>, mbgl::style::Filter>(env, NullFilter());
+            return *convert<jni::Object<mbgl::android::Filter::Statement>, mbgl::style::Filter>(env, NullFilter());
         }
     }
 
+    struct SetFilterEvaluator {
+        style::Filter filter;
+
+        void operator()(style::BackgroundLayer&) { Log::Warning(mbgl::Event::JNI, "BackgroundLayer doesn't support filters"); }
+        void operator()(style::CustomLayer&) { Log::Warning(mbgl::Event::JNI, "CustomLayer doesn't support filters"); }
+        void operator()(style::RasterLayer&) { Log::Warning(mbgl::Event::JNI, "RasterLayer doesn't support filters"); }
+
+        template <class LayerType>
+        void operator()(LayerType& layer) {
+            layer.setFilter(filter);
+        }
+    };
+
     void Layer::setFilter(jni::JNIEnv& env, jni::Array<jni::Object<>> jfilter) {
         using namespace mbgl::style;
         using namespace mbgl::style::conversion;
diff --git a/platform/android/src/style/layers/layer.hpp b/platform/android/src/style/layers/layer.hpp
index aff08406dc..d72b294508 100644
--- a/platform/android/src/style/layers/layer.hpp
+++ b/platform/android/src/style/layers/layer.hpp
@@ -6,7 +6,6 @@
 
 #include "../value.hpp"
 #include "../filter.hpp"
-#include "../statement.hpp"
 
 #include <jni/jni.hpp>
 
@@ -68,7 +67,7 @@ public:
 
     /* common properties, but not shared by all */
 
-    jni::Object<mbgl::android::Statement> getFilter(jni::JNIEnv&);
+    jni::Object<mbgl::android::Filter::Statement> getFilter(jni::JNIEnv&);
 
     void setFilter(jni::JNIEnv&, jni::Array<jni::Object<>>);
 
diff --git a/platform/android/src/style/statement.cpp b/platform/android/src/style/statement.cpp
deleted file mode 100644
index f63a800297..0000000000
--- a/platform/android/src/style/statement.cpp
+++ /dev/null
@@ -1,15 +0,0 @@
-#include "statement.hpp"
-
-namespace mbgl {
-namespace android {
-
-void Statement::registerNative(jni::JNIEnv& env) {
-    // Lookup the class
-    Statement::javaClass = *jni::Class<Statement>::Find(env).NewGlobalRef(env).release();
-}
-
-jni::Class<Statement> Statement::javaClass;
-
-
-} // namespace android
-} // namespace mbgl
\ No newline at end of file
diff --git a/platform/android/src/style/statement.hpp b/platform/android/src/style/statement.hpp
deleted file mode 100644
index cd74ca898c..0000000000
--- a/platform/android/src/style/statement.hpp
+++ /dev/null
@@ -1,23 +0,0 @@
-#pragma once
-
-#include <mbgl/style/filter.hpp>
-#include <mbgl/util/noncopyable.hpp>
-
-#include <jni/jni.hpp>
-
-namespace mbgl {
-namespace android {
-
-class Statement : private mbgl::util::noncopyable {
-public:
-
-    static constexpr auto Name() { return "com/mapbox/mapboxsdk/style/layers/Filter$Statement"; };
-
-    static jni::Class<Statement> javaClass;
-
-    static void registerNative(jni::JNIEnv&);
-
-};
-
-} // namespace android
-} // namespace mbgl
\ No newline at end of file