eink/eink.hpp

#pragma once

#include <tuple>
#include <type_traits>
#include <utility>

#include <cstddef>
#include <cstdint>

#include <avr/pgmspace.h>

#include "eink_spi.hpp"

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

namespace eink {

template <std::uint16_t Width, std::uint16_t Height, typename Spi, io::P RstPin, io::P BusyPin>
class Eink {
	using word_t = typename Spi::word_t;

	static io::Pin<RstPin> m_rst;
	static io::Pin<BusyPin> m_busy;

	template <typename T>
	static T pgm_load(const T &object)
	{
		auto buffer = T{};
		auto rawBuffer = reinterpret_cast<std::byte *>(&buffer);
		for (auto i = std::size_t{0}; i < sizeof(T); ++i) {
			rawBuffer[i] = static_cast<std::byte>(pgm_read_byte(&reinterpret_cast<const std::byte *>(&object)[i]));
		}
		return buffer;
	}

  public:
	enum class Cmd : std::uint8_t {
		DRIVER_OUTPUT_CONTROL = 0x01,
		DEEP_SLEEP_MODE = 0x10,
		DATA_ENTRY_MODE = 0x11,
		SW_RESET = 0x12,
		READ_TEMPERATURE_SENSOR = 0x18,
		UPDATE_DISPLAY = 0x20,
		DISPLAY_UPDATE_CONTROL_2 = 0x22,
		WRITE_RAM_BLACK = 0x24,
		WRITE_RAM_RED = 0x26,
		BORDER_WAVEFORM_CONTROL = 0x3C,
		SET_RAM_X_ADDR_POSITIONS = 0x44,
		SET_RAM_Y_ADDR_POSITIONS = 0x45,
		SET_RAM_X_ADDR = 0x4E,
		SET_RAM_Y_ADDR = 0x4F,
	};

	enum class Color : std::uint8_t {
		BLACK,
		WHITE,
		RED,
	};

	enum class RamDirection : std::uint8_t {
		DECREMENT = 0,
		INCREMENT = 1,
	};

	enum class FastestMovingIndex : std::uint8_t {
		X = 0,
		Y = 1,
	};

	static void init()
	{
		m_rst.dir(io::Dir::OUT);
		m_busy.pullup(false);
		m_busy.dir(io::Dir::IN);
		Spi::init();

		reset();
		softReset();

		sendCommand(Cmd::DRIVER_OUTPUT_CONTROL);
		sendData(0xC7);
		sendData(0x00);
		sendData(0x01);

		setDataEntryMode(RamDirection::DECREMENT, RamDirection::INCREMENT, FastestMovingIndex::X);

		setRamRange({Width / 8 - 1, 0}, {0, Height - 1});

		sendCommand(Cmd::BORDER_WAVEFORM_CONTROL);
		sendData(0x05);

		sendCommand(Cmd::READ_TEMPERATURE_SENSOR);
		sendData(0x80);

		setRamXPos(Width / 8 - 1);
		setRamYPos(0);

		waitUntilIdle();
	}

	static void sendCommand(const Cmd command)
	{
		Spi::select(true);
		Spi::write(static_cast<word_t>(command), true);
		Spi::select(false);
	}

	static void sendData(word_t data)
	{
		Spi::select(true);
		Spi::write(data, false);
		Spi::select(false);
	}

	static word_t readData()
	{
		Spi::select(true);
		const auto res = Spi::read();
		Spi::select(false);
		return res;
	}

	static void waitUntilIdle()
	{
		while (m_busy) {
			_delay_ms(100);
		}
	}

	static void reset()
	{
		m_rst = true;
		_delay_ms(200);
		m_rst = false;
		_delay_ms(10);
		m_rst = true;
		_delay_ms(200);
		waitUntilIdle();
	}

	static void softReset()
	{
		sendCommand(Cmd::SW_RESET);
		waitUntilIdle();
	}

	template <typename RleImage>
	static void draw(const RleImage &rleImage)
	{
		constexpr auto sendImageChannel = [](const auto command, const auto &image) {
			sendCommand(command);
			for (auto j = std::size_t{0}; j < image.size(); ++j) {
				const auto [count, data] = pgm_load(image[j]);
				for (auto i = std::uint16_t{0}; i < count; ++i) {
					if (command == Cmd::WRITE_RAM_BLACK) {
						sendData(data);
					} else {
						sendData(~data);
					}
				}
			}
		};

		sendImageChannel(Cmd::WRITE_RAM_BLACK, std::get<0>(rleImage));
		sendImageChannel(Cmd::WRITE_RAM_RED, std::get<1>(rleImage));

		sendCommand(Cmd::DISPLAY_UPDATE_CONTROL_2);
		sendData(0xF7);
		sendCommand(Cmd::UPDATE_DISPLAY);
		waitUntilIdle();
	}

	static void clear(const Color color = Color::WHITE)
	{
		constexpr auto getFillData = [](const auto &color) -> std::pair<std::uint8_t, std::uint8_t> {
			switch (color) {
			case Color::WHITE:
				return {0xFF, 0x00};
			case Color::BLACK:
				return {0x00, 0x00};
			case Color::RED:
				return {0xFF, 0xFF};
			}
			return {0xFF, 0x00};
		};

		const auto fillData = getFillData(color);

		sendCommand(Cmd::WRITE_RAM_BLACK);
		for (auto i = std::uint16_t{0}; i < Width * Height / 8; i++) {
			sendData(fillData.first);
		}
		sendCommand(Cmd::WRITE_RAM_RED);
		for (auto i = std::uint16_t{0}; i < Width * Height / 8; i++) {
			sendData(fillData.second);
		}

		sendCommand(Cmd::DISPLAY_UPDATE_CONTROL_2);
		sendData(0xF7);
		sendCommand(Cmd::UPDATE_DISPLAY);
		waitUntilIdle();
	}

	static void autoPatternFill()
	{
		constexpr auto RED_PATTERN_FILL_CMD = static_cast<Cmd>(0x46);
		constexpr auto BLACK_PATTERN_FILL_CMD = static_cast<Cmd>(0x47);

		constexpr auto RED_PATTERN = 0b0'001'0'001;
		constexpr auto BLACK_PATTERN = 0b1'000'0'000;

		sendCommand(RED_PATTERN_FILL_CMD);
		sendData(RED_PATTERN);
		waitUntilIdle();

		sendCommand(BLACK_PATTERN_FILL_CMD);
		sendData(BLACK_PATTERN);
		waitUntilIdle();

		sendCommand(Cmd::DISPLAY_UPDATE_CONTROL_2);
		sendData(0xF7);
		sendCommand(Cmd::UPDATE_DISPLAY);
		waitUntilIdle();
	}

	static void setDataEntryMode(const RamDirection &xDir = RamDirection::INCREMENT,
	                             const RamDirection &yDir = RamDirection::INCREMENT,
	                             const FastestMovingIndex &fastestMovingIndex = FastestMovingIndex::X)
	{
		auto setting = static_cast<std::uint8_t>(xDir) << 0;
		setting |= static_cast<std::uint8_t>(yDir) << 1;
		setting |= static_cast<std::uint8_t>(fastestMovingIndex) << 2;

		sendCommand(Cmd::DATA_ENTRY_MODE);
		sendData(setting);
	}

	static void setRamRange(const std::pair<std::uint8_t, std::uint8_t> &xrange,
	                        const std::pair<std::uint16_t, std::uint16_t> &yrange)
	{
		sendCommand(Cmd::SET_RAM_X_ADDR_POSITIONS);
		sendData(xrange.first & 0b00111111);
		sendData(xrange.second & 0b00111111);

		sendCommand(Cmd::SET_RAM_Y_ADDR_POSITIONS);
		sendData(yrange.first & 0xFF);
		sendData((yrange.first >> 8) & 0b1);
		sendData(yrange.second & 0xFF);
		sendData((yrange.second >> 8) & 0b1);
	}

	static void setRamXPos(const std::uint8_t pos)
	{
		sendCommand(Cmd::SET_RAM_X_ADDR);
		sendData(pos & 0b00111111);
	}

	static void setRamYPos(const std::uint16_t pos)
	{
		sendCommand(Cmd::SET_RAM_Y_ADDR);
		sendData(pos & 0xFF);
		sendData((pos >> 8) & 0b1);
	}

	static void sleep()
	{
		sendCommand(Cmd::DEEP_SLEEP_MODE);
		sendData(0x01);
		_delay_ms(100);
	}
};

} // namespace eink