// Nucleo + Wokwi: sensors + LCD1602A for Temp/Humidity display
// LCD1602A (HD44780 parallel, 4-bit):
//   RS=PB8, E=PB9, D4=PB10, D5=PB11, D6=PA11, D7=PB13, RW=GND
// Alimentazione: usa E5V nel diagramma (non 5V).

#include <LiquidCrystal.h>

#if defined(ARDUINO_ARCH_STM32)
  #define PIN_SOIL   PA0
  #define PIN_TEMP   PA1
  #define PIN_HUM    PA4
  #define PIN_TANK   PB1
  #define PIN_PUMP   PA5
  // LCD pins
  #define LCD_RS     PB8
  #define LCD_E      PB9
  #define LCD_D4     PB10
  #define LCD_D5     PB11
  #define LCD_D6     PA11
  #define LCD_D7     PB13
#else
  #error "Questo sketch è per STM32 (Arduino core)."
#endif

LiquidCrystal lcd(LCD_RS, LCD_E, LCD_D4, LCD_D5, LCD_D6, LCD_D7);

// ---- Parametri controllo ----
const float TH_LOW      = 40.0;                 // %
const float TH_HIGH     = 50.0;                 // %
const unsigned long T_ON_MAX_MS = 20000UL;      // 20 s

// ---- Campionamento / ADC ----
const unsigned SAMPLE_MS = 500;
const int   ADC_BITS = 12;                      // STM32: 12-bit
const float ADC_FS  = (float)((1 << ADC_BITS) - 1); // 4095
const float VREF    = 5.0;                      // chip 0..5V

bool pumpOn = false;
unsigned long pumpStartMs = 0;
unsigned long lastSample = 0;

static inline float clampf(float x, float lo, float hi) {
  if (x < lo) return lo;
  if (x > hi) return hi;
  return x;
}
static inline float readVoltage(int pin) {
  int raw = analogRead(pin);
  return (raw / ADC_FS) * VREF;
}
static inline float readPercentFromVoltage(float v) {
  return clampf((v / 5.0f) * 100.0f, 0.0f, 100.0f);
}

void setup() {
  Serial.begin(115200);
  delay(300);

  analogReadResolution(ADC_BITS);

  pinMode(PIN_PUMP, OUTPUT);
  digitalWrite(PIN_PUMP, LOW);
  pinMode(PIN_TANK, INPUT);

  // LCD
  lcd.begin(16, 2);
  lcd.clear();
  lcd.setCursor(0, 0); lcd.print("Irrigation demo");
  lcd.setCursor(0, 1); lcd.print("Temp/Hum display");
  delay(800);
}

void loop() {
  const unsigned long now = millis();
  if (now - lastSample < SAMPLE_MS) return;
  lastSample = now;

  // --- Letture ---
  const float vSoil = readVoltage(PIN_SOIL);
  const float vTemp = readVoltage(PIN_TEMP);
  const float vHum  = readVoltage(PIN_HUM);

  const float soilPct = readPercentFromVoltage(vSoil);
  const float humPct  = readPercentFromVoltage(vHum);
  const float tempC   = vTemp * 100.0f;  // LM35: 10 mV/°C

  const bool tankOK = (digitalRead(PIN_TANK) == HIGH);

  // --- Controllo (isteresi + timeout) ---
  if (!tankOK) {
    pumpOn = false;
  } else {
    if (!pumpOn && soilPct < TH_LOW) {
      pumpOn = true; pumpStartMs = now;
    }
    if (pumpOn && (soilPct >= TH_HIGH))               pumpOn = false;
    if (pumpOn && (now - pumpStartMs >= T_ON_MAX_MS)) pumpOn = false;
  }

  // --- Attuatore ---
  digitalWrite(PIN_PUMP, pumpOn ? HIGH : LOW);

  // --- LCD: scrivi NUMERI, pulendo ogni riga con 16 spazi ---
  // Riga 0: "T:xx.xC  H:yy.y%"
  lcd.setCursor(0, 0); lcd.print("                ");
  lcd.setCursor(0, 0);
  lcd.print("T:"); lcd.print(tempC, 1); lcd.print("C  ");
  lcd.print("H:"); lcd.print(humPct, 1); lcd.print("%");

  // Riga 1: stato rapido
  lcd.setCursor(0, 1); lcd.print("                ");
  lcd.setCursor(0, 1);
  lcd.print("P:"); lcd.print(pumpOn ? "ON " : "OFF");
  lcd.print(" Tank:"); lcd.print(tankOK ? "OK " : "NO ");

  // --- Serial log (opzionale) ---
  static uint32_t line = 0;
  if ((line++ % 16) == 0) {
    Serial.println(F(" time[s] | soil[%] | temp[C] | hum[%] | tank | pump "));
    Serial.println(F("---------+--------+---------+--------+------+------"));
  }
  Serial.print(now / 1000.0f, 1); Serial.print("    | ");
  Serial.print(soilPct, 1);       Serial.print("    | ");
  Serial.print(tempC, 1);         Serial.print("    | ");
  Serial.print(humPct, 1);        Serial.print("    | ");
  Serial.print(tankOK ? "OK" : "NO"); Serial.print("   | ");
  Serial.println(pumpOn ? "ON" : "OFF");
}