/**************************************************************************

  https://grok.com/share/bGVnYWN5_606fe78d-439e-484c-b71a-41b17f2d3894

  https://grok.com/share/bGVnYWN5_29159ac2-7dbd-481c-9d6a-2e33a0160839

  https://grok.com/share/bGVnYWN5_1ab675dc-2f2a-4bb8-bced-cd9b7e89ef90


 **************************************************************************/


/*
  Wireless Bucket Level Project
  ESP32-S2 Mini + 1.69" ST7789V3 (240x280) TFT
  Optimized Hardware SPI + Your Custom Pins
*/

//define debug
//#define ST7789
#define F //  fahrenheit temperature

#include <Adafruit_NeoPixel.h>
#include <WiFi.h>
#include <AsyncTCP.h>
#include <ESPAsyncWebServer.h>
#include <Adafruit_MPU6050.h>
#include <Adafruit_Sensor.h>
#include <Arduino_JSON.h>
#include <OneButton.h>
#ifdef ST7789
#include <Adafruit_ST7789.h>
#else
#include <Adafruit_ILI9341.h>
#endif
#include <SPI.h>
#include "page.h"

// Preprocessor fix for JavaScript in raw literal
#define function

// ====================== YOUR CUSTOM PIN DEFINITIONS ======================
#define TFT_CS      5//
#define TFT_RST     4//
#define TFT_DC      2//
#define TFT_CLK     7//     // SCLK
#define TFT_MOSI    11//    // MOSI
#define TFT_MISO    9//     // MISO (not always needed for display)
#define TFT_LED     6//     // Backlight

#define SDA_pin     33//
#define SCL_pin     35//

#define batteryVoltagePin  1//
#define PIXEL_PIN         16
#define onboard_LED_pin   15  //  ESP32-S2 Mini onboard LED =15
// Buttons
#define upButtonPin       18
#define downButtonPin     17
#define enterButtonPin    21   // if needed later

// ====================== CONSTANTS ======================
#define batteryVoltageHigh  4.2
#define batteryVoltageNom   3.7
#define batteryVoltageLow   3.2

#define NUMPIXELS           1

const char* ssid = "Wokwi-GUEST";
const char* password = "";

const char* compileDateTime = __DATE__ " " __TIME__;

const float G = 9.80665;

// ====================== OBJECTS ======================
// Hardware SPI TFT
#ifdef ST7789
Adafruit_ST7789 tft = Adafruit_ST7789(TFT_CS, TFT_DC, TFT_RST);
#else
Adafruit_ILI9341 tft = Adafruit_ILI9341(TFT_CS, TFT_DC, TFT_RST);
#endif

Adafruit_MPU6050 mpu;
Adafruit_NeoPixel pixels(NUMPIXELS, PIXEL_PIN, NEO_GRB + NEO_KHZ800);

OneButton button1(upButtonPin, true);
OneButton button2(downButtonPin, true);
//OneButton button3(enterButtonPin, true);  // if needed later

AsyncWebServer server(80);
AsyncEventSource events("/events");

JSONVar readings;

sensors_event_t a, g, temp;

struct GyroData {
  float pitch = 0;
  float roll = 0;
  float yaw = 0;
  float prev_pitch = 0;
  float prev_roll = 0;
  float prev_yaw = 0;
}; // <-- Don't forget this semicolon!

// 2. Create an instance of the struct
GyroData gyroData;

// ====================== VARIABLES ======================
unsigned long lastTime = 0, lastTimeTemperature = 0, lastTimeAcc = 0, lastTimeVoltage = 0;
unsigned long gyroDelay = 20, temperatureDelay = 1000, accelerometerDelay = 200, voltageDelay = 2000;

float gyroX = 0, gyroY = 0, gyroZ = 0;
float prevGyroX = 0, prevGyroY = 0, prevGyroZ = 0;
float accX, accY, accZ;
float temperature = 0;
float batteryVoltage = 0;
float prevbatteryVoltage = 0;
unsigned long previousTime = 0;



// ====================== SETUP ======================
void setup() {
#ifdef debug
  Serial.begin(115200);
  Serial.println("ESP32-S2 Mini + ST7789 TFT Ready");
#endif
  analogReadResolution(13);


  // Pin configuration
  pinMode(TFT_LED, OUTPUT);
  digitalWrite(TFT_LED, HIGH);

  pinMode(upButtonPin, INPUT_PULLUP);
  pinMode(downButtonPin, INPUT_PULLUP);

  setup_buttons();

  // Initialize TFT with Hardware SPI
  setup_display();
  boot_display();

  pixels.begin();
  pixels.clear();
  pixels.show();

  initWiFi();
  initMPU();
  previousTime = millis();

  // Web Server
  server.on("/", HTTP_GET, [](AsyncWebServerRequest * request) {
    request->send_P(200, "text/html", index_html);
  });

  server.on("/reset", HTTP_GET, [](AsyncWebServerRequest * request) {
    prevGyroX += gyroX; prevGyroY += gyroY; prevGyroZ += gyroZ;
    gyroX = gyroY = gyroZ = 0;
    request->send(200, "text/plain", "OK");
  });
  server.on("/resetX", HTTP_GET, [](AsyncWebServerRequest * request) {
    prevGyroX += gyroX;
    gyroX = 0;
    request->send(200, "text/plain", "OK");
  });
  server.on("/resetY", HTTP_GET, [](AsyncWebServerRequest * request) {
    prevGyroY += gyroY;
    gyroY = 0;
    request->send(200, "text/plain", "OK");
  });
  server.on("/resetZ", HTTP_GET, [](AsyncWebServerRequest * request) {
    prevGyroZ += gyroZ;
    gyroZ = 0;
    request->send(200, "text/plain", "OK");
  });

  events.onConnect([](AsyncEventSourceClient * client) {
    client->send("hello!", NULL, millis(), 10000);
  });
  server.addHandler(&events);
  server.begin();

#ifdef debug
  Serial.println("System Ready - Hardware SPI @ 40MHz");
#endif

  main_display_static();

}

// ====================== MAIN LOOP ======================
void loop() {
  button1.tick();
  button2.tick();


  if ((millis() - lastTime) > gyroDelay) {
    events.send(getGyroReadings().c_str(), "gyro_readings", millis());
    lastTime = millis();
  }
  if ((millis() - lastTimeAcc) > accelerometerDelay) {
    events.send(getAccReadings().c_str(), "accelerometer_readings", millis());
    lastTimeAcc = millis();
  }
  if ((millis() - lastTimeTemperature) > temperatureDelay) {
    events.send(getTemperature().c_str(), "temperature_reading", millis());
    lastTimeTemperature = millis();
  }
  if ((millis() - lastTimeVoltage) > voltageDelay) {
    events.send(getVoltage().c_str(), "voltage_reading", millis());
    lastTimeVoltage = millis();
  }
  if (gyroData.pitch  != gyroData.prev_pitch ||
      gyroData.roll  != gyroData.prev_roll ||
      gyroData.yaw  != gyroData.prev_yaw) {

    main_display();

    gyroData.prev_pitch  = gyroData.pitch;
    gyroData.prev_roll  = gyroData.roll;
    gyroData.prev_yaw  = gyroData.yaw;
  }
}

// ====================== FUNCTIONS ======================

void initMPU() {
  Wire.begin(SDA_pin, SCL_pin);
  if (!mpu.begin()) {
#ifdef debug
    Serial.println("MPU6050 Failed!");
#endif
    while (1) delay(100);
  }
#ifdef debug
  Serial.println("MPU6050 OK");
#endif
  mpu.setGyroRange(MPU6050_RANGE_250_DEG);
  mpu.setFilterBandwidth(MPU6050_BAND_44_HZ);
}
//--------------------------------------------------------
void initWiFi() {
  WiFi.mode(WIFI_STA);
  WiFi.begin(ssid, password);
  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
#ifdef debug
    Serial.print(".");
#endif
  }
#ifdef debug
  Serial.println("\nWiFi Connected - IP: " + WiFi.localIP().toString());
#endif
}
//--------------------------------------------------------
String getGyroReadings() {
  mpu.getEvent(&a, &g, &temp);
  unsigned long currentTime = millis();
  float dt = (currentTime - previousTime) / 1000.0;
  previousTime = currentTime;

  gyroX += (g.gyro.x * 180.0 / PI) * dt;
  gyroY += (g.gyro.y * 180.0 / PI) * dt;
  gyroZ += (g.gyro.z * 180.0 / PI) * dt;

  gyroData.pitch = gyroX;
  gyroData.roll = gyroY;
  gyroData.yaw = gyroZ;

  readings["pitch"] = String(gyroX, 1);
  readings["roll"]  = String(gyroY, 1);
  readings["yaw"]   = String(gyroZ, 1);
  return JSON.stringify(readings);
}
//--------------------------------------------------------
String getAccReadings() {
  mpu.getEvent(&a, &g, &temp);
  readings["accX"] = String(a.acceleration.x, 2);
  readings["accY"] = String(a.acceleration.y, 2);
  readings["accZ"] = String(a.acceleration.z, 2);
  return JSON.stringify(readings);
}
//--------------------------------------------------------
String getTemperature() {
  mpu.getEvent(&a, &g, &temp);
#ifdef F
  float temp_f = (temp.temperature * 9.0 / 5.0) + 32.0;
  return String(temp_f, 1);
#else
  return String(temp.temperature, 1);
#endif
}
//--------------------------------------------------------
String getVoltage() {
  //int raw = analogReadMilliVolts(batteryVoltagePin);
  int raw = analogRead(batteryVoltagePin);
#ifdef debug
  Serial.print("analog:\t"); Serial.println(raw);
#endif
  batteryVoltage = mapf(raw, 0, 8191, 0.0, 5.0);
  return String(batteryVoltage, 2);
}
//--------------------------------------------------------
float mapf(float x, float in_min, float in_max, float out_min, float out_max) {
  return (x - in_min) * (out_max - out_min) / (in_max - in_min) + out_min;
}