module strings

// strings.repeat - fill a string with `n` repetitions of the character `c`
@[direct_array_access]
pub fn repeat(c u8, n int) string {
    if n <= 0 {
        return ''
    }
    mut bytes := unsafe { malloc_noscan(n + 1) }
    unsafe {
        C.memset(bytes, c, n)
        bytes[n] = 0
    }
    return unsafe { bytes.vstring_with_len(n) }
}

// strings.repeat_string - gives you `n` repetitions of the substring `s`
// Note: strings.repeat, that repeats a single byte, is between 2x
// and 24x faster than strings.repeat_string called for a 1 char string.
@[direct_array_access]
pub fn repeat_string(s string, n int) string {
    if n <= 0 || s.len == 0 {
        return ''
    }
    slen := s.len
    blen := slen * n
    mut bytes := unsafe { malloc_noscan(blen + 1) }
    for bi in 0 .. n {
        bislen := bi * slen
        for si in 0 .. slen {
            unsafe {
                bytes[bislen + si] = s[si]
            }
        }
    }
    unsafe {
        bytes[blen] = 0
    }
    return unsafe { bytes.vstring_with_len(blen) }
}