v/vlib/term/term.v

191 lines
4.8 KiB
V

module term
import os
import strings.textscanner
const (
default_columns_size = 80
default_rows_size = 25
)
// Coord - used by term.get_cursor_position and term.set_cursor_position
pub struct Coord {
pub mut:
x int
y int
}
// can_show_color_on_stdout returns true if colors are allowed in stdout;
// returns false otherwise.
pub fn can_show_color_on_stdout() bool {
return supports_escape_sequences(1)
}
// can_show_color_on_stderr returns true if colors are allowed in stderr;
// returns false otherwise.
pub fn can_show_color_on_stderr() bool {
return supports_escape_sequences(2)
}
// ok_message returns a colored string with green color.
// If colors are not allowed, returns a given string.
pub fn ok_message(s string) string {
if can_show_color_on_stdout() {
return green(' $s ')
}
return s
}
// fail_message returns a colored string with red color.
// If colors are not allowed, returns a given string.
pub fn fail_message(s string) string {
if can_show_color_on_stdout() {
return inverse(bg_white(bold(red(' $s '))))
}
return s
}
// warn_message returns a colored string with yellow color.
// If colors are not allowed, returns a given string.
pub fn warn_message(s string) string {
if can_show_color_on_stdout() {
return bright_yellow(' $s ')
}
return s
}
// colorize returns a colored string by running the specified `cfn` over
// the message `s`, only if colored output is supported by the terminal.
// Example: term.colorize(term.yellow, 'the message')
pub fn colorize(cfn fn (string) string, s string) string {
if can_show_color_on_stdout() {
return cfn(s)
}
return s
}
// strip_ansi removes any ANSI sequences in the `text`
pub fn strip_ansi(text string) string {
// This is a port of https://github.com/kilobyte/colorized-logs/blob/master/ansi2txt.c
// \e, [, 1, m, a, b, c, \e, [, 2, 2, m => abc
mut input := textscanner.new(text)
mut output := []byte{cap: text.len}
mut ch := 0
for ch != -1 {
ch = input.next()
if ch == 27 {
ch = input.next()
if ch == `[` {
for {
ch = input.next()
if ch in [`;`, `?`] || (ch >= `0` && ch <= `9`) {
continue
}
break
}
} else if ch == `]` {
ch = input.next()
if ch >= `0` && ch <= `9` {
for {
ch = input.next()
if ch == -1 || ch == 7 {
break
}
if ch == 27 {
ch = input.next()
break
}
}
}
} else if ch == `%` {
ch = input.next()
}
} else if ch != -1 {
output << byte(ch)
}
}
return output.bytestr()
}
// h_divider returns a horizontal divider line with a dynamic width,
// that depends on the current terminal settings.
// If an empty string is passed in, print enough spaces to make a new line
pub fn h_divider(divider string) string {
cols, _ := get_terminal_size()
mut result := ''
if divider.len > 0 {
result = divider.repeat(1 + (cols / divider.len))
} else {
result = ' '.repeat(1 + cols)
}
return result[0..cols]
}
// header_left returns a horizontal divider line with a title text on the left.
// e.g: term.header_left('TITLE', '=')
// ==== TITLE =========================
pub fn header_left(text string, divider string) string {
plain_text := strip_ansi(text)
xcols, _ := get_terminal_size()
cols := imax(1, xcols)
relement := if divider.len > 0 { divider } else { ' ' }
hstart := relement.repeat(4)[0..4]
remaining_cols := (cols - (hstart.len + 1 + plain_text.len + 1))
hend := relement.repeat((remaining_cols + 1) / relement.len)[0..remaining_cols]
return '$hstart $text $hend'
}
// header returns a horizontal divider line with a centered text in the middle.
// e.g: term.header('TEXT', '=')
// =============== TEXT ===============
pub fn header(text string, divider string) string {
if text.len == 0 {
return h_divider(divider)
}
xcols, _ := get_terminal_size()
cols := imax(1, xcols)
tlimit := imax(1, if cols > text.len + 2 + 2 * divider.len {
text.len
} else {
cols - 3 - 2 * divider.len
})
tlimit_alligned := if (tlimit % 2) != (cols % 2) { tlimit + 1 } else { tlimit }
tstart := imax(0, (cols - tlimit_alligned) / 2)
mut ln := ''
if divider.len > 0 {
ln = divider.repeat(1 + cols / divider.len)[0..cols]
} else {
ln = ' '.repeat(1 + cols)
}
if ln.len == 1 {
return ln + ' ' + text[0..tlimit] + ' ' + ln
}
return ln[0..tstart] + ' ' + text[0..tlimit] + ' ' + ln[tstart + tlimit + 2..cols]
}
fn imax(x int, y int) int {
return if x > y { x } else { y }
}
fn supports_escape_sequences(fd int) bool {
vcolors_override := os.getenv('VCOLORS')
if vcolors_override == 'always' {
return true
}
if vcolors_override == 'never' {
return false
}
if os.getenv('TERM') == 'dumb' {
return false
}
$if windows {
if os.getenv('ConEmuANSI') == 'ON' {
return true
}
// 4 is enable_virtual_terminal_processing
return (os.is_atty(fd) & 0x0004) > 0
} $else {
return os.is_atty(fd) > 0
}
}