summaryrefslogtreecommitdiff
path: root/widgets/compose.go
blob: 5f2c70692b5993626a07e362e075c192dc46235c (plain)
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
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
package widgets

import (
	"bufio"
	"bytes"
	"fmt"
	"io"
	"io/ioutil"
	"mime"
	"net/http"
	"net/textproto"
	"os"
	"os/exec"
	"path/filepath"
	"strings"
	"time"

	"github.com/ProtonMail/go-crypto/openpgp"
	"github.com/emersion/go-message/mail"
	"github.com/emersion/go-pgpmail"
	"github.com/gdamore/tcell/v2"
	"github.com/mattn/go-runewidth"
	"github.com/mitchellh/go-homedir"
	"github.com/pkg/errors"

	"git.sr.ht/~rjarry/aerc/completer"
	"git.sr.ht/~rjarry/aerc/config"
	"git.sr.ht/~rjarry/aerc/lib"
	"git.sr.ht/~rjarry/aerc/lib/format"
	"git.sr.ht/~rjarry/aerc/lib/templates"
	"git.sr.ht/~rjarry/aerc/lib/ui"
	"git.sr.ht/~rjarry/aerc/models"
	"git.sr.ht/~rjarry/aerc/worker/types"
)

type Composer struct {
	editors map[string]*headerEditor // indexes in lower case (from / cc / bcc)
	header  *mail.Header
	parent  models.OriginalMail // parent of current message, only set if reply

	acctConfig *config.AccountConfig
	config     *config.AercConfig
	acct       *AccountView
	aerc       *Aerc

	attachments []string
	editor      *Terminal
	email       *os.File
	grid        *ui.Grid
	heditors    *ui.Grid // from, to, cc display a user can jump to
	review      *reviewMessage
	worker      *types.Worker
	completer   *completer.Completer
	sign        bool
	encrypt     bool

	layout    HeaderLayout
	focusable []ui.MouseableDrawableInteractive
	focused   int
	sent      bool

	onClose []func(ti *Composer)

	width int
}

func NewComposer(aerc *Aerc, acct *AccountView, conf *config.AercConfig,
	acctConfig *config.AccountConfig, worker *types.Worker, template string,
	h *mail.Header, orig models.OriginalMail) (*Composer, error) {

	if h == nil {
		h = new(mail.Header)
	}
	if fl, err := h.AddressList("from"); err != nil || fl == nil {
		fl, err = mail.ParseAddressList(acctConfig.From)
		// realistically this blows up way before us during the config loading
		if err != nil {
			return nil, err
		}
		if fl != nil {
			h.SetAddressList("from", fl)

		}
	}

	templateData := templates.ParseTemplateData(h, orig)
	cmpl := completer.New(conf.Compose.AddressBookCmd, func(err error) {
		aerc.PushError(
			fmt.Sprintf("could not complete header: %v", err))
		worker.Logger.Printf("could not complete header: %v", err)
	}, aerc.Logger())

	email, err := ioutil.TempFile("", "aerc-compose-*.eml")
	if err != nil {
		// TODO: handle this better
		return nil, err
	}

	c := &Composer{
		acct:       acct,
		acctConfig: acctConfig,
		aerc:       aerc,
		config:     conf,
		header:     h,
		parent:     orig,
		email:      email,
		worker:     worker,
		// You have to backtab to get to "From", since you usually don't edit it
		focused:   1,
		completer: cmpl,
	}
	if err := c.AddTemplate(template, templateData); err != nil {
		return nil, err
	}
	c.buildComposeHeader(aerc, cmpl)

	c.AddSignature()

	c.updateGrid()
	c.ShowTerminal()

	return c, nil
}

func (c *Composer) buildComposeHeader(aerc *Aerc, cmpl *completer.Completer) {

	c.layout = aerc.conf.Compose.HeaderLayout
	c.editors = make(map[string]*headerEditor)
	c.focusable = make([]ui.MouseableDrawableInteractive, 0)
	uiConfig := aerc.SelectedAccountUiConfig()

	for i, row := range c.layout {
		for j, h := range row {
			h = strings.ToLower(h)
			c.layout[i][j] = h // normalize to lowercase
			e := newHeaderEditor(h, c.header, uiConfig)
			if aerc.conf.Ui.CompletionPopovers {
				e.input.TabComplete(cmpl.ForHeader(h), uiConfig.CompletionDelay)
			}
			c.editors[h] = e
			switch h {
			case "from":
				// Prepend From to support backtab
				c.focusable = append([]ui.MouseableDrawableInteractive{e}, c.focusable...)
			default:
				c.focusable = append(c.focusable, e)
			}
		}
	}

	// Add Cc/Bcc editors to layout if present in header and not already visible
	for _, h := range []string{"cc", "bcc"} {
		if c.header.Has(h) {
			if _, ok := c.editors[h]; !ok {
				e := newHeaderEditor(h, c.header, uiConfig)
				if aerc.conf.Ui.CompletionPopovers {
					e.input.TabComplete(cmpl.ForHeader(h), uiConfig.CompletionDelay)
				}
				c.editors[h] = e
				c.focusable = append(c.focusable, e)
				c.layout = append(c.layout, []string{h})
			}
		}
	}

	// load current header values into all editors
	for _, e := range c.editors {
		e.loadValue()
	}
}

func (c *Composer) SetSent() {
	c.sent = true
}

func (c *Composer) Sent() bool {
	return c.sent
}

func (c *Composer) SetSign(sign bool) *Composer {
	c.sign = sign
	return c
}

func (c *Composer) Sign() bool {
	return c.sign
}

func (c *Composer) SetEncrypt(encrypt bool) *Composer {
	c.encrypt = encrypt
	return c
}

func (c *Composer) Encrypt() bool {
	return c.encrypt
}

// Note: this does not reload the editor. You must call this before the first
// Draw() call.
func (c *Composer) SetContents(reader io.Reader) *Composer {
	c.email.Seek(0, io.SeekStart)
	io.Copy(c.email, reader)
	c.email.Sync()
	c.email.Seek(0, io.SeekStart)
	return c
}

func (c *Composer) AppendContents(reader io.Reader) {
	c.email.Seek(0, io.SeekEnd)
	io.Copy(c.email, reader)
	c.email.Sync()
}

func (c *Composer) AddTemplate(template string, data interface{}) error {
	if template == "" {
		return nil
	}

	templateText, err := templates.ParseTemplateFromFile(
		template, c.config.Templates.TemplateDirs, data)
	if err != nil {
		return err
	}

	mr, err := mail.CreateReader(templateText)
	if err != nil {
		return fmt.Errorf("Template loading failed: %v", err)
	}

	// copy the headers contained in the template to the compose headers
	hf := mr.Header.Fields()
	for hf.Next() {
		c.header.Set(hf.Key(), hf.Value())
	}

	part, err := mr.NextPart()
	if err != nil {
		return fmt.Errorf("Could not get body of template: %v", err)
	}

	c.AppendContents(part.Body)
	return nil
}

func (c *Composer) AddSignature() {
	var signature []byte
	if c.acctConfig.SignatureCmd != "" {
		var err error
		signature, err = c.readSignatureFromCmd()
		if err != nil {
			signature = c.readSignatureFromFile()
		}
	} else {
		signature = c.readSignatureFromFile()
	}
	c.AppendContents(bytes.NewReader(signature))
}

func (c *Composer) readSignatureFromCmd() ([]byte, error) {
	sigCmd := c.acctConfig.SignatureCmd
	cmd := exec.Command("sh", "-c", sigCmd)
	signature, err := cmd.Output()
	if err != nil {
		return nil, err
	}
	return signature, nil
}

func (c *Composer) readSignatureFromFile() []byte {
	sigFile := c.acctConfig.SignatureFile
	if sigFile == "" {
		return nil
	}
	sigFile, err := homedir.Expand(sigFile)
	if err != nil {
		return nil
	}
	signature, err := ioutil.ReadFile(sigFile)
	if err != nil {
		c.aerc.PushError(
			fmt.Sprintf(" Error loading signature from file: %v", sigFile))
		return nil
	}
	return signature
}

func (c *Composer) FocusTerminal() *Composer {
	if c.editor == nil {
		return c
	}
	c.focusable[c.focused].Focus(false)
	c.focused = len(c.editors)
	c.focusable[c.focused].Focus(true)
	return c
}

// OnHeaderChange registers an OnChange callback for the specified header.
func (c *Composer) OnHeaderChange(header string, fn func(subject string)) {
	if editor, ok := c.editors[strings.ToLower(header)]; ok {
		editor.OnChange(func() {
			fn(editor.input.String())
		})
	}
}

func (c *Composer) OnClose(fn func(composer *Composer)) {
	c.onClose = append(c.onClose, fn)
}

func (c *Composer) Draw(ctx *ui.Context) {
	c.width = ctx.Width()
	c.grid.Draw(ctx)
}

func (c *Composer) Invalidate() {
	c.grid.Invalidate()
}

func (c *Composer) OnInvalidate(fn func(d ui.Drawable)) {
	c.grid.OnInvalidate(func(_ ui.Drawable) {
		fn(c)
	})
}

func (c *Composer) Close() {
	for _, onClose := range c.onClose {
		onClose(c)
	}
	if c.email != nil {
		path := c.email.Name()
		c.email.Close()
		os.Remove(path)
		c.email = nil
	}
	if c.editor != nil {
		c.editor.Destroy()
		c.editor = nil
	}
}

func (c *Composer) Bindings() string {
	if c.editor == nil {
		return "compose::review"
	} else if c.editor == c.focusable[c.focused] {
		return "compose::editor"
	} else {
		return "compose"
	}
}

func (c *Composer) Event(event tcell.Event) bool {
	if c.editor != nil {
		return c.focusable[c.focused].Event(event)
	}
	return false
}

func (c *Composer) MouseEvent(localX int, localY int, event tcell.Event) {
	c.grid.MouseEvent(localX, localY, event)
	for _, e := range c.focusable {
		he, ok := e.(*headerEditor)
		if ok && he.focused {
			c.FocusEditor(he.name)
		}
	}
}

func (c *Composer) Focus(focus bool) {
	c.focusable[c.focused].Focus(focus)
}

func (c *Composer) Config() *config.AccountConfig {
	return c.acctConfig
}

func (c *Composer) Account() *AccountView {
	return c.acct
}

func (c *Composer) Worker() *types.Worker {
	return c.worker
}

//PrepareHeader finalizes the header, adding the value from the editors
func (c *Composer) PrepareHeader() (*mail.Header, error) {
	for _, editor := range c.editors {
		editor.storeValue()
	}

	// control headers not normally set by the user
	// repeated calls to PrepareHeader should be a noop
	if !c.header.Has("Message-Id") {
		err := c.header.GenerateMessageID()
		if err != nil {
			return nil, err
		}
	}
	if !c.header.Has("Date") {
		c.header.SetDate(time.Now())
	}
	return c.header, nil
}

func getSenderEmail(c *Composer) (string, error) {
	// add the from: field also to the 'recipients' list
	if c.acctConfig.From == "" {
		return "", errors.New("No 'From' configured for this account")
	}
	from, err := mail.ParseAddress(c.acctConfig.From)
	if err != nil {
		return "", errors.Wrap(err, "ParseAddress(config.From)")
	}
	return from.Address, nil
}

func getRecipientsEmail(c *Composer) ([]string, error) {
	h, err := c.PrepareHeader()
	if err != nil {
		return nil, errors.Wrap(err, "PrepareHeader")
	}

	// collect all 'recipients' from header (to:, cc:, bcc:)
	rcpts := make(map[string]bool)
	for _, key := range []string{"to", "cc", "bcc"} {
		list, err := h.AddressList(key)
		if err != nil {
			continue
		}
		for _, entry := range list {
			if entry != nil {
				rcpts[entry.Address] = true
			}
		}
	}

	// return email addresses as string slice
	results := []string{}
	for email, _ := range rcpts {
		results = append(results, email)
	}
	return results, nil
}

func (c *Composer) WriteMessage(header *mail.Header, writer io.Writer) error {
	if err := c.reloadEmail(); err != nil {
		return err
	}

	if c.sign || c.encrypt {

		var signedHeader mail.Header
		signedHeader.SetContentType("text/plain", nil)

		var buf bytes.Buffer
		var cleartext io.WriteCloser
		var err error

		var signer *openpgp.Entity
		if c.sign {
			signer, err = getSigner(c)
			if err != nil {
				return err
			}
		} else {
			signer = nil
		}

		if c.encrypt {
			var to []*openpgp.Entity
			rcpts, err := getRecipientsEmail(c)
			if err != nil {
				return err
			}
			for _, rcpt := range rcpts {
				toEntity, err := lib.GetEntityByEmail(rcpt)
				if err != nil {
					return errors.Wrap(err, "no key for "+rcpt)
				}
				to = append(to, toEntity)
			}
			cleartext, err = pgpmail.Encrypt(&buf, header.Header.Header,
				to, signer, nil)

			if err != nil {
				return err
			}
		} else {
			cleartext, err = pgpmail.Sign(&buf, header.Header.Header,
				signer, nil)
			if err != nil {
				return err
			}
		}

		err = writeMsgImpl(c, &signedHeader, cleartext)
		if err != nil {
			return err
		}
		cleartext.Close()
		io.Copy(writer, &buf)
		return nil

	} else {
		return writeMsgImpl(c, header, writer)
	}
}

func writeMsgImpl(c *Composer, header *mail.Header, writer io.Writer) error {
	if len(c.attachments) == 0 {
		// no attachements
		return writeInlineBody(header, c.email, writer)
	} else {
		// with attachements
		w, err := mail.CreateWriter(writer, *header)
		if err != nil {
			return errors.Wrap(err, "CreateWriter")
		}
		if err := writeMultipartBody(c.email, w); err != nil {
			return errors.Wrap(err, "writeMultipartBody")
		}
		for _, a := range c.attachments {
			if err := writeAttachment(a, w); err != nil {
				return errors.Wrap(err, "writeAttachment")
			}
		}
		w.Close()
	}
	return nil
}

func writeInlineBody(header *mail.Header, body io.Reader, writer io.Writer) error {
	header.SetContentType("text/plain", map[string]string{"charset": "UTF-8"})
	w, err := mail.CreateSingleInlineWriter(writer, *header)
	if err != nil {
		return errors.Wrap(err, "CreateSingleInlineWriter")
	}
	defer w.Close()
	if _, err := io.Copy(w, body); err != nil {
		return errors.Wrap(err, "io.Copy")
	}
	return nil
}

// write the message body to the multipart message
func writeMultipartBody(body io.Reader, w *mail.Writer) error {
	bh := mail.InlineHeader{}
	bh.SetContentType("text/plain", map[string]string{"charset": "UTF-8"})

	bi, err := w.CreateInline()
	if err != nil {
		return errors.Wrap(err, "CreateInline")
	}
	defer bi.Close()

	bw, err := bi.CreatePart(bh)
	if err != nil {
		return errors.Wrap(err, "CreatePart")
	}
	defer bw.Close()
	if _, err := io.Copy(bw, body); err != nil {
		return errors.Wrap(err, "io.Copy")
	}
	return nil
}

// write the attachment specified by path to the message
func writeAttachment(path string, writer *mail.Writer) error {
	f, err := os.Open(path)
	if err != nil {
		return errors.Wrap(err, "os.Open")
	}
	defer f.Close()

	reader := bufio.NewReader(f)

	// if we have an extension, prefer that instead of trying to sniff the header.
	// That's generally more accurate than sniffing as lots of things are zip files
	// under the hood, e.g. most office file types
	ext := filepath.Ext(path)
	var mimeString string
	if mimeString = mime.TypeByExtension(ext); mimeString != "" {
		// found it in the DB
	} else {
		// Sniff the mime type instead
		// http.DetectContentType only cares about the first 512 bytes
		head, err := reader.Peek(512)
		if err != nil && err != io.EOF {
			return errors.Wrap(err, "Peek")
		}
		mimeString = http.DetectContentType(head)
	}

	// mimeString can contain type and params (like text encoding),
	// so we need to break them apart before passing them to the headers
	mimeType, params, err := mime.ParseMediaType(mimeString)
	if err != nil {
		return errors.Wrap(err, "ParseMediaType")
	}
	filename := filepath.Base(path)
	params["name"] = filename

	// set header fields
	ah := mail.AttachmentHeader{}
	ah.SetContentType(mimeType, params)
	// setting the filename auto sets the content disposition
	ah.SetFilename(filename)

	aw, err := writer.CreateAttachment(ah)
	if err != nil {
		return errors.Wrap(err, "CreateAttachment")
	}
	defer aw.Close()

	if _, err := reader.WriteTo(aw); err != nil {
		return errors.Wrap(err, "reader.WriteTo")
	}

	return nil
}

func (c *Composer) GetAttachments() []string {
	return c.attachments
}

func (c *Composer) AddAttachment(path string) {
	c.attachments = append(c.attachments, path)
	c.resetReview()
}

func (c *Composer) DeleteAttachment(path string) error {
	for i, a := range c.attachments {
		if a == path {
			c.attachments = append(c.attachments[:i], c.attachments[i+1:]...)
			c.resetReview()
			return nil
		}
	}

	return errors.New("attachment does not exist")
}

func (c *Composer) resetReview() {
	if c.review != nil {
		c.grid.RemoveChild(c.review)
		c.review = newReviewMessage(c, nil)
		c.grid.AddChild(c.review).At(2, 0)
	}
}

func (c *Composer) termEvent(event tcell.Event) bool {
	switch event := event.(type) {
	case *tcell.EventMouse:
		switch event.Buttons() {
		case tcell.Button1:
			c.FocusTerminal()
			return true
		}
	}
	return false
}

func (c *Composer) termClosed(err error) {
	c.grid.RemoveChild(c.editor)
	c.review = newReviewMessage(c, err)
	c.grid.AddChild(c.review).At(2, 0)
	c.editor.Destroy()
	c.editor = nil
	c.focusable = c.focusable[:len(c.focusable)-1]
	if c.focused >= len(c.focusable) {
		c.focused = len(c.focusable) - 1
	}
}

func (c *Composer) ShowTerminal() {
	if c.editor != nil {
		return
	}
	if c.review != nil {
		c.grid.RemoveChild(c.review)
	}
	editorName := c.config.Compose.Editor
	if editorName == "" {
		editorName = os.Getenv("EDITOR")
	}
	if editorName == "" {
		editorName = "vi"
	}
	editor := exec.Command("/bin/sh", "-c", editorName+" "+c.email.Name())
	c.editor, _ = NewTerminal(editor) // TODO: handle error
	c.editor.OnEvent = c.termEvent
	c.editor.OnClose = c.termClosed
	c.grid.AddChild(c.editor).At(2, 0)
	c.focusable = append(c.focusable, c.editor)
}

func (c *Composer) PrevField() {
	c.focusable[c.focused].Focus(false)
	c.focused--
	if c.focused == -1 {
		c.focused = len(c.focusable) - 1
	}
	c.focusable[c.focused].Focus(true)
}

func (c *Composer) NextField() {
	c.focusable[c.focused].Focus(false)
	c.focused = (c.focused + 1) % len(c.focusable)
	c.focusable[c.focused].Focus(true)
}

func (c *Composer) FocusEditor(editor string) {
	editor = strings.ToLower(editor)
	c.focusable[c.focused].Focus(false)
	for i, f := range c.focusable {
		e := f.(*headerEditor)
		if strings.ToLower(e.name) == editor {
			c.focused = i
			break
		}
	}
	c.focusable[c.focused].Focus(true)
}

// AddEditor appends a new header editor to the compose window.
func (c *Composer) AddEditor(header string, value string, appendHeader bool) {
	var editor *headerEditor
	header = strings.ToLower(header)
	if e, ok := c.editors[header]; ok {
		e.storeValue() // flush modifications from the user to the header
		editor = e
	} else {
		uiConfig := c.aerc.SelectedAccountUiConfig()
		e := newHeaderEditor(header, c.header, uiConfig)
		if uiConfig.CompletionPopovers {
			e.input.TabComplete(c.completer.ForHeader(header), uiConfig.CompletionDelay)
		}
		c.editors[header] = e
		c.layout = append(c.layout, []string{header})
		// Insert focus of new editor before terminal editor
		c.focusable = append(
			c.focusable[:len(c.focusable)-1],
			e,
			c.focusable[len(c.focusable)-1],
		)
		editor = e
	}

	if appendHeader {
		currVal := editor.input.String()
		if currVal != "" {
			value = strings.TrimSpace(currVal) + ", " + value
		}
	}
	if value != "" || appendHeader {
		c.editors[header].input.Set(value)
		editor.storeValue()
	}
	if value == "" {
		c.FocusEditor(c.editors[header].name)
	}
	c.updateGrid()
}

// updateGrid should be called when the underlying header layout is changed.
func (c *Composer) updateGrid() {
	heditors, height := c.layout.grid(
		func(h string) ui.Drawable {
			return c.editors[h]
		},
	)

	if c.grid == nil {
		c.grid = ui.NewGrid().Columns([]ui.GridSpec{
			{Strategy: ui.SIZE_WEIGHT, Size: ui.Const(1)},
		})
	}

	c.grid.Rows([]ui.GridSpec{
		{Strategy: ui.SIZE_EXACT, Size: ui.Const(height)},
		{Strategy: ui.SIZE_EXACT, Size: ui.Const(1)},
		{Strategy: ui.SIZE_WEIGHT, Size: ui.Const(1)},
	})

	if c.heditors != nil {
		c.grid.RemoveChild(c.heditors)
	}
	borderStyle := c.config.Ui.GetStyle(config.STYLE_BORDER)
	borderChar := c.config.Ui.BorderCharHorizontal
	c.heditors = heditors
	c.grid.AddChild(c.heditors).At(0, 0)
	c.grid.AddChild(ui.NewFill(borderChar, borderStyle)).At(1, 0)
}

func (c *Composer) reloadEmail() error {
	name := c.email.Name()
	c.email.Close()
	file, err := os.Open(name)
	if err != nil {
		return errors.Wrap(err, "ReloadEmail")
	}
	c.email = file
	return nil
}

type headerEditor struct {
	name     string
	header   *mail.Header
	focused  bool
	input    *ui.TextInput
	uiConfig config.UIConfig
}

func newHeaderEditor(name string, h *mail.Header,
	uiConfig config.UIConfig) *headerEditor {
	he := &headerEditor{
		input:    ui.NewTextInput("", uiConfig),
		name:     name,
		header:   h,
		uiConfig: uiConfig,
	}
	he.loadValue()
	return he
}

//extractHumanHeaderValue extracts the human readable string for key from the
//header. If a parsing error occurs the raw value is returned
func extractHumanHeaderValue(key string, h *mail.Header) string {
	var val string
	var err error
	switch strings.ToLower(key) {
	case "to", "from", "cc", "bcc":
		var list []*mail.Address
		list, err = h.AddressList(key)
		val = format.FormatAddresses(list)
	default:
		val, err = h.Text(key)
	}
	if err != nil {
		// if we can't parse it, show it raw
		val = h.Get(key)
	}
	return val
}

//loadValue loads the value of he.name form the underlying header
//the value is decoded and meant for human consumption.
//decoding issues are ignored and return their raw values
func (he *headerEditor) loadValue() {
	he.input.Set(extractHumanHeaderValue(he.name, he.header))
	he.input.Invalidate()
}

//storeValue writes the current state back to the underlying header.
//errors are ignored
func (he *headerEditor) storeValue() {
	val := he.input.String()
	switch strings.ToLower(he.name) {
	case "to", "from", "cc", "bcc":
		list, err := mail.ParseAddressList(val)
		if err == nil {
			he.header.SetAddressList(he.name, list)
		} else {
			// garbage, but it'll blow up upon sending and the user can
			// fix the issue
			he.header.SetText(he.name, val)
		}
	default:
		he.header.SetText(he.name, val)
	}
}

//setValue overwrites the current value of the header editor and flushes it
//to the underlying header
func (he *headerEditor) setValue(val string) {
	he.input.Set(val)
	he.storeValue()
}

func (he *headerEditor) Draw(ctx *ui.Context) {
	name := textproto.CanonicalMIMEHeaderKey(he.name)
	// Extra character to put a blank cell between the header and the input
	size := runewidth.StringWidth(name+":") + 1
	defaultStyle := he.uiConfig.GetStyle(config.STYLE_DEFAULT)
	headerStyle := he.uiConfig.GetStyle(config.STYLE_HEADER)
	ctx.Fill(0, 0, size, ctx.Height(), ' ', defaultStyle)
	ctx.Printf(0, 0, headerStyle, "%s:", name)
	he.input.Draw(ctx.Subcontext(size, 0, ctx.Width()-size, 1))
}

func (he *headerEditor) MouseEvent(localX int, localY int, event tcell.Event) {
	switch event := event.(type) {
	case *tcell.EventMouse:
		switch event.Buttons() {
		case tcell.Button1:
			he.focused = true
		}

		width := runewidth.StringWidth(he.name + " ")
		if localX >= width {
			he.input.MouseEvent(localX-width, localY, event)
		}
	}
}

func (he *headerEditor) Invalidate() {
	he.input.Invalidate()
}

func (he *headerEditor) OnInvalidate(fn func(ui.Drawable)) {
	he.input.OnInvalidate(func(_ ui.Drawable) {
		fn(he)
	})
}

func (he *headerEditor) Focus(focused bool) {
	he.focused = focused
	he.input.Focus(focused)
}

func (he *headerEditor) Event(event tcell.Event) bool {
	return he.input.Event(event)
}

func (he *headerEditor) OnChange(fn func()) {
	he.input.OnChange(func(_ *ui.TextInput) {
		fn()
	})
}

type reviewMessage struct {
	composer *Composer
	grid     *ui.Grid
}

var reviewCommands = [][]string{
	{":send<enter>", "Send"},
	{":edit<enter>", "Edit"},
	{":attach<space>", "Add attachment"},
	{":detach<space>", "Remove attachment"},
	{":postpone<enter>", "Postpone"},
	{":abort<enter>", "Abort (discard message, no confirmation)"},
	{":choose -o d discard abort -o p postpone postpone<enter>", "Abort or postpone"},
}

func newReviewMessage(composer *Composer, err error) *reviewMessage {
	bindings := composer.config.MergeContextualBinds(
		composer.config.Bindings.ComposeReview,
		config.BIND_CONTEXT_ACCOUNT,
		composer.acctConfig.Name,
		"compose::review",
	)

	var actions []string

	for _, command := range reviewCommands {
		cmd := command[0]
		name := command[1]
		strokes, _ := config.ParseKeyStrokes(cmd)
		var inputs []string
		for _, input := range bindings.GetReverseBindings(strokes) {
			inputs = append(inputs, config.FormatKeyStrokes(input))
		}
		actions = append(actions, fmt.Sprintf("  %-6s  %-40s  %s",
			strings.Join(inputs[:], ", "), name, cmd))
	}

	spec := []ui.GridSpec{
		{Strategy: ui.SIZE_EXACT, Size: ui.Const(1)},
	}
	for i := 0; i < len(actions)-1; i++ {
		spec = append(spec, ui.GridSpec{Strategy: ui.SIZE_EXACT, Size: ui.Const(1)})
	}
	spec = append(spec, ui.GridSpec{Strategy: ui.SIZE_EXACT, Size: ui.Const(2)})
	spec = append(spec, ui.GridSpec{Strategy: ui.SIZE_EXACT, Size: ui.Const(1)})
	for i := 0; i < len(composer.attachments)-1; i++ {
		spec = append(spec, ui.GridSpec{Strategy: ui.SIZE_EXACT, Size: ui.Const(1)})
	}
	// make the last element fill remaining space
	spec = append(spec, ui.GridSpec{Strategy: ui.SIZE_WEIGHT, Size: ui.Const(1)})

	grid := ui.NewGrid().Rows(spec).Columns([]ui.GridSpec{
		{Strategy: ui.SIZE_WEIGHT, Size: ui.Const(1)},
	})

	uiConfig := composer.config.Ui

	if err != nil {
		grid.AddChild(ui.NewText(err.Error(), uiConfig.GetStyle(config.STYLE_ERROR)))
		grid.AddChild(ui.NewText("Press [q] to close this tab.",
			uiConfig.GetStyle(config.STYLE_DEFAULT))).At(1, 0)
	} else {
		grid.AddChild(ui.NewText("Send this email?",
			uiConfig.GetStyle(config.STYLE_TITLE))).At(0, 0)
		i := 1
		for _, action := range actions {
			grid.AddChild(ui.NewText(action,
				uiConfig.GetStyle(config.STYLE_DEFAULT))).At(i, 0)
			i += 1
		}
		grid.AddChild(ui.NewText("Attachments:",
			uiConfig.GetStyle(config.STYLE_TITLE))).At(i, 0)
		i += 1
		if len(composer.attachments) == 0 {
			grid.AddChild(ui.NewText("(none)",
				uiConfig.GetStyle(config.STYLE_DEFAULT))).At(i, 0)
		} else {
			for _, a := range composer.attachments {
				grid.AddChild(ui.NewText(a, uiConfig.GetStyle(config.STYLE_DEFAULT))).
					At(i, 0)
				i += 1
			}
		}
	}

	return &reviewMessage{
		composer: composer,
		grid:     grid,
	}
}

func (rm *reviewMessage) Invalidate() {
	rm.grid.Invalidate()
}

func (rm *reviewMessage) OnInvalidate(fn func(ui.Drawable)) {
	rm.grid.OnInvalidate(func(_ ui.Drawable) {
		fn(rm)
	})
}

func (rm *reviewMessage) Draw(ctx *ui.Context) {
	rm.grid.Draw(ctx)
}

func getSigner(c *Composer) (signer *openpgp.Entity, err error) {
	signerEmail, err := getSenderEmail(c)
	if err != nil {
		return nil, err
	}
	signer, err = lib.GetSignerEntityByEmail(signerEmail)
	if err != nil {
		return nil, err
	}

	key, ok := signer.SigningKey(time.Now())
	if !ok {
		return nil, fmt.Errorf("no signing key found for %s", signerEmail)
	}

	if !key.PrivateKey.Encrypted {
		return signer, nil
	}

	_, err = c.aerc.DecryptKeys([]openpgp.Key{key}, false)
	if err != nil {
		return nil, err
	}

	return signer, nil
}