#include <Wire.h>
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>
#include <ShiftRegister74HC595.h>

#define SCREEN_WIDTH 128
#define SCREEN_HEIGHT 64
Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, -1);

// ===== Configuración de 74HC595 =====
#define DATA_PIN   23
#define LATCH_PIN  5
#define CLOCK_PIN  18
#define NUM_SHIFT_REGS 4
#define NUM_LEDS (NUM_SHIFT_REGS * 8)

ShiftRegister74HC595<NUM_SHIFT_REGS> sr(DATA_PIN, CLOCK_PIN, LATCH_PIN);

// ===== Botones =====
#define BTN_PLAYPAUSE 32
#define BTN_START     33
#define BTN_SEQ1      25
#define BTN_SEQ2      26

// ===== Variables =====
bool isRunning = false;
int currentSequence = 0;
unsigned long lastUpdate = 0;
unsigned long interval = 150;
int stepIndex = 0;
int blockSize = 2;
int maxBlock = 6;

// ===== Nombres de secuencias =====
const char* sequenceNames[8] = {
  "Barrido der",
  "Barrido izq",
  "Rebote",
  "Relleno der",
  "Relleno izq",
  "Todos ON/OFF",
  "Pares/Impares",
  "Bloques 2-6"
};

// ===== Funciones de LEDs =====
void clearAll() {
  for (int i = 0; i < NUM_LEDS; i++) sr.set(i, LOW);
}
void setLed(int index, bool state) {
  if (index >= 0 && index < NUM_LEDS) sr.set(index, state);
}

// ===== Secuencias =====
void doSequence1() {
  clearAll();
  setLed(stepIndex, HIGH);
  stepIndex++;
  if (stepIndex >= NUM_LEDS) stepIndex = 0;
}

void doSequence2() {
  clearAll();
  setLed(NUM_LEDS - 1 - stepIndex, HIGH);
  stepIndex++;
  if (stepIndex >= NUM_LEDS) stepIndex = 0;
}

void doSequence3() {
  clearAll();
  setLed(stepIndex, HIGH);
  setLed(NUM_LEDS - 1 - stepIndex, HIGH);
  stepIndex++;
  if (stepIndex >= NUM_LEDS / 2) stepIndex = 0;
}

void doSequence4() {
  clearAll();
  for (int i = 0; i <= stepIndex; i++) setLed(i, HIGH);
  stepIndex++;
  if (stepIndex >= NUM_LEDS) stepIndex = 0;
}

void doSequence5() {
  clearAll();
  for (int i = 0; i <= stepIndex; i++) setLed(NUM_LEDS - 1 - i, HIGH);
  stepIndex++;
  if (stepIndex >= NUM_LEDS) stepIndex = 0;
}

void doSequence6() {
  clearAll();
  for (int i = 0; i < NUM_LEDS; i++) setLed(i, (stepIndex % 2 == 0));
  stepIndex++;
  if (stepIndex >= 2) stepIndex = 0;
}

void doSequence7() {
  clearAll();
  for (int i = 0; i < NUM_LEDS; i++) {
    if (i % 2 == stepIndex % 2) setLed(i, HIGH);
  }
  stepIndex++;
  if (stepIndex >= 2) stepIndex = 0;
}

void doSequence8() {
  clearAll();
  for (int i = 0; i < blockSize; i++) {
    int pos = (stepIndex + i) % NUM_LEDS;
    setLed(pos, true);
  }
  stepIndex += blockSize;
  if (stepIndex >= NUM_LEDS) {
    stepIndex = 0;
    blockSize++;
    if (blockSize > maxBlock) blockSize = 2;
  }
}

// ===== Mostrar en OLED =====
void updateOLED() {
  display.clearDisplay();
  display.setTextSize(1);
  display.setTextColor(SSD1306_WHITE);

  display.setCursor(0, 0);
  display.print("Secuencia: ");
  display.println(currentSequence + 1);

  display.setCursor(0, 12);
  display.print(sequenceNames[currentSequence]);

  display.setCursor(0, 28);
  display.print("Estado: ");
  display.println(isRunning ? "PLAY" : "PAUSE");

  display.setCursor(0, 44);
  display.print("Paso: ");
  display.println(stepIndex);

  // Mostrar tamaño de bloque solo en secuencia 8
  if (currentSequence == 7) {
    display.setCursor(70, 44);
    display.print("Bloque: ");
    display.println(blockSize);
  }

  display.display();
}

// ===== Control de secuencias =====
void runSequence() {
  switch (currentSequence) {
    case 0: doSequence1(); break;
    case 1: doSequence2(); break;
    case 2: doSequence3(); break;
    case 3: doSequence4(); break;
    case 4: doSequence5(); break;
    case 5: doSequence6(); break;
    case 6: doSequence7(); break;
    case 7: doSequence8(); break;
  }
}

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

  pinMode(BTN_PLAYPAUSE, INPUT_PULLUP);
  pinMode(BTN_START, INPUT_PULLUP);
  pinMode(BTN_SEQ1, INPUT_PULLUP);
  pinMode(BTN_SEQ2, INPUT_PULLUP);

  if (!display.begin(SSD1306_SWITCHCAPVCC, 0x3C)) {
    Serial.println("No se encuentra OLED SSD1306");
    for (;;);
  }
  display.display();
  delay(1000);

  clearAll();
  updateOLED();
}

void loop() {
  // Botón PLAY/PAUSE
  if (digitalRead(BTN_PLAYPAUSE) == LOW) {
    delay(200);
    isRunning = !isRunning;
    updateOLED();
  }
  // Botón START
  if (digitalRead(BTN_START) == LOW) {
    delay(200);
    isRunning = true;
    updateOLED();
  }
  // Botón SEQ1 (siguiente)
  if (digitalRead(BTN_SEQ1) == LOW) {
    delay(200);
    currentSequence = (currentSequence + 1) % 8;
    stepIndex = 0;
    blockSize = 2;
    updateOLED();
  }
  // Botón SEQ2 (anterior)
  if (digitalRead(BTN_SEQ2) == LOW) {
    delay(200);
    currentSequence = (currentSequence - 1 + 8) % 8;
    stepIndex = 0;
    blockSize = 2;
    updateOLED();
  }

  // Secuencias
  if (isRunning && millis() - lastUpdate > interval) {
    lastUpdate = millis();
    runSequence();
    updateOLED();
  }
}