aboutsummaryrefslogtreecommitdiffstats
path: root/widgets/terminal.go
blob: 3a496deaffda87e4a769d5b97a2d322d996559fc (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
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
package widgets

import (
	"os/exec"
	"syscall"

	"git.sr.ht/~rjarry/aerc/lib/ui"
	"git.sr.ht/~rjarry/aerc/logging"
	tcellterm "git.sr.ht/~rockorager/tcell-term"

	"github.com/gdamore/tcell/v2"
	"github.com/gdamore/tcell/v2/views"
)

type Terminal struct {
	ui.Invalidatable
	closed      bool
	cmd         *exec.Cmd
	ctx         *ui.Context
	cursorShown bool
	destroyed   bool
	focus       bool
	vterm       *tcellterm.Terminal
	running     bool

	OnClose func(err error)
	OnEvent func(event tcell.Event) bool
	OnStart func()
	OnTitle func(title string)
}

func NewTerminal(cmd *exec.Cmd) (*Terminal, error) {
	term := &Terminal{
		cursorShown: true,
	}
	term.cmd = cmd
	term.vterm = tcellterm.New()
	return term, nil
}

func (term *Terminal) Close(err error) {
	if term.closed {
		return
	}
	// Stop receiving events
	term.vterm.Unwatch(term)
	if term.cmd != nil && term.cmd.Process != nil {
		err := term.cmd.Process.Kill()
		if err != nil {
			logging.Warnf("failed to kill process: %v", err)
		}
		// Race condition here, check if cmd exists. If process exits
		// fast, this could by nil and panic
		if term.cmd != nil {
			err = term.cmd.Wait()
		}
		if err != nil {
			logging.Warnf("failed for wait for process to terminate: %v", err)
		}
		term.cmd = nil
	}
	if term.vterm != nil {
		term.vterm.Close()
	}
	if !term.closed && term.OnClose != nil {
		term.OnClose(err)
	}
	term.ctx.HideCursor()
	term.closed = true
}

func (term *Terminal) Destroy() {
	if term.destroyed {
		return
	}
	if term.ctx != nil {
		term.ctx.HideCursor()
	}
	// If we destroy, we don't want to call the OnClose callback
	term.OnClose = nil
	term.Close(nil)
	term.vterm = nil
	term.destroyed = true
}

func (term *Terminal) Invalidate() {
	term.invalidate()
}

func (term *Terminal) invalidate() {
	term.DoInvalidate(term)
}

func (term *Terminal) Draw(ctx *ui.Context) {
	if term.destroyed {
		return
	}
	term.ctx = ctx // gross
	term.vterm.SetView(ctx.View())
	if !term.running && !term.closed && term.cmd != nil {
		go func() {
			defer logging.PanicHandler()
			term.vterm.Watch(term)
			attr := &syscall.SysProcAttr{Setsid: true, Setctty: true, Ctty: 1}
			if err := term.vterm.RunWithAttrs(term.cmd, attr); err != nil {
				logging.Errorf("error running terminal: %w", err)
				term.Close(err)
				term.running = false
				return
			}
			term.running = false
			term.Close(nil)
		}()
		for {
			if term.cmd.Process != nil {
				term.running = true
				break
			}
		}
		if term.OnStart != nil {
			term.OnStart()
		}
	}
	term.draw()
}

func (term *Terminal) draw() {
	term.vterm.Draw()
	if term.focus && !term.closed {
		if !term.cursorShown {
			term.ctx.HideCursor()
		} else {
			_, x, y, style := term.vterm.GetCursor()
			term.ctx.SetCursor(x, y)
			term.ctx.SetCursorStyle(style)
		}
	}
}

func (term *Terminal) MouseEvent(localX int, localY int, event tcell.Event) {
	if event, ok := event.(*tcell.EventMouse); ok {
		if term.OnEvent != nil {
			if term.OnEvent(event) {
				return
			}
		}
		if term.closed {
			return
		}
	}
}

func (term *Terminal) Focus(focus bool) {
	if term.closed {
		return
	}
	term.focus = focus
	if term.ctx != nil {
		if !term.focus {
			term.ctx.HideCursor()
		} else {
			_, x, y, style := term.vterm.GetCursor()
			term.ctx.SetCursor(x, y)
			term.ctx.SetCursorStyle(style)
			term.invalidate()
		}
	}
}

// HandleEvent is used to watch the underlying terminal events
func (term *Terminal) HandleEvent(ev tcell.Event) bool {
	if term.closed || term.destroyed {
		return false
	}
	switch ev := ev.(type) {
	case *views.EventWidgetContent:
		// Draw here for performance improvement. We call draw again in
		// the main Draw, but tcell-term only draws dirty cells, so it
		// won't be too much extra CPU there. Drawing there is needed
		// for certain msgviews, particularly if the pager command
		// exits.
		term.draw()
		// Perform a tcell screen.Show() to show our updates
		// immediately
		term.ctx.Show()
		term.invalidate()
		return true
	case *tcellterm.EventTitle:
		if term.OnTitle != nil {
			term.OnTitle(ev.Title())
		}
	}
	return false
}

func (term *Terminal) Event(event tcell.Event) bool {
	if term.OnEvent != nil {
		if term.OnEvent(event) {
			return true
		}
	}
	if term.closed {
		return false
	}
	return term.vterm.HandleEvent(event)
}