/*
 * ESP32 3-Phase SPWM - WOKWI PERFECT (NO WATCHDOG)
 */

#include <Arduino.h>

// ========== PIN ==========
const int pinU = 12, pinV = 14, pinW = 27;
const int pinButton = 13, pinPot = 34;
// ========== PWM ==========
const int pwmFreq = 5000, pwmRes = 8;
const float sinusFreq = 50.0;
const int LUT_SIZE = 256;
uint8_t sinLUT[LUT_SIZE];

volatile bool isRunning = false;
volatile float amplitude = 0.0, phase = 0.0;

// ========== SINUS LUT ==========
void initSinLUT() {
  for (int i = 0; i < LUT_SIZE; i++) {
    sinLUT[i] = (uint8_t)((sin(2 * PI * i / LUT_SIZE) + 1.0) * 127.5);
  }
  Serial.println("SinLUT OK");
}

inline uint8_t getSin(uint16_t idx) {
  return sinLUT[idx & (LUT_SIZE - 1)];
}

// ========== PWM ==========
void setupPWM() {
  ledcAttach(pinU, pwmFreq, pwmRes);
  ledcAttach(pinV, pwmFreq, pwmRes);
  ledcAttach(pinW, pwmFreq, pwmRes);
  Serial.println("PWM OK");
}

// ========== TIMER ==========
hw_timer_t *timer = NULL;
portMUX_TYPE timerMux = portMUX_INITIALIZER_UNLOCKED;

void IRAM_ATTR onTimer() {
  portENTER_CRITICAL_ISR(&timerMux);
  if (isRunning) {
    phase += 2 * PI * sinusFreq / pwmFreq;
    if (phase >= 2 * PI) phase -= 2 * PI;
    
    uint16_t idx = (uint16_t)(phase / (2 * PI) * LUT_SIZE);
    uint8_t sinU = getSin(idx);
    uint8_t sinV = getSin(idx + LUT_SIZE / 3);
    uint8_t sinW = getSin(idx + 2 * LUT_SIZE / 3);
    
    ledcWrite(pinU, (uint8_t)(sinU * amplitude));
    ledcWrite(pinV, (uint8_t)(sinV * amplitude));
    ledcWrite(pinW, (uint8_t)(sinW * amplitude));
  } else {
    ledcWrite(pinU, 0); ledcWrite(pinV, 0); ledcWrite(pinW, 0);
  }
  portEXIT_CRITICAL_ISR(&timerMux);
}

void setupTimer() {
  timer = timerBegin(1000000);
  timerAttachInterrupt(timer, &onTimer);
  timerAlarm(timer, 200, true, 0);  // 5kHz
  Serial.println("Timer 5kHz OK");
}

// ========== TASKS ==========
void readPotTask(void *pv) {
  int last = 0;
  while (1) {
    int raw = analogRead(pinPot);
    last = (last * 7 + raw) >> 3;
    amplitude = last / 4095.0;
    vTaskDelay(pdMS_TO_TICKS(20));
  }
}

void buttonTask(void *pv) {
  bool lastState = HIGH;
  while (1) {
    bool state = digitalRead(pinButton);
    if (lastState == HIGH && state == LOW) {
      isRunning = !isRunning;
      Serial.printf(">>> %s >>>\n", isRunning ? "START" : "STOP");
    }
    lastState = state;
    vTaskDelay(pdMS_TO_TICKS(50));
  }
}

// ========== SETUP ==========
void setup() {
  Serial.begin(115200);
  delay(1000);
  Serial.println("\n=== 3-PHASE SPWM WOKWI PERFECT ===");
  
  initSinLUT();
  setupPWM();
  setupTimer();
  pinMode(pinButton, INPUT_PULLUP);
  
  // TASKS
  xTaskCreatePinnedToCore(readPotTask, "Pot", 2048, NULL, 1, NULL, 0);
  xTaskCreatePinnedToCore(buttonTask, "Btn", 2048, NULL, 1, NULL, 0);
  
  Serial.println("🚀 READY! Pin13=BTN Pin34=POT");
}

// ========== LOOP ==========
void loop() {
  static uint32_t lastPrint = 0;
  if (millis() - lastPrint > 2000) {
    lastPrint = millis();
    Serial.printf("STATUS: %s | AMP: %.1f%% | PHASE: %.2f\n",
                  isRunning?"RUN":"STOP", amplitude*100, phase);
  }
  delay(10);
}