// ============================================================
//  AUTOMATED PLANT WATERING SYSTEM – Hydroponic + IoT
//  Student : Cisca Bougard  |  47655232  |  EIP3702
//  Mentor  : Prof. B.B. Monchusi  |  UNISA
//
//  Platform   : Wokwi – ESP32 DevKit V1
//  Simulation : All sensors + fuzzy logic + LCD + pump LEDs
// ============================================================

#include <Wire.h>
#include <LiquidCrystal_I2C.h>
#include <DHT.h>
#include <OneWire.h>
#include <DallasTemperature.h>
#include <WiFi.h>
#include <WebServer.h>
#include <WiFiClientSecure.h>
#include <HTTPClient.h>

// ── Pin definitions ──────────────────────────────────────────
#define DHT_PIN         4
#define DHT_TYPE        DHT22
#define DS18B20_PIN     15
#define PH_PIN          34
#define EC_PIN          35
#define TRIG_PIN        5
#define ECHO_PIN        18
#define PUMP_IRRIGATE   25
#define PUMP_PH_UP      26
#define PUMP_PH_DOWN    27
#define PUMP_NUTRIENT   32
#define LED_OK          13
#define LED_ALERT       2

// ── Setpoints ────────────────────────────────────────────────
#define PH_MIN        5.5f
#define PH_MAX        6.5f
#define EC_MIN        1.2f
#define EC_MAX        2.4f
#define LEVEL_SAFE    15.0f
#define CYCLE_MS      10000UL
#define IRRIGATE_MS   5000UL
#define REPORT_INTERVAL 60000UL   // 1 minute

// ── Objects ───────────────────────────────────────────────────
LiquidCrystal_I2C lcd(0x27, 16, 2);

DHT dht(DHT_PIN, DHT_TYPE);
OneWire ow(DS18B20_PIN);
DallasTemperature waterTempSensor(&ow);

// ── State ─────────────────────────────────────────────────────
float  ph = 6.0, ec = 1.8, wt = 20.0, at = 23.0, hum = 65.0;
float  levelCm = 8.0;
bool   systemOK   = true;
bool   irrigating = false;
// FIX 1: All alert flags and timing variables declared together cleanly
bool alertLevelSent = false;
bool alertPhSent    = false;
bool alertEcSent    = false;
unsigned long lastReport = 0;
unsigned long lastTelegramTime = 0;  // FIX 3: was referenced but never declared

int    cycleNum   = 0;
int    lcdPage    = 0;
unsigned long lastCycle     = 0;
unsigned long irrigateStart = 0;
unsigned long lastLcdSwitch = 0;

// ── WiFi / Web Server ─────────────────────────────────────────
const char* ssid = "Wokwi-GUEST";
const char* password = "";

WebServer server(80);
// ── Telegram Settings ─────────────────────────────────────────
String botToken = "8764021108:AAFnamV_UHiXsKsKRGuT26Vp1g0T4fsAQ";
String chatID   = "1402039912";

// ── Sensor reads ──────────────────────────────────────────────
float readPH()  { return 3.0f + (analogRead(PH_PIN)  / 4095.0f) * 6.0f; }
float readEC()  { return        (analogRead(EC_PIN)   / 4095.0f) * 5.0f; }

float readLevel() {
  digitalWrite(TRIG_PIN, LOW);  delayMicroseconds(2);
  digitalWrite(TRIG_PIN, HIGH); delayMicroseconds(10);
  digitalWrite(TRIG_PIN, LOW);
  long t = pulseIn(ECHO_PIN, HIGH, 30000UL);
  return (t == 0) ? 99.0f : (t * 0.0343f) / 2.0f;
}

// ── Fuzzy logic ───────────────────────────────────────────────
float triMF(float x, float a, float b, float c) {
  if (x<=a||x>=c) return 0;
  return x<b ? (x-a)/(b-a) : (c-x)/(c-b);
}
float trapMF(float x, float a, float b, float c, float d) {
  if (x<=a||x>=d) return 0;
  if (x>=b&&x<=c) return 1;
  return x<b ? (x-a)/(b-a) : (d-x)/(d-c);
}
float fuzzyDemand() {
  float dp    = abs(ph - 6.0f);
  float ph_ok = triMF(dp,0,0,0.5f), ph_off=triMF(dp,0.3f,0.7f,1.2f), ph_bad=trapMF(dp,0.8f,1.2f,3,3);
  float ec_lo = trapMF(ec,0,0,1.0f,1.4f), ec_ok=triMF(ec,1,1.8f,2.6f), ec_hi=trapMF(ec,2.2f,2.6f,5,5);
  float r1=min(ph_ok,ec_ok), r2=ph_off, r3=ec_lo, r4=max(ph_bad,ec_hi);
  float num=r1*0.10f+r2*0.45f+r3*0.60f+r4*0.90f;
  float den=r1+r2+r3+r4;
  return (den<0.001f) ? 0 : constrain(num/den,0,1);
}

// ── LCD update ────────────────────────────────────────────────
void updateLCD() {
  if (millis() - lastLcdSwitch < 3000) return;
  lastLcdSwitch = millis();
  lcd.clear();

  if (lcdPage == 0) {
    lcd.setCursor(0, 0);
    lcd.print("pH:");
    lcd.print(ph, 1);
    lcd.print(ph < PH_MIN ? " LOW " : ph > PH_MAX ? " HIGH" : " OK  ");
    lcd.setCursor(0, 1);
    lcd.print("EC:");
    lcd.print(ec, 1);
    lcd.print(ec < EC_MIN ? " LOW " : ec > EC_MAX ? " HIGH" : " OK  ");

  } else if (lcdPage == 1) {
    lcd.setCursor(0, 0);
    lcd.print("WT:");
    lcd.print(wt, 1);
    lcd.print("C AT:");
    lcd.print(at, 0);
    lcd.setCursor(0, 1);
    lcd.print("Lvl:");
    lcd.print(levelCm, 0);
    lcd.print("cm ");
    lcd.print(systemOK ? "SAFE" : "LOW!");

  } else {
    lcd.setCursor(0, 0);
    lcd.print("IRR:");
    lcd.print(digitalRead(PUMP_IRRIGATE) ? "ON  " : "off ");
    lcd.print("pHU:");
    lcd.print(digitalRead(PUMP_PH_UP) ? "ON" : "of");
    lcd.setCursor(0, 1);
    lcd.print("pHD:");
    lcd.print(digitalRead(PUMP_PH_DOWN) ? "ON  " : "off ");
    lcd.print("NUT:");
    lcd.print(digitalRead(PUMP_NUTRIENT) ? "ON" : "of");
  }
  lcdPage = (lcdPage + 1) % 3;
}

// ── Serial telemetry ──────────────────────────────────────────
void printTelemetry() {
  float dem = fuzzyDemand();
  Serial.println(F("\n=========================================="));
  Serial.println(F("  AUTOMATED HYDROPONIC WATERING SYSTEM"));
  Serial.println(F("  Cisca Bougard | 47655232 | UNISA"));
  Serial.println(F("------------------------------------------"));
  Serial.print(F("  Cycle #")); Serial.println(cycleNum);
  Serial.println(F("------------------------------------------"));
  Serial.print(F("  pH          : ")); Serial.print(ph, 2);
  Serial.println(ph<PH_MIN?" << TOO LOW  -> pH-Up ON":ph>PH_MAX?" << TOO HIGH -> pH-Down ON":"  [OK 5.5-6.5]");
  Serial.print(F("  EC (mS/cm)  : ")); Serial.print(ec, 2);
  Serial.println(ec<EC_MIN?" << LOW  -> Nutrient ON":ec>EC_MAX?" << HIGH -> Alert":"  [OK 1.2-2.4]");
  Serial.print(F("  Water temp  : ")); Serial.print(wt, 1); Serial.println(F(" C"));
  Serial.print(F("  Air temp    : ")); Serial.print(at, 1); Serial.println(F(" C"));
  Serial.print(F("  Humidity    : ")); Serial.print(hum, 0); Serial.println(F(" %"));
  Serial.print(F("  Level       : ")); Serial.print(levelCm, 1);
  Serial.println(systemOK ? F(" cm [SAFE]") : F(" cm [LOW - ALERT]"));
  Serial.print(F("  Fuzzy demand: ")); Serial.print(dem, 2);
  Serial.println(dem > 0.35f ? F("  -> IRRIGATE") : F("  -> hold"));
  Serial.println(F("------------------------------------------"));
  Serial.print(F("  Irrigation  : ")); Serial.println(digitalRead(PUMP_IRRIGATE) ? F("ON <<") : F("off"));
  Serial.print(F("  pH-Up pump  : ")); Serial.println(digitalRead(PUMP_PH_UP)    ? F("ON <<") : F("off"));
  Serial.print(F("  pH-Dn pump  : ")); Serial.println(digitalRead(PUMP_PH_DOWN)  ? F("ON <<") : F("off"));
  Serial.print(F("  Nutrient    : ")); Serial.println(digitalRead(PUMP_NUTRIENT) ? F("ON <<") : F("off"));
  Serial.print(F("  System      : ")); Serial.println(systemOK ? F("OK") : F("ALERT"));
  Serial.println(F("=========================================="));
}

// ── Web page builder ──────────────────────────────────────────
String makePage() {
  String html = "<html><head><meta http-equiv='refresh' content='3'/>";
  html += "<style>body{font-family:Arial;text-align:center;} h1{color:#2E8B57;}</style>";
  html += "</head><body>";
  html += "<h1>Hydroponics IoT System</h1>";
  html += "<p><b>pH:</b> " + String(ph,2) + "</p>";
  html += "<p><b>EC:</b> " + String(ec,2) + "</p>";
  html += "<p><b>Water Temp:</b> " + String(wt,1) + " C</p>";
  html += "<p><b>Air Temp:</b> " + String(at,1) + " C</p>";
  html += "<p><b>Humidity:</b> " + String(hum,0) + " %</p>";
  html += "<p><b>Level:</b> " + String(levelCm,1) + " cm</p>";
  html += "<h3>Status: ";
  html += systemOK ? "OK" : "ALERT";
  html += "</h3>";
  html += "<h3>Pumps</h3>";
  html += "<p>Irrigation: " + String(digitalRead(PUMP_IRRIGATE) ? "ON" : "OFF") + "</p>";
  html += "<p>pH Up: " + String(digitalRead(PUMP_PH_UP) ? "ON" : "OFF") + "</p>";
  html += "<p>pH Down: " + String(digitalRead(PUMP_PH_DOWN) ? "ON" : "OFF") + "</p>";
  html += "<p>Nutrient: " + String(digitalRead(PUMP_NUTRIENT) ? "ON" : "OFF") + "</p>";
  html += "</body></html>";
  return html;
}
// ✅ ADD TELEGRAM FUNCTION HERE (OUTSIDE)
void sendTelegram(String message) {

  WiFiClientSecure client;
  client.setInsecure();

  HTTPClient http;

  // URL encode
  message.replace("%", "%25");
  message.replace(" ", "%20");
  message.replace("\n", "%0A");
  message.replace("#", "%23");

  String url =
    "https://api.telegram.org/bot" + botToken +
    "/sendMessage?chat_id=" + chatID +
    "&text=" + message;

  Serial.println(url);

  http.begin(client, url);

  int httpCode = http.GET();

  Serial.print("Telegram HTTP Code: ");
  Serial.println(httpCode);

  if (httpCode > 0) {
    String payload = http.getString();
    Serial.println(payload);
  }
  else {
    Serial.println("Telegram request failed");
  }

  http.end();
}

// ✅ COPY THE MISSING FUNCTION HERE
void sendFullReport() {

  String msg = "📊 Hydroponic Report\n";
  msg += "-------------------\n";

  msg += "pH: " + String(ph, 2) + "\n";
  msg += "EC: " + String(ec, 2) + " mS/cm\n";
  msg += "Water Temp: " + String(wt, 1) + " C\n";
  msg += "Air Temp: " + String(at, 1) + " C\n";
  msg += "Humidity: " + String(hum, 0) + " %\n";
  msg += "Water Level: " + String(levelCm, 1) + " cm\n";

  msg += systemOK ? "Status: OK ✅\n" : "Status: ALERT ⚠️\n";

  sendTelegram(msg);
}

// ── Setup ─────────────────────────────────────────────────────
void setup() {
  Serial.begin(115200);

  // Output pins
  int outPins[] = {PUMP_IRRIGATE, PUMP_PH_UP, PUMP_PH_DOWN,
                   PUMP_NUTRIENT, LED_OK, LED_ALERT, TRIG_PIN};
  for (int p : outPins) { pinMode(p, OUTPUT); digitalWrite(p, LOW); }
  pinMode(ECHO_PIN, INPUT);

  // Sensors
  dht.begin();
  waterTempSensor.begin();

  // LCD init
  Wire.begin(21, 22);
  delay(100);
  lcd.init();
  lcd.backlight();

  // Boot screen
  lcd.clear();
  lcd.setCursor(0, 0); lcd.print("  HydroponicSystem  ");
  lcd.setCursor(0, 1); lcd.print(" Cisca 47655232 ");
  delay(2000);
  lcd.clear();
  lcd.setCursor(0, 0); lcd.print("EIP3702  ");
  lcd.setCursor(0, 1); lcd.print("UNISA Booting...");
  delay(2000);
  lcd.clear();
  lcd.setCursor(0, 0); lcd.print("System Ready!   ");
  lcd.setCursor(0, 1); lcd.print("Starting in 10s ");

  Serial.println(F("\n=========================================="));
  Serial.println(F("  HYDROPONIC SYSTEM BOOT"));
  Serial.println(F("  Cisca Bougard | 47655232 | UNISA"));
  Serial.println(F("  EIP3702"));
  Serial.println(F("=========================================="));

  // Flash all LEDs to confirm wiring
  int allLEDs[] = {LED_OK, LED_ALERT, PUMP_IRRIGATE,
                   PUMP_PH_UP, PUMP_PH_DOWN, PUMP_NUTRIENT};
  for (int p : allLEDs) digitalWrite(p, HIGH);
  delay(600);
  for (int p : allLEDs) digitalWrite(p, LOW);
  digitalWrite(LED_OK, HIGH);  // green stays ON

  // WiFi connection
  WiFi.begin(ssid, password);
  Serial.print("Connecting to WiFi");
  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
    Serial.print(".");
  }
  Serial.println("\nWiFi connected!");
  Serial.println(WiFi.localIP());
  sendTelegram("✅ Hydroponic system is ONLINE!");

  // Web server
  server.on("/", []() {
    server.send(200, "text/html", makePage());
  });
  server.begin();
  Serial.println("Web server started!");

  lastCycle     = millis();
  lastLcdSwitch = millis();
  lastReport     = millis();        // FIX 4: initialise so first report isn't immediate
  lastTelegramTime = millis();
}

// ── Main loop ─────────────────────────────────────────────────
void loop() {
  unsigned long now = millis();
  server.handleClient();
  // ⏱️ Periodic Telegram report
if (now - lastReport > REPORT_INTERVAL) {
  sendFullReport();
  lastReport = now;
}

  // Sensor + control cycle every CYCLE_MS
  if (now - lastCycle >= CYCLE_MS) {
    lastCycle = now;
    cycleNum++;

    // Read sensors
    hum = dht.readHumidity();
    at  = dht.readTemperature();
    if (isnan(hum) || isnan(at)) { hum = 65.0f; at = 23.0f; }
    waterTempSensor.requestTemperatures();
    wt = waterTempSensor.getTempCByIndex(0);
    if (wt == DEVICE_DISCONNECTED_C) wt = 20.0f;
    ph      = readPH();
    ec      = readEC();
    levelCm = readLevel();
    systemOK = (levelCm < LEVEL_SAFE);
   

    // Status LEDs
    digitalWrite(LED_OK,    systemOK ? HIGH : LOW);
    digitalWrite(LED_ALERT, systemOK ? LOW  : HIGH);

    if (!systemOK) {
      // Safety interlock – reservoir low, shut all pumps
      digitalWrite(PUMP_PH_UP,    LOW);
      digitalWrite(PUMP_PH_DOWN,  LOW);
      digitalWrite(PUMP_NUTRIENT, LOW);
      digitalWrite(PUMP_IRRIGATE, LOW);
      irrigating = false;
    } else {
      // pH control
      if      (ph < PH_MIN) { digitalWrite(PUMP_PH_UP, HIGH); digitalWrite(PUMP_PH_DOWN, LOW); }
      else if (ph > PH_MAX) { digitalWrite(PUMP_PH_UP, LOW);  digitalWrite(PUMP_PH_DOWN, HIGH);}
      else                  { digitalWrite(PUMP_PH_UP, LOW);  digitalWrite(PUMP_PH_DOWN, LOW); }

      // EC / nutrient control
      digitalWrite(PUMP_NUTRIENT, ec < EC_MIN ? HIGH : LOW);

      // Fuzzy irrigation
      float dem = fuzzyDemand();
      if (!irrigating && dem > 0.35f) {
        digitalWrite(PUMP_IRRIGATE, HIGH);
        irrigating    = true;
        irrigateStart = now;
        Serial.print(F("[CTRL] Irrigation ON  demand="));
        Serial.println(dem, 2);
      }
    }
    printTelemetry();
  }

  // Irrigation auto-off
  if (irrigating && (millis() - irrigateStart >= IRRIGATE_MS)) {
    digitalWrite(PUMP_IRRIGATE, LOW);
    irrigating = false;
    Serial.println(F("[CTRL] Irrigation OFF (5s cycle complete)\n"));
  }

  // LCD cycles every 3 seconds independently
  updateLCD();

  delay(50); 
}