package char

import (
	"strings"
	"unicode"
)

// ----------------------------------------------------------------------------
// !Terminal Input Escape Code Sequences
// ----------------------------------------------------------------------------

const (
	Backspace   = '\x7f'
	Backslash   = '\\'
	Esc         = '\x1b'
	Enter       = '\r'
	SingleQuote = '\''
	DoubleQuote = '"'
)

// IsAscii Is this an ASCII character?
func IsAscii(char rune) bool {
	return char <= unicode.MaxASCII
}

// IsCtrl Is this an ASCII ctrl character?
func IsCtrl(char rune) bool {
	if !IsAscii(char) {
		return false
	}

	return char == 0x7f || char < 0x20
}

// Ctrl Return the input code of a Ctrl-key chord.
func Ctrl(char rune) rune {
	if !IsAscii(char) {
		return 0
	}

	ch := char & 0x1f

	return ch
}

// IsSeparator Is the character a general token separator type?
func IsSeparator(char rune) bool {
	return unicode.IsSpace(char) || strings.ContainsRune(",.()+-/*=~%<>[];", char)
}

// IsDigit is a simple wrapper around built-in unicode.IsDigit
func IsDigit(char rune) bool {
	return unicode.IsDigit(char)
}

// IsNumeric checks whether the character is a digit, or a numeric separator
func IsNumeric(char rune) bool {
	return IsDigit(char) || char == '.'
}