/*
    Code to run on 66s or 32s, despite platform differences, eg. time_t 4B on 32s, but 8B on 66s
    Need printf format string with variable type length specifier,
        to accomodate the same code on both platforms,
        so this ("%010lld %06ld micros\n",time_t,long)    // on esp8266
        must be ("%010ld %06ld micros\n",time_t,long)     // on esp32
    Build user function to leverage std::string functions: find, replace
        Needs to extend std::string.replace to 'replace all'

*/

#if defined (ARDUINO_ARCH_ESP8266)
#include <string>                          // support std::string on esp8266 (not req'd on esp32)
#include <ESP8266WiFi.h>
#endif

// https://stackoverflow.com/questions/3418231/replace-part-of-a-string-with-another-string
//  extend std::string.replace to 'replace all'
bool
replaceFirst (std::string &str, const std::string &from, const std::string &to, size_t start_pos = std::string::npos) {
    if (start_pos == std::string::npos)
        start_pos = str.find(from);
    if (start_pos == std::string::npos)     // not found
        return false;
    str.replace(start_pos, from.length(), to);
    return true;
}

// replace all occurences
int
replace (std::string &str, const std::string &from, const std::string &to) {
    size_t start_pos;
    uint16_t replaced = 0;
    while ((start_pos = str.find(from)) != std::string::npos) {
        replaceFirst (str, from, to, start_pos);
        replaced++;
    }
    return replaced;
}

std::string fmt_str ("%010lld %06ld 1st length specifier was for long long 64-bit var\n");        // var not literal so can modify if need be
time_t B4orB8   = 0x7ffffff;          // max signed 4 byte, promoted if on esp8266 to 8 byte
byte tt;        // sizeof time_t
long mikes      = 0xfff;


void setup()
{
    Serial.begin(115200);
    Serial.println();
    Serial.println(F(__FILE__ " ... compiled " __TIME__ "  " __DATE__));
    // Serial.println(LONG_LONG_MAX);

    tt = sizeof(time_t);
    Serial.println("Our format string that, depending on platform, may need a different length type/conversion specifier:");
    Serial.print(fmt_str.c_str());
    Serial.println();

    if (tt == 4)    // we need to change length specifier
    {
        Serial.printf("Detected %hu byte time_t, typical of esp32, 'lld' for 32-bit vars need 'ld'\n", tt);
        replace (fmt_str, "10lld", "10ld");
        Serial.println("Our 'replaced' format string now with 'ld' specifier(s):");
        Serial.print(fmt_str.c_str());
    }
    else if (tt == 8)
    {
        Serial.printf("format string not changed, 'lld' appropriate for %hu byte time_t, typical of esp8266\n", tt);
    }

    Serial.println();
    Serial.println("And the formatted string:");
    Serial.printf(fmt_str.c_str(), B4orB8, mikes);
    Serial.println();
}

void loop()
{
    delay(10); // this speeds up the simulation
}