#pragma once

#include <Wire.h>
#include <ArduinoJson.h>

enum gesture_t : uint16_t {
    eGestureNone = 0x0000,
    eGestureRight = 0x0001,
    eGestureLeft = 0x0002,
    eGestureUp = 0x0004,
    eGestureDown = 0x0008,
    eGestureForward = 0x0010,
    eGestureBackward = 0x0020,
    eGestureClockwise = 0x0040,
    eGestureAntiClockwise = 0x0080,
    eGestureWave = 0x0100
};

struct GestureMsg {
    gesture_t gesture {eGestureNone};
    bool success {false};
    friend void toJson(JsonVariant v, GestureMsg const& a) {
        JsonArray arr = v.to<JsonArray>();
        arr.add(static_cast<uint16_t>(a.gesture));
        arr.add(a.success);
    }
    void fromJson(JsonVariantConst o) {
        JsonArrayConst arr = o.as<JsonArrayConst>();
        gesture = static_cast<gesture_t>(arr[0].as<uint16_t>());
        success = arr[1].as<bool>();
    }
};

class PAJ7620U2 {
  public:
    PAJ7620U2(TwoWire* w = &Wire, uint8_t addr = 0x73) : wire(w), dev(addr) {}
    int begin() {
        uint16_t id = 0;
        wire->begin();
        selectBank(0x00);
        if (readReg(REG_PART_ID, &id, 2) != 2) return ERR_BUS;
        if (id != PART_ID) return ERR_IC;
        for (size_t i = 0; i < (sizeof(initReg) / sizeof(initReg[0])); i++) writeReg(initReg[i][0], &initReg[i][1], 1);
        selectBank(0x00);
        return ERR_OK;
    }
    void setGestureHighRate(bool b) { highRate = b; }
    gesture_t getGesture() {
        uint8_t f1 = 0, f0 = 0, t0 = 0;
        if (readReg(REG_GES_FLAG_1, &f1, 1) != 1) return eGestureNone;
        if (f1) {
            vTaskDelay(highRate ? QUIT_MS / 5 : QUIT_MS / portTICK_PERIOD_MS);
            return eGestureWave;
        }
        if (readReg(REG_GES_FLAG_0, &f0, 1) != 1) return eGestureNone;
        if (!highRate) {
            vTaskDelay(ENTRY_MS / portTICK_PERIOD_MS);
            if (readReg(REG_GES_FLAG_0, &t0, 1) == 1) f0 |= t0;
        }
        if (f0 & 0x01) return eGestureRight;
        if (f0 & 0x02) return eGestureLeft;
        if (f0 & 0x04) return eGestureUp;
        if (f0 & 0x08) return eGestureDown;
        if (f0 & 0x10) return eGestureForward;
        if (f0 & 0x20) return eGestureBackward;
        if (f0 & 0x40) return eGestureClockwise;
        if (f0 & 0x80) return eGestureAntiClockwise;
        return eGestureNone;
    }

  private:
    static constexpr uint8_t REG_BANK_SEL = 0xEF;
    static constexpr uint8_t REG_GES_FLAG_0 = 0x43;
    static constexpr uint8_t REG_GES_FLAG_1 = 0x44;
    static constexpr uint8_t REG_PART_ID = 0x00;
    static constexpr uint16_t PART_ID = 0x7620;
    static constexpr uint16_t ENTRY_MS = 800;
    static constexpr uint16_t QUIT_MS = 1000;
    static constexpr int ERR_OK = 0;
    static constexpr int ERR_BUS = -1;
    static constexpr int ERR_IC = -2;

    void selectBank(uint8_t b) { writeReg(REG_BANK_SEL, &b, 1); }
    void writeReg(uint8_t reg, const void* p, size_t n) {
        if (!p || !n) return;
        const uint8_t* d = static_cast<const uint8_t*>(p);
        wire->beginTransmission(dev);
        wire->write(reg);
        for (size_t i = 0; i < n; i++) wire->write(d[i]);
        wire->endTransmission();
    }
    uint8_t readReg(uint8_t reg, void* p, size_t n) {
        if (!p || !n) return 0;
        uint8_t* d = static_cast<uint8_t*>(p);
        wire->beginTransmission(dev);
        wire->write(reg);
        if (wire->endTransmission(false) != 0) return 0;
        uint8_t r = wire->requestFrom(dev, static_cast<uint8_t>(n));
        for (uint8_t i = 0; i < r; i++) d[i] = wire->read();
        return r;
    }

    TwoWire* wire;
    uint8_t dev;
    bool highRate = false;

    static inline const uint8_t initReg[219][2] = {
        {0xEF, 0x00}, {0x32, 0x29}, {0x33, 0x01}, {0x34, 0x00}, {0x35, 0x01}, {0x36, 0x00}, {0x37, 0x07}, {0x38, 0x17},
        {0x39, 0x06}, {0x3A, 0x12}, {0x3F, 0x00}, {0x40, 0x02}, {0x41, 0xFF}, {0x42, 0x01}, {0x46, 0x2D}, {0x47, 0x0F},
        {0x48, 0x3C}, {0x49, 0x00}, {0x4A, 0x1E}, {0x4B, 0x00}, {0x4C, 0x20}, {0x4D, 0x00}, {0x4E, 0x1A}, {0x4F, 0x14},
        {0x50, 0x00}, {0x51, 0x10}, {0x52, 0x00}, {0x5C, 0x02}, {0x5D, 0x00}, {0x5E, 0x10}, {0x5F, 0x3F}, {0x60, 0x27},
        {0x61, 0x28}, {0x62, 0x00}, {0x63, 0x03}, {0x64, 0xF7}, {0x65, 0x03}, {0x66, 0xD9}, {0x67, 0x03}, {0x68, 0x01},
        {0x69, 0xC8}, {0x6A, 0x40}, {0x6D, 0x04}, {0x6E, 0x00}, {0x6F, 0x00}, {0x70, 0x80}, {0x71, 0x00}, {0x72, 0x00},
        {0x73, 0x00}, {0x74, 0xF0}, {0x75, 0x00}, {0x80, 0x42}, {0x81, 0x44}, {0x82, 0x04}, {0x83, 0x20}, {0x84, 0x20},
        {0x85, 0x00}, {0x86, 0x10}, {0x87, 0x00}, {0x88, 0x05}, {0x89, 0x18}, {0x8A, 0x10}, {0x8B, 0x01}, {0x8C, 0x37},
        {0x8D, 0x00}, {0x8E, 0xF0}, {0x8F, 0x81}, {0x90, 0x06}, {0x91, 0x06}, {0x92, 0x1E}, {0x93, 0x0D}, {0x94, 0x0A},
        {0x95, 0x0A}, {0x96, 0x0C}, {0x97, 0x05}, {0x98, 0x0A}, {0x99, 0x41}, {0x9A, 0x14}, {0x9B, 0x0A}, {0x9C, 0x3F},
        {0x9D, 0x33}, {0x9E, 0xAE}, {0x9F, 0xF9}, {0xA0, 0x48}, {0xA1, 0x13}, {0xA2, 0x10}, {0xA3, 0x08}, {0xA4, 0x30},
        {0xA5, 0x19}, {0xA6, 0x10}, {0xA7, 0x08}, {0xA8, 0x24}, {0xA9, 0x04}, {0xAA, 0x1E}, {0xAB, 0x1E}, {0xCC, 0x19},
        {0xCD, 0x0B}, {0xCE, 0x13}, {0xCF, 0x64}, {0xD0, 0x21}, {0xD1, 0x0F}, {0xD2, 0x88}, {0xE0, 0x01}, {0xE1, 0x04},
        {0xE2, 0x41}, {0xE3, 0xD6}, {0xE4, 0x00}, {0xE5, 0x0C}, {0xE6, 0x0A}, {0xE7, 0x00}, {0xE8, 0x00}, {0xE9, 0x00},
        {0xEE, 0x07}, {0xEF, 0x01}, {0x00, 0x1E}, {0x01, 0x1E}, {0x02, 0x0F}, {0x03, 0x10}, {0x04, 0x02}, {0x05, 0x00},
        {0x06, 0xB0}, {0x07, 0x04}, {0x08, 0x0D}, {0x09, 0x0E}, {0x0A, 0x9C}, {0x0B, 0x04}, {0x0C, 0x05}, {0x0D, 0x0F},
        {0x0E, 0x02}, {0x0F, 0x12}, {0x10, 0x02}, {0x11, 0x02}, {0x12, 0x00}, {0x13, 0x01}, {0x14, 0x05}, {0x15, 0x07},
        {0x16, 0x05}, {0x17, 0x07}, {0x18, 0x01}, {0x19, 0x04}, {0x1A, 0x05}, {0x1B, 0x0C}, {0x1C, 0x2A}, {0x1D, 0x01},
        {0x1E, 0x00}, {0x21, 0x00}, {0x22, 0x00}, {0x23, 0x00}, {0x25, 0x01}, {0x26, 0x00}, {0x27, 0x39}, {0x28, 0x7F},
        {0x29, 0x08}, {0x30, 0x03}, {0x31, 0x00}, {0x32, 0x1A}, {0x33, 0x1A}, {0x34, 0x07}, {0x35, 0x07}, {0x36, 0x01},
        {0x37, 0xFF}, {0x38, 0x36}, {0x39, 0x07}, {0x3A, 0x00}, {0x3E, 0xFF}, {0x3F, 0x00}, {0x40, 0x77}, {0x41, 0x40},
        {0x42, 0x00}, {0x43, 0x30}, {0x44, 0xA0}, {0x45, 0x5C}, {0x46, 0x00}, {0x47, 0x00}, {0x48, 0x58}, {0x4A, 0x1E},
        {0x4B, 0x1E}, {0x4C, 0x00}, {0x4D, 0x00}, {0x4E, 0xA0}, {0x4F, 0x80}, {0x50, 0x00}, {0x51, 0x00}, {0x52, 0x00},
        {0x53, 0x00}, {0x54, 0x00}, {0x57, 0x80}, {0x59, 0x10}, {0x5A, 0x08}, {0x5B, 0x94}, {0x5C, 0xE8}, {0x5D, 0x08},
        {0x5E, 0x3D}, {0x5F, 0x99}, {0x60, 0x45}, {0x61, 0x40}, {0x63, 0x2D}, {0x64, 0x02}, {0x65, 0x96}, {0x66, 0x00},
        {0x67, 0x97}, {0x68, 0x01}, {0x69, 0xCD}, {0x6A, 0x01}, {0x6B, 0xB0}, {0x6C, 0x04}, {0x6D, 0x2C}, {0x6E, 0x01},
        {0x6F, 0x32}, {0x71, 0x00}, {0x72, 0x01}, {0x73, 0x35}, {0x74, 0x00}, {0x75, 0x33}, {0x76, 0x31}, {0x77, 0x01},
        {0x7C, 0x84}, {0x7D, 0x03}, {0x7E, 0x01}};
};

class GestureSensor {
  public:
    GestureSensor() {}

    bool initialize() {
        msg.success = paj.begin() == 0;
        if (msg.success) paj.setGestureHighRate(true);
        return msg.success;
    }

    bool readGesture() {
        if (!msg.success) return false;
        const gesture_t g = paj.getGesture();
        if (g == eGestureNone) {
            msg.gesture = eGestureNone;
            return false;
        }
        if (g != msg.gesture) {
            msg.gesture = g;
            return true;
        }
        return false;
    }

    gesture_t getGesture() { return msg.gesture; }

    gesture_t takeGesture() {
        const auto g = msg.gesture;
        msg.gesture = eGestureNone;
        return g;
    }

    GestureMsg getGestureMsg() { return msg; }

    bool isActive() { return msg.success; }

  private:
    PAJ7620U2 paj;
    GestureMsg msg;
};