#include <Adafruit_NeoPixel.h>

// Grid dimensions
const int NUM_COLS = 9;           // Number of columns in the grid (x-axis)
const int NUM_ROWS = 5;           // Number of rows in the grid (y-axis)
const int NUM_LEDS = NUM_COLS * NUM_ROWS;  // Total number of LEDs

// Pin definitions
#define LED_PIN    6      // Digital pin connected to NeoPixel DIN
#define MIC_PIN    A0     // Analog pin reading the amplified microphone signal

// Create the NeoPixel object
Adafruit_NeoPixel strip = Adafruit_NeoPixel(NUM_LEDS, LED_PIN, NEO_GRB + NEO_KHZ800);

int waveform[NUM_COLS];

int XY(int x, int y) {
  int row = (NUM_ROWS - 1) - y;
  return row * NUM_COLS + x;
}

void setup() {
  strip.begin();
  strip.show();   // Clear all pixels initially
  Serial.begin(115200);

  for (int i = 0; i < NUM_COLS; i++) {
    waveform[i] = 1;
  }
}

void loop() {
  int micValue = analogRead(MIC_PIN);
  Serial.println(micValue); // debug

  int deviation = micValue - 512;
  
  int y = map(deviation, -512, 511, 0, NUM_ROWS - 1);
  
  for (int x = 0; x < NUM_COLS - 1; x++) {
    waveform[x] = waveform[x + 1];
  }
  
  waveform[NUM_COLS - 1] = y;
  
  strip.clear();
  
  for (int x = 0; x < NUM_COLS; x++) {
    int row = waveform[x];
    int pixelIndex = XY(x, row);
    strip.setPixelColor(pixelIndex, strip.Color(0, 255, 0));
  }
  
  strip.show();
  
  delay(30);
}