#pragma once

#include <stdint.h>

#include <avr/pgmspace.h>

#include "../clock.hpp"
#include "../io/io.hpp"

template <typename Spi, io::P RstPin, io::P DcPin, io::P BusyPin>
class Epd {
	static constexpr auto width = uint16_t{200};
	static constexpr auto height = uint16_t{200};

	struct Cmd {
		static constexpr auto SW_RESET = uint8_t{0x12};
		static constexpr auto DRIVER_OUTPUT_CONTROL = uint8_t{0x01};
		static constexpr auto DATA_ENTRY_MODE = uint8_t{0x11};
		static constexpr auto SET_RAM_X_ADDR_POSITIONS = uint8_t{0x44};
		static constexpr auto SET_RAM_Y_ADDR_POSITIONS = uint8_t{0x45};
		static constexpr auto BORDER_WAVEFORM_CONTROL = uint8_t{0x3C};
		static constexpr auto READ_TEMPERATURE_SENSOR = uint8_t{0x18};
		static constexpr auto SET_RAM_X_ADDR = uint8_t{0x4E};
		static constexpr auto SET_RAM_Y_ADDR = uint8_t{0x4F};
		static constexpr auto WRITE_RAM_BLACK = uint8_t{0x24};
		static constexpr auto WRITE_RAM_RED = uint8_t{0x26};
		static constexpr auto DISPLAY_UPDATE_CONTROL_2 = uint8_t{0x22};
		static constexpr auto UPDATE_DISPLAY = uint8_t{0x20};
		static constexpr auto DEEP_SLEEP_MODE = uint8_t{0x10};
	};

	io::Pin<RstPin> m_rst;
	io::Pin<DcPin> m_dc;
	io::Pin<BusyPin> m_bsy;

  public:
	Epd() = default;
	~Epd() = default;

	int Init()
	{
		m_rst.dir(io::Dir::OUT);
		m_dc.dir(io::Dir::OUT);
		m_bsy.dir(io::Dir::IN);
		Spi::init();

		Reset();

		WaitUntilIdle();
		SendCommand(Cmd::SW_RESET);
		WaitUntilIdle();

		SendCommand(Cmd::DRIVER_OUTPUT_CONTROL);
		SendData(0xC7);
		SendData(0x00);
		SendData(0x01);

		SendCommand(Cmd::DATA_ENTRY_MODE);
		SendData(0x01);

		SendCommand(Cmd::SET_RAM_X_ADDR_POSITIONS);
		SendData(0x00);
		SendData((width / 8) - 1);

		SendCommand(Cmd::SET_RAM_Y_ADDR_POSITIONS);
		SendData(height - 1);
		SendData(0x00);
		SendData(0x00);
		SendData(0x00);

		SendCommand(Cmd::BORDER_WAVEFORM_CONTROL);
		SendData(0x05);

		SendCommand(Cmd::READ_TEMPERATURE_SENSOR);
		SendData(0x80);

		SendCommand(Cmd::SET_RAM_X_ADDR);
		SendData(0x00);

		SendCommand(Cmd::SET_RAM_Y_ADDR);
		SendData(height - 1);
		SendData(0x00);

		WaitUntilIdle();

		return 0;
	}

	void SendCommand(unsigned char command)
	{
		m_dc = false;
		SpiTransfer(command);
	}

	void SendData(unsigned char data)
	{
		m_dc = true;
		SpiTransfer(data);
	}

	void WaitUntilIdle()
	{
		while (m_bsy) {
			_delay_ms(100);
		}
	}

	void Reset()
	{
		m_rst = true;
		_delay_ms(200);
		m_rst = false; // module reset
		_delay_ms(10);
		m_rst = true;
		_delay_ms(200);
	}

	void DisplayFrame(const unsigned char *frame_buffer_black, const unsigned char *frame_buffer_red)
	{
		SendCommand(Cmd::WRITE_RAM_BLACK);
		for (auto i = uint16_t{0}; i < width * height / 8; i++) {
			SendData(pgm_read_byte(&frame_buffer_black[i]));
		}
		SendCommand(Cmd::WRITE_RAM_RED);
		for (auto i = uint16_t{0}; i < width * height / 8; i++) {
			SendData(~pgm_read_byte(&frame_buffer_red[i]));
		}

		SendCommand(Cmd::DISPLAY_UPDATE_CONTROL_2);
		SendData(0xF7);
		SendCommand(Cmd::UPDATE_DISPLAY);
		WaitUntilIdle();
	}

	void DisplayClear()
	{
		SendCommand(Cmd::WRITE_RAM_BLACK);
		for (auto i = uint16_t{0}; i < width * height / 8; i++) {
			SendData(0xff);
		}
		SendCommand(Cmd::WRITE_RAM_RED);
		for (auto i = uint16_t{0}; i < width * height / 8; i++) {
			SendData(0x00);
		}

		SendCommand(Cmd::DISPLAY_UPDATE_CONTROL_2);
		SendData(0xF7);
		SendCommand(Cmd::UPDATE_DISPLAY);
		WaitUntilIdle();
	}

	void Sleep()
	{
		SendCommand(Cmd::DEEP_SLEEP_MODE);
		SendData(0x01);
		_delay_ms(100);
	}

	void SpiTransfer(unsigned char data)
	{
		Spi::select(true);
		Spi::transfer(data);
		Spi::select(false);
	}
};