forked from Mirrors/bubbletea
285 lines
7.1 KiB
Go
285 lines
7.1 KiB
Go
package tea
|
|
|
|
import (
|
|
"errors"
|
|
"fmt"
|
|
"io"
|
|
"unicode/utf8"
|
|
)
|
|
|
|
// KeyPressMsg contains information about a keypress
|
|
type KeyMsg Key
|
|
|
|
// String returns a friendly name for a key
|
|
func (k *KeyMsg) String() (str string) {
|
|
if k.Alt {
|
|
str += "alt+"
|
|
}
|
|
if k.Type == KeyRune {
|
|
str += string(k.Rune)
|
|
return str
|
|
} else if s, ok := keyNames[int(k.Type)]; ok {
|
|
str += s
|
|
return str
|
|
}
|
|
return ""
|
|
}
|
|
|
|
// IsRune returns weather or not the key is a rune
|
|
func (k *KeyMsg) IsRune() bool {
|
|
return k.Type == KeyRune
|
|
}
|
|
|
|
// Key contains information about a keypress
|
|
type Key struct {
|
|
Type KeyType
|
|
Rune rune
|
|
Alt bool
|
|
}
|
|
|
|
// KeyType indicates the key pressed
|
|
type KeyType int
|
|
|
|
// Control keys. I know we could do this with an iota, but the values are very
|
|
// specific, so we set the values explicitly to avoid any confusion.
|
|
//
|
|
// See also:
|
|
// https://en.wikipedia.org/wiki/C0_and_C1_control_codes
|
|
const (
|
|
keyNUL = 0 // null, \0
|
|
keySOH = 1 // start of heading
|
|
keySTX = 2 // start of text
|
|
keyETX = 3 // break, ctrl+c
|
|
keyEOT = 4 // end of transmission
|
|
keyENQ = 5 // enquiry
|
|
keyACK = 6 // acknowledge
|
|
keyBEL = 7 // bell, \a
|
|
keyBS = 8 // backspace
|
|
keyHT = 9 // horizontal tabulation, \t
|
|
keyLF = 10 // line feed, \n
|
|
keyVT = 11 // vertical tabulation \v
|
|
keyFF = 12 // form feed \f
|
|
keyCR = 13 // carriage return, \r
|
|
keySO = 14 // shift out
|
|
keySI = 15 // shift in
|
|
keyDLE = 16 // data link escape
|
|
keyDC1 = 17 // device control one
|
|
keyDC2 = 18 // device control two
|
|
keyDC3 = 19 // device control three
|
|
keyDC4 = 20 // device control four
|
|
keyNAK = 21 // negative acknowledge
|
|
keySYN = 22 // synchronous idle
|
|
keyETB = 23 // end of transmission block
|
|
keyCAN = 24 // cancel
|
|
keyEM = 25 // end of medium
|
|
keySUB = 26 // substitution
|
|
keyESC = 27 // escape, \e
|
|
keyFS = 28 // file separator
|
|
keyGS = 29 // group separator
|
|
keyRS = 30 // record separator
|
|
keyUS = 31 // unit separator
|
|
keySP = 32 // space
|
|
keyDEL = 127 // delete. on most systems this is mapped to backspace, I hear
|
|
)
|
|
|
|
// Aliases
|
|
const (
|
|
KeyNull = keyNUL
|
|
KeyBreak = keyETX
|
|
KeyEnter = keyCR
|
|
KeyBackspace = keyBS
|
|
KeyTab = keyHT
|
|
KeySpace = keySP
|
|
KeyEsc = keyESC
|
|
KeyEscape = keyESC
|
|
KeyDelete = keyDEL
|
|
|
|
KeyCtrlAt = keyNUL // ctrl+@
|
|
KeyCtrlA = keySOH
|
|
KeyCtrlB = keySTX
|
|
KeyCtrlC = keyETX
|
|
KeyCtrlD = keyEOT
|
|
KeyCtrlE = keyENQ
|
|
KeyCtrlF = keyACK
|
|
KeyCtrlG = keyBEL
|
|
KeyCtrlH = keyBS
|
|
KeyCtrlI = keyHT
|
|
KeyCtrlJ = keyLF
|
|
KeyCtrlK = keyVT
|
|
KeyCtrlL = keyFF
|
|
KeyCtrlM = keyCR
|
|
KeyCtrlN = keySO
|
|
KeyCtrlO = keySI
|
|
KeyCtrlP = keyDLE
|
|
KeyCtrlQ = keyDC1
|
|
KeyCtrlR = keyDC2
|
|
KeyCtrlS = keyDC3
|
|
KeyCtrlT = keyDC4
|
|
KeyCtrlU = keyNAK
|
|
KeyCtrlV = keyETB
|
|
KeyCtrlW = keyETB
|
|
KeyCtrlX = keyCAN
|
|
KeyCtrlY = keyEM
|
|
KeyCtrlZ = keySUB
|
|
KeyCtrlOpenBracket = keyESC // ctrl+[
|
|
KeyCtrlBackslash = keyFS // ctrl+\
|
|
KeyCtrlCloseBracket = keyGS // ctrl+]
|
|
KeyCtrlCaret = keyRS // ctrl+^
|
|
KeyCtrlUnderscore = keyUS // ctrl+_
|
|
KeyCtrlQuestionMark = keyDEL // ctrl+?
|
|
)
|
|
|
|
// Other keys we track
|
|
const (
|
|
KeyRune = -(iota + 1)
|
|
KeyUp
|
|
KeyDown
|
|
KeyRight
|
|
KeyLeft
|
|
KeyShiftTab
|
|
KeyHome
|
|
KeyEnd
|
|
KeyPgUp
|
|
KeyPgDown
|
|
)
|
|
|
|
// Mapping for control keys to friendly consts
|
|
var keyNames = map[int]string{
|
|
keyNUL: "ctrl+@", // also ctrl+`
|
|
keySOH: "ctrl+a",
|
|
keySTX: "ctrl+b",
|
|
keyETX: "ctrl+c",
|
|
keyEOT: "ctrl+d",
|
|
keyENQ: "ctrl+e",
|
|
keyACK: "ctrl+f",
|
|
keyBEL: "ctrl+g",
|
|
keyBS: "backspace", // also ctrl+h
|
|
keyHT: "tab", // also ctrl+i
|
|
keyLF: "ctrl+j",
|
|
keyVT: "ctrl+k",
|
|
keyFF: "ctrl+l",
|
|
keyCR: "enter",
|
|
keySO: "ctrl+n",
|
|
keySI: "ctrl+o",
|
|
keyDLE: "ctrl+p",
|
|
keyDC1: "ctrl+q",
|
|
keyDC2: "ctrl+r",
|
|
keyDC3: "ctrl+s",
|
|
keyDC4: "ctrl+t",
|
|
keyNAK: "ctrl+u",
|
|
keySYN: "ctrl+v",
|
|
keyETB: "ctrl+w",
|
|
keyCAN: "ctrl+x",
|
|
keyEM: "ctrl+y",
|
|
keySUB: "ctrl+z",
|
|
keyESC: "esc",
|
|
keyFS: "ctrl+\\",
|
|
keyGS: "ctrl+]",
|
|
keyRS: "ctrl+^",
|
|
keyUS: "ctrl+_",
|
|
keySP: "space",
|
|
keyDEL: "delete",
|
|
|
|
KeyRune: "rune",
|
|
KeyUp: "up",
|
|
KeyDown: "down",
|
|
KeyRight: "right",
|
|
KeyLeft: "left",
|
|
KeyShiftTab: "shift+tab",
|
|
KeyHome: "home",
|
|
KeyEnd: "end",
|
|
KeyPgUp: "pgup",
|
|
KeyPgDown: "pgdown",
|
|
}
|
|
|
|
// Mapping for sequences to consts
|
|
// TODO: should we just move this into the hex table?
|
|
var sequences = map[string]KeyType{
|
|
"\x1b[A": KeyUp,
|
|
"\x1b[B": KeyDown,
|
|
"\x1b[C": KeyRight,
|
|
"\x1b[D": KeyLeft,
|
|
}
|
|
|
|
// Mapping for hex codes to consts. Unclear why these won't register as
|
|
// sequences.
|
|
var hexes = map[string]Key{
|
|
"1b5b5a": Key{Type: KeyShiftTab},
|
|
"1b0d": Key{Type: KeyEnter, Alt: true},
|
|
"1b7f": Key{Type: KeyDelete, Alt: true},
|
|
"1b5b48": Key{Type: KeyHome},
|
|
"1b5b377e": Key{Type: KeyHome}, // urxvt
|
|
"1b5b313b3348": Key{Type: KeyHome, Alt: true},
|
|
"1b1b5b377e": Key{Type: KeyHome, Alt: true}, // ursvt
|
|
"1b5b46": Key{Type: KeyEnd},
|
|
"1b5b387e": Key{Type: KeyEnd}, // urxvt
|
|
"1b5b313b3346": Key{Type: KeyEnd, Alt: true},
|
|
"1b1b5b387e": Key{Type: KeyEnd, Alt: true}, // urxvt
|
|
"1b5b357e": Key{Type: KeyPgUp},
|
|
"1b5b353b337e": Key{Type: KeyPgUp, Alt: true},
|
|
"1b1b5b357e": Key{Type: KeyPgUp, Alt: true}, // urxvt
|
|
"1b5b367e": Key{Type: KeyPgDown},
|
|
"1b5b363b337e": Key{Type: KeyPgDown, Alt: true},
|
|
"1b1b5b367e": Key{Type: KeyPgDown, Alt: true}, // urxvt
|
|
"1b5b313b3341": Key{Type: KeyUp, Alt: true},
|
|
"1b5b313b3342": Key{Type: KeyDown, Alt: true},
|
|
"1b5b313b3343": Key{Type: KeyRight, Alt: true},
|
|
"1b5b313b3344": Key{Type: KeyLeft, Alt: true},
|
|
}
|
|
|
|
// ReadKey reads keypress input from a TTY and returns a string representation
|
|
// of a key
|
|
func ReadKey(r io.Reader) (Key, error) {
|
|
var buf [256]byte
|
|
|
|
// Read and block
|
|
numBytes, err := r.Read(buf[:])
|
|
if err != nil {
|
|
return Key{}, err
|
|
}
|
|
|
|
hex := fmt.Sprintf("%x", buf[:numBytes])
|
|
|
|
// Some of these need special handling
|
|
if k, ok := hexes[hex]; ok {
|
|
return k, nil
|
|
}
|
|
|
|
// Get unicode value
|
|
char, _ := utf8.DecodeRune(buf[:])
|
|
if char == utf8.RuneError {
|
|
return Key{}, errors.New("could not decode rune")
|
|
}
|
|
|
|
// Is it a control character?
|
|
if numBytes == 1 && char <= keyUS || char == keyDEL {
|
|
return Key{Type: KeyType(char)}, nil
|
|
}
|
|
|
|
// If it's a space treat it like a control character (otherwise it gets
|
|
// treated as the character " "
|
|
if string(char) == " " {
|
|
return Key{Type: KeyType(keySP)}, nil
|
|
}
|
|
|
|
// Is it a special sequence, like an arrow key?
|
|
if k, ok := sequences[string(buf[:numBytes])]; ok {
|
|
return Key{Type: k}, nil
|
|
}
|
|
|
|
// Is the alt key pressed? The buffer will be prefixed with an escape
|
|
// sequence if so
|
|
if numBytes > 1 && buf[0] == 0x1b {
|
|
// Now remove the initial escape sequence and re-process to get the
|
|
// character.
|
|
c, _ := utf8.DecodeRune(buf[1:])
|
|
if c == utf8.RuneError {
|
|
return Key{}, errors.New("could not decode rune after removing initial escape")
|
|
}
|
|
return Key{Alt: true, Type: KeyRune, Rune: c}, nil
|
|
}
|
|
|
|
// Just a regular, ol' rune
|
|
return Key{Type: KeyRune, Rune: char}, nil
|
|
}
|