beta 2013.10.20 07:09

1 files changed, 155 insertions, 381 deletions

diff --git a/tex/context/base/typo-dir.lua b/tex/context/base/typo-dir.lua
index 7e5f8c2d3..a04028452 100644
--- a/tex/context/base/typo-dir.lua
+++ b/tex/context/base/typo-dir.lua
@@ -6,37 +6,72 @@ if not modules then modules = { } end modules ['typo-dir'] = {
     license   = "see context related readme files"
 }
 
--- todo: also use end_of_math here?
+-- When we started with this, there were some issues in luatex so we needed to take care of
+-- intereferences. Some has been improved but we stil might end up with each node having a
+-- dir property. Now, the biggest problem is that there is an official bidi algorithm but
+-- some searching on the web shows that there are many confusing aspects and therefore
+-- proposals circulate about (sometimes imcompatible ?) improvements. In the end it all boils
+-- down to the lack of willingness to tag an input source. Of course tagging of each number
+-- and fenced strip is somewhat over the top, but now it has to be captured in logic. Texies
+-- normally have no problem with tagging but we need to handle any input. So, what we have
+-- done here (over the years) is starting from what we expect to see happen, especially with
+-- respect to punctation, numbers and fences. Eventually alternative algorithms will be provides
+-- so that users can choose (the reason why suggestion sfor improvements circulate on the web
+-- is that it is non trivial to predict the expected behaviour so one hopes that the ditor
+-- and the rest of the machinery match somehow. Anyway, the fun of tex is that it has no hard
+-- coded behavior. And ... we also want to have more debugging and extras and ... so we want
+-- a flexible approach. In the end we will have:
+--
+-- = full tagging (mechanism turned off)
+-- = half tagging (the current implementation)
+-- = unicode version x interpretation (several depending on the evolution)
 
 local next, type = next, type
 local format, insert, sub, find, match = string.format, table.insert, string.sub, string.find, string.match
 local utfchar = utf.char
-
--- vertical space handler
+local formatters = string.formatters
 
 local nodes, node = nodes, node
 
-local trace_directions = false  trackers.register("typesetters.directions", function(v) trace_directions = v end)
+local trace_textdirections = false  trackers.register("typesetters.directions.text", function(v) trace_textdirections = v end)
+local trace_mathdirections = false  trackers.register("typesetters.directions.math", function(v) trace_mathdirections = v end)
+local trace_directions     = false  trackers.register("typesetters.directions",      function(v) trace_textdirections = v trace_mathdirections = v end)
+
+local report_textdirections = logs.reporter("typesetting","text directions")
+local report_mathdirections = logs.reporter("typesetting","math directions")
+
+
 
-local report_directions = logs.reporter("typesetting","directions")
 
 local traverse_id        = node.traverse_id
 local insert_node_before = node.insert_before
 local insert_node_after  = node.insert_after
 local remove_node        = nodes.remove
+local end_of_math        = nodes.end_of_math
 
-local texattribute       = tex.attribute
+local texsetattribute    = tex.setattribute
+local texsetcount        = tex.setcount
 local unsetvalue         = attributes.unsetvalue
 
+local hasbit             = number.hasbit
+
 local nodecodes          = nodes.nodecodes
 local whatcodes          = nodes.whatcodes
 local mathcodes          = nodes.mathcodes
 
 local tasks              = nodes.tasks
+local tracers            = nodes.tracers
+local setcolor           = tracers.colors.set
+local resetcolor         = tracers.colors.reset
 
 local glyph_code         = nodecodes.glyph
 local whatsit_code       = nodecodes.whatsit
 local math_code          = nodecodes.math
+local penalty_code       = nodecodes.penalty
+local kern_code          = nodecodes.kern
+local glue_code          = nodecodes.glue
+local hlist_code         = nodecodes.hlist
+local vlist_code         = nodecodes.vlist
 
 local localpar_code      = whatcodes.localpar
 local dir_code           = whatcodes.dir
@@ -45,404 +80,149 @@ local nodepool           = nodes.pool
 
 local new_textdir        = nodepool.textdir
 
-local beginmath_code     = mathcodes.beginmath
-local endmath_code       = mathcodes.endmath
-
 local fonthashes         = fonts.hashes
 local fontdata           = fonthashes.identifiers
 local fontchar           = fonthashes.characters
 
-local chardata           = characters.data
-local chardirs           = characters.directions -- maybe make a special mirror table
-
---~ Analysis by Idris:
---~
---~ 1. Assuming the reading- vs word-order distinction (bidi-char types) is governing;
---~ 2. Assuming that 'ARAB' represents an actual arabic string in raw input order, not word-order;
---~ 3. Assuming that 'BARA' represent the correct RL word order;
---~
---~ Then we have, with input: LATIN ARAB
---~
---~ \textdir TLT LATIN ARAB => LATIN BARA
---~ \textdir TRT LATIN ARAB => LATIN BARA
---~ \textdir TRT LRO LATIN ARAB => LATIN ARAB
---~ \textdir TLT LRO LATIN ARAB => LATIN ARAB
---~ \textdir TLT RLO LATIN ARAB => NITAL ARAB
---~ \textdir TRT RLO LATIN ARAB => NITAL ARAB
-
---  elseif d == "es"  then -- European Number Separator
---  elseif d == "et"  then -- European Number Terminator
---  elseif d == "cs"  then -- Common Number Separator
---  elseif d == "nsm" then -- Non-Spacing Mark
---  elseif d == "bn"  then -- Boundary Neutral
---  elseif d == "b"   then -- Paragraph Separator
---  elseif d == "s"   then -- Segment Separator
---  elseif d == "ws"  then -- Whitespace
---  elseif d == "on"  then -- Other Neutrals
-
-typesetters.directions = typesetters.directions or { }
-local directions       = typesetters.directions
-
-local a_state          = attributes.private('state')
-local a_directions     = attributes.private('directions')
-
-local skipmath         = true
-local strip            = false
-
--- todo: delayed inserts here
--- todo: get rid of local functions here
-
--- beware, math adds whatsits afterwards so that will mess things up
-
-local finish, autodir, embedded, override, done = nil, 0, 0, 0, false
-local list, glyphs = nil, false
-local finished, finidir, finipos = nil, nil, 1
-local head, current, inserted = nil, nil, nil
-
-local function finish_auto_before()
-    head, inserted = insert_node_before(head,current,new_textdir("-"..finish))
-    finished, finidir = inserted, finish
-    if trace_directions then
-        insert(list,#list,format("auto finish inserted before: %s",finish))
-        finipos = #list-1
-    end
-    finish, autodir, done = nil, 0, true
-end
+local chardirections     = characters.directions
+local charmirrors        = characters.mirrors
+local charclasses        = characters.textclasses
+
+local directions         = typesetters.directions or { }
+typesetters.directions   = directions
+
+local a_state            = attributes.private('state')
+local a_directions       = attributes.private('directions')
+local a_mathbidi         = attributes.private('mathbidi')
+
+local strip              = false
 
-local function finish_auto_after()
-    head, current = insert_node_after(head,current,new_textdir("-"..finish))
-    finished, finidir = current, finish
-    if trace_directions then
-        list[#list+1] = format("auto finish inserted after: %s",finish)
-        finipos = #list
+local s_isol             = fonts.analyzers.states.isol
+
+local variables          = interfaces.variables
+local v_global           = variables["global"]
+local v_local            = variables["local"]
+local v_on               = variables.on
+local v_yes              = variables.yes
+
+local m_enabled          = 2^6 -- 64
+local m_global           = 2^7
+local m_fences           = 2^8
+
+local handlers           = { }
+local methods            = { }
+local lastmethod         = 0
+
+local function installhandler(name,handler)
+    local method = methods[name]
+    if not method then
+        lastmethod    = lastmethod + 1
+        method        = lastmethod
+        methods[name] = method
     end
-    finish, autodir, done = nil, 0, true
+    handlers[method] = handler
+    return method
 end
 
-local function force_auto_left_before()
-    if finish then
-        finish_auto_before()
-    end
-    if embedded >= 0 then
-        finish, autodir, done = "TLT", 1, true
+directions.handlers       = handlers
+directions.installhandler = installhandler
+
+local function tomode(specification)
+    local scope = specification.scope
+    local mode
+    if scope == v_global or scope == v_on then
+        mode = m_enabled + m_global
+    elseif scope == v_local then
+        mode = m_enabled
     else
-        finish, autodir, done = "TRT", -1, true
+        return 0
     end
-    if finidir == finish then
-        head = remove_node(head,finished,true)
-        if trace_directions then
-            list[finipos] = list[finipos] .. " (deleted afterwards)"
-            insert(list,#list,format("start text dir %s (embedded: %s)",finish,embedded))
-        end
+    local method = methods[specification.method]
+    if method then
+        mode = mode + method
     else
-        head, inserted = insert_node_before(head,current,new_textdir("+"..finish))
-        if trace_directions then
-            insert(list,#list,format("start text dir %s (embedded: %s)",finish,embedded))
-        end
+        return 0
     end
+    if specification.fences == v_yes then
+        mode = mode + m_fences
+    end
+    return mode
 end
 
-local function force_auto_right_before()
-    if finish then
-        finish_auto_before()
-    end
-    if embedded <= 0 then
-        finish, autodir, done = "TRT", -1, true
-    else
-        finish, autodir, done = "TLT", 1, true
-    end
-    if finidir == finish then
-        head = remove_node(head,finished,true)
-        if trace_directions then
-            list[finipos] = list[finipos] .. " (deleted afterwards)"
-            insert(list,#list,format("start text dir %s (embedded: %s)",finish,embedded))
-        end
+local function getglobal(a)
+    return a and a > 0 and hasbit(a,m_global)
+end
+
+local function getfences(a)
+    return a and a > 0 and hasbit(a,m_fences)
+end
+
+local function getmethod(a)
+    return a and a > 0 and a % m_enabled or 0
+end
+
+directions.tomode         = tomode
+directions.getglobal      = getglobal
+directions.getfences      = getfences
+directions.getmethod      = getmethod
+directions.installhandler = installhandler
+
+-- beware: in dha we have character properties and in dua|b we have direction properties
+
+function directions.setcolor(current,direction,reversed,mirror)
+    if mirror then
+        setcolor(current,"bidi:mirrored")
+    elseif direction == "l" then
+        setcolor(current,reversed and "bidi:left:reversed" or "bidi:left:original")
+    elseif direction == "r" then
+        setcolor(current,reversed and "bidi:right:reversed" or "bidi:right:original")
     else
-        head, inserted = insert_node_before(head,current,new_textdir("+"..finish))
-        if trace_directions then
-            insert(list,#list,format("start text dir %s (embedded: %s)",finish,embedded))
-        end
+        resetcolor(current)
     end
 end
 
--- todo: use new dir functions
+function commands.getbidimode(specification)
+    context(tomode(specification)) -- hash at tex end
+end
 
-local s_isol = fonts.analyzers.states.isol
+local enabled = false
 
-function directions.process(namespace,attribute,start) -- todo: make faster
-    if not start.next then
-        return start, false
-    end
-    head, current, inserted = start, start, nil
-    finish, autodir, embedded, override, done = nil, 0, 0, 0, false
-    list, glyphs = trace_directions and { }, false
-    finished, finidir, finipos = nil, nil, 1
-    local stack, top, obsolete = { }, 0, { }
-    local lro, rlo, prevattr, inmath = false, false, 0, false
-    while current do
-        local id = current.id
-        if skipmath and id == math_code then
-            local subtype = current.subtype
-            if subtype == beginmath_code then
-                inmath = true
-            elseif subtype == endmath_code then
-                inmath = false
-            else
-                -- todo
-            end
-            current = current.next
-        elseif inmath then
-            current = current.next
-        else
-            local attr = current[attribute]
-            if attr and attr > 0 then
-             -- current[attribute] = unsetvalue -- slow, needed?
-                if attr == 1 then
-                    -- bidi parsing mode
-                elseif attr ~= prevattr then
-                    -- no pop, grouped driven (2=normal,3=lro,4=rlo)
-                    if attr == 3 then
-                        if trace_directions then
-                            list[#list+1] = format("override right -> left (lro) (bidi=%s)",attr)
-                        end
-                        lro, rlo = true, false
-                    elseif attr == 4 then
-                        if trace_directions then
-                            list[#list+1] = format("override left -> right (rlo) (bidi=%s)",attr)
-                        end
-                        lro, rlo = false, true
-                    else
-                        if trace_directions and
-                            current ~= head then list[#list+1] = format("override reset (bidi=%s)",attr)
-                        end
-                        lro, rlo = false, false
-                    end
-                    prevattr = attr
-                end
-            end
-            if id == glyph_code then
-                glyphs = true
-                if attr and attr > 0 then
-                    local char = current.char
-                    local d = chardirs[char]
-                    if rlo or override > 0 then
-                        if d == "l" then
-                            if trace_directions then
-                                list[#list+1] = format("char %s (%s / U+%04X) of class %s overidden to r (bidi=%s)",utfchar(char),char,char,d,attr)
-                            end
-                            d = "r"
-                        elseif trace_directions then
-                            if d == "lro" or d == "rlo" or d == "pdf" then -- else side effects on terminal
-                                list[#list+1] = format("override char of class %s (bidi=%s)",d,attr)
-                            else -- todo: rle lre
-                                list[#list+1] = format("char %s (%s / U+%04X) of class %s (bidi=%s)",utfchar(char),char,char,d,attr)
-                            end
-                        end
-                    elseif lro or override < 0 then
-                        if d == "r" or d == "al" then
-                            current[a_state] = s_isol -- maybe better have a special bidi attr value -> override (9) -> todo
-                            if trace_directions then
-                                list[#list+1] = format("char %s (%s / U+%04X) of class %s overidden to l (bidi=%s) (state=isol)",utfchar(char),char,char,d,attr)
-                            end
-                            d = "l"
-                        elseif trace_directions then
-                            if d == "lro" or d == "rlo" or d == "pdf" then -- else side effects on terminal
-                                list[#list+1] = format("override char of class %s (bidi=%s)",d,attr)
-                            else -- todo: rle lre
-                                list[#list+1] = format("char %s (%s / U+%04X) of class %s (bidi=%s)",utfchar(char),char,char,d,attr)
-                            end
-                        end
-                    elseif trace_directions then
-                        if d == "lro" or d == "rlo" or d == "pdf" then -- else side effects on terminal
-                            list[#list+1] = format("override char of class %s (bidi=%s)",d,attr)
-                        else -- todo: rle lre
-                            list[#list+1] = format("char %s (%s / U+%04X) of class %s (bidi=%s)",utfchar(char),char,char,d,attr)
-                        end
-                    end
-                    if d == "on" then
-                        local mirror = chardata[char].mirror -- maybe make a special mirror table
-                        if mirror and fontchar[current.font][mirror] then
-                            -- todo: set attribute
-                            if autodir < 0 then
-                                current.char = mirror
-                                done = true
-                            --~ elseif left or autodir > 0 then
-                            --~     if not is_right(current.prev) then
-                            --~         current.char = mirror
-                            --~         done = true
-                            --~     end
-                            end
-                        end
-                    elseif d == "l" or d == "en" then -- european number
-                        if autodir <= 0 then -- could be option
-                            force_auto_left_before()
-                        end
-                    elseif d == "r" or d == "al" then -- arabic number
-                        if autodir >= 0 then
-                            force_auto_right_before()
-                        end
-                    elseif d == "an" then -- arabic number
-                        -- actually this is language dependent ...
---                         if autodir <= 0 then
---                             force_auto_left_before()
---                         end
-                        if autodir >= 0 then
-                            force_auto_right_before()
-                        end
-                    elseif d == "lro" then -- Left-to-Right Override -> right becomes left
-                        if trace_directions then
-                            list[#list+1] = "override right -> left"
-                        end
-                        top = top + 1
-                        stack[top] = { override, embedded }
-                        override = -1
-                        obsolete[#obsolete+1] = current
-                    elseif d == "rlo" then -- Right-to-Left Override -> left becomes right
-                        if trace_directions then
-                            list[#list+1] = "override left -> right"
-                        end
-                        top = top + 1
-                        stack[top] = { override, embedded }
-                        override = 1
-                        obsolete[#obsolete+1] = current
-                    elseif d == "lre" then -- Left-to-Right Embedding -> TLT
-                        if trace_directions then
-                            list[#list+1] = "embedding left -> right"
-                        end
-                        top = top + 1
-                        stack[top] = { override, embedded }
-                        embedded = 1
-                        obsolete[#obsolete+1] = current
-                    elseif d == "rle" then -- Right-to-Left Embedding -> TRT
-                        if trace_directions then
-                            list[#list+1] = "embedding right -> left"
-                        end
-                        top = top + 1
-                        stack[top] = { override, embedded }
-                        embedded = -1 -- was 1
-                        obsolete[#obsolete+1] = current
-                    elseif d == "pdf" then -- Pop Directional Format
-                    --  override = 0
-                        if top > 0 then
-                            local s = stack[top]
-                            override, embedded = s[1], s[2]
-                            top = top - 1
-                            if trace_directions then
-                                list[#list+1] = format("state: override: %s, embedded: %s, autodir: %s",override,embedded,autodir)
-                            end
-                        else
-                            if trace_directions then
-                                list[#list+1] = "pop (error, too many pops)"
-                            end
-                        end
-                        obsolete[#obsolete+1] = current
-                    end
-                elseif trace_directions then
-                    local char = current.char
-                    local d = chardirs[char]
-                    list[#list+1] = format("char %s (%s / U+%04X) of class %s (no bidi)",utfchar(char),char,char,d or "?")
-                end
-            elseif id == whatsit_code then
-                if finish then
-                    finish_auto_before()
-                end
-                local subtype = current.subtype
-                if subtype == localpar_code then
-                    local dir = current.dir
-                    local d = sub(dir,2,2)
-                    if d == 'R' then -- find(dir,".R.") / dir == "TRT"
-                        autodir = -1
-                    else
-                        autodir = 1
-                    end
-                 -- embedded = autodir
-                    if trace_directions then
-                        list[#list+1] = format("pardir %s",dir)
-                    end
-                elseif subtype == dir_code then
-                    local dir = current.dir
-                 -- local sign = sub(dir,1,1)
-                 -- local dire = sub(dir,3,3)
-                    local sign, dire = match(dir,"^(.).(.)")
-                    if dire == "R" then
-                        if sign == "+" then
-                            finish, autodir = "TRT", -1
-                        else
-                            finish, autodir = nil, 0
-                        end
-                    else
-                        if sign == "+" then
-                            finish, autodir = "TLT", 1
-                        else
-                            finish, autodir = nil, 0
-                        end
-                    end
-                    if trace_directions then
-                        list[#list+1] = format("textdir %s",dir)
-                    end
-                end
-            else
-                if trace_directions then
-                    list[#list+1] = format("node %s (subtype %s)",nodecodes[id],current.subtype)
-                end
-                if finish then
-                    finish_auto_before()
-                end
-            end
-            local cn = current.next
-            if not cn then
-                if finish then
-                    finish_auto_after()
-                end
-            end
-            current = cn
-        end
+local starttiming = statistics.starttiming
+local stoptiming  = statistics.stoptiming
+
+function directions.handler(head) -- ,_,_,_,direction) -- nodes not nuts | 5th arg is direction
+    if not head.next then
+        return head, false
     end
-    if trace_directions and glyphs then
-        report_directions("start log")
-        for i=1,#list do
-            report_directions("%02i: %s",i,list[i])
-        end
-        report_directions("stop log")
+    local attr = head[a_directions]
+    if not attr or attr == 0 then
+        return head, false
     end
-    if done and strip then
-        local n = #obsolete
-        if n > 0 then
-            for i=1,n do
-                remove_node(head,obsolete[i],true)
-            end
-            report_directions("%s character nodes removed",n)
-        end
+    local method  = getmethod(attr)
+    local handler = handlers[method]
+    if not handler then
+        return head, false
     end
+    starttiming(directions)
+    local head, done = handler(head)
+    stoptiming(directions)
     return head, done
 end
 
---~         local function is_right(n) -- keep !
---~             if n then
---~                 local id = n.id
---~                 if id == glyph_code then
---~                     local attr = n[attribute]
---~                     if attr and attr > 0 then
---~                         local d = chardirs[n.char]
---~                         if d == "r" or d == "al" then -- override
---~                             return true
---~                         end
---~                     end
---~                 end
---~             end
---~             return false
---~         end
-
---~ function directions.enable()
---~     tasks.enableaction("processors","directions.handler")
---~ end
+statistics.register("text directions", function()
+    if enabled then
+        return statistics.elapsedseconds(directions)
+    end
+end)
 
-local enabled = false
+-- function directions.enable()
+--     tasks.enableaction("processors","directions.handler")
+-- end
 
 function directions.set(n) -- todo: names and numbers
     if not enabled then
-        if trace_directions then
-            report_breakpoints("enabling directions handler")
+        if trace_textdirections then
+            report_textdirections("enabling directions handler")
         end
         tasks.enableaction("processors","typesetters.directions.handler")
         enabled = true
@@ -451,13 +231,7 @@ function directions.set(n) -- todo: names and numbers
         n = unsetvalue
         -- maybe tracing
     end
-    texattribute[a_directions] = n
+    texsetattribute(a_directions,n)
 end
 
 commands.setdirection = directions.set
-
-directions.handler = nodes.installattributehandler {
-    name = "directions",
-    namespace = directions,
-    processor = directions.process,
-}