aboutsummaryrefslogtreecommitdiffstats
path: root/lib/ui/ui.go
blob: b65c06a4d3737dffb184c16e86e6a43f105a4496 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
package ui

import (
	"sync/atomic"

	"git.sr.ht/~rjarry/aerc/logging"
	"github.com/gdamore/tcell/v2"
)

type UI struct {
	Content DrawableInteractive
	exit    atomic.Value // bool
	ctx     *Context
	screen  tcell.Screen
	popover *Popover

	tcEvents chan tcell.Event
	invalid  int32 // access via atomic
}

func Initialize(content DrawableInteractive) (*UI, error) {

	screen, err := tcell.NewScreen()
	if err != nil {
		return nil, err
	}

	if err = screen.Init(); err != nil {
		return nil, err
	}

	screen.Clear()
	screen.HideCursor()

	width, height := screen.Size()

	state := UI{
		Content: content,
		screen:  screen,

		tcEvents: make(chan tcell.Event, 10),
	}
	state.ctx = NewContext(width, height, screen, state.onPopover)

	state.exit.Store(false)
	go func() {
		defer logging.PanicHandler()

		for !state.ShouldExit() {
			state.tcEvents <- screen.PollEvent()
		}
	}()

	state.invalid = 1
	content.OnInvalidate(func(_ Drawable) {
		atomic.StoreInt32(&state.invalid, 1)
	})
	if beeper, ok := content.(DrawableInteractiveBeeper); ok {
		beeper.OnBeep(screen.Beep)
	}
	content.Focus(true)

	if root, ok := content.(RootDrawable); ok {
		root.Initialize(&state)
	}

	return &state, nil
}

func (state *UI) onPopover(p *Popover) {
	state.popover = p
}

func (state *UI) ShouldExit() bool {
	return state.exit.Load().(bool)
}

func (state *UI) Exit() {
	state.exit.Store(true)
}

func (state *UI) Close() {
	state.screen.Fini()
}

func (state *UI) Tick() bool {
	more := false

	select {
	case event := <-state.tcEvents:
		switch event := event.(type) {
		case *tcell.EventResize:
			state.screen.Clear()
			width, height := event.Size()
			state.ctx = NewContext(width, height, state.screen, state.onPopover)
			state.Content.Invalidate()
		}
		// if we have a popover, and it can handle the event, it does so
		if state.popover == nil || !state.popover.Event(event) {
			// otherwise, we send the event to the main content
			state.Content.Event(event)
		}
		more = true
	default:
	}

	wasInvalid := atomic.SwapInt32(&state.invalid, 0)
	if wasInvalid != 0 {
		if state.popover != nil {
			// if the previous frame had a popover, rerender the entire display
			state.Content.Invalidate()
			atomic.StoreInt32(&state.invalid, 0)
		}
		// reset popover for the next Draw
		state.popover = nil
		state.Content.Draw(state.ctx)
		if state.popover != nil {
			// if the Draw resulted in a popover, draw it
			state.popover.Draw(state.ctx)
		}
		state.screen.Show()
		more = true
	}

	return more
}

func (state *UI) EnableMouse() {
	state.screen.EnableMouse()
}