package term

import (
	"bytes"
	"syscall"
	"unsafe"
)

type winsize struct {
	Row    uint16
	Col    uint16
	Xpixel uint16
	Ypixel uint16
}

// HR returns a horizontal ruler of a given size
func HR(len int) string {
	h := bytes.Repeat([]byte("="), len)
	return string(h)
}

// GetTerminalWidth returns the current terminal width in symbols
func GetTerminalWidth() int {
	ws := &winsize{}
	retCode, _, errno := syscall.Syscall(syscall.SYS_IOCTL,
		uintptr(syscall.Stdin),
		uintptr(syscall.TIOCGWINSZ),
		uintptr(unsafe.Pointer(ws)))

	if int(retCode) == -1 {
		panic(errno)
	}
	return int(ws.Col)
}