summaryrefslogtreecommitdiff
path: root/Master/texmf-dist/tex/context/base/node-acc.lua
blob: e684aeb7b88fe658498946b6b3eb645da6bcd302 (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
if not modules then modules = { } end modules ['node-acc'] = {
    version   = 1.001,
    comment   = "companion to node-ini.mkiv",
    author    = "Hans Hagen, PRAGMA-ADE, Hasselt NL",
    copyright = "PRAGMA ADE / ConTeXt Development Team",
    license   = "see context related readme files"
}

local nodes, node = nodes, node

local nodecodes      = nodes.nodecodes
local tasks          = nodes.tasks

local nuts           = nodes.nuts
local tonut          = nodes.tonut
local tonode         = nodes.tonode

local getid          = nuts.getid
local getfield       = nuts.getfield
local getattr        = nuts.getattr
local getlist        = nuts.getlist
local getchar        = nuts.getchar
local getnext        = nuts.getnext

local setfield       = nuts.setfield
local setattr        = nuts.setattr

local traverse_nodes = nuts.traverse
local traverse_id    = nuts.traverse_id
local copy_node      = nuts.copy
local free_nodelist  = nuts.flush_list
local insert_after   = nuts.insert_after

local new_gluespec   = nuts.pool.gluespec -- temp hack

local glue_code      = nodecodes.glue
local kern_code      = nodecodes.kern
local glyph_code     = nodecodes.glyph
local hlist_code     = nodecodes.hlist
local vlist_code     = nodecodes.vlist

local a_characters   = attributes.private("characters")

local threshold      = 65536 -- not used
local nofreplaced    = 0

-- todo: nbsp etc
-- todo: collapse kerns

-- p_id

local function injectspaces(head)
    local p, p_id
    local n = head
    while n do
        local id = getid(n)
        if id == glue_code then -- todo: check for subtype related to spacing (13/14 but most seems to be 0)
       -- if getfield(getfield(n,"spec"),"width") > 0 then -- threshold
--          if p and p_id == glyph_code then
            if p and getid(p) == glyph_code then
                local g = copy_node(p)
                local c = getfield(g,"components")
                if c then -- it happens that we copied a ligature
                    free_nodelist(c)
                    setfield(g,"components",nil)
                    setfield(g,"subtype",256)
                end
                local a = getattr(n,a_characters)
                -- local s = copy_node(getfield(n,"spec"))
                -- this will be fixed in luatex but for now a temp hack (zero test)
                local s = getfield(n,"spec")
                s = s == 0 and new_gluespec(0) or copy_node(s)
                --
                setfield(g,"char",32)
                setfield(n,"spec",s)
             -- insert_after(p,p,g)
                setfield(p,"next",g)
                setfield(g,"prev",p)
                setfield(g,"next",n)
                setfield(n,"prev",g)
                setfield(s,"width",getfield(s,"width") - getfield(g,"width"))
                if a then
                    setattr(g,a_characters,a)
                end
                setattr(s,a_characters,0)
                setattr(n,a_characters,0)
                nofreplaced = nofreplaced + 1
            end
       -- end
        elseif id == hlist_code or id == vlist_code then
            injectspaces(getlist(n),attribute)
     -- elseif id == kern_code then -- the backend already collapses
     --     local first = n
     --     while true do
     --         local nn = getnext(n)
     --         if nn and getid(nn) == kern_code then
     --          -- maybe we should delete kerns but who cares at this stage
     --             setfield(first,"kern",getfield(first,"kern") + getfield(nn,"kern")
     --             setfield(nn,"kern",0)
     --             n = nn
     --         else
     --             break
     --         end
     --     end
        end
        p_id = id
        p = n
        n = getnext(n)
    end
    return head, true -- always done anyway
end

nodes.handlers.accessibility = function(head)
    local head, done = injectspaces(tonut(head))
    return tonode(head), done
end

statistics.register("inserted spaces in output",function()
    if nofreplaced > 0 then
        return nofreplaced
    end
end)

-- todo:

-- local a_hyphenated = attributes.private('hyphenated')
--
-- local hyphenated, codes = { }, { }
--
-- local function compact(n)
--     local t = { }
--     for n in traverse_id(glyph_code,n) do
--         t[#t+1] = utfchar(getchar(n)) -- check for unicode
--     end
--     return concat(t,"")
-- end
--
-- local function injectspans(head)
--     local done = false
--     for n in traverse_nodes(tonuts(head)) do
--         local id = getid(n)
--         if id == disc then
--             local r = getfield(n,"replace")
--             local p = getfield(n,"pre")
--             if r and p then
--                 local str = compact(r)
--                 local hsh = hyphenated[str]
--                 if not hsh then
--                     hsh = #codes + 1
--                     hyphenated[str] = hsh
--                     codes[hsh] = str
--                 end
--                 setattr(n,a_hyphenated,hsh)
--                 done = true
--             end
--         elseif id == hlist_code or id == vlist_code then
--             injectspans(getlist(n))
--         end
--     end
--     return tonodes(head), done
-- end
--
-- nodes.injectspans = injectspans
--
-- tasks.appendaction("processors", "words", "nodes.injectspans")
--
-- local function injectspans(head)
--     local done = false
--     for n in traverse_nodes(tonut(head)) do
--         local id = getid(n)
--         if id == disc then
--             local a = getattr(n,a_hyphenated)
--             if a then
--                 local str = codes[a]
--                 local b = new_pdfliteral(format("/Span << /ActualText %s >> BDC", lpdf.tosixteen(str)))
--                 local e = new_pdfliteral("EMC")
--                 insert_before(head,n,b)
--                 insert_after(head,n,e)
--                 done = true
--             end
--         elseif id == hlist_code or id == vlist_code then
--             injectspans(getlist(n))
--         end
--     end
--     return tonodes(head), done
-- end