// Based on https://drive.google.com/file/d/1w8hJ5NhNik3qo2xl6eDrlgG4n6R4LuJ_/view
#include "quirc.h"

struct QRCodeData
{
  bool valid;
  int dataType;
  uint8_t payload[1024];
  int payloadLen;
};

// creating a task handle
TaskHandle_t QRCodeReader_Task; 

struct quirc *q = NULL;
uint8_t *image = NULL;  
camera_fb_t * fb = NULL;
struct quirc_code code;
struct quirc_data data;
quirc_decode_error_t err;
struct QRCodeData qrCodeData;  
String QRCodeResult = "";

void qr_reader_setup() {
  // camera init

  camera_config_t config;
  config.ledc_channel = LEDC_CHANNEL_0;
  config.ledc_timer = LEDC_TIMER_0;
  config.pin_d0 = Y2_GPIO_NUM;
  config.pin_d1 = Y3_GPIO_NUM;
  config.pin_d2 = Y4_GPIO_NUM;
  config.pin_d3 = Y5_GPIO_NUM;
  config.pin_d4 = Y6_GPIO_NUM;
  config.pin_d5 = Y7_GPIO_NUM;
  config.pin_d6 = Y8_GPIO_NUM;
  config.pin_d7 = Y9_GPIO_NUM;
  config.pin_xclk = XCLK_GPIO_NUM;
  config.pin_pclk = PCLK_GPIO_NUM;
  config.pin_vsync = VSYNC_GPIO_NUM;
  config.pin_href = HREF_GPIO_NUM;
  config.pin_sscb_sda = SIOD_GPIO_NUM;
  config.pin_sscb_scl = SIOC_GPIO_NUM;
  config.pin_pwdn = PWDN_GPIO_NUM;
  config.pin_reset = RESET_GPIO_NUM;
  config.xclk_freq_hz = 10000000;
  config.pixel_format = PIXFORMAT_GRAYSCALE;
  config.frame_size = FRAMESIZE_QVGA;
  config.jpeg_quality = 15;
  config.fb_count = 1;
  
  /*#if defined(CAMERA_MODEL_ESP_EYE)
    pinMode(13, INPUT_PULLUP);
    pinMode(14, INPUT_PULLUP);
  #endif*/

  esp_err_t err = esp_camera_init(&config);
  if (err != ESP_OK) {
    Serial.printf("Camera init failed with error 0x%x", err);
    ESP.restart();
  }
  
  sensor_t * s = esp_camera_sensor_get();
  s->set_framesize(s, FRAMESIZE_QVGA);
  
  //Serial.println("Configure and initialize the camera successfully.");
  //Serial.println();
  /* ---------------------------------------- */

  /* ---------------------------------------- create "QRCodeReader_Task" using the xTaskCreatePinnedToCore() function */
  xTaskCreatePinnedToCore(
             QRCodeReader,          /* Task function. */
             "QRCodeReader_Task",   /* name of task. */
             10000,                 /* Stack size of task */
             NULL,                  /* parameter of the task */
             1,                     /* priority of the task */
             &QRCodeReader_Task,    /* Task handle to keep track of created task */
             0);                    /* pin task to core 0 */
  /* ---------------------------------------- */
}

void qr_reader_loop() {
  delay(1);
}

void QRCodeReader( void * pvParameters ){
  /* ---------------------------------------- */
  Serial.println("Waiting for QR code");
  //Serial.print("QRCodeReader running on core ");
  //Serial.println(xPortGetCoreID());
  //Serial.println();
  /* ---------------------------------------- */

  /* ---------------------------------------- Loop to read QR Code in real time. */
  while(1){
      q = quirc_new();
      if (q == NULL){
        Serial.print("can't create quirc object\r\n");  
        continue;
      }
    
      fb = esp_camera_fb_get();
      if (!fb)
      {
        Serial.println("Camera capture failed");
        continue;
      }   
      
      quirc_resize(q, fb->width, fb->height);
      image = quirc_begin(q, NULL, NULL);
      memcpy(image, fb->buf, fb->len);
      quirc_end(q);
      
      int count = quirc_count(q);
      if (count > 0) {
        quirc_extract(q, 0, &code);
        err = quirc_decode(&code, &data);
    
        if (err){
          Serial.println("Decoding FAILED");
          QRCodeResult = "Decoding FAILED";
        } else {
          //Serial.printf("Decoding successful:\n");
          dumpData(&data);
        } 
        Serial.println();
      } 
      
      esp_camera_fb_return(fb);
      fb = NULL;
      image = NULL;  
      quirc_destroy(q);
  }
  /* ---------------------------------------- */
}

void dumpData(const struct quirc_data *data)
{
  /*Serial.printf("Version: %d\n", data->version);
  Serial.printf("ECC level: %c\n", "MLHQ"[data->ecc_level]);
  Serial.printf("Mask: %d\n", data->mask);
  Serial.printf("Length: %d\n", data->payload_len);*/
  Serial.printf("Payload: %s\n", data->payload);
  
  QRCodeResult = (const char *)data->payload;
}