#include <ESP8266WiFi.h>
#include <algorithm> 
#include <ESP8266WiFiMulti.h>

#ifndef STASSID
#define STASSID "esp8266"  //WIFI名
#define STAPSK  "12345678" //WIFI密码
#endif

#define BAUD_SERIAL 115200  // 串口波特率115200

#define RXBUFFERSIZE 1024  //设置串口接收的字节大小

//最多的连接个数
#define MAX_SRV_CLIENTS 4

const char* ssid = STASSID;  //wifi名字
const char* password = STAPSK;//wifi密码

const int port = 30;    //服务器端口30

WiFiServer server(port);   //创建服务器对象
WiFiClient serverClients[MAX_SRV_CLIENTS]; //连接对象数组

ESP8266WiFiMulti WiFiMulti;

struct UserInfo{
	char humi_value;
	char temp_value;
	char temp_pig;
	char temp_threshold;
	char humi_threshold;
	char cleanFlag;
	char feedFlag;
};

int getSum(char *data, int length){
	int sum = 0, i = 0;
	for(i = 0; i < length; i++){
		sum += data[i];
	}
	return sum;
}

char deserialization(struct UserInfo *usr, char* data, int length){
	if(length != 13) return -1;
	if(data[length - 1] != 0x0D || data[0] != 0xFD) return -1;
	if(getSum(data, length - 3) != (data[length - 3] * 256 + data[length - 2])) return -1;
	usr->temp_value = data[3];
	usr->humi_value = data[4];
	usr->temp_pig = data[5];
	usr->temp_threshold = data[6];
	usr->humi_threshold = data[7];
	usr->cleanFlag  = data[8];
	usr->feedFlag = data[9];
	return 0;
}

char serialize(struct UserInfo *usr, char* data, int length){
  int sum = 0;
  if(length != 13) return -1;
  data[0] = 0xFD;
  data[1] = 0x00;
  data[2] = 0x01;
  data[3] = usr->temp_value;
  data[4] = usr->humi_value;
  data[5] = usr->temp_pig;
  data[6] = usr->temp_threshold;
  data[7] = usr->humi_threshold;
  data[8] = usr->cleanFlag;
  data[9] = usr->feedFlag;
  sum = getSum(data, 10);
  data[10] = sum >> 8;
  data[11] = sum & 0x00FF;
  data[12] = 0x0D;
  return 0;
}

// 初始化函数
void setup() {
  Serial.begin(BAUD_SERIAL); // 串口初始化
  Serial.setRxBufferSize(RXBUFFERSIZE); //串口接收的初始化

  pinMode(LED_BUILTIN, OUTPUT);      //配置LED灯
  digitalWrite(LED_BUILTIN, HIGH);   //LED置高

  //设置客户端模式
  WiFi.mode(WIFI_STA);
  //连接网络
  WiFiMulti.addAP(ssid, password);
  Serial.println(ssid);
  Serial.println(password);
    // 等待连接WIFI
  while (WiFiMulti.run() != WL_CONNECTED) {
    Serial.print(".");
    delay(500);
  }
  Serial.println("");
  Serial.println("WiFi connected");
  Serial.println("IP address: ");
  Serial.println(WiFi.localIP());  //获取自身IP地址
  delay(500);
  //启动服务器
  server.begin();
  server.setNoDelay(true);  //关闭小包合并包模式并去除延时
}

// loop函数
void loop() {
  //如果新的连接请求
  if (server.hasClient()) 
  {
    int i = 0;
    for (i = 0; i < MAX_SRV_CLIENTS; i++)
    {
      if (!serverClients[i]) //遍历连接
      { 
        serverClients[i] = server.available();//建立新的连接
        Serial.print("New:");
        Serial.print(i+1);
        break;
      }
    }
    //如果连接数量已经达到最大
    if (i == MAX_SRV_CLIENTS) 
    {
      WiFiClient client = server.available();
      client.stop();
      Serial.print("stop\n");
    }
  }
  //检测客户端发送上来的信息
  for (int i = 0; i < MAX_SRV_CLIENTS; i++)
  {
    //如果该客户端处于连接状态
    if(serverClients[i] && serverClients[i].connected())
    {
      while(serverClients[i].available())
      {
        uint8_t c = serverClients[i].read();
        Serial.write(c);
      }
    }
  }
  // 如果串口接收到数据
  if(Serial.available())
  {
    delay(10);
    size_t counti = Serial.available();
    uint8_t sbuf[counti];
    Serial.readBytes(sbuf, counti);
    for (int i = 0; i < MAX_SRV_CLIENTS; i++)
    {
      // 如果客户端还处于连接状态
      if(serverClients[i] && serverClients[i].connected())
      {
        serverClients[i].write(sbuf,counti);     //将串口接收到的数据发送到各个客户端
      }
    }
  }
}