From 2b67ce73b6d313b518f55fc612fd647d9c540a4e Mon Sep 17 00:00:00 2001
From: Alexander Shalamov <alexander.shalamov@mapbox.com>
Date: Wed, 25 Mar 2020 10:38:03 +0200
Subject: [PATCH] [android] Expose getLayer, getSource and Observer interface
 for snapshotter

So that users can modify properties of an existing layer / source objects
---
 .../src/snapshotter/map_snapshotter.cpp       | 27 ++++++++++++
 .../src/snapshotter/map_snapshotter.hpp       |  2 +
 .../style/sources/custom_geometry_source.cpp  |  5 +--
 .../style/sources/custom_geometry_source.hpp  |  2 +-
 .../src/style/sources/geojson_source.cpp      |  2 +-
 .../src/style/sources/geojson_source.hpp      |  2 +-
 .../src/style/sources/image_source.cpp        |  7 +--
 .../src/style/sources/image_source.hpp        |  2 +-
 .../src/style/sources/raster_dem_source.cpp   |  7 ++-
 .../src/style/sources/raster_dem_source.hpp   |  2 +-
 .../src/style/sources/raster_source.cpp       |  7 +--
 .../src/style/sources/raster_source.hpp       |  2 +-
 platform/android/src/style/sources/source.cpp | 43 +++++++++++--------
 platform/android/src/style/sources/source.hpp |  3 +-
 .../src/style/sources/unknown_source.cpp      | 15 +++----
 .../src/style/sources/unknown_source.hpp      |  2 +-
 .../src/style/sources/vector_source.cpp       |  7 +--
 .../src/style/sources/vector_source.hpp       |  2 +-
 18 files changed, 82 insertions(+), 57 deletions(-)

diff --git a/platform/android/src/snapshotter/map_snapshotter.cpp b/platform/android/src/snapshotter/map_snapshotter.cpp
index 5bccbd1ba8b..a02c9e5c937 100644
--- a/platform/android/src/snapshotter/map_snapshotter.cpp
+++ b/platform/android/src/snapshotter/map_snapshotter.cpp
@@ -7,6 +7,7 @@
 #include <mbgl/util/string.hpp>
 
 #include "../attach_env.hpp"
+#include "../style/layers/layer_manager.hpp"
 #include "map_snapshot.hpp"
 
 namespace mbgl {
@@ -282,6 +283,30 @@ void MapSnapshotter::addImages(JNIEnv& env, const jni::Array<jni::Object<mbgl::a
     }
 }
 
+jni::Local<jni::Object<Layer>> MapSnapshotter::getLayer(JNIEnv& env, const jni::String& layerId) {
+    // Find the layer
+    mbgl::style::Layer* coreLayer = snapshotter->getStyle().getLayer(jni::Make<std::string>(env, layerId));
+    if (!coreLayer) {
+        mbgl::Log::Debug(mbgl::Event::JNI, "No layer found");
+        return jni::Local<jni::Object<Layer>>();
+    }
+
+    // Create and return the layer's native peer
+    return LayerManagerAndroid::get()->createJavaLayerPeer(env, *coreLayer);
+}
+
+jni::Local<jni::Object<Source>> MapSnapshotter::getSource(JNIEnv& env, const jni::String& sourceId) {
+    // Find the source
+    mbgl::style::Source* coreSource = snapshotter->getStyle().getSource(jni::Make<std::string>(env, sourceId));
+    if (!coreSource) {
+        mbgl::Log::Debug(mbgl::Event::JNI, "No source found");
+        return jni::Local<jni::Object<Source>>();
+    }
+
+    // Create and return the source's native peer
+    return jni::NewLocal(env, Source::peerForCoreSource(env, *coreSource));
+}
+
 // Static methods //
 
 void MapSnapshotter::registerNative(jni::JNIEnv& env) {
@@ -314,6 +339,8 @@ void MapSnapshotter::registerNative(jni::JNIEnv& env) {
                                             METHOD(&MapSnapshotter::addLayerAbove, "nativeAddLayerAbove"),
                                             METHOD(&MapSnapshotter::addSource, "nativeAddSource"),
                                             METHOD(&MapSnapshotter::addImages, "nativeAddImages"),
+                                            METHOD(&MapSnapshotter::getLayer, "nativeGetLayer"),
+                                            METHOD(&MapSnapshotter::getSource, "nativeGetSource"),
                                             METHOD(&MapSnapshotter::setStyleJson, "setStyleJson"),
                                             METHOD(&MapSnapshotter::setSize, "setSize"),
                                             METHOD(&MapSnapshotter::setCameraPosition, "setCameraPosition"),
diff --git a/platform/android/src/snapshotter/map_snapshotter.hpp b/platform/android/src/snapshotter/map_snapshotter.hpp
index c7a9ce14ad7..4d0186e7f8b 100644
--- a/platform/android/src/snapshotter/map_snapshotter.hpp
+++ b/platform/android/src/snapshotter/map_snapshotter.hpp
@@ -58,6 +58,8 @@ class MapSnapshotter final : public mbgl::MapSnapshotterObserver {
     void addLayerAbove(JNIEnv&, jlong, const jni::String&);
     void addSource(JNIEnv&, const jni::Object<Source>&, jlong nativePtr);
     void addImages(JNIEnv&, const jni::Array<jni::Object<mbgl::android::Image>>&);
+    jni::Local<jni::Object<Layer>> getLayer(JNIEnv&, const jni::String&);
+    jni::Local<jni::Object<Source>> getSource(JNIEnv&, const jni::String&);
 
     // MapSnapshotterObserver overrides
     void onDidFailLoadingStyle(const std::string&) override;
diff --git a/platform/android/src/style/sources/custom_geometry_source.cpp b/platform/android/src/style/sources/custom_geometry_source.cpp
index dccca4cf460..0d96a099165 100644
--- a/platform/android/src/style/sources/custom_geometry_source.cpp
+++ b/platform/android/src/style/sources/custom_geometry_source.cpp
@@ -51,9 +51,8 @@ namespace android {
 
     CustomGeometrySource::CustomGeometrySource(jni::JNIEnv& env,
                                                mbgl::style::Source& coreSource,
-                                               AndroidRendererFrontend& frontend)
-        : Source(env, coreSource, createJavaPeer(env), frontend) {
-    }
+                                               AndroidRendererFrontend* frontend)
+        : Source(env, coreSource, createJavaPeer(env), frontend) {}
 
     CustomGeometrySource::~CustomGeometrySource() {
         releaseThreads();
diff --git a/platform/android/src/style/sources/custom_geometry_source.hpp b/platform/android/src/style/sources/custom_geometry_source.hpp
index 52e4027dd86..6979ecc25d4 100644
--- a/platform/android/src/style/sources/custom_geometry_source.hpp
+++ b/platform/android/src/style/sources/custom_geometry_source.hpp
@@ -21,7 +21,7 @@ class CustomGeometrySource : public Source {
     static void registerNative(jni::JNIEnv&);
 
     CustomGeometrySource(jni::JNIEnv&, const jni::String&, const jni::Object<>&);
-    CustomGeometrySource(jni::JNIEnv&, mbgl::style::Source&, AndroidRendererFrontend&);
+    CustomGeometrySource(jni::JNIEnv&, mbgl::style::Source&, AndroidRendererFrontend*);
     ~CustomGeometrySource();
 
     bool removeFromMap(JNIEnv&, const jni::Object<Source>&, mbgl::Map&) override;
diff --git a/platform/android/src/style/sources/geojson_source.cpp b/platform/android/src/style/sources/geojson_source.cpp
index f68c9d8f425..0a287eb6da3 100644
--- a/platform/android/src/style/sources/geojson_source.cpp
+++ b/platform/android/src/style/sources/geojson_source.cpp
@@ -50,7 +50,7 @@ GeoJSONSource::GeoJSONSource(jni::JNIEnv& env, const jni::String& sourceId, cons
       converter(std::make_unique<Actor<FeatureConverter>>(Scheduler::GetBackground(),
                                                           source.as<style::GeoJSONSource>()->impl().getOptions())) {}
 
-GeoJSONSource::GeoJSONSource(jni::JNIEnv& env, mbgl::style::Source& coreSource, AndroidRendererFrontend& frontend)
+GeoJSONSource::GeoJSONSource(jni::JNIEnv& env, mbgl::style::Source& coreSource, AndroidRendererFrontend* frontend)
     : Source(env, coreSource, createJavaPeer(env), frontend),
       converter(std::make_unique<Actor<FeatureConverter>>(Scheduler::GetBackground(),
                                                           source.as<style::GeoJSONSource>()->impl().getOptions())) {}
diff --git a/platform/android/src/style/sources/geojson_source.hpp b/platform/android/src/style/sources/geojson_source.hpp
index 668e944e1cf..c7ef6e54dea 100644
--- a/platform/android/src/style/sources/geojson_source.hpp
+++ b/platform/android/src/style/sources/geojson_source.hpp
@@ -43,7 +43,7 @@ class GeoJSONSource : public Source {
     static void registerNative(jni::JNIEnv&);
 
     GeoJSONSource(jni::JNIEnv&, const jni::String&, const jni::Object<>&);
-    GeoJSONSource(jni::JNIEnv&, mbgl::style::Source&, AndroidRendererFrontend&);
+    GeoJSONSource(jni::JNIEnv&, mbgl::style::Source&, AndroidRendererFrontend*);
     ~GeoJSONSource();
 
 private:
diff --git a/platform/android/src/style/sources/image_source.cpp b/platform/android/src/style/sources/image_source.cpp
index b42e0e5a51d..448ecd21608 100644
--- a/platform/android/src/style/sources/image_source.cpp
+++ b/platform/android/src/style/sources/image_source.cpp
@@ -23,11 +23,8 @@ namespace android {
             ) {
     }
 
-    ImageSource::ImageSource(jni::JNIEnv& env,
-                             mbgl::style::Source& coreSource,
-                             AndroidRendererFrontend& frontend)
-            : Source(env, coreSource, createJavaPeer(env), frontend) {
-    }
+    ImageSource::ImageSource(jni::JNIEnv& env, mbgl::style::Source& coreSource, AndroidRendererFrontend* frontend)
+        : Source(env, coreSource, createJavaPeer(env), frontend) {}
 
     ImageSource::~ImageSource() = default;
 
diff --git a/platform/android/src/style/sources/image_source.hpp b/platform/android/src/style/sources/image_source.hpp
index 6c359bf0ee1..da88feac742 100644
--- a/platform/android/src/style/sources/image_source.hpp
+++ b/platform/android/src/style/sources/image_source.hpp
@@ -19,7 +19,7 @@ class ImageSource : public Source {
 
     ImageSource(jni::JNIEnv&, const jni::String&, const jni::Object<LatLngQuad>&);
 
-    ImageSource(jni::JNIEnv&, mbgl::style::Source&, AndroidRendererFrontend&);
+    ImageSource(jni::JNIEnv&, mbgl::style::Source&, AndroidRendererFrontend*);
 
     ~ImageSource();
 
diff --git a/platform/android/src/style/sources/raster_dem_source.cpp b/platform/android/src/style/sources/raster_dem_source.cpp
index f60526a9b75..a33e002598c 100644
--- a/platform/android/src/style/sources/raster_dem_source.cpp
+++ b/platform/android/src/style/sources/raster_dem_source.cpp
@@ -24,10 +24,9 @@ namespace android {
     }
 
     RasterDEMSource::RasterDEMSource(jni::JNIEnv& env,
-                               mbgl::style::Source& coreSource,
-                               AndroidRendererFrontend& frontend)
-         : Source(env, coreSource, createJavaPeer(env), frontend) {
-    }
+                                     mbgl::style::Source& coreSource,
+                                     AndroidRendererFrontend* frontend)
+        : Source(env, coreSource, createJavaPeer(env), frontend) {}
 
     RasterDEMSource::~RasterDEMSource() = default;
 
diff --git a/platform/android/src/style/sources/raster_dem_source.hpp b/platform/android/src/style/sources/raster_dem_source.hpp
index 0b31c4ecd3b..581e8f8bc67 100644
--- a/platform/android/src/style/sources/raster_dem_source.hpp
+++ b/platform/android/src/style/sources/raster_dem_source.hpp
@@ -15,7 +15,7 @@ class RasterDEMSource : public Source {
     static void registerNative(jni::JNIEnv&);
 
     RasterDEMSource(jni::JNIEnv&, const jni::String&, const jni::Object<>&, jni::jint);
-    RasterDEMSource(jni::JNIEnv&, mbgl::style::Source&, AndroidRendererFrontend&);
+    RasterDEMSource(jni::JNIEnv&, mbgl::style::Source&, AndroidRendererFrontend*);
     ~RasterDEMSource();
 
     jni::Local<jni::String> getURL(jni::JNIEnv&);
diff --git a/platform/android/src/style/sources/raster_source.cpp b/platform/android/src/style/sources/raster_source.cpp
index 535f899c99b..67603e74cdb 100644
--- a/platform/android/src/style/sources/raster_source.cpp
+++ b/platform/android/src/style/sources/raster_source.cpp
@@ -22,11 +22,8 @@ namespace android {
         ) {
     }
 
-    RasterSource::RasterSource(jni::JNIEnv& env,
-                               mbgl::style::Source& coreSource,
-                               AndroidRendererFrontend& frontend)
-        : Source(env, coreSource, createJavaPeer(env), frontend) {
-    }
+    RasterSource::RasterSource(jni::JNIEnv& env, mbgl::style::Source& coreSource, AndroidRendererFrontend* frontend)
+        : Source(env, coreSource, createJavaPeer(env), frontend) {}
 
     RasterSource::~RasterSource() = default;
 
diff --git a/platform/android/src/style/sources/raster_source.hpp b/platform/android/src/style/sources/raster_source.hpp
index 08648f79aad..e1bc5ca7aeb 100644
--- a/platform/android/src/style/sources/raster_source.hpp
+++ b/platform/android/src/style/sources/raster_source.hpp
@@ -15,7 +15,7 @@ class RasterSource : public Source {
     static void registerNative(jni::JNIEnv&);
 
     RasterSource(jni::JNIEnv&, const jni::String&, const jni::Object<>&, jni::jint);
-    RasterSource(jni::JNIEnv&, mbgl::style::Source&, AndroidRendererFrontend&);
+    RasterSource(jni::JNIEnv&, mbgl::style::Source&, AndroidRendererFrontend*);
     ~RasterSource();
 
     jni::Local<jni::String> getURL(jni::JNIEnv&);
diff --git a/platform/android/src/style/sources/source.cpp b/platform/android/src/style/sources/source.cpp
index f4040a57181..5c43c2ae7ca 100644
--- a/platform/android/src/style/sources/source.cpp
+++ b/platform/android/src/style/sources/source.cpp
@@ -34,33 +34,42 @@
 namespace mbgl {
 namespace android {
 
-    static std::unique_ptr<Source> createSourcePeer(jni::JNIEnv& env, mbgl::style::Source& coreSource, AndroidRendererFrontend& frontend) {
-        if (coreSource.is<mbgl::style::VectorSource>()) {
-            return std::make_unique<VectorSource>(env, *coreSource.as<mbgl::style::VectorSource>(), frontend);
-        } else if (coreSource.is<mbgl::style::RasterSource>()) {
-            return std::make_unique<RasterSource>(env, *coreSource.as<mbgl::style::RasterSource>(), frontend);
-        } else if (coreSource.is<mbgl::style::GeoJSONSource>()) {
-            return std::make_unique<GeoJSONSource>(env, *coreSource.as<mbgl::style::GeoJSONSource>(), frontend);
-        } else if (coreSource.is<mbgl::style::ImageSource>()) {
-            return std::make_unique<ImageSource>(env, *coreSource.as<mbgl::style::ImageSource>(), frontend);
-        } else {
-            return std::make_unique<UnknownSource>(env, coreSource, frontend);
-        }
+static std::unique_ptr<Source> createSourcePeer(jni::JNIEnv& env,
+                                                mbgl::style::Source& coreSource,
+                                                AndroidRendererFrontend* frontend) {
+    if (coreSource.is<mbgl::style::VectorSource>()) {
+        return std::make_unique<VectorSource>(env, *coreSource.as<mbgl::style::VectorSource>(), frontend);
+    } else if (coreSource.is<mbgl::style::RasterSource>()) {
+        return std::make_unique<RasterSource>(env, *coreSource.as<mbgl::style::RasterSource>(), frontend);
+    } else if (coreSource.is<mbgl::style::GeoJSONSource>()) {
+        return std::make_unique<GeoJSONSource>(env, *coreSource.as<mbgl::style::GeoJSONSource>(), frontend);
+    } else if (coreSource.is<mbgl::style::ImageSource>()) {
+        return std::make_unique<ImageSource>(env, *coreSource.as<mbgl::style::ImageSource>(), frontend);
+    } else {
+        return std::make_unique<UnknownSource>(env, coreSource, frontend);
     }
+}
 
     const jni::Object<Source>& Source::peerForCoreSource(jni::JNIEnv& env, mbgl::style::Source& coreSource, AndroidRendererFrontend& frontend) {
         if (!coreSource.peer.has_value()) {
-            coreSource.peer = createSourcePeer(env, coreSource, frontend);
+            coreSource.peer = createSourcePeer(env, coreSource, &frontend);
         }
         return coreSource.peer.get<std::unique_ptr<Source>>()->javaPeer;
     }
 
-    Source::Source(jni::JNIEnv& env, mbgl::style::Source& coreSource, const jni::Object<Source>& obj, AndroidRendererFrontend& frontend)
-        : source(coreSource)
-        , javaPeer(jni::NewGlobal(env, obj))
-        , rendererFrontend(&frontend) {
+    const jni::Object<Source>& Source::peerForCoreSource(jni::JNIEnv& env, mbgl::style::Source& coreSource) {
+        if (!coreSource.peer.has_value()) {
+            coreSource.peer = createSourcePeer(env, coreSource, nullptr);
+        }
+        return coreSource.peer.get<std::unique_ptr<Source>>()->javaPeer;
     }
 
+    Source::Source(jni::JNIEnv& env,
+                   mbgl::style::Source& coreSource,
+                   const jni::Object<Source>& obj,
+                   AndroidRendererFrontend* frontend)
+        : source(coreSource), javaPeer(jni::NewGlobal(env, obj)), rendererFrontend(frontend) {}
+
     Source::Source(jni::JNIEnv&, std::unique_ptr<mbgl::style::Source> coreSource)
         : ownedSource(std::move(coreSource))
         , source(*ownedSource) {
diff --git a/platform/android/src/style/sources/source.hpp b/platform/android/src/style/sources/source.hpp
index a87972ce792..e0f2b2229f8 100644
--- a/platform/android/src/style/sources/source.hpp
+++ b/platform/android/src/style/sources/source.hpp
@@ -19,12 +19,13 @@ class Source : private mbgl::util::noncopyable {
 
     static void registerNative(jni::JNIEnv&);
 
+    static const jni::Object<Source>& peerForCoreSource(jni::JNIEnv&, mbgl::style::Source&);
     static const jni::Object<Source>& peerForCoreSource(jni::JNIEnv&, mbgl::style::Source&, AndroidRendererFrontend&);
 
     /*
      * Called when a Java object is created for a core source that belongs to a map.
      */
-    Source(jni::JNIEnv&, mbgl::style::Source&, const jni::Object<Source>&, AndroidRendererFrontend&);
+    Source(jni::JNIEnv&, mbgl::style::Source&, const jni::Object<Source>&, AndroidRendererFrontend*);
 
     /*
      * Called when a Java object is created for a new core source that does not belong to a map.
diff --git a/platform/android/src/style/sources/unknown_source.cpp b/platform/android/src/style/sources/unknown_source.cpp
index b5285a5f9f6..1a0e3d4f821 100644
--- a/platform/android/src/style/sources/unknown_source.cpp
+++ b/platform/android/src/style/sources/unknown_source.cpp
@@ -12,16 +12,13 @@ namespace {
 namespace mbgl {
 namespace android {
 
-    UnknownSource::UnknownSource(jni::JNIEnv& env,
-                                 mbgl::style::Source& coreSource,
-                                 AndroidRendererFrontend& frontend)
-        : Source(env, coreSource, createJavaPeer(env), frontend) {
-    }
+UnknownSource::UnknownSource(jni::JNIEnv& env, mbgl::style::Source& coreSource, AndroidRendererFrontend* frontend)
+    : Source(env, coreSource, createJavaPeer(env), frontend) {}
 
-    jni::Local<jni::Object<Source>> UnknownSource::createJavaPeer(jni::JNIEnv& env) {
-        static auto& javaClass = jni::Class<UnknownSource>::Singleton(env);
-        static auto constructor = javaClass.GetConstructor<jni::jlong>(env);
-        return javaClass.New(env, constructor, reinterpret_cast<jni::jlong>(this));
+jni::Local<jni::Object<Source>> UnknownSource::createJavaPeer(jni::JNIEnv& env) {
+    static auto& javaClass = jni::Class<UnknownSource>::Singleton(env);
+    static auto constructor = javaClass.GetConstructor<jni::jlong>(env);
+    return javaClass.New(env, constructor, reinterpret_cast<jni::jlong>(this));
     }
 
     void UnknownSource::registerNative(jni::JNIEnv& env) {
diff --git a/platform/android/src/style/sources/unknown_source.hpp b/platform/android/src/style/sources/unknown_source.hpp
index f042e2042c4..ab5a2da82f5 100644
--- a/platform/android/src/style/sources/unknown_source.hpp
+++ b/platform/android/src/style/sources/unknown_source.hpp
@@ -14,7 +14,7 @@ class UnknownSource : public Source {
 
     static void registerNative(jni::JNIEnv&);
 
-    UnknownSource(jni::JNIEnv&, mbgl::style::Source&, AndroidRendererFrontend&);
+    UnknownSource(jni::JNIEnv&, mbgl::style::Source&, AndroidRendererFrontend*);
 
     ~UnknownSource() = default;
 
diff --git a/platform/android/src/style/sources/vector_source.cpp b/platform/android/src/style/sources/vector_source.cpp
index e46fc1a94ec..2be1a78119a 100644
--- a/platform/android/src/style/sources/vector_source.cpp
+++ b/platform/android/src/style/sources/vector_source.cpp
@@ -30,11 +30,8 @@ namespace android {
         ) {
     }
 
-    VectorSource::VectorSource(jni::JNIEnv& env,
-                               mbgl::style::Source& coreSource,
-                               AndroidRendererFrontend& frontend)
-        : Source(env, coreSource, createJavaPeer(env), frontend) {
-    }
+    VectorSource::VectorSource(jni::JNIEnv& env, mbgl::style::Source& coreSource, AndroidRendererFrontend* frontend)
+        : Source(env, coreSource, createJavaPeer(env), frontend) {}
 
     VectorSource::~VectorSource() = default;
 
diff --git a/platform/android/src/style/sources/vector_source.hpp b/platform/android/src/style/sources/vector_source.hpp
index 4cb46c6c620..7ae2e8c9e74 100644
--- a/platform/android/src/style/sources/vector_source.hpp
+++ b/platform/android/src/style/sources/vector_source.hpp
@@ -16,7 +16,7 @@ class VectorSource : public Source {
     static void registerNative(jni::JNIEnv&);
 
     VectorSource(jni::JNIEnv&, const jni::String&, const jni::Object<>&);
-    VectorSource(jni::JNIEnv&, mbgl::style::Source&, AndroidRendererFrontend&);
+    VectorSource(jni::JNIEnv&, mbgl::style::Source&, AndroidRendererFrontend*);
     ~VectorSource();
 
 private: