v

1
// Copyright (c) 2019-2024 Alexander Medvednikov. All rights reserved.
2
// Use of this source code is governed by an MIT license
3
// that can be found in the LICENSE file.
4
//
5
// TODO: Mac version needs to be implemented
6
// Will serve as more advanced input method
7
// based on the work of https://github.com/AmokHuginnsson/replxx
8
//
9
module readline
10

11
import os
12

13
// termios definitions
14
// https://github.com/openbsd/src/blob/master/sys/sys/termios.h
15
// https://github.com/vocho/openqnx/blob/master/trunk/lib/c/public/termios.h
16
// https://github.com/omniti-labs/illumos-omnios/blob/master/usr/src/uts/common/sys/termios.h
17
// https://github.com/torvalds/linux/blob/master/include/uapi/asm-generic/termbits.h
18

19
struct Termios {
20
}
21

22
// Only use standard os.get_line
23
// Need implementation for readline capabilities
24
//
25
// read_line_utf8 blocks execution in a loop and awaits user input
26
// characters from a terminal until `EOF` or `Enter` key is encountered
27
// in the input stream.
28
// read_line_utf8 returns the complete input line as an UTF-8 encoded `[]rune` or
29
// an error if the line is empty.
30
// The `prompt` `string` is output as a prefix text for the input capturing.
31
// read_line_utf8 is the main method of the `readline` module and `Readline` struct.
32
pub fn (mut r Readline) read_line_utf8(prompt string) ![]rune {
33
	r.current = []rune{}
34
	r.cursor = 0
35
	r.prompt = prompt
36
	r.search_index = 0
37
	if r.previous_lines.len <= 1 {
38
		r.previous_lines << []rune{}
39
		r.previous_lines << []rune{}
40
	} else {
41
		r.previous_lines[0] = []rune{}
42
	}
43
	print(r.prompt)
44
	line := os.get_raw_line()
45
	if line.len >= 0 {
46
		r.current = line.runes()
47
	}
48
	r.previous_lines[0] = []rune{}
49
	r.search_index = 0
50
	if r.current.len == 0 {
51
		return error('empty line')
52
	}
53
	return r.current
54
}
55

56
// read_line does the same as `read_line_utf8` but returns user input as a `string`.
57
// (As opposed to `[]rune` returned by `read_line_utf8`).
58
pub fn (mut r Readline) read_line(prompt string) !string {
59
	s := r.read_line_utf8(prompt)!
60
	return s.string()
61
}
62

63
// read_line_utf8 blocks execution in a loop and awaits user input
64
// characters from a terminal until `EOF` or `Enter` key is encountered
65
// in the input stream.
66
// read_line_utf8 returns the complete input line as an UTF-8 encoded `[]rune` or
67
// an error if the line is empty.
68
// The `prompt` `string` is output as a prefix text for the input capturing.
69
// read_line_utf8 is the main method of the `readline` module and `Readline` struct.
70
// NOTE that this version of `read_line_utf8` is a standalone function without
71
// persistent functionalities (e.g. history).
72
pub fn read_line_utf8(prompt string) ![]rune {
73
	mut r := Readline{}
74
	s := r.read_line_utf8(prompt)!
75
	return s
76
}
77

78
// read_line does the same as `read_line_utf8` but returns user input as a `string`.
79
// (As opposed to `[]rune` as returned by `read_line_utf8`).
80
// NOTE that this version of `read_line` is a standalone function without
81
// persistent functionalities (e.g. history).
82
pub fn read_line(prompt string) !string {
83
	mut r := Readline{}
84
	s := r.read_line(prompt)!
85
	return s
86
}
87