#ifndef AY8910_HH

#define AY8910_HH

#include "ResampledSoundDevice.hh"

#include "FloatSetting.hh"

#include "SimpleDebuggable.hh"

#include "TclCallback.hh"

#include <array>

#include <cstdint>

namespace openmsx {

class AY8910Periphery;

class DeviceConfig;

/** This class implements the AY-3-8910 sound chip.

  * Only the AY-3-8910 is emulated, no surrounding hardware,

  * use the class AY8910Periphery to connect peripherals.

  */

class AY8910 final : public ResampledSoundDevice

{

public:

	AY8910(const std::string& name, AY8910Periphery& periphery,

	       const DeviceConfig& config, EmuTime time);

	~AY8910();

	[[nodiscard]] uint8_t readRegister(unsigned reg, EmuTime time);

	[[nodiscard]] uint8_t peekRegister(unsigned reg, EmuTime time) const;

	void writeRegister(unsigned reg, uint8_t value, EmuTime time);

	void reset(EmuTime time);

	template<typename Archive>

	void serialize(Archive& ar, unsigned version);

private:

	class Generator {

	public:

		void setPeriod(int value);

		[[nodiscard]] unsigned getNextEventTime() const;

		void advanceFast(unsigned duration);

		template<typename Archive>

		void serialize(Archive& ar, unsigned version);

	protected:

		Generator() = default;

		void reset();

		/** Time between output steps.

		  * For tones, this is half the period of the square wave.

		  * For noise, this is the time before the random generator produces

		  * its next output.

		  */

		int period;

		/** Time passed in this period.

		  * Usually count will be smaller than period, but when the period

		  * was recently changed this might not be the case.

		  */

		int count;

	};

	class ToneGenerator : public Generator {

	public:

		ToneGenerator();

		void reset();

		/** Advance tone generator several steps in time.

		  * @param duration Length of interval to simulate.

		  */

		void advance(unsigned duration);

		void doNextEvent(const AY8910& ay8910);

		/** Gets the current output of this generator.

		  */

		[[nodiscard]] bool getOutput() const { return output; }

		template<typename Archive>

		void serialize(Archive& ar, unsigned version);

	private:

		[[nodiscard]] int getDetune(const AY8910& ay8910);

	private:

		/** Time passed since start of vibrato cycle.

		  */

		unsigned vibratoCount = 0;

		unsigned detuneCount = 0;

		/** Current state of the wave.

		  */

		bool output;

	};

	class NoiseGenerator : public Generator {

	public:

		NoiseGenerator();

		void reset();

		/** Advance noise generator several steps in time.

		  * @param duration Length of interval to simulate.

		  */

		void advance(unsigned duration);

		void doNextEvent();

		/** Gets the current output of this generator.

		  */

		[[nodiscard]] bool getOutput() const { return random & 1; }

		template<typename Archive>

		void serialize(Archive& ar, unsigned version);

	private:

		int random;

	};

	class Amplitude {

	public:

		explicit Amplitude(const DeviceConfig& config);

		[[nodiscard]] auto getEnvVolTable() const { return envVolTable; }

		[[nodiscard]] float getVolume(unsigned chan) const;

		void setChannelVolume(unsigned chan, unsigned value);

		[[nodiscard]] bool followsEnvelope(unsigned chan) const;

	private:

		const bool isAY8910; // must come before envVolTable

		std::span<const float, 32> envVolTable;

		std::array<float, 3> vol;

		std::array<bool, 3> envChan;

	};

	class Envelope {

	public:

		explicit Envelope(std::span<const float, 32> envVolTable);

		void reset();

		void setPeriod(int value);

		void setShape(unsigned shape);

		[[nodiscard]] bool isChanging() const;

		void advance(unsigned duration);

		[[nodiscard]] float getVolume() const;

		[[nodiscard]] unsigned getNextEventTime() const;

		void advanceFast(unsigned duration);

		void doNextEvent();

		template<typename Archive>

		void serialize(Archive& ar, unsigned version);

	private:

		void doSteps(int steps);

	private:

		std::span<const float, 32> envVolTable;

		int period = 1;

		int count = 0;

		int step = 0;

		int attack = 0;

		bool hold = false, alternate = false, holding = false;

	};

	// SoundDevice

	void generateChannels(std::span<float*> bufs, unsigned num) override;

	[[nodiscard]] float getAmplificationFactorImpl() const override;

	// Observer<Setting>

	void update(const Setting& setting) noexcept override;

	void wrtReg(unsigned reg, uint8_t value, EmuTime time);

private:

	AY8910Periphery& periphery;

	struct Debuggable final : SimpleDebuggable {

		Debuggable(MSXMotherBoard& motherBoard, const std::string& name);

		[[nodiscard]] uint8_t read(unsigned address, EmuTime time) override;

		void write(unsigned address, uint8_t value, EmuTime time) override;

	} debuggable;

	FloatSetting vibratoPercent;

	FloatSetting vibratoFrequency;

	FloatSetting detunePercent;

	FloatSetting detuneFrequency;

	TclCallback directionsCallback;

	std::array<ToneGenerator, 3> tone;

	NoiseGenerator noise;

	Amplitude amplitude;

	Envelope envelope;

	std::array<uint8_t, 16> regs;

	const bool isAY8910;

	const bool ignorePortDirections;

	bool doDetune;

};

SERIALIZE_CLASS_VERSION(AY8910::Generator, 2);

SERIALIZE_CLASS_VERSION(AY8910::ToneGenerator, 2);

SERIALIZE_CLASS_VERSION(AY8910::NoiseGenerator, 2);

} // namespace openmsx

#endif // AY8910_HH