Parse GPS String for Time and Coordinates

#include <stdio.h>
#include <string.h>

void parse_gprmc(char *nmea) {
    int str_idx = 0, field_idx = 0, field_ctr = 0;
    char delimiter = ',';
    char tokens[7][20] = {0};

    while(nmea[str_idx] != '\0') {
        if (nmea[str_idx] == delimiter) {
            tokens[field_ctr++][field_idx++] = '\0';
            field_idx = 0;
        } else {
            tokens[field_ctr][field_idx++] = nmea[str_idx];
        }

        str_idx++;
    }
    tokens[field_ctr++][field_idx++] = '\0';
    field_idx = 0;

    printf("Time: ", tokens[1]);
    int i = 0;
    for (i = 0; i<5; i++) {
        printf("%c", tokens[1][i]);
        if(i%2 != 0 && i > 0) {
            printf(":");
        }
    }
    printf("%c\n", tokens[1][i]);
    printf("Latitude: %s %s\n", tokens[3], tokens[4]);
    printf("Longitude: %s %s\n", tokens[5], tokens[6]);
}

int main() {
    char nmea[100];
    fgets(nmea, sizeof(nmea), stdin);
    parse_gprmc(nmea);
    return 0;
}