#include <stdio.h>
#include <time.h>
#include <sys/time.h>
#include "driver/uart.h"

#define TXD  (1)
#define RXD  (3)
#define BUF_SIZE (1024)
const int uart_num = UART_NUM_1;

void setup()
{
    uart_config_t uart_config = {
        .baud_rate = 115200,
        .data_bits = UART_DATA_8_BITS,
        .parity = UART_PARITY_DISABLE,
        .stop_bits = UART_STOP_BITS_1,
        .flow_ctrl = UART_HW_FLOWCTRL_DISABLE,    
        .rx_flow_ctrl_thresh = 122,
    };

//Configure UART1 parameters
    uart_param_config(uart_num, &uart_config);

    //Set UART1 pins(TX: IO4, RX: I05)
    uart_set_pin(uart_num, TXD, RXD, UART_PIN_NO_CHANGE, UART_PIN_NO_CHANGE);
    
    //Install UART driver (we don't need an event queue here)
    //In this example we don't even use a buffer for sending data.
    uart_driver_install(uart_num, BUF_SIZE * 2, 0, 0, NULL, 0);


    setenv("TZ","ACST-8:30ACDT,M3.2.0/2:00:00,M11.1.0/2:00:00", 1);
    tzset();
}

void set_time_from_epoch()
{
    uint8_t* data = (uint8_t*) malloc(BUF_SIZE);

    time_t external_epoch = uart_read_bytes(uart_num, data, 0, 20);
    struct timeval tv = {
        .tv_sec = external_epoch,
        .tv_usec = 0
    };

    settimeofday(&tv, NULL);
}

void app_main(void)
{
    setup();
    set_time_from_epoch();

    // Optional: print to confirm
    time_t now = time(NULL);
    printf("System time is now: %s", ctime(&now));
}