term: reorganize the module

vlib/term/term.v

@@ -0,0 +1,48 @@
+module term
+
+import os
+
+const (
+	default_columns_size = 80
+	default_rows_size = 25
+)
+
+// 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 {
+	return if can_show_color_on_stdout() { green(s) } else { 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 {
+	return if can_show_color_on_stdout() { red(s) } else { s }
+}
+
+// h_divider returns a horizontal divider line with a dynamic width,
+// that depends on the current terminal settings.
+pub fn h_divider(divider string) string {
+	cols, _ := get_terminal_size()
+	result := divider.repeat(1 + (cols / divider.len))
+	return result[0..cols]
+}
+
+fn supports_escape_sequences(fd int) bool {
+	$if windows {
+		return (is_atty(fd) & 0x0004) > 0 && os.getenv('TERM') != 'dumb' // ENABLE_VIRTUAL_TERMINAL_PROCESSING
+	} $else {
+		return is_atty(fd) > 0 && os.getenv('TERM') != 'dumb'
+	}
+}