[android] expose offline database merge API

2 files changed, 84 insertions, 10 deletions

diff --git a/platform/android/src/offline/offline_manager.cpp b/platform/android/src/offline/offline_manager.cpp
index b27af8bdae..c6432f766a 100644
--- a/platform/android/src/offline/offline_manager.cpp
+++ b/platform/android/src/offline/offline_manager.cpp
@@ -34,7 +34,7 @@ void OfflineManager::listOfflineRegions(jni::JNIEnv& env_, const jni::Object<Fil
 
         if (regions) {
             OfflineManager::ListOfflineRegionsCallback::onList(
-                *env, *jFileSource, *callback, std::move(*regions));
+                *env, *jFileSource, *callback, *regions);
         } else {
             OfflineManager::ListOfflineRegionsCallback::onError(
                 *env, *callback, regions.error());
@@ -70,7 +70,7 @@ void OfflineManager::createOfflineRegion(jni::JNIEnv& env_,
 
         if (region) {
             OfflineManager::CreateOfflineRegionCallback::onCreate(
-                *env, *jFileSource, *callback, std::move(*region)
+                *env, *jFileSource, *callback, *region
             );
         } else {
             OfflineManager::CreateOfflineRegionCallback::onError(
@@ -79,9 +79,36 @@ void OfflineManager::createOfflineRegion(jni::JNIEnv& env_,
     });
 }
 
+void OfflineManager::mergeOfflineRegions(jni::JNIEnv& env_, const jni::Object<FileSource>& jFileSource_,
+                                         const jni::String& jString_,
+                                         const jni::Object<MergeOfflineRegionsCallback>& callback_) {
+    auto globalCallback = jni::NewGlobal<jni::EnvAttachingDeleter>(env_, callback_);
+    auto globalFilesource = jni::NewGlobal<jni::EnvAttachingDeleter>(env_, jFileSource_);
+
+    auto path = jni::Make<std::string>(env_, jString_);
+    fileSource.mergeOfflineRegions(path, [
+        //Keep a shared ptr to a global reference of the callback and file source so they are not GC'd in the meanwhile
+        callback = std::make_shared<decltype(globalCallback)>(std::move(globalCallback)),
+        jFileSource = std::make_shared<decltype(globalFilesource)>(std::move(globalFilesource))
+    ](mbgl::expected<mbgl::OfflineRegions, std::exception_ptr> regions) mutable {
+
+        // Reattach, the callback comes from a different thread
+        android::UniqueEnv env = android::AttachEnv();
+
+        if (regions) {
+            OfflineManager::MergeOfflineRegionsCallback::onMerge(
+                *env, *jFileSource, *callback, *regions);
+        } else {
+            OfflineManager::MergeOfflineRegionsCallback::onError(
+                *env, *callback, regions.error());
+        }
+    });
+}
+
 void OfflineManager::registerNative(jni::JNIEnv& env) {
     jni::Class<ListOfflineRegionsCallback>::Singleton(env);
     jni::Class<CreateOfflineRegionCallback>::Singleton(env);
+    jni::Class<MergeOfflineRegionsCallback>::Singleton(env);
 
     static auto& javaClass = jni::Class<OfflineManager>::Singleton(env);
 
@@ -93,7 +120,8 @@ void OfflineManager::registerNative(jni::JNIEnv& env) {
         "finalize",
         METHOD(&OfflineManager::setOfflineMapboxTileCountLimit, "setOfflineMapboxTileCountLimit"),
         METHOD(&OfflineManager::listOfflineRegions, "listOfflineRegions"),
-        METHOD(&OfflineManager::createOfflineRegion, "createOfflineRegion"));
+        METHOD(&OfflineManager::createOfflineRegion, "createOfflineRegion"),
+        METHOD(&OfflineManager::mergeOfflineRegions, "mergeOfflineRegions"));
 }
 
 // OfflineManager::ListOfflineRegionsCallback //
@@ -110,13 +138,13 @@ void OfflineManager::ListOfflineRegionsCallback::onError(jni::JNIEnv& env,
 void OfflineManager::ListOfflineRegionsCallback::onList(jni::JNIEnv& env,
                                                         const jni::Object<FileSource>& jFileSource,
                                                         const jni::Object<OfflineManager::ListOfflineRegionsCallback>& callback,
-                                                        mbgl::optional<std::vector<mbgl::OfflineRegion>> regions) {
+                                                        mbgl::OfflineRegions& regions) {
     static auto& javaClass = jni::Class<OfflineManager::ListOfflineRegionsCallback>::Singleton(env);
     static auto method = javaClass.GetMethod<void (jni::Array<jni::Object<OfflineRegion>>)>(env, "onList");
 
     std::size_t index = 0;
-    auto jregions = jni::Array<jni::Object<OfflineRegion>>::New(env, regions->size());
-    for (auto& region : *regions) {
+    auto jregions = jni::Array<jni::Object<OfflineRegion>>::New(env, regions.size());
+    for (auto& region : regions) {
         jregions.Set(env, index, OfflineRegion::New(env, jFileSource, std::move(region)));
         index++;
     }
@@ -138,11 +166,39 @@ void OfflineManager::CreateOfflineRegionCallback::onError(jni::JNIEnv& env,
 void OfflineManager::CreateOfflineRegionCallback::onCreate(jni::JNIEnv& env,
                                                         const jni::Object<FileSource>& jFileSource,
                                                         const jni::Object<OfflineManager::CreateOfflineRegionCallback>& callback,
-                                                        mbgl::optional<mbgl::OfflineRegion> region) {
+                                                        mbgl::OfflineRegion& region) {
     static auto& javaClass = jni::Class<OfflineManager::CreateOfflineRegionCallback>::Singleton(env);
     static auto method = javaClass.GetMethod<void (jni::Object<OfflineRegion>)>(env, "onCreate");
 
-    callback.Call(env, method, OfflineRegion::New(env, jFileSource, std::move(*region)));
+    callback.Call(env, method, OfflineRegion::New(env, jFileSource, std::move(region)));
+}
+
+// OfflineManager::MergeOfflineRegionsCallback //
+
+void OfflineManager::MergeOfflineRegionsCallback::onError(jni::JNIEnv& env,
+                                                          const jni::Object<OfflineManager::MergeOfflineRegionsCallback>& callback,
+                                                          std::exception_ptr error) {
+    static auto& javaClass = jni::Class<OfflineManager::MergeOfflineRegionsCallback>::Singleton(env);
+    static auto method = javaClass.GetMethod<void (jni::String)>(env, "onError");
+
+    callback.Call(env, method, jni::Make<jni::String>(env, mbgl::util::toString(error)));
+}
+
+void OfflineManager::MergeOfflineRegionsCallback::onMerge(jni::JNIEnv& env,
+                                                          const jni::Object<FileSource>& jFileSource,
+                                                          const jni::Object<MergeOfflineRegionsCallback>& callback,
+                                                          mbgl::OfflineRegions& regions) {
+    static auto& javaClass = jni::Class<OfflineManager::MergeOfflineRegionsCallback>::Singleton(env);
+    static auto method = javaClass.GetMethod<void (jni::Array<jni::Object<OfflineRegion>>)>(env, "onMerge");
+
+    std::size_t index = 0;
+    auto jregions = jni::Array<jni::Object<OfflineRegion>>::New(env, regions.size());
+    for (auto& region : regions) {
+        jregions.Set(env, index, OfflineRegion::New(env, jFileSource, std::move(region)));
+        index++;
+    }
+
+    callback.Call(env, method, jregions);
 }
 
 } // namespace android
diff --git a/platform/android/src/offline/offline_manager.hpp b/platform/android/src/offline/offline_manager.hpp
index 21ca5ca9c1..b2ebc63a63 100644
--- a/platform/android/src/offline/offline_manager.hpp
+++ b/platform/android/src/offline/offline_manager.hpp
@@ -8,6 +8,7 @@
 #include "../file_source.hpp"
 #include "offline_region.hpp"
 #include "offline_region_definition.hpp"
+#include "../java_types.hpp"
 
 
 namespace mbgl {
@@ -25,7 +26,7 @@ public:
         static void onList(jni::JNIEnv&,
                             const jni::Object<FileSource>&,
                             const jni::Object<OfflineManager::ListOfflineRegionsCallback>&,
-                            mbgl::optional<std::vector<mbgl::OfflineRegion>>);
+                            mbgl::OfflineRegions&);
     };
 
     class CreateOfflineRegionCallback {
@@ -37,7 +38,19 @@ public:
         static void onCreate(jni::JNIEnv&,
                             const jni::Object<FileSource>&,
                             const jni::Object<OfflineManager::CreateOfflineRegionCallback>&,
-                            mbgl::optional<mbgl::OfflineRegion>);
+                            mbgl::OfflineRegion&);
+    };
+
+    class MergeOfflineRegionsCallback {
+    public:
+        static constexpr auto Name() { return "com/mapbox/mapboxsdk/offline/OfflineManager$MergeOfflineRegionsCallback";}
+
+        static void onError(jni::JNIEnv&, const jni::Object<OfflineManager::MergeOfflineRegionsCallback>&, std::exception_ptr);
+
+        static void onMerge(jni::JNIEnv&,
+                            const jni::Object<FileSource>&,
+                            const jni::Object<MergeOfflineRegionsCallback>&,
+                            mbgl::OfflineRegions&);
     };
 
     static constexpr auto Name() { return "com/mapbox/mapboxsdk/offline/OfflineManager"; };
@@ -57,6 +70,11 @@ public:
                              const jni::Array<jni::jbyte>& metadata,
                              const jni::Object<OfflineManager::CreateOfflineRegionCallback>& callback);
 
+    void mergeOfflineRegions(jni::JNIEnv&,
+                             const jni::Object<FileSource>&,
+                             const jni::String&,
+                             const jni::Object<MergeOfflineRegionsCallback>&);
+
 private:
     mbgl::DefaultFileSource& fileSource;
 };