#ifndef _RIVE_STATE_MACHINE_INSTANCE_HPP_
#define _RIVE_STATE_MACHINE_INSTANCE_HPP_

#include <string>
#include <stddef.h>
#include <vector>
#include "rive/animation/linear_animation_instance.hpp"
#include "rive/listener_type.hpp"
#include "rive/scene.hpp"

namespace rive {
    class StateMachine;
    class LayerState;
    class SMIInput;
    class ArtboardInstance;
    class SMIBool;
    class SMINumber;
    class SMITrigger;
    class Shape;
    class StateMachineLayerInstance;
    class HitShape;
    class NestedArtboard;

    class StateMachineInstance : public Scene {
        friend class SMIInput;

    private:
        const StateMachine* m_Machine;
        bool m_NeedsAdvance = false;

        std::vector<SMIInput*> m_InputInstances; // we own each pointer
        size_t m_LayerCount;
        StateMachineLayerInstance* m_Layers;

        void markNeedsAdvance();

        std::vector<std::unique_ptr<HitShape>> m_HitShapes;
        std::vector<NestedArtboard*> m_HitNestedArtboards;

        /// Provide a hitListener if you want to process a down or an up for the pointer position
        /// too.
        void updateListeners(Vec2D position, ListenerType hitListener);

        template <typename SMType, typename InstType>
        InstType* getNamedInput(const std::string& name) const;

    public:
        StateMachineInstance(const StateMachine* machine, ArtboardInstance* instance);
        ~StateMachineInstance() override;

        // Advance the state machine by the specified time. Returns true if the
        // state machine will continue to animate after this advance.
        bool advance(float seconds);

        // Returns true when the StateMachineInstance has more data to process.
        bool needsAdvance() const;

        // Returns a pointer to the instance's stateMachine
        const StateMachine* stateMachine() const { return m_Machine; }

        size_t inputCount() const override { return m_InputInstances.size(); }
        SMIInput* input(size_t index) const override;
        SMIBool* getBool(const std::string& name) const override;
        SMINumber* getNumber(const std::string& name) const override;
        SMITrigger* getTrigger(const std::string& name) const override;

        const size_t currentAnimationCount() const;
        const LinearAnimationInstance* currentAnimationByIndex(size_t index) const;

        // The number of state changes that occurred across all layers on the
        // previous advance.
        size_t stateChangedCount() const;

        // Returns the state name for states that changed in layers on the
        // previously called advance. If the index of out of range, it returns
        // the empty string.
        const LayerState* stateChangedByIndex(size_t index) const;

        bool advanceAndApply(float secs) override;
        std::string name() const override;
        void pointerMove(Vec2D position) override;
        void pointerDown(Vec2D position) override;
        void pointerUp(Vec2D position) override;

        float durationSeconds() const override { return -1; }
        Loop loop() const override { return Loop::oneShot; }
        bool isTranslucent() const override { return true; }

        /// Allow anything referencing a concrete StateMachineInstace access to
        /// the backing artboard (explicitly not allowed on Scenes).
        Artboard* artboard() { return m_ArtboardInstance; }
    };
} // namespace rive
#endif