summaryrefslogtreecommitdiff
path: root/internal/pipeline/pipeline.go
blob: cbd179b2f098806b8959f357245bce4b61bef481 (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
// Copyright 2020 Nick White.
// Use of this source code is governed by the GPLv3
// license that can be found in the LICENSE file.

// pipeline is a package used by the bookpipeline command, which
// handles the core functionality, using channels heavily to
// coordinate jobs. Note that it is considered an "internal" package,
// not intended for external use, and no guarantee is made of the
// stability of any interfaces provided.
package pipeline

import (
	"bytes"
	"context"
	"fmt"
	"io/ioutil"
	"log"
	"net/smtp"
	"os"
	"os/exec"
	"path/filepath"
	"regexp"
	"sort"
	"strings"
	"time"

	"rescribe.xyz/bookpipeline"
	"rescribe.xyz/preproc"
	"rescribe.xyz/utils/pkg/hocr"
)

const HeartbeatSeconds = 60

type Lister interface {
	ListObjects(bucket string, prefix string) ([]string, error)
	Log(v ...interface{})
	WIPStorageId() string
}

type Downloader interface {
	Download(bucket string, key string, fn string) error
	Log(v ...interface{})
	WIPStorageId() string
}

type DownloadLister interface {
	Download(bucket string, key string, fn string) error
	ListObjects(bucket string, prefix string) ([]string, error)
	Log(v ...interface{})
	WIPStorageId() string
}

type Uploader interface {
	Log(v ...interface{})
	Upload(bucket string, key string, path string) error
	WIPStorageId() string
}

type Queuer interface {
	AddToQueue(url string, msg string) error
	AnalyseQueueId() string
	CheckQueue(url string, timeout int64) (bookpipeline.Qmsg, error)
	DelFromQueue(url string, handle string) error
	Log(v ...interface{})
	OCRPageQueueId() string
	PreNoWipeQueueId() string
	PreQueueId() string
	QueueHeartbeat(msg bookpipeline.Qmsg, qurl string, duration int64) (bookpipeline.Qmsg, error)
	WipeQueueId() string
}

type UploadQueuer interface {
	Log(v ...interface{})
	Upload(bucket string, key string, path string) error
	WIPStorageId() string
	PreNoWipeQueueId() string
	PreQueueId() string
	WipeQueueId() string
	OCRPageQueueId() string
	AnalyseQueueId() string
	CheckQueue(url string, timeout int64) (bookpipeline.Qmsg, error)
	AddToQueue(url string, msg string) error
	DelFromQueue(url string, handle string) error
	QueueHeartbeat(msg bookpipeline.Qmsg, qurl string, duration int64) (bookpipeline.Qmsg, error)
}

type Pipeliner interface {
	AddToQueue(url string, msg string) error
	AnalyseQueueId() string
	CheckQueue(url string, timeout int64) (bookpipeline.Qmsg, error)
	DelFromQueue(url string, handle string) error
	Download(bucket string, key string, fn string) error
	GetLogger() *log.Logger
	Init() error
	ListObjects(bucket string, prefix string) ([]string, error)
	Log(v ...interface{})
	OCRPageQueueId() string
	PreNoWipeQueueId() string
	PreQueueId() string
	QueueHeartbeat(msg bookpipeline.Qmsg, qurl string, duration int64) (bookpipeline.Qmsg, error)
	Upload(bucket string, key string, path string) error
	WipeQueueId() string
	WIPStorageId() string
}

type MinPipeliner interface {
	Pipeliner
	MinimalInit() error
}

type pageimg struct {
	hocr, img string
}

type mailSettings struct {
	server, port, user, pass, from, to string
}

func GetMailSettings() (mailSettings, error) {
	p := filepath.Join(os.Getenv("HOME"), ".config", "bookpipeline", "mailsettings")
	b, err := ioutil.ReadFile(p)
	if err != nil {
		return mailSettings{}, fmt.Errorf("Error reading mailsettings from %s: %v", p, err)
	}
	f := strings.Fields(string(b))
	if len(f) != 6 {
		return mailSettings{}, fmt.Errorf("Error parsing mailsettings, need %d fields, got %d", 6, len(f))
	}
	return mailSettings{f[0], f[1], f[2], f[3], f[4], f[5]}, nil
}

// download reads file names from a channel and downloads them into
// dir, putting each successfully downloaded file name into the
// process channel. If an error occurs it is sent to the errc channel
// and the function returns early.
func download(ctx context.Context, dl chan string, process chan string, conn Downloader, dir string, errc chan error, logger *log.Logger) {
	for key := range dl {
		select {
		case <-ctx.Done():
			for range dl {
			} // consume the rest of the receiving channel so it isn't blocked
			errc <- ctx.Err()
			close(process)
			return
		default:
		}
		fn := filepath.Join(dir, filepath.Base(key))
		logger.Println("Downloading", key)
		err := conn.Download(conn.WIPStorageId(), key, fn)
		if err != nil {
			for range dl {
			} // consume the rest of the receiving channel so it isn't blocked
			errc <- err
			close(process)
			return
		}
		process <- fn
	}
	close(process)
}

// up reads file names from a channel and uploads them with
// the bookname/ prefix, removing the local copy of each file
// once it has been successfully uploaded. The done channel is
// then written to to signal completion. If an error occurs it
// is sent to the errc channel and the function returns early.
func up(ctx context.Context, c chan string, done chan bool, conn Uploader, bookname string, errc chan error, logger *log.Logger) {
	for path := range c {
		select {
		case <-ctx.Done():
			for range c {
			} // consume the rest of the receiving channel so it isn't blocked
			errc <- ctx.Err()
			return
		default:
		}
		name := filepath.Base(path)
		key := bookname + "/" + name
		logger.Println("Uploading", key)
		err := conn.Upload(conn.WIPStorageId(), key, path)
		if err != nil {
			for range c {
			} // consume the rest of the receiving channel so it isn't blocked
			errc <- err
			return
		}
		err = os.Remove(path)
		if err != nil {
			for range c {
			} // consume the rest of the receiving channel so it isn't blocked
			errc <- err
			return
		}
	}

	done <- true
}

// upAndQueue reads file names from a channel and uploads them with
// the bookname/ prefix, removing the local copy of each file
// once it has been successfully uploaded. Each done file name is
// added to the toQueue once it has been uploaded. The done channel
// is then written to to signal completion. If an error occurs it
// is sent to the errc channel and the function returns early.
func upAndQueue(ctx context.Context, c chan string, done chan bool, toQueue string, conn UploadQueuer, bookname string, training string, errc chan error, logger *log.Logger) {
	for path := range c {
		select {
		case <-ctx.Done():
			for range c {
			} // consume the rest of the receiving channel so it isn't blocked
			errc <- ctx.Err()
			return
		default:
		}
		name := filepath.Base(path)
		key := bookname + "/" + name
		logger.Println("Uploading", key)
		err := conn.Upload(conn.WIPStorageId(), key, path)
		if err != nil {
			for range c {
			} // consume the rest of the receiving channel so it isn't blocked
			errc <- err
			return
		}
		err = os.Remove(path)
		if err != nil {
			for range c {
			} // consume the rest of the receiving channel so it isn't blocked
			errc <- err
			return
		}
		logger.Println("Adding", key, training, "to queue", toQueue)
		err = conn.AddToQueue(toQueue, key+" "+training)
		if err != nil {
			for range c {
			} // consume the rest of the receiving channel so it isn't blocked
			errc <- err
			return
		}
	}

	done <- true
}

func Preprocess(thresholds []float64, nowipe bool) func(context.Context, chan string, chan string, chan error, *log.Logger) {
	return func(ctx context.Context, pre chan string, up chan string, errc chan error, logger *log.Logger) {
		for path := range pre {
			select {
			case <-ctx.Done():
				for range pre {
				} // consume the rest of the receiving channel so it isn't blocked
				errc <- ctx.Err()
				return
			default:
			}
			logger.Println("Preprocessing", path)
			done, err := preproc.PreProcMulti(path, thresholds, "binary", 0, !nowipe, 5, 30, 120, 30)
			if err != nil {
				for range pre {
				} // consume the rest of the receiving channel so it isn't blocked
				errc <- err
				return
			}
			_ = os.Remove(path)
			for _, p := range done {
				up <- p
			}
		}
		close(up)
	}
}

func Wipe(ctx context.Context, towipe chan string, up chan string, errc chan error, logger *log.Logger) {
	for path := range towipe {
		select {
		case <-ctx.Done():
			for range towipe {
			} // consume the rest of the receiving channel so it isn't blocked
			errc <- ctx.Err()
			return
		default:
		}
		logger.Println("Wiping", path)
		s := strings.Split(path, ".")
		base := strings.Join(s[:len(s)-1], "")
		outpath := base + "_bin0.0.png"
		err := preproc.WipeFile(path, outpath, 5, 0.03, 30, 120, 0.005, 30)
		if err != nil {
			for range towipe {
			} // consume the rest of the receiving channel so it isn't blocked
			errc <- err
			return
		}
		up <- outpath
	}
	close(up)
}

func Ocr(training string, tesscmd string) func(context.Context, chan string, chan string, chan error, *log.Logger) {
	return func(ctx context.Context, toocr chan string, up chan string, errc chan error, logger *log.Logger) {
		if tesscmd == "" {
			tesscmd = "tesseract"
		}
		for path := range toocr {
			select {
			case <-ctx.Done():
				for range toocr {
				} // consume the rest of the receiving channel so it isn't blocked
				errc <- ctx.Err()
				return
			default:
			}
			logger.Println("OCRing", path)
			name := strings.Replace(path, ".png", "", 1)
			cmd := exec.Command(tesscmd, "-l", training, path, name, "-c", "tessedit_create_hocr=1", "-c", "hocr_font_info=0")
			HideCmd(cmd)
			var stdout, stderr bytes.Buffer
			cmd.Stdout = &stdout
			cmd.Stderr = &stderr
			err := cmd.Run()
			if err != nil {
				for range toocr {
				} // consume the rest of the receiving channel so it isn't blocked
				errc <- fmt.Errorf("Error ocring %s with training %s: %s\nStdout: %s\nStderr: %s\n", path, training, err, stdout.String(), stderr.String())
				return
			}
			up <- name + ".hocr"
		}
		close(up)
	}
}

func Analyse(conn Downloader) func(context.Context, chan string, chan string, chan error, *log.Logger) {
	return func(ctx context.Context, toanalyse chan string, up chan string, errc chan error, logger *log.Logger) {
		confs := make(map[string][]*bookpipeline.Conf)
		bestconfs := make(map[string]*bookpipeline.Conf)
		savedir := ""

		for path := range toanalyse {
			select {
			case <-ctx.Done():
				for range toanalyse {
				} // consume the rest of the receiving channel so it isn't blocked
				errc <- ctx.Err()
				return
			default:
			}
			if savedir == "" {
				savedir = filepath.Dir(path)
			}
			logger.Println("Calculating confidence for", path)
			avg, err := hocr.GetAvgConf(path)
			if err != nil && err.Error() == "No words found" {
				continue
			}
			if err != nil {
				for range toanalyse {
				} // consume the rest of the receiving channel so it isn't blocked
				errc <- fmt.Errorf("Error retreiving confidence for %s: %s", path, err)
				return
			}
			base := filepath.Base(path)
			codestart := strings.Index(base, "_bin")
			name := base[0:codestart]
			var c bookpipeline.Conf
			c.Path = path
			c.Code = base[codestart:]
			c.Conf = avg
			confs[name] = append(confs[name], &c)
		}

		fn := filepath.Join(savedir, "conf")
		logger.Println("Saving confidences in file", fn)
		f, err := os.Create(fn)
		if err != nil {
			errc <- fmt.Errorf("Error creating file %s: %s", fn, err)
			return
		}
		defer f.Close()

		select {
		case <-ctx.Done():
			errc <- ctx.Err()
			return
		default:
		}

		logger.Println("Finding best confidence for each page, and saving all confidences")
		for base, conf := range confs {
			var best float64
			for _, c := range conf {
				if c.Conf > best {
					best = c.Conf
					bestconfs[base] = c
				}
				_, err = fmt.Fprintf(f, "%s\t%02.f\n", c.Path, c.Conf)
				if err != nil {
					errc <- fmt.Errorf("Error writing confidences file: %s", err)
					return
				}
			}
		}
		f.Close()
		up <- fn

		select {
		case <-ctx.Done():
			errc <- ctx.Err()
			return
		default:
		}

		logger.Println("Creating best file listing the best file for each page")
		fn = filepath.Join(savedir, "best")
		f, err = os.Create(fn)
		if err != nil {
			errc <- fmt.Errorf("Error creating file %s: %s", fn, err)
			return
		}
		defer f.Close()
		for _, conf := range bestconfs {
			_, err = fmt.Fprintf(f, "%s\n", filepath.Base(conf.Path))
		}
		f.Close()
		up <- fn

		var pgs []string
		for _, conf := range bestconfs {
			pgs = append(pgs, conf.Path)
		}
		sort.Strings(pgs)

		select {
		case <-ctx.Done():
			errc <- ctx.Err()
			return
		default:
		}

		logger.Println("Downloading binarised and original images to create PDFs")
		bookname, err := filepath.Rel(os.TempDir(), savedir)
		if err != nil {
			errc <- fmt.Errorf("Failed to do filepath.Rel of %s to %s: %s", os.TempDir(), savedir, err)
			return
		}
		colourpdf := new(bookpipeline.Fpdf)
		err = colourpdf.Setup()
		if err != nil {
			errc <- fmt.Errorf("Failed to set up PDF: %s", err)
			return
		}
		binarisedpdf := new(bookpipeline.Fpdf)
		err = binarisedpdf.Setup()
		if err != nil {
			errc <- fmt.Errorf("Failed to set up PDF: %s", err)
			return
		}
		fullsizepdf := new(bookpipeline.Fpdf)
		err = fullsizepdf.Setup()
		if err != nil {
			errc <- fmt.Errorf("Failed to set up PDF: %s", err)
			return
		}
		binhascontent, colourhascontent := false, false

		select {
		case <-ctx.Done():
			errc <- ctx.Err()
			return
		default:
		}

		var colourimgs, binimgs []pageimg

		for _, pg := range pgs {
			base := filepath.Base(pg)
			nosuffix := strings.TrimSuffix(base, ".hocr")
			p := strings.SplitN(base, "_bin", 2)

			var fn string
			if len(p) > 1 {
				fn = p[0] + ".jpg"
			} else {
				fn = nosuffix + ".jpg"
			}

			binimgs = append(binimgs, pageimg{hocr: base, img: nosuffix + ".png"})
			colourimgs = append(colourimgs, pageimg{hocr: base, img: fn})
		}

		for _, pg := range binimgs {
			select {
			case <-ctx.Done():
				errc <- ctx.Err()
				return
			default:
			}

			logger.Println("Downloading binarised page to add to PDF", pg.img)
			err := conn.Download(conn.WIPStorageId(), bookname+"/"+pg.img, filepath.Join(savedir, pg.img))
			if err != nil {
				logger.Println("Download failed; skipping page", pg.img)
			} else {
				err = binarisedpdf.AddPage(filepath.Join(savedir, pg.img), filepath.Join(savedir, pg.hocr), true)
				if err != nil {
					errc <- fmt.Errorf("Failed to add page %s to PDF: %s", pg.img, err)
					return
				}
				binhascontent = true
				err = os.Remove(filepath.Join(savedir, pg.img))
				if err != nil {
					errc <- err
					return
				}
			}
		}

		select {
		case <-ctx.Done():
			errc <- ctx.Err()
			return
		default:
		}

		if binhascontent {
			fn = filepath.Join(savedir, bookname+".binarised.pdf")
			err = binarisedpdf.Save(fn)
			if err != nil {
				errc <- fmt.Errorf("Failed to save binarised pdf: %s", err)
				return
			}
			up <- fn
		}

		for _, pg := range colourimgs {
			select {
			case <-ctx.Done():
				errc <- ctx.Err()
				return
			default:
			}

			logger.Println("Downloading colour page to add to PDF", pg.img)
			colourfn := pg.img
			err = conn.Download(conn.WIPStorageId(), bookname+"/"+colourfn, filepath.Join(savedir, colourfn))
			if err != nil {
				colourfn = strings.Replace(pg.img, ".jpg", ".png", 1)
				logger.Println("Download failed; trying", colourfn)
				err = conn.Download(conn.WIPStorageId(), bookname+"/"+colourfn, filepath.Join(savedir, colourfn))
				if err != nil {
					logger.Println("Download failed; skipping page", pg.img)
				}
			}
			if err == nil {
				err = colourpdf.AddPage(filepath.Join(savedir, colourfn), filepath.Join(savedir, pg.hocr), true)
				if err != nil {
					errc <- fmt.Errorf("Failed to add page %s to PDF: %s", pg.img, err)
					return
				}
				err = fullsizepdf.AddPage(filepath.Join(savedir, colourfn), filepath.Join(savedir, pg.hocr), false)
				if err != nil {
					errc <- fmt.Errorf("Failed to add page %s to PDF: %s", pg.img, err)
					return
				}
				colourhascontent = true
				err = os.Remove(filepath.Join(savedir, colourfn))
				if err != nil {
					errc <- err
					return
				}
			}
		}

		select {
		case <-ctx.Done():
			errc <- ctx.Err()
			return
		default:
		}

		if colourhascontent {
			fn = filepath.Join(savedir, bookname+".colour.pdf")
			err = colourpdf.Save(fn)
			if err != nil {
				errc <- fmt.Errorf("Failed to save colour pdf: %s", err)
				return
			}
			up <- fn

			fn = filepath.Join(savedir, bookname+".original.pdf")
			err = fullsizepdf.Save(fn)
			if err != nil {
				errc <- fmt.Errorf("Failed to save full size pdf: %s", err)
				return
			}
			up <- fn
		}

		select {
		case <-ctx.Done():
			errc <- ctx.Err()
			return
		default:
		}

		logger.Println("Creating graph")
		fn = filepath.Join(savedir, "graph.png")
		f, err = os.Create(fn)
		if err != nil {
			errc <- fmt.Errorf("Error creating file %s: %s", fn, err)
			return
		}
		defer f.Close()
		err = bookpipeline.Graph(bestconfs, filepath.Base(savedir), f)
		if err != nil {
			_ = os.Remove(fn)
		}
		if err != nil && err.Error() != "Not enough valid confidences" {
			errc <- fmt.Errorf("Error rendering graph: %s", err)
			return
		}

		select {
		case <-ctx.Done():
			errc <- ctx.Err()
			return
		default:
		}

		if err == nil {
			up <- fn
		}

		close(up)
	}
}

func heartbeat(conn Queuer, t *time.Ticker, msg bookpipeline.Qmsg, queue string, msgc chan bookpipeline.Qmsg, errc chan error) {
	currentmsg := msg
	for range t.C {
		m, err := conn.QueueHeartbeat(currentmsg, queue, HeartbeatSeconds*2)
		if err != nil {
			// This is for better debugging of the heartbeat issue
			conn.Log("Error with heartbeat", err)
			os.Exit(1)
			// TODO: would be better to ensure this error stops any running
			//       processes, as they will ultimately fail in the case of
			//       it. could do this by setting a global variable that
			//       processes check each time they loop.
			errc <- err
			t.Stop()
			return
		}
		if m.Id != "" {
			conn.Log("Replaced message handle as visibilitytimeout limit was reached")
			currentmsg = m
			// TODO: maybe handle communicating new msg more gracefully than this
			for range msgc {
			} // throw away any old msgc
			msgc <- m
		}
	}
}

// allOCRed checks whether all pages of a book have been OCRed.
// This is determined by whether every _bin0.?.png file has a
// corresponding .hocr file.
func allOCRed(bookname string, conn Lister) bool {
	objs, err := conn.ListObjects(conn.WIPStorageId(), bookname)
	if err != nil {
		return false
	}

	preprocessedPattern := regexp.MustCompile(`_bin[0-9].[0-9].png$`)

	atleastone := false
	for _, png := range objs {
		if preprocessedPattern.MatchString(png) {
			atleastone = true
			found := false
			hocrname := strings.TrimSuffix(png, ".png") + ".hocr"
			for _, hocr := range objs {
				if hocr == hocrname {
					found = true
					break
				}
			}
			if found == false {
				return false
			}
		}
	}
	if atleastone == false {
		return false
	}
	return true
}

// OcrPage OCRs a page based on a message. It may make sense to
// roll this back into processBook (on which it is based) once
// working well.
func OcrPage(ctx context.Context, msg bookpipeline.Qmsg, conn Pipeliner, process func(context.Context, chan string, chan string, chan error, *log.Logger), fromQueue string, toQueue string) error {
	dl := make(chan string)
	msgc := make(chan bookpipeline.Qmsg)
	processc := make(chan string)
	upc := make(chan string)
	done := make(chan bool)
	errc := make(chan error)

	msgparts := strings.Split(msg.Body, " ")
	bookname := filepath.Dir(msgparts[0])
	if len(msgparts) > 1 && msgparts[1] != "" {
		process = Ocr(msgparts[1], "")
	}

	d := filepath.Join(os.TempDir(), bookname)
	err := os.MkdirAll(d, 0755)
	if err != nil {
		return fmt.Errorf("Failed to create directory %s: %s", d, err)
	}

	t := time.NewTicker(HeartbeatSeconds * time.Second)
	go heartbeat(conn, t, msg, fromQueue, msgc, errc)

	// these functions will do their jobs when their channels have data
	go download(ctx, dl, processc, conn, d, errc, conn.GetLogger())
	go process(ctx, processc, upc, errc, conn.GetLogger())
	go up(ctx, upc, done, conn, bookname, errc, conn.GetLogger())

	dl <- msgparts[0]
	close(dl)

	// wait for either the done or errc channels to be sent to
	select {
	case err = <-errc:
		t.Stop()
		_ = os.RemoveAll(d)
		return err
	case <-ctx.Done():
		t.Stop()
		_ = os.RemoveAll(d)
		return ctx.Err()
	case <-done:
	}

	if allOCRed(bookname, conn) && toQueue != "" {
		conn.Log("Sending", bookname, "to queue", toQueue)
		err = conn.AddToQueue(toQueue, bookname)
		if err != nil {
			t.Stop()
			_ = os.RemoveAll(d)
			return fmt.Errorf("Error adding to queue %s: %s", bookname, err)
		}
	}

	t.Stop()

	// check whether we're using a newer msg handle
	select {
	case m, ok := <-msgc:
		if ok {
			msg = m
			conn.Log("Using new message handle to delete message from queue")
		}
	default:
		conn.Log("Using original message handle to delete message from queue")
	}

	conn.Log("Deleting original message from queue", fromQueue)
	err = conn.DelFromQueue(fromQueue, msg.Handle)
	if err != nil {
		_ = os.RemoveAll(d)
		return fmt.Errorf("Error deleting message from queue: %s", err)
	}

	err = os.RemoveAll(d)
	if err != nil {
		return fmt.Errorf("Failed to remove directory %s: %s", d, err)
	}

	return nil
}

func ProcessBook(ctx context.Context, msg bookpipeline.Qmsg, conn Pipeliner, process func(context.Context, chan string, chan string, chan error, *log.Logger), match *regexp.Regexp, fromQueue string, toQueue string) error {
	dl := make(chan string)
	msgc := make(chan bookpipeline.Qmsg)
	processc := make(chan string)
	upc := make(chan string)
	done := make(chan bool)
	errc := make(chan error)

	msgparts := strings.Split(msg.Body, " ")
	bookname := msgparts[0]

	var training string
	if len(msgparts) > 1 {
		training = msgparts[1]
	}

	d := filepath.Join(os.TempDir(), bookname)
	err := os.MkdirAll(d, 0755)
	if err != nil {
		return fmt.Errorf("Failed to create directory %s: %s", d, err)
	}

	t := time.NewTicker(HeartbeatSeconds * time.Second)
	go heartbeat(conn, t, msg, fromQueue, msgc, errc)

	// these functions will do their jobs when their channels have data
	go download(ctx, dl, processc, conn, d, errc, conn.GetLogger())
	go process(ctx, processc, upc, errc, conn.GetLogger())
	if toQueue == conn.OCRPageQueueId() {
		go upAndQueue(ctx, upc, done, toQueue, conn, bookname, training, errc, conn.GetLogger())
	} else {
		go up(ctx, upc, done, conn, bookname, errc, conn.GetLogger())
	}

	conn.Log("Getting list of objects to download")
	objs, err := conn.ListObjects(conn.WIPStorageId(), bookname)
	if err != nil {
		t.Stop()
		_ = os.RemoveAll(d)
		return fmt.Errorf("Failed to get list of files for book %s: %s", bookname, err)
	}
	var todl []string
	for _, n := range objs {
		if !match.MatchString(n) {
			conn.Log("Skipping item that doesn't match target", n)
			continue
		}
		todl = append(todl, n)
	}
	for _, a := range todl {
		dl <- a
	}
	close(dl)

	// wait for either the done or errc channel to be sent to
	select {
	case err = <-errc:
		t.Stop()
		_ = os.RemoveAll(d)
		// if the error is in preprocessing / wipeonly, chances are that it will never
		// complete, and will fill the ocrpage queue with parts which succeeded
		// on each run, so in that case it's better to delete the message from
		// the queue and notify us.
		if fromQueue == conn.PreQueueId() || fromQueue == conn.WipeQueueId() || fromQueue == conn.PreNoWipeQueueId() {
			conn.Log("Deleting message from queue due to a bad error", fromQueue)
			err2 := conn.DelFromQueue(fromQueue, msg.Handle)
			if err2 != nil {
				conn.Log("Error deleting message from queue", err2)
			}
			ms, err2 := GetMailSettings()
			if err2 != nil {
				conn.Log("Failed to mail settings ", err2)
			}
			if err2 == nil && ms.server != "" {
				logs, err2 := getLogs()
				if err2 != nil {
					conn.Log("Failed to get logs ", err2)
					logs = ""
				}
				msg := fmt.Sprintf("To: %s\r\nFrom: %s\r\n"+
					"Subject: [bookpipeline] Error in wipeonly / preprocessing queue with %s\r\n\r\n"+
					" Fail message: %s\r\nFull log:\r\n%s\r\n",
					ms.to, ms.from, bookname, err, logs)
				host := fmt.Sprintf("%s:%s", ms.server, ms.port)
				auth := smtp.PlainAuth("", ms.user, ms.pass, ms.server)
				err2 = smtp.SendMail(host, auth, ms.from, []string{ms.to}, []byte(msg))
				if err2 != nil {
					conn.Log("Error sending email ", err2)
				}
			}
		}
		return err
	case <-ctx.Done():
		t.Stop()
		_ = os.RemoveAll(d)
		return ctx.Err()
	case <-done:
	}

	if toQueue != "" && toQueue != conn.OCRPageQueueId() {
		conn.Log("Sending", bookname, "to queue", toQueue)
		err = conn.AddToQueue(toQueue, bookname)
		if err != nil {
			t.Stop()
			_ = os.RemoveAll(d)
			return fmt.Errorf("Error adding to queue %s: %s", bookname, err)
		}
	}

	t.Stop()

	// check whether we're using a newer msg handle
	select {
	case m, ok := <-msgc:
		if ok {
			msg = m
			conn.Log("Using new message handle to delete message from queue")
		}
	default:
		conn.Log("Using original message handle to delete message from queue")
	}

	conn.Log("Deleting original message from queue", fromQueue)
	err = conn.DelFromQueue(fromQueue, msg.Handle)
	if err != nil {
		_ = os.RemoveAll(d)
		return fmt.Errorf("Error deleting message from queue: %s", err)
	}

	err = os.RemoveAll(d)
	if err != nil {
		return fmt.Errorf("Failed to remove directory %s: %s", d, err)
	}

	return nil
}

// TODO: rather than relying on journald, would be nicer to save the logs
//       ourselves maybe, so that we weren't relying on a particular systemd
//       setup. this can be done by having the conn.Log also append line
//       to a file (though that would mean everything would have to go through
//       conn.Log, which we're not consistently doing yet). the correct thing
//       to do then would be to implement a new interface that covers the part
//       of log.Logger we use (e.g. Print and Printf), and then have an exported
//       conn struct that implements those, so that we could pass a log.Logger
//       or the new conn struct everywhere (we wouldn't be passing a log.Logger,
//       it's just good to be able to keep the compatibility)
func getLogs() (string, error) {
	cmd := exec.Command("journalctl", "-u", "bookpipeline", "-n", "all")
	var stdout, stderr bytes.Buffer
	cmd.Stdout = &stdout
	cmd.Stderr = &stderr
	err := cmd.Run()
	return stdout.String(), err
}

func SaveLogs(conn Uploader, starttime int64, hostname string) error {
	logs, err := getLogs()
	if err != nil {
		return fmt.Errorf("Error getting logs, error: %v", err)
	}
	key := fmt.Sprintf("bookpipeline.log.%d.%s", starttime, hostname)
	path := filepath.Join(os.TempDir(), key)
	f, err := os.Create(path)
	if err != nil {
		return fmt.Errorf("Error creating log file: %v", err)
	}
	defer f.Close()
	_, err = f.WriteString(logs)
	if err != nil {
		return fmt.Errorf("Error saving log file: %v", err)
	}
	_ = f.Close()
	err = conn.Upload(conn.WIPStorageId(), key, path)
	if err != nil {
		return fmt.Errorf("Error uploading log: %v", err)
	}
	conn.Log("Log saved to", key)
	return nil
}