inkplate-6-arduino-library/examples/3. Projects/1-Weather_station_example/Network.cpp

//Network.cpp contains various functions and classes that enable Weather station
//They have been declared in seperate file to increase readability
#include "Network.h"

#include <WiFi.h>
#include <WiFiMulti.h>
#include <HTTPClient.h>
#include <WiFiClientSecure.h>

#include <ArduinoJson.h>

//WiFiMulti object declaration
WiFiMulti WiFiMulti;

//Static Json from ArduinoJson library
StaticJsonDocument<6000> doc;

//Declared week days
char weekDays[8][8] = {
    "Mon",
    "Tue",
    "Wed",
    "Thr",
    "Fri",
    "Sat",
    "Sun",
};

void Network::begin(char *city)
{
    //Initiating wifi, like in BasicHttpClient example
    WiFi.mode(WIFI_STA);
    WiFiMulti.addAP(ssid, pass);

    Serial.print(F("Waiting for WiFi to connect..."));
    while ((WiFiMulti.run() != WL_CONNECTED))
    {
        //Printing a dot to Serial monitor every second while waiting to connect
        Serial.print(F("."));
        delay(1000);
    }
    Serial.println(F(" connected"));

    //Find internet time
    setTime();

    //Search for given cities woeid
    findCity(city);

    //reduce power by making WiFi module sleep
    WiFi.setSleep(1);
}

//Gets time from ntp server
void Network::getTime(char *timeStr)
{
    //Get seconds since 1.1.1970.
    time_t nowSecs = time(nullptr);

    //Struct used to store time
    struct tm timeinfo;
    gmtime_r(&nowSecs, &timeinfo);

    //Copies time string into timeStr
    strncpy(timeStr, asctime(&timeinfo) + 11, 5);

    //Setting time string timezone
    int hr = 10 * timeStr[0] + timeStr[1] + timeZone;

    //Better defined modulo, in case timezone makes hours to go below 0
    hr = (hr % 24 + 24) % 24;

    //Adding time to '0' char makes it into whatever time char, for both digits
    timeStr[0] = hr / 10 + '0';
    timeStr[1] = hr % 10 + '0';
}

//Helper function to convert float to char*
void formatTemp(char *str, float temp)
{
    //Built in function for float to char* conversion
    dtostrf(temp, 2, 0, str);
}

//Helper function to convert float to char*
void formatWind(char *str, float wind)
{
    //Built in function for float to char* conversion
    dtostrf(wind, 2, 0, str);
}

//Function that connects to API and gets the weather data
void Network::getData(char *city, char *temp1, char *temp2, char *temp3, char *temp4, char *currentTemp, char *currentWind, char *currentTime, char *currentWeather, char *currentWeatherAbbr)
{
    //Return if wifi isn't connected
    if (WiFi.status() != WL_CONNECTED)
        return;

    //Wake up WiFi if sleeping and save inital state
    bool sleep = WiFi.getSleep();
    WiFi.setSleep(false);

    //HTTP object used to make get request
    HTTPClient http;

    http.getStream().setNoDelay(true);
    http.getStream().setTimeout(1);

    //Add woeid to api call. woeid is API specific variable name used to set location
    char url[256];
    sprintf(url, "https://www.metaweather.com/api/location/%d/", location);

    //Initiate http
    http.begin(url);

    //Actually make HTTPS GET request
    int httpCode = http.GET();
    if (httpCode == 200)
    {
        int32_t len = http.getSize();

        if (len > 0)
        {
            //Try parsing JSON object
            DeserializationError error = deserializeJson(doc, http.getStream());

            //If an error happens print it to Serial monitor
            if (error)
            {
                Serial.print(F("deserializeJson() failed: "));
                Serial.println(error.c_str());
            }
            else
            {
                //Set all data got from internet using formatTemp and formatWind defined above
                //This part relies heavily on ArduinoJson library
                formatTemp(currentTemp, doc["consolidated_weather"][0][F("the_temp")].as<float>());
                formatWind(currentWind, doc["consolidated_weather"][0][F("wind_speed")].as<float>());

                strcpy(city, doc["title"].as<char *>());
                strcpy(currentWeather, doc["consolidated_weather"][0]["weather_state_name"].as<char *>());
                strcpy(currentWeatherAbbr, doc["consolidated_weather"][0]["weather_state_abbr"].as<char *>());

                formatTemp(temp1, doc["consolidated_weather"][0][F("the_temp")].as<float>());
                formatTemp(temp2, doc["consolidated_weather"][1][F("the_temp")].as<float>());
                formatTemp(temp3, doc["consolidated_weather"][2][F("the_temp")].as<float>());
                formatTemp(temp4, doc["consolidated_weather"][3][F("the_temp")].as<float>());
            }
        }
    }

    //Clear document and end http
    doc.clear();
    http.end();

    //Return to initial state
    WiFi.setSleep(sleep);
}

//Used to set correct time received from NTP server
void Network::setTime()
{
    //Used for setting correct time
    configTime(0, 0, "pool.ntp.org", "time.nist.gov");

    Serial.print(F("Waiting for NTP time sync: "));
    time_t nowSecs = time(nullptr);
    while (nowSecs < 8 * 3600 * 2)
    {
        // Print a dot every half a second while time is not set
        delay(500);
        Serial.print(F("."));
        yield();
        nowSecs = time(nullptr);
    }

    Serial.println();

    //Used to store time info
    struct tm timeinfo;
    gmtime_r(&nowSecs, &timeinfo);

    Serial.print(F("Current time: "));
    Serial.print(asctime(&timeinfo));
}

//From epoch received from NTP server, get day of the week
void Network::getDays(char *day, char *day1, char *day2, char *day3)
{
    // Seconds since 1.1.1970.
    time_t nowSecs = time(nullptr);

    //Find weekday

    //We get seconds since 1970, add 3600 (1 hour) times the time zone and add 3 to
    //make monday the first day of the week, as 1.1.1970. was a thursday
    //finally do mod 7 to insure our day is within [0, 6]
    int dayWeek = ((long)((nowSecs + 3600L * timeZone) / 86400L) + 3) % 7;

    // Copy day data to globals in main file
    strncpy(day, weekDays[dayWeek], 3);
    strncpy(day1, weekDays[(dayWeek + 1) % 7], 3);
    strncpy(day2, weekDays[(dayWeek + 2) % 7], 3);
    strncpy(day3, weekDays[(dayWeek + 3) % 7], 3);
}

//Make API query to receive city woeid - city identification specific to API
void Network::findCity(char *city)
{
    //If not connected to WiFi, return
    if (WiFi.status() != WL_CONNECTED)
        return;

    //Wake WiFi module and save initial state
    bool sleep = WiFi.getSleep();
    WiFi.setSleep(false);

    //HTTP object
    HTTPClient http;

    http.getStream().setNoDelay(true);
    http.getStream().setTimeout(1);

    //Add query parameter to URL
    char url[256];
    strcpy(url, "https://www.metaweather.com/api/location/search/?query=");
    strcat(url, city);

    //Initiate HTTP
    http.begin(url);

    //Make GET HTTP request
    int httpCode = http.GET();
    if (httpCode == 200) // 200: http success
    {
        int32_t len = http.getSize();

        if (len > 0)
        {
            //Try to parse JSON object
            DeserializationError error = deserializeJson(doc, http.getStream());

            //Print error to Serial monitor if one exists
            if (error)
            {
                Serial.print(F("deserializeJson() failed: "));
                Serial.println(error.c_str());
            }
            else
            {
                //Empty list means no matches for the city
                if (doc.size() == 0)
                {
                    Serial.println(F("City not found"));
                }
                else
                {
                    //woeid id used for fetching data later on
                    location = doc[0]["woeid"].as<int>();

                    Serial.println(F("Found city, woied:"));
                    Serial.println(location);
                }
            }
        }
    }

    //Clear document and end http
    doc.clear();
    http.end();

    //Return module to initial state
    WiFi.setSleep(sleep);
};