#include <Arduino.h>

// --- Піни ---
#define LED1 PA0
#define LED2 PA1
#define LED3 PA2
#define LED4 PA3
#define BUTTON PA4
#define PWM_OUT PA5

// --- LED ---
bool ledState = false;
int blinkFreq = 1;
unsigned long lastBlink = 0;
unsigned long blinkInterval = 500;

// --- Сигнали ---
enum SignalType { NONE, SIN, RAMP };
SignalType signalMode = NONE;
float signalFreq = 0;

// --- Таблиця синуса (32 точки) ---
const uint8_t sinTable[32] = {
  128, 152, 176, 198, 218, 234, 246, 253,
  255, 253, 246, 234, 218, 198, 176, 152,
  128, 104,  80,  58,  38,  22,  10,   3,
    0,   3,  10,  22,  38,  58,  80, 104
};
uint8_t sinIndex = 0;

// --- Рамп генератор ---
uint8_t rampValue = 0;

// --- Таймери ---
unsigned long lastSignal = 0;
const int sampleRate = 2000; // 2 kHz

// --- Тестові команди ---
int currentCmd = 0;
unsigned long lastCmdTime = 0;

// -------------------- TASK: LED --------------------
void taskLED() {
  unsigned long now = millis();
  if (now - lastBlink >= blinkInterval) {
    lastBlink = now;
    ledState = !ledState;
    digitalWrite(LED1, ledState);
    digitalWrite(LED2, ledState);
    digitalWrite(LED3, ledState);
    digitalWrite(LED4, ledState);
  }

  static bool lastBtn = HIGH;
  bool btn = digitalRead(BUTTON);
  if (btn == LOW && lastBtn == HIGH) {
    if (blinkFreq == 1) {
      blinkFreq = 2; blinkInterval = 250;
    } else {
      blinkFreq = 1; blinkInterval = 500;
    }
  }
  lastBtn = btn;
}

// -------------------- TASK: COMMAND --------------------
void taskCommand() {
  unsigned long now = millis();
  if (now - lastCmdTime > 5000) {
    if (currentCmd == 0) { signalMode = SIN; signalFreq = 500; }   // SIN 0.5 kHz
    else if (currentCmd == 1) { signalMode = RAMP; signalFreq = 500; } // RAMP 0.5 kHz
    else if (currentCmd == 2) { signalMode = NONE; analogWrite(PWM_OUT, 0); } // STOP
    currentCmd++;
    lastCmdTime = now;
  }
}

// -------------------- TASK: SIGNAL --------------------
void taskSignal() {
  if (signalMode == NONE) return;

  unsigned long now = micros();
  if (now - lastSignal >= (1000000 / sampleRate)) {
    lastSignal = now;
    int value = 0;

    if (signalMode == SIN) {
      value = sinTable[sinIndex];
      sinIndex = (sinIndex + 1) % 32;
    } else if (signalMode == RAMP) {
      value = rampValue;
      rampValue += 8;
    }

    analogWrite(PWM_OUT, value); // 8-біт PWM
  }
}

// -------------------- SETUP --------------------
void setup() {
  pinMode(LED1, OUTPUT);
  pinMode(LED2, OUTPUT);
  pinMode(LED3, OUTPUT);
  pinMode(LED4, OUTPUT);
  pinMode(BUTTON, INPUT_PULLUP);
  pinMode(PWM_OUT, OUTPUT);
  analogWrite(PWM_OUT, 0);
}

// -------------------- LOOP --------------------
void loop() {
  taskLED();
  taskCommand();
  taskSignal();
}