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//////////////////////////////////////////////////////////////////////////////

#pragma once

#include <musikcore/config.h>
#include <musikcore/audio/ITransport.h>
#include <musikcore/audio/Player.h>
#include <musikcore/audio/Crossfader.h>
#include <musikcore/runtime/MessageQueue.h>
#include <musikcore/sdk/IOutput.h>
#include <musikcore/sdk/constants.h>

#include <thread>
#include <mutex>

#include <sigslot/sigslot.h>

namespace musik { namespace core { namespace audio {

    class CrossfadeTransport :
        public ITransport,
        private Player::EventListener,
        public sigslot::has_slots<>
    {
        public:
            CrossfadeTransport();
            virtual ~CrossfadeTransport();

            void StopImmediately();

            void Start(const std::string& uri, Gain gain, StartMode mode) override;
            void PrepareNextTrack(const std::string& uri, Gain gain) override;

            std::string Uri() override;

            void Stop() override;
            bool Pause() override;
            bool Resume() override;

            double Position() override;
            void SetPosition(double seconds) override;

            double Volume() noexcept override;
            void SetVolume(double volume) override;

            bool IsMuted() noexcept override;
            void SetMuted(bool muted) override;

            double GetDuration() override;

            void ReloadOutput() override;

            musik::core::sdk::PlaybackState GetPlaybackState() override;
            musik::core::sdk::StreamState GetStreamState() override;

        private:
            using Lock = std::unique_lock<std::recursive_mutex>;
            using Output = std::shared_ptr<musik::core::sdk::IOutput>;
            using Thread = std::shared_ptr<std::thread>;
            using IMessage = musik::core::runtime::IMessage;
            using IMessageTarget = musik::core::runtime::IMessageTarget;
            using MessageQueue = musik::core::runtime::MessageQueue;

            struct PlayerContext {
                PlayerContext(
                    CrossfadeTransport& transport,
                    Crossfader& crossfader) noexcept;

                void Reset();

                void Reset(
                    const std::string& url,
                    Player::EventListener* listener,
                    Gain gain,
                    bool startImmediate);

                void TransferTo(PlayerContext& context) noexcept;

                void Start(double transportVolume);
                void Stop();
                void StopIf(Player const* player);
                void Pause();
                void Resume(double transportVolume);
                void SetVolume(double volume);
                bool IsEmpty() noexcept;

                bool startImmediate;
                bool started;
                bool canFade;
                Output output;
                Player *player;
                CrossfadeTransport& transport;
                Crossfader& crossfader;
            };

            void RaiseStreamEvent(musik::core::sdk::StreamState type, Player const* player);
            void SetPlaybackState(musik::core::sdk::PlaybackState state);

            void OnCrossfaderEmptied();

            void OnPlayerBuffered(Player* player) override;
            void OnPlayerStarted(Player* player) override;
            void OnPlayerFinished(Player* player) override;
            void OnPlayerOpenFailed(Player* player) override;
            void OnPlayerMixPoint(Player* player, int id, double time) override;
            void OnPlayerDestroying(Player* player) override;

            musik::core::sdk::PlaybackState playbackState;
            musik::core::sdk::StreamState activePlayerState;
            std::recursive_mutex stateMutex;
            Crossfader crossfader;
            PlayerContext active;
            PlayerContext next;
            double volume;
            bool muted;
    };

} } }
