/*-----------------------------------------------------------------------*/
/* Get current time for FatFS                                            */
/*-----------------------------------------------------------------------*/

#include "ff.h"
#include "pico/stdlib.h"
#include <string.h>

// Parse compilation date/time macros
static int get_month_from_string(const char* month_str) {
    const char* months[] = {"Jan", "Feb", "Mar", "Apr", "May", "Jun",
                           "Jul", "Aug", "Sep", "Oct", "Nov", "Dec"};
    for (int i = 0; i < 12; i++) {
        if (strncmp(month_str, months[i], 3) == 0) {
            return i + 1;
        }
    }
    return 1; // Default to January
}

/* Get current time */
DWORD get_fattime (void)
{
    // Use compilation date/time from __DATE__ and __TIME__ macros
    // __DATE__ format: "Jan 28 2026"
    // __TIME__ format: "HH:MM:SS"
    // Format: bit31:25=Year(0-127 +1980), bit24:21=Month(1-12), bit20:16=Day(1-31)
    //         bit15:11=Hour(0-23), bit10:5=Minute(0-59), bit4:0=Second/2(0-29)
    
    // Parse __DATE__ (e.g., "Jan 28 2026")
    char month_str[4] = {__DATE__[0], __DATE__[1], __DATE__[2], 0};
    int day = (__DATE__[4] == ' ' ? 0 : (__DATE__[4] - '0') * 10) + (__DATE__[5] - '0');
    int year = ((__DATE__[7] - '0') * 1000) + ((__DATE__[8] - '0') * 100) +
               ((__DATE__[9] - '0') * 10) + (__DATE__[10] - '0');
    int month = get_month_from_string(month_str);
    
    // Parse __TIME__ (e.g., "12:34:56")
    int hour = ((__TIME__[0] - '0') * 10) + (__TIME__[1] - '0');
    int minute = ((__TIME__[3] - '0') * 10) + (__TIME__[4] - '0');
    int second = ((__TIME__[6] - '0') * 10) + (__TIME__[7] - '0');
    
    return ((DWORD)(year - 1980) << 25)
         | ((DWORD)month << 21)
         | ((DWORD)day << 16)
         | ((DWORD)hour << 11)
         | ((DWORD)minute << 5)
         | ((DWORD)(second / 2));
}