summaryrefslogtreecommitdiff
path: root/Master/texmf-dist/tex/context/base/mkiv/lpdf-ini.lua
blob: 1b24269a68c3f8105ac9a645fb6882093f28bdcf (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
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
if not modules then modules = { } end modules ['lpdf-ini'] = {
    version   = 1.001,
    comment   = "companion to lpdf-ini.mkiv",
    author    = "Hans Hagen, PRAGMA-ADE, Hasselt NL",
    copyright = "PRAGMA ADE / ConTeXt Development Team",
    license   = "see context related readme files"
}

-- beware of "too many locals" here

local setmetatable, getmetatable, type, next, tostring, tonumber, rawset = setmetatable, getmetatable, type, next, tostring, tonumber, rawset
local char, byte, format, gsub, concat, match, sub, gmatch = string.char, string.byte, string.format, string.gsub, table.concat, string.match, string.sub, string.gmatch
local utfchar, utfbyte, utfvalues = utf.char, utf.byte, utf.values
local sind, cosd, floor, max, min = math.sind, math.cosd, math.floor, math.max, math.min
local sort = table.sort
local lpegmatch, P, C, R, S, Cc, Cs = lpeg.match, lpeg.P, lpeg.C, lpeg.R, lpeg.S, lpeg.Cc, lpeg.Cs
local formatters = string.formatters
local isboolean = string.is_boolean

local report_objects    = logs.reporter("backend","objects")
local report_finalizing = logs.reporter("backend","finalizing")
local report_blocked    = logs.reporter("backend","blocked")

local implement         = interfaces.implement
local two_strings       = interfaces.strings[2]

-- In ConTeXt MkIV we use utf8 exclusively so all strings get mapped onto a hex
-- encoded utf16 string type between <>. We could probably save some bytes by using
-- strings between () but then we end up with escaped ()\ too.

-- gethpos              : used
-- getpos               : used
-- getvpos              : used
--
-- getmatrix            : used
-- hasmatrix            : used
--
-- mapfile              : used in font-ctx.lua
-- mapline              : used in font-ctx.lua
--
-- maxobjnum            : not used
-- obj                  : used
-- immediateobj         : used
-- objtype              : not used
-- pageref              : used
-- print                : can be used
-- refobj               : used
-- registerannot        : not to be used
-- reserveobj           : used

-- pdf.catalog          : used
-- pdf.info             : used
-- pdf.trailer          : used
-- pdf.names            : not to be used

-- pdf.setinfo          : used
-- pdf.setcatalog       : used
-- pdf.setnames         : not to be used
-- pdf.settrailer       : used

-- pdf.getinfo          : used
-- pdf.getcatalog       : used
-- pdf.getnames         : not to be used
-- pdf.gettrailer       : used

local pdf    = pdf
local factor = number.dimenfactors.bp

do

    local texget = tex.get
    local texset = tex.set

    function pdf.setmajorversion (n) texset("global","pdfmajorversion", n) end
    function pdf.getmajorversion ( ) return texget("pdfmajorversion") end

end

local pdfsetinfo            = pdf.setinfo
local pdfsetcatalog         = pdf.setcatalog
----- pdfsetnames           = pdf.setnames
----- pdfsettrailer         = pdf.settrailer

local pdfsetpageresources   = pdf.setpageresources
local pdfsetpageattributes  = pdf.setpageattributes
local pdfsetpagesattributes = pdf.setpagesattributes

local pdfgetpos             = pdf.getpos
local pdfgethpos            = pdf.gethpos
local pdfgetvpos            = pdf.getvpos
local pdfgetmatrix          = pdf.getmatrix
local pdfhasmatrix          = pdf.hasmatrix

local pdfreserveobject      = pdf.reserveobj
local pdfimmediateobject    = pdf.immediateobj
local pdfdeferredobject     = pdf.obj
local pdfreferenceobject    = pdf.refobj

local function pdfdisablecommand(command)
    pdf[command] = function() report_blocked("'pdf.%s' is not supported",command) end
end

pdfdisablecommand("setinfo")
pdfdisablecommand("setcatalog")
pdfdisablecommand("setnames")
pdfdisablecommand("settrailer")
pdfdisablecommand("setpageresources")
pdfdisablecommand("setpageattributes")
pdfdisablecommand("setpagesattributes")
pdfdisablecommand("registerannot")

local trace_finalizers = false  trackers.register("backend.finalizers", function(v) trace_finalizers = v end)
local trace_resources  = false  trackers.register("backend.resources",  function(v) trace_resources  = v end)
local trace_objects    = false  trackers.register("backend.objects",    function(v) trace_objects    = v end)
local trace_detail     = false  trackers.register("backend.detail",     function(v) trace_detail     = v end)

local backends   = backends
local pdfbackend = {
    comment        = "backend for directly generating pdf output",
    nodeinjections = { },
    codeinjections = { },
    registrations  = { },
    tables         = { },
}
backends.pdf     = pdfbackend
lpdf             = lpdf or { }
local lpdf       = lpdf

local codeinjections = pdfbackend.codeinjections
local nodeinjections = pdfbackend.nodeinjections

codeinjections.getpos    = pdfgetpos     lpdf.getpos    = pdfgetpos
codeinjections.gethpos   = pdfgethpos    lpdf.gethpos   = pdfgethpos
codeinjections.getvpos   = pdfgetvpos    lpdf.getvpos   = pdfgetvpos
codeinjections.hasmatrix = pdfhasmatrix  lpdf.hasmatrix = pdfhasmatrix
codeinjections.getmatrix = pdfgetmatrix  lpdf.getmatrix = pdfgetmatrix

-- local function transform(llx,lly,urx,ury,rx,sx,sy,ry)
--     local x1 = llx * rx + lly * sy
--     local y1 = llx * sx + lly * ry
--     local x2 = llx * rx + ury * sy
--     local y2 = llx * sx + ury * ry
--     local x3 = urx * rx + lly * sy
--     local y3 = urx * sx + lly * ry
--     local x4 = urx * rx + ury * sy
--     local y4 = urx * sx + ury * ry
--     llx = min(x1,x2,x3,x4);
--     lly = min(y1,y2,y3,y4);
--     urx = max(x1,x2,x3,x4);
--     ury = max(y1,y2,y3,y4);
--     return llx, lly, urx, ury
-- end

function lpdf.transform(llx,lly,urx,ury) -- not yet used so unchecked
    if pdfhasmatrix() then
        local sx, rx, ry, sy = pdfgetmatrix()
        local w, h = urx - llx, ury - lly
        return llx, lly, llx + sy*w - ry*h, lly + sx*h - rx*w
     -- return transform(llx,lly,urx,ury,sx,rx,ry,sy)
    else
        return llx, lly, urx, ury
    end
end

-- funny values for tx and ty

function lpdf.rectangle(width,height,depth,offset)
    local tx, ty = pdfgetpos()
    if offset then
        tx     = tx     -   offset
        ty     = ty     +   offset
        width  = width  + 2*offset
        height = height +   offset
        depth  = depth  +   offset
    end
    if pdfhasmatrix() then
        local rx, sx, sy, ry = pdfgetmatrix()
        return
            factor *  tx,
            factor * (ty - ry*depth  + sx*width),
            factor * (tx + rx*width  - sy*height),
            factor * (ty + ry*height - sx*width)
    else
        return
            factor *  tx,
            factor * (ty - depth),
            factor * (tx + width),
            factor * (ty + height)
    end
end

-- we could use a hash of predefined unicodes

-- local function tosixteen(str) -- an lpeg might be faster (no table)
--     if not str or str == "" then
--         return "<feff>" -- not () as we want an indication that it's unicode
--     else
--         local r, n = { "<feff" }, 1
--         for b in utfvalues(str) do
--             n = n + 1
--             if b < 0x10000 then
--                 r[n] = format("%04x",b)
--             else
--              -- r[n] = format("%04x%04x",b/1024+0xD800,b%1024+0xDC00)
--                 r[n] = format("%04x%04x",floor(b/1024),b%1024+0xDC00) --bit32.rshift(b,10)
--             end
--         end
--         n = n + 1
--         r[n] = ">"
--         return concat(r)
--     end
-- end

local cache = table.setmetatableindex(function(t,k) -- can be made weak
    local v = utfbyte(k)
    if v < 0x10000 then
        v = format("%04x",v)
    else
     -- v = format("%04x%04x",v/1024+0xD800,v%1024+0xDC00)
        v = format("%04x%04x",floor(v/1024),v%1024+0xDC00)
    end
    t[k] = v
    return v
end)

local escaped = Cs(Cc("(") * (S("\\()")/"\\%0" + P(1))^0 * Cc(")"))
local unified = Cs(Cc("<feff") * (lpeg.patterns.utf8character/cache)^1 * Cc(">"))

local function tosixteen(str) -- an lpeg might be faster (no table)
    if not str or str == "" then
        return "<feff>" -- not () as we want an indication that it's unicode
    else
        return lpegmatch(unified,str)
    end
end

local more = 0

local pattern = C(4) / function(s) -- needs checking !
    local now = tonumber(s,16)
    if more > 0 then
        now = (more-0xD800)*0x400 + (now-0xDC00) + 0x10000 -- the 0x10000 smells wrong
        more = 0
        return utfchar(now)
    elseif now >= 0xD800 and now <= 0xDBFF then
        more = now
        return "" -- else the c's end up in the stream
    else
        return utfchar(now)
    end
end

local pattern = P(true) / function() more = 0 end * Cs(pattern^0)

local function fromsixteen(str)
    if not str or str == "" then
        return ""
    else
        return lpegmatch(pattern,str)
    end
end

local toregime   = regimes.toregime
local fromregime = regimes.fromregime

local function topdfdoc(str,default)
    if not str or str == "" then
        return ""
    else
        return lpegmatch(escaped,toregime("pdfdoc",str,default)) -- could be combined if needed
    end
end

local function frompdfdoc(str)
    if not str or str == "" then
        return ""
    else
        return fromregime("pdfdoc",str)
    end
end

if not toregime   then topdfdoc   = function(s) return s end end
if not fromregime then frompdfdoc = function(s) return s end end

local function toeight(str)
    if not str or str == "" then
        return "()"
    else
        return lpegmatch(escaped,str)
    end
end

lpdf.tosixteen   = tosixteen
lpdf.toeight     = toeight
lpdf.topdfdoc    = topdfdoc
lpdf.fromsixteen = fromsixteen
lpdf.frompdfdoc  = frompdfdoc

local function merge_t(a,b)
    local t = { }
    for k,v in next, a do t[k] = v end
    for k,v in next, b do t[k] = v end
    return setmetatable(t,getmetatable(a))
end

local f_key_null       = formatters["/%s null"]
local f_key_value      = formatters["/%s %s"]
local f_key_dictionary = formatters["/%s << % t >>"]
local f_dictionary     = formatters["<< % t >>"]
local f_key_array      = formatters["/%s [ % t ]"]
local f_array          = formatters["[ % t ]"]
local f_key_number     = formatters["/%s %F"]
local f_tonumber       = formatters["%F"]

local tostring_a, tostring_d

tostring_d = function(t,contentonly,key)
    if next(t) then
        local r, n = { }, 0
        for k in next, t do
            n = n + 1
            r[n] = k
        end
        sort(r)
        for i=1,n do
            local k  = r[i]
            local v  = t[k]
            local tv = type(v)
            if tv == "string" then
                r[i] = f_key_value(k,toeight(v))
            elseif tv == "number" then
                r[i] = f_key_number(k,v)
         -- elseif tv == "unicode" then -- can't happen
         --     r[i] = f_key_value(k,tosixteen(v))
            elseif tv == "table" then
                local mv = getmetatable(v)
                if mv and mv.__lpdftype then
                 -- if v == t then
                 --     report_objects("ignoring circular reference in dirctionary")
                 --     r[i] = f_key_null(k)
                 -- else
                        r[i] = f_key_value(k,tostring(v))
                 -- end
                elseif v[1] then
                    r[i] = f_key_value(k,tostring_a(v))
                else
                    r[i] = f_key_value(k,tostring_d(v))
                end
            else
                r[i] = f_key_value(k,tostring(v))
            end
        end
        if contentonly then
            return concat(r," ")
        elseif key then
            return f_key_dictionary(key,r)
        else
            return f_dictionary(r)
        end
    elseif contentonly then
        return ""
    else
        return "<< >>"
    end
end

tostring_a = function(t,contentonly,key)
    local tn = #t
    if tn ~= 0 then
        local r = { }
        for k=1,tn do
            local v = t[k]
            local tv = type(v)
            if tv == "string" then
                r[k] = toeight(v)
            elseif tv == "number" then
                r[k] = f_tonumber(v)
         -- elseif tv == "unicode" then
         --     r[k] = tosixteen(v)
            elseif tv == "table" then
                local mv = getmetatable(v)
                local mt = mv and mv.__lpdftype
                if mt then
                 -- if v == t then
                 --     report_objects("ignoring circular reference in array")
                 --     r[k] = "null"
                 -- else
                        r[k] = tostring(v)
                 -- end
                elseif v[1] then
                    r[k] = tostring_a(v)
                else
                    r[k] = tostring_d(v)
                end
            else
                r[k] = tostring(v)
            end
        end
        if contentonly then
            return concat(r, " ")
        elseif key then
            return f_key_array(key,r)
        else
            return f_array(r)
        end
    elseif contentonly then
        return ""
    else
        return "[ ]"
    end
end

local tostring_x = function(t) return concat(t," ")       end
local tostring_s = function(t) return toeight(t[1])       end
local tostring_p = function(t) return topdfdoc(t[1],t[2]) end
local tostring_u = function(t) return tosixteen(t[1])     end
----- tostring_n = function(t) return tostring(t[1])      end -- tostring not needed
local tostring_n = function(t) return f_tonumber(t[1])    end -- tostring not needed
local tostring_c = function(t) return t[1]                end -- already prefixed (hashed)
local tostring_z = function()  return "null"              end
local tostring_t = function()  return "true"              end
local tostring_f = function()  return "false"             end
local tostring_r = function(t) local n = t[1] return n and n > 0 and (n .. " 0 R") or "null" end

local tostring_v = function(t)
    local s = t[1]
    if type(s) == "table" then
        return concat(s)
    else
        return s
    end
end

local function value_x(t) return t                  end
local function value_s(t) return t[1]               end
local function value_p(t) return t[1]               end
local function value_u(t) return t[1]               end
local function value_n(t) return t[1]               end
local function value_c(t) return sub(t[1],2)        end
local function value_d(t) return tostring_d(t,true) end
local function value_a(t) return tostring_a(t,true) end
local function value_z()  return nil                end
local function value_t(t) return t.value or true    end
local function value_f(t) return t.value or false   end
local function value_r()  return t[1] or 0          end -- null
local function value_v()  return t[1]               end

local function add_x(t,k,v) rawset(t,k,tostring(v)) end

local mt_x = { __lpdftype = "stream",     __tostring = tostring_x, __call = value_x, __newindex = add_x }
local mt_d = { __lpdftype = "dictionary", __tostring = tostring_d, __call = value_d }
local mt_a = { __lpdftype = "array",      __tostring = tostring_a, __call = value_a }
local mt_u = { __lpdftype = "unicode",    __tostring = tostring_u, __call = value_u }
local mt_s = { __lpdftype = "string",     __tostring = tostring_s, __call = value_s }
local mt_p = { __lpdftype = "docstring",  __tostring = tostring_p, __call = value_p }
local mt_n = { __lpdftype = "number",     __tostring = tostring_n, __call = value_n }
local mt_c = { __lpdftype = "constant",   __tostring = tostring_c, __call = value_c }
local mt_z = { __lpdftype = "null",       __tostring = tostring_z, __call = value_z }
local mt_t = { __lpdftype = "true",       __tostring = tostring_t, __call = value_t }
local mt_f = { __lpdftype = "false",      __tostring = tostring_f, __call = value_f }
local mt_r = { __lpdftype = "reference",  __tostring = tostring_r, __call = value_r }
local mt_v = { __lpdftype = "verbose",    __tostring = tostring_v, __call = value_v }

local function pdfstream(t) -- we need to add attributes
    if t then
        local tt = type(t)
        if tt == "table" then
            for i=1,#t do
                t[i] = tostring(t[i])
            end
        elseif tt == "string" then
            t= { t }
        else
            t= { tostring(t) }
        end
    end
    return setmetatable(t or { },mt_x)
end

local function pdfdictionary(t)
    return setmetatable(t or { },mt_d)
end

local function pdfarray(t)
    if type(t) == "string" then
        return setmetatable({ t },mt_a)
    else
        return setmetatable(t or { },mt_a)
    end
end

local function pdfstring(str,default)
    return setmetatable({ str or default or "" },mt_s)
end

local function pdfdocstring(str,default,defaultchar)
    return setmetatable({ str or default or "", defaultchar or " " },mt_p)
end

local function pdfunicode(str,default)
    return setmetatable({ str or default or "" },mt_u) -- could be a string
end

local cache = { } -- can be weak

local function pdfnumber(n,default) -- 0-10
    n = n or default
    local c = cache[n]
    if not c then
        c = setmetatable({ n },mt_n)
    --  cache[n] = c -- too many numbers
    end
    return c
end

for i=-1,9 do cache[i] = pdfnumber(i) end

local cache = { } -- can be weak

local forbidden, replacements = "\0\t\n\r\f ()[]{}/%%#\\", { } -- table faster than function

for s in gmatch(forbidden,".") do
    replacements[s] = format("#%02x",byte(s))
end

local escaped = Cs(Cc("/") * (S(forbidden)/replacements + P(1))^0)

local function pdfconstant(str,default)
    str = str or default or ""
    local c = cache[str]
    if not c then
     -- c = setmetatable({ "/" .. str },mt_c)
        c = setmetatable({ lpegmatch(escaped,str) },mt_c)
        cache[str] = c
    end
    return c
end

local escaped = Cs((S(forbidden)/replacements + P(1))^0)
----- escaped = Cs((1-forbidden)^0 * S(forbidden)/replacements * ((S(forbidden)/replacements + P(1))^0)

function lpdf.escaped(str)
    return lpegmatch(escaped,str) or str
end

do

    local p_null  = { } setmetatable(p_null, mt_z)
    local p_true  = { } setmetatable(p_true, mt_t)
    local p_false = { } setmetatable(p_false,mt_f)

    pdfnull = function()
        return p_null
    end

    pdfboolean = function(b,default)
        if type(b) == "boolean" then
            return b and p_true or p_false
        else
            return default and p_true or p_false
        end
    end

    -- print(pdfboolean(false),pdfboolean(false,false),pdfboolean(false,true))
    -- print(pdfboolean(true),pdfboolean(true,false),pdfboolean(true,true))
    -- print(pdfboolean(nil,true),pdfboolean(nil,false))

    local r_zero = setmetatable({ 0 },mt_r)

    pdfreference = function(r)  -- maybe make a weak table
        if r and r ~= 0 then
            return setmetatable({ r },mt_r)
        else
            return r_zero
        end
    end

    local v_zero  = setmetatable({ 0  },mt_v)
    local v_empty = setmetatable({ "" },mt_v)

    pdfverbose = function(t) -- maybe check for type
        if t == 0 then
            return v_zero
        elseif t == "" then
            return v_empty
        else
            return setmetatable({ t },mt_v)
        end
    end

end

lpdf.stream      = pdfstream -- THIS WILL PROBABLY CHANGE
lpdf.dictionary  = pdfdictionary
lpdf.array       = pdfarray
lpdf.docstring   = pdfdocstring
lpdf.string      = pdfstring
lpdf.unicode     = pdfunicode
lpdf.number      = pdfnumber
lpdf.constant    = pdfconstant
lpdf.null        = pdfnull
lpdf.boolean     = pdfboolean
lpdf.reference   = pdfreference
lpdf.verbose     = pdfverbose

local names, cache = { }, { }

function lpdf.reserveobject(name)
    local r = pdfreserveobject() -- we don't support "annot"
    if name then
        names[name] = r
        if trace_objects then
            report_objects("reserving number %a under name %a",r,name)
        end
    elseif trace_objects then
        report_objects("reserving number %a",r)
    end
    return r
end

-- lpdf.immediateobject = pdfimmediateobject
-- lpdf.deferredobject  = pdfdeferredobject
-- lpdf.object          = pdfdeferredobject
-- lpdf.referenceobject = pdfreferenceobject

local pagereference = pdf.pageref -- tex.pdfpageref is obsolete
local nofpages      = 0

function lpdf.pagereference(n)
    if nofpages == 0 then
        nofpages = structures.pages.nofpages
        if nofpages == 0 then
            nofpages = 1
        end
    end
    if n > nofpages then
        return pagereference(nofpages) -- or 1, could be configureable
    else
        return pagereference(n)
    end
end

function lpdf.delayedobject(data,n)
    if n then
        pdfdeferredobject(n,data)
    else
        n = pdfdeferredobject(data)
    end
    pdfreferenceobject(n)
    return n
end

function lpdf.flushobject(name,data)
    if data then
        local named = names[name]
        if named then
            if not trace_objects then
            elseif trace_detail then
                report_objects("flushing data to reserved object with name %a, data: %S",name,data)
            else
                report_objects("flushing data to reserved object with name %a",name)
            end
            return pdfimmediateobject(named,tostring(data))
        else
            if not trace_objects then
            elseif trace_detail then
                report_objects("flushing data to reserved object with number %s, data: %S",name,data)
            else
                report_objects("flushing data to reserved object with number %s",name)
            end
            return pdfimmediateobject(name,tostring(data))
        end
    else
        if trace_objects and trace_detail then
            report_objects("flushing data: %S",name)
        end
        return pdfimmediateobject(tostring(name))
    end
end


function lpdf.flushstreamobject(data,dict,compressed) -- default compressed
    if trace_objects then
        report_objects("flushing stream object of %s bytes",#data)
    end
    local dtype = type(dict)
    return pdfdeferredobject {
        immediate     = true,
        compresslevel = compressed == false and 0 or nil,
        type          = "stream",
        string        = data,
        attr          = (dtype == "string" and dict) or (dtype == "table" and dict()) or nil,
    }
end

function lpdf.flushstreamfileobject(filename,dict,compressed) -- default compressed
    if trace_objects then
        report_objects("flushing stream file object %a",filename)
    end
    local dtype = type(dict)
    return pdfdeferredobject {
        immediate     = true,
        compresslevel = compressed == false and 0 or nil,
        type          = "stream",
        file          = filename,
        attr          = (dtype == "string" and dict) or (dtype == "table" and dict()) or nil,
    }
end

local shareobjectcache, shareobjectreferencecache = { }, { }

function lpdf.shareobject(content)
    if content == nil then
        -- invalid object not created
    else
        content = tostring(content)
        local o = shareobjectcache[content]
        if not o then
            o = pdfimmediateobject(content)
            shareobjectcache[content] = o
        end
        return o
    end
end

function lpdf.shareobjectreference(content)
    if content == nil then
        -- invalid object not created
    else
        content = tostring(content)
        local r = shareobjectreferencecache[content]
        if not r then
            local o = shareobjectcache[content]
            if not o then
                o = pdfimmediateobject(content)
                shareobjectcache[content] = o
            end
            r = pdfreference(o)
            shareobjectreferencecache[content] = r
        end
        return r
    end
end

-- three priority levels, default=2

local pagefinalizers     = { { }, { }, { } }
local documentfinalizers = { { }, { }, { } }

local pageresources, pageattributes, pagesattributes

local function resetpageproperties()
    pageresources   = pdfdictionary()
    pageattributes  = pdfdictionary()
    pagesattributes = pdfdictionary()
end

resetpageproperties()

local function setpageproperties()
    pdfsetpageresources  (pageresources  ())
    pdfsetpageattributes (pageattributes ())
    pdfsetpagesattributes(pagesattributes())
end

local function addtopageresources  (k,v) pageresources  [k] = v end
local function addtopageattributes (k,v) pageattributes [k] = v end
local function addtopagesattributes(k,v) pagesattributes[k] = v end

lpdf.addtopageresources   = addtopageresources
lpdf.addtopageattributes  = addtopageattributes
lpdf.addtopagesattributes = addtopagesattributes

local function set(where,what,f,when,comment)
    if type(when) == "string" then
        when, comment = 2, when
    elseif not when then
        when = 2
    end
    local w = where[when]
    w[#w+1] = { f, comment }
    if trace_finalizers then
        report_finalizing("%s set: [%s,%s]",what,when,#w)
    end
end

local function run(where,what)
    if trace_finalizers then
        report_finalizing("start backend, category %a, n %a",what,#where)
    end
    for i=1,#where do
        local w = where[i]
        for j=1,#w do
            local wj = w[j]
            if trace_finalizers then
                report_finalizing("%s finalizer: [%s,%s] %s",what,i,j,wj[2] or "")
            end
            wj[1]()
        end
    end
    if trace_finalizers then
        report_finalizing("stop finalizing")
    end
end

local function registerpagefinalizer(f,when,comment)
    set(pagefinalizers,"page",f,when,comment)
end

local function registerdocumentfinalizer(f,when,comment)
    set(documentfinalizers,"document",f,when,comment)
end

lpdf.registerpagefinalizer     = registerpagefinalizer
lpdf.registerdocumentfinalizer = registerdocumentfinalizer

function lpdf.finalizepage(shipout)
    if shipout and not environment.initex then
     -- resetpageproperties() -- maybe better before
        run(pagefinalizers,"page")
        setpageproperties()
        resetpageproperties() -- maybe better before
    end
end

function lpdf.finalizedocument()
    if not environment.initex then
        run(documentfinalizers,"document")
        function lpdf.finalizedocument()
            report_finalizing("serious error: the document is finalized multiple times")
            function lpdf.finalizedocument() end
        end
    end
end

-- codeinjections.finalizepage = lpdf.finalizepage -- no longer triggered at the tex end

if not callbacks.register("finish_pdfpage", lpdf.finalizepage) then

    local find_tail    = nodes.tail
    local latelua_node = nodes.pool.latelua

    function nodeinjections.finalizepage(head)
        local t = find_tail(head.list)
        if t then
            local n = latelua_node("lpdf.finalizepage(true)") -- last in the shipout
            t.next = n
            n.prev = t
        end
        return head, true
    end

    nodes.tasks.appendaction("shipouts","normalizers","backends.pdf.nodeinjections.finalizepage")

end

callbacks.register("finish_pdffile", lpdf.finalizedocument)


do

    -- some minimal tracing, handy for checking the order

    local function trace_set(what,key)
        if trace_resources then
            report_finalizing("setting key %a in %a",key,what)
        end
    end

    local function trace_flush(what)
        if trace_resources then
            report_finalizing("flushing %a",what)
        end
    end

    lpdf.protectresources = true

    local catalog = pdfdictionary { Type = pdfconstant("Catalog") } -- nicer, but when we assign we nil the Type
    local info    = pdfdictionary { Type = pdfconstant("Info")    } -- nicer, but when we assign we nil the Type
    ----- names   = pdfdictionary { Type = pdfconstant("Names")   } -- nicer, but when we assign we nil the Type

    local function flushcatalog()
        if not environment.initex then
            trace_flush("catalog")
            catalog.Type = nil
            pdfsetcatalog(catalog())
        end
    end

    local function flushinfo()
        if not environment.initex then
            trace_flush("info")
            info.Type = nil
            pdfsetinfo(info())
        end
    end

    -- local function flushnames()
    --     if not environment.initex then
    --         trace_flush("names")
    --         names.Type = nil
    --         pdfsetnames(names())
    --     end
    -- end

    function lpdf.addtocatalog(k,v)
        if not (lpdf.protectresources and catalog[k]) then
            trace_set("catalog",k)
            catalog[k] = v
        end
    end

    function lpdf.addtoinfo(k,v)
        if not (lpdf.protectresources and info[k]) then
            trace_set("info",k)
            info[k] = v
        end
    end

    -- local function lpdf.addtonames(k,v)
    --     if not (lpdf.protectresources and names[k]) then
    --         trace_set("names",k)
    --         names[k] = v
    --     end
    -- end

    local names = pdfdictionary {
     -- Type = pdfconstant("Names")
    }

    local function flushnames()
        if next(names) and not environment.initex then
            names.Type = pdfconstant("Names")
            trace_flush("names")
            lpdf.addtocatalog("Names",pdfreference(pdfimmediateobject(tostring(names))))
        end
    end

    function lpdf.addtonames(k,v)
        if not (lpdf.protectresources and names[k]) then
            trace_set("names",  k)
            names  [k] = v
        end
    end

    local r_extgstates,  d_extgstates  = pdfreserveobject(), pdfdictionary()  local p_extgstates  = pdfreference(r_extgstates)
    local r_colorspaces, d_colorspaces = pdfreserveobject(), pdfdictionary()  local p_colorspaces = pdfreference(r_colorspaces)
    local r_patterns,    d_patterns    = pdfreserveobject(), pdfdictionary()  local p_patterns    = pdfreference(r_patterns)
    local r_shades,      d_shades      = pdfreserveobject(), pdfdictionary()  local p_shades      = pdfreference(r_shades)

    local function checkextgstates () if next(d_extgstates ) then addtopageresources("ExtGState", p_extgstates ) end end
    local function checkcolorspaces() if next(d_colorspaces) then addtopageresources("ColorSpace",p_colorspaces) end end
    local function checkpatterns   () if next(d_patterns   ) then addtopageresources("Pattern",   p_patterns   ) end end
    local function checkshades     () if next(d_shades     ) then addtopageresources("Shading",   p_shades     ) end end

    local function flushextgstates () if next(d_extgstates ) then trace_flush("extgstates")  pdfimmediateobject(r_extgstates, tostring(d_extgstates )) end end
    local function flushcolorspaces() if next(d_colorspaces) then trace_flush("colorspaces") pdfimmediateobject(r_colorspaces,tostring(d_colorspaces)) end end
    local function flushpatterns   () if next(d_patterns   ) then trace_flush("patterns")    pdfimmediateobject(r_patterns,   tostring(d_patterns   )) end end
    local function flushshades     () if next(d_shades     ) then trace_flush("shades")      pdfimmediateobject(r_shades,     tostring(d_shades     )) end end

    -- patterns are special as they need resources to so we can get recursive references and in that case
    -- acrobat doesn't show anything (other viewers handle it well)
    --
    -- todo: share them
    -- todo: force when not yet set

    function lpdf.collectedresources(options)
        local ExtGState  = next(d_extgstates ) and p_extgstates
        local ColorSpace = next(d_colorspaces) and p_colorspaces
        local Pattern    = next(d_patterns   ) and p_patterns
        local Shading    = next(d_shades     ) and p_shades
        if options and options.patterns == false then
            Pattern = nil
        end
        if ExtGState or ColorSpace or Pattern or Shading then
            local collected = pdfdictionary {
                ExtGState  = ExtGState,
                ColorSpace = ColorSpace,
                Pattern    = Pattern,
                Shading    = Shading,
             -- ProcSet    = pdfarray { pdfconstant("PDF") },
            }
            return collected()
        else
            return ""
        end
    end

    function lpdf.adddocumentextgstate (k,v) d_extgstates [k] = v end
    function lpdf.adddocumentcolorspace(k,v) d_colorspaces[k] = v end
    function lpdf.adddocumentpattern   (k,v) d_patterns   [k] = v end
    function lpdf.adddocumentshade     (k,v) d_shades     [k] = v end

    registerdocumentfinalizer(flushextgstates,3,"extended graphic states")
    registerdocumentfinalizer(flushcolorspaces,3,"color spaces")
    registerdocumentfinalizer(flushpatterns,3,"patterns")
    registerdocumentfinalizer(flushshades,3,"shades")

    registerdocumentfinalizer(flushnames,3,"names") -- before catalog
    registerdocumentfinalizer(flushcatalog,3,"catalog")
    registerdocumentfinalizer(flushinfo,3,"info")

    registerpagefinalizer(checkextgstates,3,"extended graphic states")
    registerpagefinalizer(checkcolorspaces,3,"color spaces")
    registerpagefinalizer(checkpatterns,3,"patterns")
    registerpagefinalizer(checkshades,3,"shades")

end

-- in strc-bkm: lpdf.registerdocumentfinalizer(function() structures.bookmarks.place() end,1)

function lpdf.rotationcm(a)
    local s, c = sind(a), cosd(a)
    return format("%0.6F %0.6F %0.6F %0.6F 0 0 cm",c,s,-s,c)
end

-- ! -> universaltime

do

    local timestamp = backends.timestamp()

    function lpdf.timestamp()
        return timestamp
    end

    function lpdf.settime(n)
        if n then
            n = converters.totime(n)
            if n then
                converters.settime(n)
                timestamp = backends.timestamp()
            end
        end
        return timestamp
    end

    lpdf.settime(tonumber(resolvers.variable("start_time")) or tonumber(resolvers.variable("SOURCE_DATE_EPOCH"))) -- bah

    function lpdf.pdftimestamp(str)
        local Y, M, D, h, m, s, Zs, Zh, Zm = match(str,"^(%d%d%d%d)%-(%d%d)%-(%d%d)T(%d%d):(%d%d):(%d%d)([%+%-])(%d%d):(%d%d)$")
        return Y and format("D:%s%s%s%s%s%s%s%s'%s'",Y,M,D,h,m,s,Zs,Zh,Zm)
    end

    function lpdf.id(nodate)
        if nodate then
            return tex.jobname
        else
            return format("%s.%s",tex.jobname,timestamp)
        end
    end

end

-- return nil is nicer in test prints

function lpdf.checkedkey(t,key,variant)
    local pn = t and t[key]
    if pn ~= nil then
        local tn = type(pn)
        if tn == variant then
            if variant == "string" then
                if pn ~= "" then
                    return pn
                end
            elseif variant == "table" then
                if next(pn) then
                    return pn
                end
            else
                return pn
            end
        elseif tn == "string" then
            if variant == "number" then
                return tonumber(pn)
            elseif variant == "boolean" then
                return isboolean(pn,nil,true)
            end
        end
    end
 -- return nil
end

function lpdf.checkedvalue(value,variant) -- code not shared
    if value ~= nil then
        local tv = type(value)
        if tv == variant then
            if variant == "string" then
                if value ~= "" then
                    return value
                end
            elseif variant == "table" then
                if next(value) then
                    return value
                end
            else
                return value
            end
        elseif tv == "string" then
            if variant == "number" then
                return tonumber(value)
            elseif variant == "boolean" then
                return isboolean(value,nil,true)
            end
        end
    end
 -- return nil
end

function lpdf.limited(n,min,max,default)
    if not n then
        return default
    else
        n = tonumber(n)
        if not n then
            return default
        elseif n > max then
            return max
        elseif n < min then
            return min
        else
            return n
        end
    end
end

-- if not pdfreferenceobject then
--
--     local delayed = { }
--
--     local function flush()
--         local n = 0
--         for k,v in next, delayed do
--             pdfimmediateobject(k,v)
--             n = n + 1
--         end
--         if trace_objects then
--             report_objects("%s objects flushed",n)
--         end
--         delayed = { }
--     end
--
--     lpdf.registerdocumentfinalizer(flush,3,"objects") -- so we need a final flush too
--     lpdf.registerpagefinalizer    (flush,3,"objects") -- somehow this lags behind .. I need to look into that some day
--
--     function lpdf.delayedobject(data)
--         local n = pdfreserveobject()
--         delayed[n] = data
--         return n
--     end
--
-- end

-- setmetatable(pdf, {
--     __index = function(t,k)
--         if     k == "info"           then return pdf.getinfo()
--         elseif k == "catalog"        then return pdf.getcatalog()
--         elseif k == "names"          then return pdf.getnames()
--         elseif k == "trailer"        then return pdf.gettrailer()
--         elseif k == "pageattribute"  then return pdf.getpageattribute()
--         elseif k == "pageattributes" then return pdf.getpageattributes()
--         elseif k == "pageresources"  then return pdf.getpageresources()
--         elseif
--             return nil
--         end
--     end,
--     __newindex = function(t,k,v)
--         if     k == "info"           then return pdf.setinfo(v)
--         elseif k == "catalog"        then return pdf.setcatalog(v)
--         elseif k == "names"          then return pdf.setnames(v)
--         elseif k == "trailer"        then return pdf.settrailer(v)
--         elseif k == "pageattribute"  then return pdf.setpageattribute(v)
--         elseif k == "pageattributes" then return pdf.setpageattributes(v)
--         elseif k == "pageresources"  then return pdf.setpageresources(v)
--         else
--             rawset(t,k,v)
--         end
--     end,
-- })


-- The next variant of ActualText is what Taco and I could come up with
-- eventually. As of September 2013 Acrobat copies okay, Sumatra copies a
-- question mark, pdftotext injects an extra space and Okular adds a
-- newline plus space.

-- return formatters["BT /Span << /ActualText (CONTEXT) >> BDC [<feff>] TJ % t EMC ET"](code)

do

    local f_actual_text_one       = formatters["BT /Span << /ActualText <feff%04x> >> BDC %s EMC ET"]
    local f_actual_text_two       = formatters["BT /Span << /ActualText <feff%04x%04x> >> BDC %s EMC ET"]
    local f_actual_text_one_b     = formatters["BT /Span << /ActualText <feff%04x> >> BDC"]
    local f_actual_text_two_b     = formatters["BT /Span << /ActualText <feff%04x%04x> >> BDC"]
    local f_actual_text_b         = formatters["BT /Span << /ActualText <feff%s> >> BDC"]
    local s_actual_text_e         = "EMC ET"
    local f_actual_text_b_not     = formatters["/Span << /ActualText <feff%s> >> BDC"]
    local f_actual_text_one_b_not = formatters["/Span << /ActualText <feff%04x> >> BDC"]
    local f_actual_text_two_b_not = formatters["/Span << /ActualText <feff%04x%04x> >> BDC"]
    local s_actual_text_e_not     = "EMC"
    local f_actual_text           = formatters["/Span <</ActualText %s >> BDC"]

    local context   = context
    local pdfdirect = nodes.pool.pdfdirect

    -- todo: use tounicode from the font mapper

    function codeinjections.unicodetoactualtext(unicode,pdfcode)
        if unicode < 0x10000 then
            return f_actual_text_one(unicode,pdfcode)
        else
            return f_actual_text_two(unicode/1024+0xD800,unicode%1024+0xDC00,pdfcode)
        end
    end

    function codeinjections.startunicodetoactualtext(unicode)
        if type(unicode) == "string" then
            return f_actual_text_b(unicode)
        elseif unicode < 0x10000 then
            return f_actual_text_one_b(unicode)
        else
            return f_actual_text_two_b(unicode/1024+0xD800,unicode%1024+0xDC00)
        end
    end

    function codeinjections.stopunicodetoactualtext()
        return s_actual_text_e
    end

    function codeinjections.startunicodetoactualtextdirect(unicode)
        if type(unicode) == "string" then
            return f_actual_text_b_not(unicode)
        elseif unicode < 0x10000 then
            return f_actual_text_one_b_not(unicode)
        else
            return f_actual_text_two_b_not(unicode/1024+0xD800,unicode%1024+0xDC00)
        end
    end

    function codeinjections.stopunicodetoactualtextdirect()
        return s_actual_text_e_not
    end

    implement {
        name      = "startactualtext",
        arguments = "string",
        actions   = function(str)
            context(pdfdirect(f_actual_text(tosixteen(str))))
        end
    }

    implement {
        name      = "stopactualtext",
        actions   = function()
            context(pdfdirect("EMC"))
        end
    }

end

-- interface

implement { name = "lpdf_collectedresources",                             actions = { lpdf.collectedresources, context } }
implement { name = "lpdf_addtocatalog",          arguments = two_strings, actions = lpdf.addtocatalog }
implement { name = "lpdf_addtoinfo",             arguments = two_strings, actions = function(a,b,c) lpdf.addtoinfo(a,b,c) end } -- gets adapted
implement { name = "lpdf_addtonames",            arguments = two_strings, actions = lpdf.addtonames }
implement { name = "lpdf_addtopageattributes",   arguments = two_strings, actions = lpdf.addtopageattributes }
implement { name = "lpdf_addtopagesattributes",  arguments = two_strings, actions = lpdf.addtopagesattributes }
implement { name = "lpdf_addtopageresources",    arguments = two_strings, actions = lpdf.addtopageresources }
implement { name = "lpdf_adddocumentextgstate",  arguments = two_strings, actions = function(a,b) lpdf.adddocumentextgstate (a,pdfverbose(b)) end }
implement { name = "lpdf_adddocumentcolorspace", arguments = two_strings, actions = function(a,b) lpdf.adddocumentcolorspace(a,pdfverbose(b)) end }
implement { name = "lpdf_adddocumentpattern",    arguments = two_strings, actions = function(a,b) lpdf.adddocumentpattern   (a,pdfverbose(b)) end }
implement { name = "lpdf_adddocumentshade",      arguments = two_strings, actions = function(a,b) lpdf.adddocumentshade     (a,pdfverbose(b)) end }