termui/events.go
2022-08-28 12:46:41 -04:00

212 lines
4.7 KiB
Go

// Copyright 2017 Zack Guo <zack.y.guo@gmail.com>. All rights reserved.
// Use of this source code is governed by a GPLv3 license that can
// be found in the LICENSE file.
package termui
import (
"fmt"
tb "github.com/nsf/termbox-go"
)
/*
List of events:
mouse events:
<MouseLeft> <MouseRight> <MouseMiddle>
<MouseWheelUp> <MouseWheelDown>
keyboard events:
any uppercase or lowercase letter like j or J
<C-d> etc
<M-d> etc
<Up> <Down> <Left> <Right>
<Insert> <Delete> <Home> <End> <Previous> <Next>
<Backspace> <Tab> <Enter> <Escape> <Space>
<C-<Space>> etc
terminal events:
<Resize>
keyboard events that do not work:
<C-->
<C-2> <C-~>
<C-h>
<C-i>
<C-m>
<C-[> <C-3>
<C-\\>
<C-]>
<C-/> <C-_>
<C-8>
*/
type EventType uint
const (
KeyboardEvent EventType = iota
MouseEvent
ResizeEvent
)
type Event struct {
Type EventType
ID string
Payload interface{}
}
// Mouse payload.
type Mouse struct {
Drag bool
X int
Y int
}
// Resize payload.
type Resize struct {
Width int
Height int
}
// PollEvents gets events from termbox, converts them, then sends them to each of its channels.
func PollEvents() <-chan Event {
ch := make(chan Event)
go func() {
for {
ch <- convertTermboxEvent(tb.PollEvent())
}
}()
return ch
}
var keyboardMap = map[tb.Key]string{
tb.KeyF1: "<F1>",
tb.KeyF2: "<F2>",
tb.KeyF3: "<F3>",
tb.KeyF4: "<F4>",
tb.KeyF5: "<F5>",
tb.KeyF6: "<F6>",
tb.KeyF7: "<F7>",
tb.KeyF8: "<F8>",
tb.KeyF9: "<F9>",
tb.KeyF10: "<F10>",
tb.KeyF11: "<F11>",
tb.KeyF12: "<F12>",
tb.KeyInsert: "<Insert>",
tb.KeyDelete: "<Delete>",
tb.KeyHome: "<Home>",
tb.KeyEnd: "<End>",
tb.KeyPgup: "<PageUp>",
tb.KeyPgdn: "<PageDown>",
tb.KeyArrowUp: "<Up>",
tb.KeyArrowDown: "<Down>",
tb.KeyArrowLeft: "<Left>",
tb.KeyArrowRight: "<Right>",
tb.KeyCtrlSpace: "<C-<Space>>", // tb.KeyCtrl2 tb.KeyCtrlTilde
tb.KeyCtrlA: "<C-a>",
tb.KeyCtrlB: "<C-b>",
tb.KeyCtrlC: "<C-c>",
tb.KeyCtrlD: "<C-d>",
tb.KeyCtrlE: "<C-e>",
tb.KeyCtrlF: "<C-f>",
tb.KeyCtrlG: "<C-g>",
tb.KeyBackspace: "<C-<Backspace>>", // tb.KeyCtrlH
tb.KeyTab: "<Tab>", // tb.KeyCtrlI
tb.KeyCtrlJ: "<C-j>",
tb.KeyCtrlK: "<C-k>",
tb.KeyCtrlL: "<C-l>",
tb.KeyEnter: "<Enter>", // tb.KeyCtrlM
tb.KeyCtrlN: "<C-n>",
tb.KeyCtrlO: "<C-o>",
tb.KeyCtrlP: "<C-p>",
tb.KeyCtrlQ: "<C-q>",
tb.KeyCtrlR: "<C-r>",
tb.KeyCtrlS: "<C-s>",
tb.KeyCtrlT: "<C-t>",
tb.KeyCtrlU: "<C-u>",
tb.KeyCtrlV: "<C-v>",
tb.KeyCtrlW: "<C-w>",
tb.KeyCtrlX: "<C-x>",
tb.KeyCtrlY: "<C-y>",
tb.KeyCtrlZ: "<C-z>",
tb.KeyEsc: "<Escape>", // tb.KeyCtrlLsqBracket tb.KeyCtrl3
tb.KeyCtrl4: "<C-4>", // tb.KeyCtrlBackslash
tb.KeyCtrl5: "<C-5>", // tb.KeyCtrlRsqBracket
tb.KeyCtrl6: "<C-6>",
tb.KeyCtrl7: "<C-7>", // tb.KeyCtrlSlash tb.KeyCtrlUnderscore
tb.KeySpace: "<Space>",
tb.KeyBackspace2: "<Backspace>", // tb.KeyCtrl8:
}
// convertTermboxKeyboardEvent converts a termbox keyboard event to a more friendly string format.
// Combines modifiers into the string instead of having them as additional fields in an event.
func convertTermboxKeyboardEvent(e tb.Event) Event {
ID := "%s"
if e.Mod == tb.ModAlt {
ID = "<M-%s>"
}
if e.Ch != 0 {
ID = fmt.Sprintf(ID, string(e.Ch))
} else {
converted, ok := keyboardMap[e.Key]
if !ok {
converted = ""
}
ID = fmt.Sprintf(ID, converted)
}
return Event{
Type: KeyboardEvent,
ID: ID,
}
}
var mouseButtonMap = map[tb.Key]string{
tb.MouseLeft: "<MouseLeft>",
tb.MouseMiddle: "<MouseMiddle>",
tb.MouseRight: "<MouseRight>",
tb.MouseRelease: "<MouseRelease>",
tb.MouseWheelUp: "<MouseWheelUp>",
tb.MouseWheelDown: "<MouseWheelDown>",
}
func convertTermboxMouseEvent(e tb.Event) Event {
converted, ok := mouseButtonMap[e.Key]
if !ok {
converted = "Unknown_Mouse_Button"
}
Drag := e.Mod == tb.ModMotion
return Event{
Type: MouseEvent,
ID: converted,
Payload: Mouse{
X: e.MouseX,
Y: e.MouseY,
Drag: Drag,
},
}
}
// convertTermboxEvent turns a termbox event into a termui event.
func convertTermboxEvent(e tb.Event) Event {
if e.Type == tb.EventError {
panic(e.Err)
}
switch e.Type {
case tb.EventKey:
return convertTermboxKeyboardEvent(e)
case tb.EventMouse:
return convertTermboxMouseEvent(e)
case tb.EventResize:
return Event{
Type: ResizeEvent,
ID: "<Resize>",
Payload: Resize{
Width: e.Width,
Height: e.Height,
},
}
}
return Event{}
}