#include <SPI.h> // Include the SPI library for ESP32

// Define the SPI pins for the ESP32
// These should match how you've wired them in Wokwi,
// and conceptually match the pins defined in your custom chip.
// For ESP32, typical VSPI pins:
#define SCK_PIN  18
#define MISO_PIN 19
#define MOSI_PIN 23
#define CS_PIN   5 // You can choose any available GPIO for CS

// Buffer to store received image data
// This should be the same size as BUFFER_LEN in your custom chip
// (which is 120 * 160 = 19200 bytes)
#define IMAGE_BUFFER_SIZE (120 * 160)
byte imageData[IMAGE_BUFFER_SIZE];

void setup() {
  Serial.begin(115200);
  while (!Serial); // Wait for serial port to connect

  Serial.println("ESP32 SPI Camera Master Example");

  // Set up the Chip Select pin as an output
  pinMode(CS_PIN, OUTPUT);
  digitalWrite(CS_PIN, HIGH); // Ensure CS is high (inactive) initially

  // Initialize the SPI bus
  // The ESP32 has two SPI buses (HSPI and VSPI). VSPI is generally preferred for user applications.
  // SPI.begin(SCK, MISO, MOSI, SS) or SPI.begin() for default pins.
  // We'll explicitly set the pins here for clarity.
  SPI.begin(SCK_PIN, MISO_PIN, MOSI_PIN, -1); // -1 means don't use default SS (we'll manage CS_PIN manually)
  SPI.setClockDivider(SPI_CLOCK_DIV8); // Set SPI speed (e.g., F_CPU/8)
  SPI.setBitOrder(MSBFIRST);           // Most Significant Bit first
  SPI.setDataMode(SPI_MODE0);          // SPI Mode 0

  Serial.println("SPI Initialized.");
}

void loop() {
  Serial.println("\nRequesting image data from camera...");

  // Select the camera (pull CS low)
  digitalWrite(CS_PIN, LOW);
  delayMicroseconds(10); // Small delay for chip to react

  // Read data from the camera
  // The custom chip is configured to send BUFFER_LEN bytes when CS is low.
  // We will read that many bytes.
  for (int i = 0; i < IMAGE_BUFFER_SIZE; i++) {
    // Send a dummy byte (0x00) and receive a byte from the slave
    imageData[i] = SPI.transfer(0x00);
    // You can print a few bytes to verify data is coming through
    // if (i < 20 || i > IMAGE_BUFFER_SIZE - 20) { // Print first/last 20 bytes
    //   Serial.printf("Byte %d: 0x%02X\n", i, imageData[i]);
    // }
  }

  // Deselect the camera (pull CS high)
  digitalWrite(CS_PIN, HIGH);

  Serial.printf("Received %d bytes of image data.\n", IMAGE_BUFFER_SIZE);

  // At this point, imageData array contains the simulated image data.
  // You would typically process this data here (e.g., display on a screen,
  // save to SD card, send over network, etc.).
  // For now, we'll just confirm receipt.

  delay(5000); // Wait 5 seconds before requesting another image
}