JUCE/modules/juce_gui_basics/native/juce_ContentSharer_android.cpp

/*
  ==============================================================================

   This file is part of the JUCE library.
   Copyright (c) 2022 - Raw Material Software Limited

   JUCE is an open source library subject to commercial or open-source
   licensing.

   By using JUCE, you agree to the terms of both the JUCE 7 End-User License
   Agreement and JUCE Privacy Policy.

   End User License Agreement: www.juce.com/juce-7-licence
   Privacy Policy: www.juce.com/juce-privacy-policy

   Or: You may also use this code under the terms of the GPL v3 (see
   www.gnu.org/licenses).

   JUCE IS PROVIDED "AS IS" WITHOUT ANY WARRANTY, AND ALL WARRANTIES, WHETHER
   EXPRESSED OR IMPLIED, INCLUDING MERCHANTABILITY AND FITNESS FOR PURPOSE, ARE
   DISCLAIMED.

  ==============================================================================
*/
namespace juce
{

//==============================================================================
// This byte-code is generated from native/java/app/com/rmsl/juce/JuceContentProviderCursor.java with min sdk version 16
// See juce_core/native/java/README.txt on how to generate this byte-code.
static const uint8 javaJuceContentProviderCursor[] =
{31,139,8,8,191,114,161,94,0,3,106,97,118,97,74,117,99,101,67,111,110,116,101,110,116,80,114,111,118,105,100,101,114,67,117,
114,115,111,114,46,100,101,120,0,117,147,177,111,211,64,20,198,223,157,157,148,150,54,164,192,208,14,64,144,16,18,67,235,138,2,
75,40,162,10,44,150,65,149,2,25,218,233,176,173,198,37,241,69,182,19,121,96,160,21,136,37,19,98,234,80,85,149,152,88,24,248,
3,24,146,63,130,141,137,129,13,169,99,7,190,203,157,33,18,194,210,207,247,222,229,189,239,157,206,95,130,48,159,91,91,191,75,227,
60,200,143,134,239,247,151,62,189,43,175,127,249,246,235,241,215,241,112,231,231,193,237,135,22,81,143,136,242,214,157,139,
100,158,99,78,84,37,189,95,2,159,129,13,70,128,129,83,179,127,102,242,27,120,157,129,71,224,16,156,128,143,96,12,126,128,69,232,
93,6,75,224,10,184,14,238,129,13,224,130,16,188,4,3,174,245,44,51,79,205,152,53,171,101,206,86,54,241,27,20,206,152,120,136,
248,156,137,63,32,134,12,45,76,206,166,187,148,230,28,169,125,62,201,249,159,156,209,188,201,23,77,93,241,187,122,134,38,40,225,
52,42,124,197,245,252,94,141,104,147,182,113,95,21,76,208,83,222,114,125,86,89,101,168,109,162,162,183,134,46,86,249,71,215,
158,228,54,149,239,71,113,148,61,32,230,210,85,183,239,135,13,25,103,97,156,109,37,114,16,5,97,210,232,39,169,76,86,247,196,64,
208,53,79,196,65,34,163,192,9,68,38,94,136,52,116,158,136,44,137,114,93,84,167,91,158,47,187,78,210,77,59,206,30,164,156,255,
234,213,137,181,136,183,92,178,90,174,135,192,163,75,59,158,154,225,116,68,188,235,52,33,26,239,214,169,228,119,100,26,210,121,
95,118,250,221,248,169,232,134,41,45,251,90,176,217,22,73,33,215,80,101,1,217,109,153,102,52,171,222,207,228,115,52,218,89,
59,74,233,38,191,48,63,83,217,88,161,85,194,178,141,139,224,184,28,190,255,218,30,113,126,192,201,98,223,249,130,185,27,54,181,
22,222,227,83,254,43,60,49,50,235,180,15,11,47,150,167,252,200,106,186,95,121,146,85,255,122,134,215,180,190,242,169,101,106,
212,119,165,154,238,157,124,243,170,142,213,255,224,55,143,234,50,200,64,3,0,0,0,0};

// This byte-code is generated from native/java/app/com/rmsl/juce/JuceContentProviderFileObserver.java with min sdk version 16
// See juce_core/native/java/README.txt on how to generate this byte-code.
static const uint8 javaJuceContentProviderFileObserver[] =
{31,139,8,8,194,122,161,94,0,3,106,97,118,97,74,117,99,101,67,111,110,116,101,110,116,80,114,111,118,105,100,101,114,70,105,
108,101,79,98,115,101,114,118,101,114,46,100,101,120,0,133,147,205,107,19,65,24,198,223,249,72,98,171,46,105,235,69,16,201,65,81,
68,221,136,10,66,84,144,250,65,194,130,197,212,32,5,15,155,100,104,182,38,187,97,119,141,241,32,126,30,196,147,23,79,246,216,
131,120,202,77,169,80,212,191,64,193,66,143,30,60,138,255,130,62,179,51,165,219,147,129,223,188,239,188,239,204,179,179,179,79,
186,106,60,93,61,123,158,54,159,255,248,112,97,210,120,124,98,237,251,177,7,109,245,115,253,225,198,159,47,243,171,135,198,130,
104,72,68,227,214,185,89,178,191,45,78,116,128,76,189,8,62,3,169,235,128,129,61,204,204,203,204,204,171,24,142,99,207,2,226,
4,124,4,159,192,6,248,5,254,130,42,250,87,193,13,224,129,91,224,14,184,11,30,129,23,224,21,120,3,222,130,53,240,158,27,125,110,
159,95,176,231,41,233,51,216,249,75,44,152,178,249,107,228,211,54,95,69,190,215,230,239,144,11,40,57,153,150,200,222,81,100,
170,166,190,47,139,68,51,185,200,237,93,8,27,191,218,66,17,138,186,54,225,230,44,195,42,209,149,194,18,238,206,201,58,250,121,
235,182,215,172,160,191,200,137,159,113,172,158,204,246,50,251,62,38,151,89,103,251,29,139,23,131,48,72,47,19,171,19,107,208,
145,198,253,142,154,143,194,84,133,233,66,28,141,130,174,138,175,7,125,117,179,157,168,120,164,226,211,43,254,200,167,131,158,
31,118,227,40,232,186,81,226,230,219,53,114,189,78,52,112,227,65,210,119,87,32,229,254,71,175,70,179,158,150,116,251,126,184,
236,54,211,56,8,151,107,196,90,36,90,117,143,100,171,97,70,175,142,2,134,195,29,35,213,236,249,241,110,161,107,35,148,169,160,
178,32,123,81,146,210,148,30,23,163,219,137,34,57,240,147,123,84,138,66,179,76,14,253,180,71,50,237,5,9,29,21,229,185,153,146,
115,233,20,157,228,206,92,201,89,194,21,113,70,156,61,125,34,191,113,246,12,223,143,253,198,101,237,183,223,133,229,226,182,103,
121,206,183,34,231,93,153,243,111,129,118,60,92,164,29,31,179,138,217,175,189,204,202,102,141,246,24,175,24,125,237,111,97,
215,104,15,80,197,236,205,252,81,54,185,254,255,252,3,243,31,208,130,120,3,0,0,0,0};

//==============================================================================
#define JNI_CLASS_MEMBERS(METHOD, STATICMETHOD, FIELD, STATICFIELD, CALLBACK) \
 FIELD (authority, "authority", "Ljava/lang/String;")

DECLARE_JNI_CLASS (AndroidProviderInfo, "android/content/pm/ProviderInfo")
#undef JNI_CLASS_MEMBERS

#define JNI_CLASS_MEMBERS(METHOD, STATICMETHOD, FIELD, STATICFIELD, CALLBACK) \
 METHOD (constructor,       "<init>",            "(Landroid/os/ParcelFileDescriptor;JJ)V") \
 METHOD (createInputStream, "createInputStream", "()Ljava/io/FileInputStream;") \
 METHOD (getLength,         "getLength",         "()J")

DECLARE_JNI_CLASS (AssetFileDescriptor, "android/content/res/AssetFileDescriptor")
#undef JNI_CLASS_MEMBERS

#define JNI_CLASS_MEMBERS(METHOD, STATICMETHOD, FIELD, STATICFIELD, CALLBACK) \
 METHOD (close, "close", "()V")

DECLARE_JNI_CLASS (JavaCloseable, "java/io/Closeable")
#undef JNI_CLASS_MEMBERS

#define JNI_CLASS_MEMBERS(METHOD, STATICMETHOD, FIELD, STATICFIELD, CALLBACK) \
 STATICMETHOD (open, "open", "(Ljava/io/File;I)Landroid/os/ParcelFileDescriptor;")

DECLARE_JNI_CLASS (ParcelFileDescriptor, "android/os/ParcelFileDescriptor")
#undef JNI_CLASS_MEMBERS

//==============================================================================
class AndroidContentSharerCursor
{
public:
    AndroidContentSharerCursor (JNIEnv* env,
                                const LocalRef<jobject>& contentProvider,
                                const LocalRef<jobjectArray>& resultColumns,
                                std::function<void (AndroidContentSharerCursor&)> onCloseIn)
        : onClose (std::move (onCloseIn)),
          cursor (GlobalRef (LocalRef<jobject> (env->NewObject (JuceContentProviderCursor,
                                                                JuceContentProviderCursor.constructor,
                                                                reinterpret_cast<jlong> (this),
                                                                resultColumns.get()))))
    {
        // the content provider must be created first
        jassert (contentProvider.get() != nullptr);
    }

    jobject getNativeCursor() const { return cursor.get(); }

    void addRow (LocalRef<jobjectArray>& values)
    {
        auto* env = getEnv();

        env->CallVoidMethod (cursor.get(), JuceContentProviderCursor.addRow, values.get());
    }

private:
    static void cursorClosed (JNIEnv*, AndroidContentSharerCursor& t)
    {
        MessageManager::callAsync ([&t]
                                   {
                                       NullCheckedInvocation::invoke (t.onClose, t);
                                   });
    }

    std::function<void (AndroidContentSharerCursor&)> onClose;
    GlobalRef cursor;

    //==============================================================================
    #define JNI_CLASS_MEMBERS(METHOD, STATICMETHOD, FIELD, STATICFIELD, CALLBACK) \
     METHOD (addRow,      "addRow", "([Ljava/lang/Object;)V") \
     METHOD (constructor, "<init>", "(J[Ljava/lang/String;)V") \
     CALLBACK (generatedCallback<&AndroidContentSharerCursor::cursorClosed>, "contentSharerCursorClosed", "(J)V") \

    DECLARE_JNI_CLASS_WITH_BYTECODE (JuceContentProviderCursor, "com/rmsl/juce/JuceContentProviderCursor", 16, javaJuceContentProviderCursor)
    #undef JNI_CLASS_MEMBERS
};

//==============================================================================
class AndroidContentSharerFileObserver
{
public:
    AndroidContentSharerFileObserver (JNIEnv* env,
                                      const LocalRef<jobject>& contentProvider,
                                      const File& filepathToUse,
                                      std::function<void()> onCloseIn)
        : onClose (std::move (onCloseIn)),
          filepath (filepathToUse),
          fileObserver (GlobalRef (LocalRef<jobject> (env->NewObject (JuceContentProviderFileObserver,
                                                                      JuceContentProviderFileObserver.constructor,
                                                                      reinterpret_cast<jlong> (this),
                                                                      javaString (filepath.getFullPathName()).get(),
                                                                      open | access | closeWrite | closeNoWrite))))
    {
        // the content provider must be created first
        jassert (contentProvider.get() != nullptr);

        env->CallVoidMethod (fileObserver, JuceContentProviderFileObserver.startWatching);
    }

    void onFileEvent (int event, const LocalRef<jstring>&)
    {
        if (event == open)
        {
            ++numOpenedHandles;
        }
        else if (event == access)
        {
            fileWasRead = true;
        }
        else if (event == closeNoWrite || event == closeWrite)
        {
            --numOpenedHandles;

            // numOpenedHandles may get negative if we don't receive open handle event.
            if (fileWasRead && numOpenedHandles <= 0)
            {
                MessageManager::callAsync ([fileObserver = fileObserver, onClose = onClose]
                {
                    getEnv()->CallVoidMethod (fileObserver, JuceContentProviderFileObserver.stopWatching);
                    NullCheckedInvocation::invoke (onClose);
                });
            }
        }
    }

private:
    static constexpr int open = 32;
    static constexpr int access = 1;
    static constexpr int closeWrite = 8;
    static constexpr int closeNoWrite = 16;

    std::function<void()> onClose;
    bool fileWasRead = false;
    int numOpenedHandles = 0;

    File filepath;
    GlobalRef fileObserver;

    //==============================================================================
    #define JNI_CLASS_MEMBERS(METHOD, STATICMETHOD, FIELD, STATICFIELD, CALLBACK) \
     METHOD (constructor,   "<init>",        "(JLjava/lang/String;I)V") \
     METHOD (startWatching, "startWatching", "()V") \
     METHOD (stopWatching,  "stopWatching",  "()V") \
     CALLBACK (generatedCallback<&AndroidContentSharerFileObserver::onFileEventCallback>, "contentSharerFileObserverEvent", "(JILjava/lang/String;)V") \

    DECLARE_JNI_CLASS_WITH_BYTECODE (JuceContentProviderFileObserver, "com/rmsl/juce/JuceContentProviderFileObserver", 16, javaJuceContentProviderFileObserver)
    #undef JNI_CLASS_MEMBERS

    static void onFileEventCallback (JNIEnv*, AndroidContentSharerFileObserver& t, jint event, jstring path)
    {
        t.onFileEvent (event, LocalRef<jstring> (path));
    }
};

//==============================================================================
class ContentSharerGlobalImpl
{
public:
    static ContentSharerGlobalImpl& getInstance()
    {
        static ContentSharerGlobalImpl result;
        return result;
    }

    const String packageName = juceString (LocalRef<jstring> ((jstring) getEnv()->CallObjectMethod (getAppContext().get(),
                                                                                                    AndroidContext.getPackageName)));
    const String uriBase = "content://" + packageName + ".sharingcontentprovider/";

    std::unique_ptr<ActivityLauncher> sharePreparedFiles (const std::map<String, File>& fileForUriIn,
                                                          const StringArray& mimeTypes,
                                                          std::function<void (bool)> callback)
    {
        // This function should be called from the main thread, but must not race with singleton
        // access from other threads.
        const ScopedLock lock { mutex };

        if (! isContentSharingEnabled())
        {
            // You need to enable "Content Sharing" in Projucer's Android exporter.
            jassertfalse;
            NullCheckedInvocation::invoke (callback, false);
            return {};
        }

        auto* env = getEnv();

        fileForUri.insert (fileForUriIn.begin(), fileForUriIn.end());

        LocalRef<jobject> fileUris (env->NewObject (JavaArrayList, JavaArrayList.constructor, fileForUriIn.size()));

        for (const auto& pair : fileForUriIn)
        {
            env->CallBooleanMethod (fileUris,
                                    JavaArrayList.add,
                                    env->CallStaticObjectMethod (AndroidUri,
                                                                 AndroidUri.parse,
                                                                 javaString (pair.first).get()));
        }

        LocalRef<jobject> intent (env->NewObject (AndroidIntent, AndroidIntent.constructor));
        env->CallObjectMethod (intent,
                               AndroidIntent.setAction,
                               javaString ("android.intent.action.SEND_MULTIPLE").get());

        env->CallObjectMethod (intent,
                               AndroidIntent.setType,
                               javaString (getCommonMimeType (mimeTypes)).get());

        const auto permissions = [&]
        {
            constexpr int grantReadUriPermission   = 1;
            constexpr int grantPrefixUriPermission = 128;

            if (getAndroidSDKVersion() < 21)
                return grantReadUriPermission;

            return grantReadUriPermission | grantPrefixUriPermission;
        };

        env->CallObjectMethod (intent, AndroidIntent.setFlags, permissions);

        env->CallObjectMethod (intent,
                               AndroidIntent.putParcelableArrayListExtra,
                               javaString ("android.intent.extra.STREAM").get(),
                               fileUris.get());

        return doIntent (intent, callback);
    }

    std::unique_ptr<ActivityLauncher> shareText (const String& text,
                                                 std::function<void (bool)> callback)
    {
        // This function should be called from the main thread, but must not race with singleton
        // access from other threads.
        const ScopedLock lock { mutex };

        if (! isContentSharingEnabled())
        {
            // You need to enable "Content Sharing" in Projucer's Android exporter.
            jassertfalse;
            NullCheckedInvocation::invoke (callback, false);
            return {};
        }

        auto* env = getEnv();

        LocalRef<jobject> intent (env->NewObject (AndroidIntent, AndroidIntent.constructor));
        env->CallObjectMethod (intent,
                               AndroidIntent.setAction,
                               javaString ("android.intent.action.SEND").get());
        env->CallObjectMethod (intent,
                               AndroidIntent.putExtra,
                               javaString ("android.intent.extra.TEXT").get(),
                               javaString (text).get());
        env->CallObjectMethod (intent, AndroidIntent.setType, javaString ("text/plain").get());

        return doIntent (intent, callback);
    }

    static void onBroadcastResultReceive (JNIEnv*, jobject, int requestCode)
    {
        getInstance().sharingFinished (requestCode, true);
    }

    static jobject JNICALL contentSharerQuery (JNIEnv*, jobject contentProvider, jobject uri, jobjectArray projection)
    {
        return getInstance().query (LocalRef<jobject> (static_cast<jobject> (contentProvider)),
                                    LocalRef<jobject> (static_cast<jobject> (uri)),
                                    LocalRef<jobjectArray> (static_cast<jobjectArray> (projection)));
    }

    static jobject JNICALL contentSharerOpenFile (JNIEnv*, jobject contentProvider, jobject uri, jstring mode)
    {
        return getInstance().openFile (LocalRef<jobject> (static_cast<jobject> (contentProvider)),
                                       LocalRef<jobject> (static_cast<jobject> (uri)),
                                       LocalRef<jstring> (static_cast<jstring> (mode)));
    }

    static jobjectArray JNICALL contentSharerGetStreamTypes (JNIEnv*, jobject /*contentProvider*/, jobject uri, jstring mimeTypeFilter)
    {
        return getInstance().getStreamTypes (addLocalRefOwner (uri),
                                             addLocalRefOwner (mimeTypeFilter));
    }

private:
    ContentSharerGlobalImpl() = default;

    LocalRef<jobject> makeChooser (const LocalRef<jobject>& intent, int request) const
    {
        auto* env = getEnv();

        const auto text = javaString ("Choose share target");

        if (getAndroidSDKVersion() < 22)
            return LocalRef<jobject> (env->CallStaticObjectMethod (AndroidIntent,
                                                                   AndroidIntent.createChooser,
                                                                   intent.get(),
                                                                   text.get()));

        constexpr jint FLAG_UPDATE_CURRENT = 0x08000000;
        constexpr jint FLAG_IMMUTABLE = 0x04000000;

        const auto context = getAppContext();

        auto* klass = env->FindClass ("com/rmsl/juce/Receiver");
        const LocalRef<jobject> replyIntent (env->NewObject (AndroidIntent, AndroidIntent.constructorWithContextAndClass, context.get(), klass));
        getEnv()->CallObjectMethod (replyIntent, AndroidIntent.putExtraInt, javaString ("com.rmsl.juce.JUCE_REQUEST_CODE").get(), request);

        const auto flags = FLAG_UPDATE_CURRENT | (getAndroidSDKVersion() <= 23 ? 0 : FLAG_IMMUTABLE);
        const LocalRef<jobject> pendingIntent (env->CallStaticObjectMethod (AndroidPendingIntent,
                                                                            AndroidPendingIntent.getBroadcast,
                                                                            context.get(),
                                                                            request,
                                                                            replyIntent.get(),
                                                                            flags));

        return LocalRef<jobject> (env->CallStaticObjectMethod (AndroidIntent22,
                                                               AndroidIntent22.createChooser,
                                                               intent.get(),
                                                               text.get(),
                                                               env->CallObjectMethod (pendingIntent,
                                                                                      AndroidPendingIntent.getIntentSender)));
    }

    //==============================================================================
    jobject openFile (const LocalRef<jobject>& contentProvider,
                      const LocalRef<jobject>& uri,
                      [[maybe_unused]] const LocalRef<jstring>& mode)
    {
        // This function can be called from multiple threads.
        const ScopedLock lock { mutex };

        auto* env = getEnv();

        auto uriElements = getContentUriElements (env, uri);

        if (uriElements.file == File())
            return nullptr;

        return getAssetFileDescriptor (env, contentProvider, uriElements.file);
    }

    jobject query (const LocalRef<jobject>& contentProvider,
                   const LocalRef<jobject>& uri,
                   const LocalRef<jobjectArray>& projection)
    {
        // This function can be called from multiple threads.
        const ScopedLock lock { mutex };

        StringArray requestedColumns = javaStringArrayToJuce (projection);
        StringArray supportedColumns = getSupportedColumns();

        StringArray resultColumns;

        for (const auto& col : supportedColumns)
        {
            if (requestedColumns.contains (col))
                resultColumns.add (col);
        }

        // Unsupported columns were queried, file sharing may fail.
        if (resultColumns.isEmpty())
            return nullptr;

        auto resultJavaColumns = juceStringArrayToJava (resultColumns);

        auto* env = getEnv();

        const auto uriElements = getContentUriElements (env, uri);

        const auto callback = [info = uriElements.file] (auto& ref)
        {
            auto& pimplCursors = ContentSharerGlobalImpl::getInstance().cursors;
            const auto iter = std::lower_bound (pimplCursors.begin(), pimplCursors.end(), &ref, [] (const auto& managed, const auto* ptr)
            {
                return managed.get() == ptr;
            });

            if (iter != pimplCursors.end() && iter->get() == &ref)
                pimplCursors.erase (iter);
        };

        auto [iter, inserted] = cursors.emplace (new AndroidContentSharerCursor (env,
                                                                                 contentProvider,
                                                                                 resultJavaColumns,
                                                                                 callback));

        if (uriElements.file == File())
            return (*iter)->getNativeCursor();

        LocalRef<jobjectArray> values (env->NewObjectArray ((jsize) resultColumns.size(), JavaObject, nullptr));

        for (int i = 0; i < resultColumns.size(); ++i)
        {
            if (resultColumns.getReference (i) == "_display_name")
            {
                env->SetObjectArrayElement (values, i, javaString (uriElements.filename).get());
            }
            else if (resultColumns.getReference (i) == "_size")
            {
                LocalRef<jobject> javaFile (env->NewObject (JavaFile,
                                                            JavaFile.constructor,
                                                            javaString (uriElements.file.getFullPathName()).get()));

                jlong fileLength = env->CallLongMethod (javaFile, JavaFile.length);

                env->SetObjectArrayElement (values, i, env->NewObject (JavaLong, JavaLong.constructor, fileLength));
            }
        }

        (*iter)->addRow (values);
        return (*iter)->getNativeCursor();
    }

    jobjectArray getStreamTypes (const LocalRef<jobject>& uri, const LocalRef<jstring>& mimeTypeFilter)
    {
        // This function can be called from multiple threads.
        const ScopedLock lock { mutex };

        auto* env = getEnv();

        auto extension = getContentUriElements (env, uri).filename.fromLastOccurrenceOf (".", false, true);

        if (extension.isEmpty())
            return nullptr;

        return juceStringArrayToJava (filterMimeTypes (detail::MimeTypeTable::getMimeTypesForFileExtension (extension),
                                                       juceString (mimeTypeFilter.get()))).release();
    }

    std::unique_ptr<ActivityLauncher> doIntent (const LocalRef<jobject>& intent,
                                                std::function<void (bool)> callback)
    {
        static std::atomic<int> lastRequest = 1003;
        const auto requestCode = lastRequest++;
        callbackForRequest.emplace (requestCode, callback);
        const auto chooser = makeChooser (intent, requestCode);

        auto launcher = std::make_unique<ActivityLauncher> (chooser, requestCode);
        launcher->callback = [] (int request, int resultCode, LocalRef<jobject>)
        {
            ContentSharerGlobalImpl::getInstance().sharingFinished (request, resultCode == -1);
        };
        launcher->open();
        return launcher;
    }

    void sharingFinished (int request, bool succeeded)
    {
        // This function should be called from the main thread, but must not race with singleton
        // access from other threads.
        const ScopedLock lock { mutex };

        const auto iter = callbackForRequest.find (request);

        if (iter == callbackForRequest.end())
            return;

        const ScopeGuard scope { [&] { callbackForRequest.erase (iter); } };

        if (iter->second == nullptr)
            return;

        iter->second (succeeded);
    }

    bool isContentSharingEnabled() const
    {
        auto* env = getEnv();

        LocalRef<jobject> packageManager (env->CallObjectMethod (getAppContext().get(), AndroidContext.getPackageManager));

        constexpr int getProviders = 8;
        LocalRef<jobject> packageInfo (env->CallObjectMethod (packageManager,
                                                              AndroidPackageManager.getPackageInfo,
                                                              javaString (packageName).get(),
                                                              getProviders));
        LocalRef<jobjectArray> providers  ((jobjectArray) env->GetObjectField (packageInfo,
                                                                               AndroidPackageInfo.providers));

        if (providers == nullptr)
            return false;

        auto sharingContentProviderAuthority = packageName + ".sharingcontentprovider";
        const int numProviders = env->GetArrayLength (providers.get());

        for (int i = 0; i < numProviders; ++i)
        {
            LocalRef<jobject> providerInfo (env->GetObjectArrayElement (providers, i));
            LocalRef<jstring> authority ((jstring) env->GetObjectField (providerInfo, AndroidProviderInfo.authority));

            if (juceString (authority) == sharingContentProviderAuthority)
                return true;
        }

        return false;
    }

    //==============================================================================
    struct ContentUriElements
    {
        String filename;
        File file;
    };

    ContentUriElements getContentUriElements (JNIEnv* env, const LocalRef<jobject>& uri) const
    {
        const auto fullUri = juceString ((jstring) env->CallObjectMethod (uri.get(), AndroidUri.toString));

        const auto filename = fullUri.fromLastOccurrenceOf ("/", false, true);

        const auto iter = fileForUri.find (fullUri);
        const auto info = iter != fileForUri.end() ? iter->second : File{};

        return { filename, info };
    }

    static StringArray getSupportedColumns()
    {
        return StringArray ("_display_name", "_size");
    }

    jobject getAssetFileDescriptor (JNIEnv* env, const LocalRef<jobject>& contentProvider, const File& filepath)
    {
        if (nonAssetFilePathsPendingShare.find (filepath) == nonAssetFilePathsPendingShare.end())
        {
            const auto onCloseCallback = [filepath]
            {
                ContentSharerGlobalImpl::getInstance().nonAssetFilePathsPendingShare.erase (filepath);
            };

            auto observer = rawToUniquePtr (new AndroidContentSharerFileObserver (env,
                                                                                  contentProvider,
                                                                                  filepath,
                                                                                  onCloseCallback));

            nonAssetFilePathsPendingShare.emplace (filepath, std::move (observer));
        }

        const LocalRef<jobject> javaFile (env->NewObject (JavaFile,
                                                          JavaFile.constructor,
                                                          javaString (filepath.getFullPathName()).get()));

        constexpr int modeReadOnly = 268435456;
        LocalRef<jobject> parcelFileDescriptor (env->CallStaticObjectMethod (ParcelFileDescriptor,
                                                                             ParcelFileDescriptor.open,
                                                                             javaFile.get(),
                                                                             modeReadOnly));

        if (jniCheckHasExceptionOccurredAndClear())
        {
            // Failed to create file descriptor. Have you provided a valid file path/resource name?
            jassertfalse;
            return nullptr;
        }

        jlong startOffset = 0;
        jlong unknownLength = -1;

        assetFileDescriptors.add (GlobalRef (LocalRef<jobject> (env->NewObject (AssetFileDescriptor,
                                                                                AssetFileDescriptor.constructor,
                                                                                parcelFileDescriptor.get(),
                                                                                startOffset,
                                                                                unknownLength))));

        return assetFileDescriptors.getReference (assetFileDescriptors.size() - 1).get();
    }

    StringArray filterMimeTypes (const StringArray& mimeTypes, const String& filter)
    {
        String filterToUse (filter.removeCharacters ("*"));

        if (filterToUse.isEmpty() || filterToUse == "/")
            return mimeTypes;

        StringArray result;

        for (const auto& type : mimeTypes)
            if (String (type).contains (filterToUse))
                result.add (type);

        return result;
    }

    static String getCommonMimeType (const StringArray& mimeTypes)
    {
        if (mimeTypes.isEmpty())
            return "*/*";

        auto commonMime = mimeTypes[0];
        bool lookForCommonGroup = false;

        for (int i = 1; i < mimeTypes.size(); ++i)
        {
            if (mimeTypes[i] == commonMime)
                continue;

            if (! lookForCommonGroup)
            {
                lookForCommonGroup = true;
                commonMime = commonMime.upToFirstOccurrenceOf ("/", true, false);
            }

            if (! mimeTypes[i].startsWith (commonMime))
                return "*/*";
        }

        return lookForCommonGroup ? commonMime + "*" : commonMime;
    }

    CriticalSection mutex;
    Array<GlobalRef> assetFileDescriptors;
    std::map<File, std::unique_ptr<AndroidContentSharerFileObserver>> nonAssetFilePathsPendingShare;
    std::set<std::unique_ptr<AndroidContentSharerCursor>> cursors;
    std::map<String, File> fileForUri;
    std::map<int, std::function<void (bool)>> callbackForRequest;
};

#define JNI_CLASS_MEMBERS(METHOD, STATICMETHOD, FIELD, STATICFIELD, CALLBACK) \
     CALLBACK (ContentSharerGlobalImpl::contentSharerQuery,          "contentSharerQuery",          "(Landroid/net/Uri;[Ljava/lang/String;)Landroid/database/Cursor;") \
     CALLBACK (ContentSharerGlobalImpl::contentSharerOpenFile,       "contentSharerOpenFile",       "(Landroid/net/Uri;Ljava/lang/String;)Landroid/content/res/AssetFileDescriptor;") \
     CALLBACK (ContentSharerGlobalImpl::contentSharerGetStreamTypes, "contentSharerGetStreamTypes", "(Landroid/net/Uri;Ljava/lang/String;)[Ljava/lang/String;") \

DECLARE_JNI_CLASS (JuceSharingContentProvider, "com/rmsl/juce/JuceSharingContentProvider")
#undef JNI_CLASS_MEMBERS

#define JNI_CLASS_MEMBERS(METHOD, STATICMETHOD, FIELD, STATICFIELD, CALLBACK) \
     CALLBACK (ContentSharerGlobalImpl::onBroadcastResultReceive, "onBroadcastResultNative", "(I)V")

DECLARE_JNI_CLASS (AndroidReceiver, "com/rmsl/juce/Receiver")
#undef JNI_CLASS_MEMBERS

    //==============================================================================
class AndroidContentSharerPrepareFilesTask final : private AsyncUpdater
{
public:
    AndroidContentSharerPrepareFilesTask (const Array<URL>& fileUrls,
                                          std::function<void (const std::map<String, File>&, const StringArray&)> onCompletionIn)
        : onCompletion (std::move (onCompletionIn)),
          task (std::async (std::launch::async, [this, fileUrls]
          {
              run (fileUrls);
              triggerAsyncUpdate();
          })) {}

    ~AndroidContentSharerPrepareFilesTask() override
    {
        task.wait();
        cancelPendingUpdate();
    }

private:
    const String packageName = ContentSharerGlobalImpl::getInstance().packageName;
    const String uriBase     = ContentSharerGlobalImpl::getInstance().uriBase;

    struct StreamCloser
    {
        explicit StreamCloser (const LocalRef<jobject>& streamToUse)
            : stream (GlobalRef (streamToUse))
        {
        }

        ~StreamCloser()
        {
            if (stream.get() != nullptr)
                getEnv()->CallVoidMethod (stream, JavaCloseable.close);
        }

        GlobalRef stream;
    };

    void handleAsyncUpdate() override
    {
        onCompletion (infoForUri, mimeTypes);
    }

    void run (const Array<URL>& fileUrls)
    {
        auto* env = getEnv();

        StringArray filePaths;

        for (const auto& f : fileUrls)
        {
            const auto scheme = f.getScheme();

            // Only "file://" scheme or no scheme (for files in app bundle) are allowed!
            jassert (scheme.isEmpty() || scheme == "file");

            const auto fileToPrepare = [&]
            {
                if (! scheme.isEmpty())
                    return f;

                // Raw resource names need to be all lower case
                jassert (f.toString (true).toLowerCase() == f.toString (true));

                // This will get us a file with file:// URI
                return copyAssetFileToTemporaryFile (env, f.toString (true));
            }();

            if (fileToPrepare.isEmpty())
                continue;

            const auto filepath = URL::removeEscapeChars (fileToPrepare.toString (true).fromFirstOccurrenceOf ("file://", false, false));

            filePaths.add (filepath);
        }

        std::vector<String> extensions;

        for (const auto& filepath : filePaths)
        {
            const auto filename = filepath.fromLastOccurrenceOf ("/", false, true);
            extensions.push_back (filename.fromLastOccurrenceOf (".", false, true));
        }

        std::set<String> mimes;

        if (std::none_of (extensions.begin(), extensions.end(), [] (const String& s) { return s.isEmpty(); }))
            for (const auto& extension : extensions)
                for (const auto& mime : detail::MimeTypeTable::getMimeTypesForFileExtension (extension))
                    mimes.insert (mime);

        for (const auto& mime : mimes)
            mimeTypes.add (mime);

        for (auto it = filePaths.begin(); it != filePaths.end(); ++it)
        {
            const auto filename = it->fromLastOccurrenceOf ("/", false, true);
            const auto contentString = uriBase + String (std::distance (filePaths.begin(), it)) + "/" + filename;
            infoForUri.emplace (contentString, *it);
        }
    }

    URL copyAssetFileToTemporaryFile (JNIEnv* env, const String& filename)
    {
        LocalRef<jobject> resources (env->CallObjectMethod (getAppContext().get(), AndroidContext.getResources));
        int fileId = env->CallIntMethod (resources,
                                         AndroidResources.getIdentifier,
                                         javaString (filename).get(),
                                         javaString ("raw").get(),
                                         javaString (packageName).get());

        // Raw resource not found. Please make sure that you include your file as a raw resource
        // and that you specify just the file name, without an extension.
        jassert (fileId != 0);

        if (fileId == 0)
            return {};

        LocalRef<jobject> assetFd (env->CallObjectMethod (resources,
                                                          AndroidResources.openRawResourceFd,
                                                          fileId));

        StreamCloser inputStream (LocalRef<jobject> (env->CallObjectMethod (assetFd, AssetFileDescriptor.createInputStream)));

        if (jniCheckHasExceptionOccurredAndClear())
        {
            // Failed to open file stream for resource
            jassertfalse;
            return {};
        }

        auto tempFile = File::createTempFile ({});
        tempFile.createDirectory();
        tempFile = tempFile.getChildFile (filename);

        StreamCloser outputStream  (LocalRef<jobject> (env->NewObject (JavaFileOutputStream,
                                                                       JavaFileOutputStream.constructor,
                                                                       javaString (tempFile.getFullPathName()).get())));

        if (jniCheckHasExceptionOccurredAndClear())
        {
            // Failed to open file stream for temporary file
            jassertfalse;
            return {};
        }

        LocalRef<jbyteArray> buffer (env->NewByteArray (1024));
        int bytesRead = 0;

        for (;;)
        {
            bytesRead = env->CallIntMethod (inputStream.stream, JavaFileInputStream.read, buffer.get());

            if (jniCheckHasExceptionOccurredAndClear())
            {
                // Failed to read from resource file.
                jassertfalse;
                return {};
            }

            if (bytesRead < 0)
                break;

            env->CallVoidMethod (outputStream.stream, JavaFileOutputStream.write, buffer.get(), 0, bytesRead);

            if (jniCheckHasExceptionOccurredAndClear())
            {
                // Failed to write to temporary file.
                jassertfalse;
                return {};
            }
        }

        return URL (tempFile);
    }

    std::map<String, File> infoForUri;
    StringArray mimeTypes;
    std::function<void (const std::map<String, File>&, const StringArray&)> onCompletion;
    // This task is obtained from std::async(). Its destructor will block until the asynchronous
    // task has completed; as a result, we can guarantee that the async task will have finished
    // before the lifetimes of the other data members and base class end.
    std::future<void> task;
};

auto detail::ScopedContentSharerInterface::shareFiles (const Array<URL>& urls, Component*) -> std::unique_ptr<ScopedContentSharerInterface>
{
    class NativeScopedContentSharerInterface final : public detail::ScopedContentSharerInterface
    {
    public:
        explicit NativeScopedContentSharerInterface (Array<URL> f)
            : files (std::move (f)) {}

        void runAsync (ContentSharer::Callback callback) override
        {
            // This lambda will only be called if the AndroidContentSharerPrepareFilesTask is still
            // alive. We know that our lifetime will end after the
            // AndroidContentSharerPrepareFilesTask, so there's no need to check that 'this' is
            // still valid inside the lambda.
            task.emplace (files, [this, callback] (const std::map<String, File>& infoForUri, const StringArray& mimeTypes)
            {
                launcher = ContentSharerGlobalImpl::getInstance().sharePreparedFiles (infoForUri, mimeTypes, [callback] (bool success)
                {
                    callback (success, {});
                });
            });
        }

        void close() override
        {
            // dismiss() doesn't close the sharesheet, and there doesn't seem to be any alternative
            // Maybe this will work in the future...
            launcher.reset();
        }

    private:
        Array<URL> files;
        std::optional<AndroidContentSharerPrepareFilesTask> task;
        std::unique_ptr<ActivityLauncher> launcher;
    };

    return std::make_unique<NativeScopedContentSharerInterface> (std::move (urls));
}

auto detail::ScopedContentSharerInterface::shareText (const String& text, Component*) -> std::unique_ptr<ScopedContentSharerInterface>
{
    class NativeScopedContentSharerInterface final : public detail::ScopedContentSharerInterface
    {
    public:
        explicit NativeScopedContentSharerInterface (String t)
            : text (std::move (t)) {}

        void runAsync (ContentSharer::Callback callback) override
        {
            launcher = ContentSharerGlobalImpl::getInstance().shareText (text, [callback] (bool success)
            {
                callback (success, {});
            });
        }

        void close() override
        {
            // dismiss() doesn't close the sharesheet, and there doesn't seem to be any alternative
            // Maybe this will work in the future...
            launcher.reset();
        }

    private:
        String text;
        std::unique_ptr<ActivityLauncher> launcher;
    };

    return std::make_unique<NativeScopedContentSharerInterface> (std::move (text));
}

} // namespace juce