// Copyright (c) 2026 Storm Dragon
// Authors: Storm Dragon, Angus Kola
// SPDX-License-Identifier: GPL-3.0-or-later

//go:build cgo

package datetime

/*
#include <locale.h>
#include <stdlib.h>
#include <time.h>
*/
import "C"

import (
	"time"
	"unsafe"
)

func init() {
	locale := C.CString("")
	defer C.free(unsafe.Pointer(locale))
	C.setlocale(C.LC_TIME, locale)
}

func format(now time.Time, spec string) string {
	cSpec := C.CString(spec)
	defer C.free(unsafe.Pointer(cSpec))
	tm := C.struct_tm{
		tm_year:  C.int(now.Year() - 1900),
		tm_mon:   C.int(int(now.Month()) - 1),
		tm_mday:  C.int(now.Day()),
		tm_hour:  C.int(now.Hour()),
		tm_min:   C.int(now.Minute()),
		tm_sec:   C.int(now.Second()),
		tm_wday:  C.int(int(now.Weekday())),
		tm_yday:  C.int(now.YearDay() - 1),
		tm_isdst: -1,
	}
	buffer := make([]C.char, 512)
	length := C.strftime(&buffer[0], C.size_t(len(buffer)), cSpec, &tm)
	return C.GoStringN(&buffer[0], C.int(length))
}