/*
  程序：Message Buffer

*/
#include <freertos/message_buffer.h>
#include <LiquidCrystal_I2C.h>

LiquidCrystal_I2C lcd(0x27, 20, 4);

MessageBufferHandle_t xMessageBuffer = NULL;

void readGPS(void *pvParam)
{
  size_t xBytesSent;//The number of bytes written to the message buffer.
  String gpsInfo;
  while (1) {
    gpsInfo = randomGPS();//随机发送不同长度的信息
    xBytesSent = xMessageBufferSend(xMessageBuffer,
                                    (void *)&gpsInfo,
                                    sizeof(gpsInfo),
                                    portMAX_DELAY);

    if (xBytesSent != sizeof(gpsInfo)) {
      Serial.println("危险：xMessageBufferSend 发送数据不完整");
    }
    vTaskDelay(3000);
  }
}

void showGPS(void *pvParam)
{
  size_t xReceivedBytes;
  String gpsInfo;
  const size_t xMessageSizeMax = 100;
  lcd.init();
  lcd.backlight();
  lcd.setCursor(0, 0);
  lcd.print("  GPS INFO");//clear this line
  while (1) {
    xReceivedBytes = xMessageBufferReceive(xMessageBuffer,
                                         (void *)&gpsInfo,
                                         xMessageSizeMax,//This sets the maximum length of the message that can be received.
                                         portMAX_DELAY);

    if(xReceivedBytes > 0){
      gpsDecoder(gpsInfo);//解码，并且显示到屏幕上
    }  
    vTaskDelay(1000); 
  }
}

void monitorTask(void *pvParam)
{
  size_t xAvailable,xUsed;
  bool isFull;
  while(1){
    //Queries a stream buffer to see if it is full.
    if(xMessageBufferIsFull(xMessageBuffer)  == pdTRUE) Serial.println("xMessageBuffer is full");
    //Queries a stream buffer to see how much free space it contains
    xAvailable = xMessageBufferSpacesAvailable(xMessageBuffer);

    char msg[40];
    sprintf(msg,"xMessageBuffer可用空间为 %d 字节",xAvailable);
    Serial.println(msg);

    vTaskDelay(1000);
  }
}

void setup() {
  // put your setup code here, to run once:
  Serial.begin(115200);
  Serial.println("Hello, ESP32!");
  const size_t xMessageBufferSizeBytes = 100;
  xMessageBuffer = xMessageBufferCreate(xMessageBufferSizeBytes);

  if(xMessageBuffer == NULL){
    Serial.println("Unable to create message buffer");
  }else{
    xTaskCreate(readGPS,"Read GPX",1024*4,NULL,1,NULL);
    xTaskCreate(showGPS,"Show GPX",1024*4,NULL,1,NULL);
    xTaskCreate(monitorTask,"Monitor Message Buffer",1024*8,NULL,1,NULL);//对Stream Buffer进行监控
  }
}

void loop() {
  // put your main code here, to run repeatedly:
  delay(10); // this speeds up the simulation
}