if not modules then modules = { } end modules ['font-otf'] = {
    version   = 1.001,
    comment   = "companion to font-ini.mkiv",
    author    = "Hans Hagen, PRAGMA-ADE, Hasselt NL",
    copyright = "PRAGMA ADE / ConTeXt Development Team",
    license   = "see context related readme files"
}

-- langs -> languages enz
-- anchor_classes vs kernclasses
-- modification/creationtime in subfont is runtime dus zinloos
-- to_table -> totable
-- ascent descent

-- to be checked: combinations like:
--
-- current="ABCD" with [A]=nothing, [BC]=ligature, [D]=single (applied to result of BC so funny index)
--
-- unlikely but possible

-- more checking against low level calls of functions

local utfbyte = utf.byte
local gmatch, gsub, find, match, lower, strip = string.gmatch, string.gsub, string.find, string.match, string.lower, string.strip
local type, next, tonumber, tostring = type, next, tonumber, tostring
local abs = math.abs
local reversed, concat, insert, remove, sortedkeys = table.reversed, table.concat, table.insert, table.remove, table.sortedkeys
local ioflush = io.flush
local fastcopy, tohash, derivetable, copy = table.fastcopy, table.tohash, table.derive, table.copy
local formatters = string.formatters
local P, R, S, C, Ct, lpegmatch = lpeg.P, lpeg.R, lpeg.S, lpeg.C, lpeg.Ct, lpeg.match

local setmetatableindex  = table.setmetatableindex
local allocate           = utilities.storage.allocate
local registertracker    = trackers.register
local registerdirective  = directives.register
local starttiming        = statistics.starttiming
local stoptiming         = statistics.stoptiming
local elapsedtime        = statistics.elapsedtime
local findbinfile        = resolvers.findbinfile

local trace_private      = false  registertracker("otf.private",        function(v) trace_private   = v end)
local trace_subfonts     = false  registertracker("otf.subfonts",       function(v) trace_subfonts  = v end)
local trace_loading      = false  registertracker("otf.loading",        function(v) trace_loading   = v end)
local trace_features     = false  registertracker("otf.features",       function(v) trace_features  = v end)
local trace_dynamics     = false  registertracker("otf.dynamics",       function(v) trace_dynamics  = v end)
local trace_sequences    = false  registertracker("otf.sequences",      function(v) trace_sequences = v end)
local trace_markwidth    = false  registertracker("otf.markwidth",      function(v) trace_markwidth = v end)
local trace_defining     = false  registertracker("fonts.defining",     function(v) trace_defining  = v end)

local compact_lookups    = true   registertracker("otf.compactlookups", function(v) compact_lookups = v end)
local purge_names        = true   registertracker("otf.purgenames",     function(v) purge_names     = v end)

local report_otf         = logs.reporter("fonts","otf loading")

local fonts              = fonts
local otf                = fonts.handlers.otf

otf.glists               = { "gsub", "gpos" }

otf.version              = 2.825 -- beware: also sync font-mis.lua and in mtx-fonts
otf.cache                = containers.define("fonts", "otf", otf.version, true)

local hashes             = fonts.hashes
local definers           = fonts.definers
local readers            = fonts.readers
local constructors       = fonts.constructors

local fontdata           = hashes     and hashes.identifiers
local chardata           = characters and characters.data -- not used

local otffeatures        = constructors.newfeatures("otf")
local registerotffeature = otffeatures.register

local enhancers          = allocate()
otf.enhancers            = enhancers
local patches            = { }
enhancers.patches        = patches

local forceload          = false
local cleanup            = 0     -- mk: 0=885M 1=765M 2=735M (regular run 730M)
local packdata           = true
local syncspace          = true
local forcenotdef        = false
local includesubfonts    = false
local overloadkerns      = false -- experiment

local applyruntimefixes  = fonts.treatments and fonts.treatments.applyfixes

local wildcard           = "*"
local default            = "dflt"

local fontloader         = fontloader
local open_font          = fontloader.open
local close_font         = fontloader.close
local font_fields        = fontloader.fields
local apply_featurefile  = fontloader.apply_featurefile

local mainfields         = nil
local glyphfields        = nil -- not used yet

local formats            = fonts.formats

formats.otf              = "opentype"
formats.ttf              = "truetype"
formats.ttc              = "truetype"
formats.dfont            = "truetype"

registerdirective("fonts.otf.loader.cleanup",       function(v) cleanup       = tonumber(v) or (v and 1) or 0 end)
registerdirective("fonts.otf.loader.force",         function(v) forceload     = v end)
registerdirective("fonts.otf.loader.pack",          function(v) packdata      = v end)
registerdirective("fonts.otf.loader.syncspace",     function(v) syncspace     = v end)
registerdirective("fonts.otf.loader.forcenotdef",   function(v) forcenotdef   = v end)
registerdirective("fonts.otf.loader.overloadkerns", function(v) overloadkerns = v end)
-----------------("fonts.otf.loader.alldimensions", function(v) alldimensions = v end)

function otf.fileformat(filename)
    local leader = lower(io.loadchunk(filename,4))
    local suffix = lower(file.suffix(filename))
    if leader == "otto" then
        return formats.otf, suffix == "otf"
    elseif leader == "ttcf" then
        return formats.ttc, suffix == "ttc"
 -- elseif leader == "true" then
 --     return formats.ttf, suffix == "ttf"
    elseif suffix == "ttc" then
        return formats.ttc, true
    elseif suffix == "dfont" then
        return formats.dfont, true
    else
        return formats.ttf, suffix == "ttf"
    end
end

-- local function otf_format(filename)
--  -- return formats[lower(file.suffix(filename))]
-- end

local function otf_format(filename)
    local format, okay = otf.fileformat(filename)
    if not okay then
        report_otf("font %a is actually an %a file",filename,format)
    end
    return format
end

local function load_featurefile(raw,featurefile)
    if featurefile and featurefile ~= "" then
        if trace_loading then
            report_otf("using featurefile %a", featurefile)
        end
        apply_featurefile(raw, featurefile)
    end
end

local function showfeatureorder(rawdata,filename)
    local sequences = rawdata.resources.sequences
    if sequences and #sequences > 0 then
        if trace_loading then
            report_otf("font %a has %s sequences",filename,#sequences)
            report_otf(" ")
        end
        for nos=1,#sequences do
            local sequence  = sequences[nos]
            local typ       = sequence.type      or "no-type"
            local name      = sequence.name      or "no-name"
            local subtables = sequence.subtables or { "no-subtables" }
            local features  = sequence.features
            if trace_loading then
                report_otf("%3i  %-15s  %-20s  [% t]",nos,name,typ,subtables)
            end
            if features then
                for feature, scripts in next, features do
                    local tt = { }
                    if type(scripts) == "table" then
                        for script, languages in next, scripts do
                            local ttt = { }
                            for language, _ in next, languages do
                                ttt[#ttt+1] = language
                            end
                            tt[#tt+1] = formatters["[%s: % t]"](script,ttt)
                        end
                        if trace_loading then
                            report_otf("       %s: % t",feature,tt)
                        end
                    else
                        if trace_loading then
                            report_otf("       %s: %S",feature,scripts)
                        end
                    end
                end
            end
        end
        if trace_loading then
            report_otf("\n")
        end
    elseif trace_loading then
        report_otf("font %a has no sequences",filename)
    end
end

--[[ldx--
<p>We start with a lot of tables and related functions.</p>
--ldx]]--

local valid_fields = table.tohash {
 -- "anchor_classes",
    "ascent",
 -- "cache_version",
    "cidinfo",
    "copyright",
 -- "creationtime",
    "descent",
    "design_range_bottom",
    "design_range_top",
    "design_size",
    "encodingchanged",
    "extrema_bound",
    "familyname",
    "fontname",
    "fontstyle_id",
    "fontstyle_name",
    "fullname",
 -- "glyphs",
    "hasvmetrics",
 -- "head_optimized_for_cleartype",
    "horiz_base",
    "issans",
    "isserif",
    "italicangle",
 -- "kerns",
 -- "lookups",
    "macstyle",
 -- "modificationtime",
    "notdef_loc",
    "onlybitmaps",
    "origname",
    "os2_version",
    "pfminfo",
 -- "private",
    "serifcheck",
    "sfd_version",
 -- "size",
    "strokedfont",
    "strokewidth",
 -- "subfonts",
    "table_version",
 -- "tables",
 -- "ttf_tab_saved",
    "ttf_tables",
    "uni_interp",
    "uniqueid",
    "units_per_em",
    "upos",
    "use_typo_metrics",
    "uwidth",
    "validation_state",
    "version",
    "vert_base",
    "weight",
    "weight_width_slope_only",
 -- "xuid",
 -- "truetype", -- maybe as check
}

local ordered_enhancers = {
    "prepare tables",

    "prepare glyphs",
    "prepare lookups",

    "analyze glyphs",
    "analyze math",

 -- "prepare tounicode",

    "reorganize lookups",
    "reorganize mark classes",
    "reorganize anchor classes",

    "reorganize glyph kerns",
    "reorganize glyph lookups",
    "reorganize glyph anchors",

    "merge kern classes",

    "reorganize features",
    "reorganize subtables",

    "check glyphs",
    "check metadata",

    "prepare tounicode",

    "check encoding", -- moved
    "add duplicates",

    "expand lookups", -- a temp hack awaiting the lua loader

    "check extra features", -- after metadata and duplicates

    "cleanup tables",

    "compact lookups",
    "purge names",
}

--[[ldx--
<p>Here we go.</p>
--ldx]]--

local actions  = allocate()
local before   = allocate()
local after    = allocate()

patches.before = before
patches.after  = after

local function enhance(name,data,filename,raw)
    local enhancer = actions[name]
    if enhancer then
        if trace_loading then
            report_otf("apply enhancement %a to file %a",name,filename)
            ioflush()
        end
        enhancer(data,filename,raw)
    else
        -- no message as we can have private ones
    end
end

function enhancers.apply(data,filename,raw)
    local basename = file.basename(lower(filename))
    if trace_loading then
        report_otf("%s enhancing file %a","start",filename)
    end
    ioflush() -- we want instant messages
    for e=1,#ordered_enhancers do
        local enhancer = ordered_enhancers[e]
        local b = before[enhancer]
        if b then
            for pattern, action in next, b do
                if find(basename,pattern) then
                    action(data,filename,raw)
                end
            end
        end
        enhance(enhancer,data,filename,raw)
        local a = after[enhancer]
        if a then
            for pattern, action in next, a do
                if find(basename,pattern) then
                    action(data,filename,raw)
                end
            end
        end
        ioflush() -- we want instant messages
    end
    if trace_loading then
        report_otf("%s enhancing file %a","stop",filename)
    end
    ioflush() -- we want instant messages
end

-- patches.register("before","migrate metadata","cambria",function() end)

function patches.register(what,where,pattern,action)
    local pw = patches[what]
    if pw then
        local ww = pw[where]
        if ww then
            ww[pattern] = action
        else
            pw[where] = { [pattern] = action}
        end
    end
end

function patches.report(fmt,...)
    if trace_loading then
        report_otf("patching: %s",formatters[fmt](...))
    end
end

function enhancers.register(what,action) -- only already registered can be overloaded
    actions[what] = action
end

function otf.load(filename,sub,featurefile) -- second argument (format) is gone !
    local base = file.basename(file.removesuffix(filename))
    local name = file.removesuffix(base)
    local attr = lfs.attributes(filename)
    local size = attr and attr.size or 0
    local time = attr and attr.modification or 0
    if featurefile then
        name = name .. "@" .. file.removesuffix(file.basename(featurefile))
    end
    -- or: sub = tonumber(sub)
    if sub == "" then
        sub = false
    end
    local hash = name
    if sub then
        hash = hash .. "-" .. sub
    end
    hash = containers.cleanname(hash)
    local featurefiles
    if featurefile then
        featurefiles = { }
        for s in gmatch(featurefile,"[^,]+") do
            local name = resolvers.findfile(file.addsuffix(s,'fea'),'fea') or ""
            if name == "" then
                report_otf("loading error, no featurefile %a",s)
            else
                local attr = lfs.attributes(name)
                featurefiles[#featurefiles+1] = {
                    name = name,
                    size = attr and attr.size or 0,
                    time = attr and attr.modification or 0,
                }
            end
        end
        if #featurefiles == 0 then
            featurefiles = nil
        end
    end
    local data = containers.read(otf.cache,hash)
    local reload = not data or data.size ~= size or data.time ~= time
    if forceload then
        report_otf("forced reload of %a due to hard coded flag",filename)
        reload = true
    end
    if not reload then
        local featuredata = data.featuredata
        if featurefiles then
            if not featuredata or #featuredata ~= #featurefiles then
                reload = true
            else
                for i=1,#featurefiles do
                    local fi, fd = featurefiles[i], featuredata[i]
                    if fi.name ~= fd.name or fi.size ~= fd.size or fi.time ~= fd.time then
                        reload = true
                        break
                    end
                end
            end
        elseif featuredata then
            reload = true
        end
        if reload then
           report_otf("loading: forced reload due to changed featurefile specification %a",featurefile)
        end
     end
     if reload then
        starttiming("fontloader")
        report_otf("loading %a, hash %a",filename,hash)
        local fontdata, messages
        if sub then
            fontdata, messages = open_font(filename,sub)
        else
            fontdata, messages = open_font(filename)
        end
        if fontdata then
            mainfields = mainfields or (font_fields and font_fields(fontdata))
        end
        if trace_loading and messages and #messages > 0 then
            if type(messages) == "string" then
                report_otf("warning: %s",messages)
            else
                for m=1,#messages do
                    report_otf("warning: %S",messages[m])
                end
            end
        else
            report_otf("loading done")
        end
        if fontdata then
            if featurefiles then
                for i=1,#featurefiles do
                    load_featurefile(fontdata,featurefiles[i].name)
                end
            end
            local unicodes = {
                -- names to unicodes
            }
            local splitter = lpeg.splitter(" ",unicodes)
            data = {
                size        = size,
                time        = time,
                subfont     = sub,
                format      = otf_format(filename),
                featuredata = featurefiles,
                resources   = {
                    filename = resolvers.unresolve(filename), -- no shortcut
                    version  = otf.version,
                    creator  = "context mkiv",
                    unicodes = unicodes,
                    indices  = {
                        -- index to unicodes
                    },
                    duplicates = {
                        -- alternative unicodes
                    },
                    variants = {
                        -- alternative unicodes (variants)
                    },
                    lookuptypes = {
                    },
                },
                warnings    = {
                },
                metadata    = {
                    -- raw metadata, not to be used
                },
                properties   = {
                    -- normalized metadata
                },
                descriptions = {
                },
                goodies = {
                },
                helpers = { -- might go away
                    tounicodelist  = splitter,
                    tounicodetable = Ct(splitter),
                },
            }
            report_otf("file size: %s", size)
            enhancers.apply(data,filename,fontdata)
            local packtime = { }
            if packdata then
                if cleanup > 0 then
                    collectgarbage("collect")
                end
                starttiming(packtime)
                enhance("pack",data,filename,nil)
                stoptiming(packtime)
            end
            report_otf("saving %a in cache",filename)
            data = containers.write(otf.cache, hash, data)
            if cleanup > 1 then
                collectgarbage("collect")
            end
            stoptiming("fontloader")
            if elapsedtime then -- not in generic
                report_otf("loading, optimizing, packing and caching time %s, pack time %s",
                    elapsedtime("fontloader"),packdata and elapsedtime(packtime) or 0)
            end
            close_font(fontdata) -- free memory
            if cleanup > 3 then
                collectgarbage("collect")
            end
            data = containers.read(otf.cache, hash) -- this frees the old table and load the sparse one
            if cleanup > 2 then
                collectgarbage("collect")
            end
        else
            stoptiming("fontloader")
            data = nil
            report_otf("loading failed due to read error")
        end
    end
    if data then
        if trace_defining then
            report_otf("loading from cache using hash %a",hash)
        end
        enhance("unpack",data,filename,nil,false)
        --
        local resources  = data.resources
        local lookuptags = resources.lookuptags
        local unicodes   = resources.unicodes
        if not lookuptags then
            lookuptags = { }
            resources.lookuptags = lookuptags
        end
        setmetatableindex(lookuptags,function(t,k)
            local v = type(k) == "number" and ("lookup " .. k) or k
            t[k] = v
            return v
        end)
        if not unicodes then
            unicodes = { }
            resources.unicodes = unicodes
            setmetatableindex(unicodes,function(t,k)
                -- use rawget when no table has to be built
                setmetatableindex(unicodes,nil)
                for u, d in next, data.descriptions do
                    local n = d.name
                    if n then
                        t[n] = u
                     -- report_otf("accessing known name %a",k)
                    else
                     -- report_otf("accessing unknown name %a",k)
                    end
                end
                return rawget(t,k)
            end)
        end
        constructors.addcoreunicodes(unicodes) -- do we really need this?
        --
        if applyruntimefixes then
            applyruntimefixes(filename,data)
        end
        enhance("add dimensions",data,filename,nil,false)
        if trace_sequences then
            showfeatureorder(data,filename)
        end
    end
    return data
end

local mt = {
    __index = function(t,k) -- maybe set it
        if k == "height" then
            local ht = t.boundingbox[4]
            return ht < 0 and 0 or ht
        elseif k == "depth" then
            local dp = -t.boundingbox[2]
            return dp < 0 and 0 or dp
        elseif k == "width" then
            return 0
        elseif k == "name" then -- or maybe uni*
            return forcenotdef and ".notdef"
        end
    end
}

actions["prepare tables"] = function(data,filename,raw)
    data.properties.hasitalics = false
end

actions["add dimensions"] = function(data,filename)
    -- todo: forget about the width if it's the defaultwidth (saves mem)
    -- we could also build the marks hash here (instead of storing it)
    if data then
        local descriptions  = data.descriptions
        local resources     = data.resources
        local defaultwidth  = resources.defaultwidth  or 0
        local defaultheight = resources.defaultheight or 0
        local defaultdepth  = resources.defaultdepth  or 0
        local basename      = trace_markwidth and file.basename(filename)
        for _, d in next, descriptions do
            local bb, wd = d.boundingbox, d.width
            if not wd then
                -- or bb?
                d.width = defaultwidth
            elseif trace_markwidth and wd ~= 0 and d.class == "mark" then
                report_otf("mark %a with width %b found in %a",d.name or "<noname>",wd,basename)
             -- d.width  = -wd
            end
            if bb then
                local ht =  bb[4]
                local dp = -bb[2]
             -- if alldimensions then
             --     if ht ~= 0 then
             --         d.height = ht
             --     end
             --     if dp ~= 0 then
             --         d.depth  = dp
             --     end
             -- else
                    if ht == 0 or ht < 0 then
                        -- not set
                    else
                        d.height = ht
                    end
                    if dp == 0 or dp < 0 then
                        -- not set
                    else
                        d.depth  = dp
                    end
             -- end
            end
        end
    end
end

local function somecopy(old) -- fast one
    if old then
        local new = { }
        if type(old) == "table" then
            for k, v in next, old do
                if k == "glyphs" then
                    -- skip
                elseif type(v) == "table" then
                    new[k] = somecopy(v)
                else
                    new[k] = v
                end
            end
        else
            for i=1,#mainfields do
                local k = mainfields[i]
                local v = old[k]
                if k == "glyphs" then
                    -- skip
                elseif type(v) == "table" then
                    new[k] = somecopy(v)
                else
                    new[k] = v
                end
            end
        end
        return new
    else
        return { }
    end
end

-- not setting hasitalics and class (when nil) during table construction can save some mem

actions["prepare glyphs"] = function(data,filename,raw)
    local rawglyphs    = raw.glyphs
    local rawsubfonts  = raw.subfonts
    local rawcidinfo   = raw.cidinfo
    local criterium    = constructors.privateoffset
    local private      = criterium
    local resources    = data.resources
    local metadata     = data.metadata
    local properties   = data.properties
    local descriptions = data.descriptions
    local unicodes     = resources.unicodes -- name to unicode
    local indices      = resources.indices  -- index to unicode
    local duplicates   = resources.duplicates
    local variants     = resources.variants
    local notdefindex  = -1

    if rawsubfonts then

        metadata.subfonts  = includesubfonts and { }
        properties.cidinfo = rawcidinfo

        if rawcidinfo.registry then
            local cidmap = fonts.cid.getmap(rawcidinfo)
            if cidmap then
                rawcidinfo.usedname = cidmap.usedname
                local nofnames    = 0
                local nofunicodes = 0
                local cidunicodes = cidmap.unicodes
                local cidnames    = cidmap.names
                local cidtotal    = 0
                local unique      = trace_subfonts and { }
                for cidindex=1,#rawsubfonts do
                    local subfont   = rawsubfonts[cidindex]
                    local cidglyphs = subfont.glyphs
                    if includesubfonts then
                        metadata.subfonts[cidindex] = somecopy(subfont)
                    end
                    local cidcnt = subfont.glyphcnt
                    local cidmin = subfont.glyphmin
                    local cidmax = subfont.glyphmax
                    local notdef = (tonumber(raw.table_version) or 0) > 0.4 and subfont.notdef_loc or -1
                    if notdeffound == -1 and notdef >= 0 then
                        notdeffound = notdef
                    end
                    if trace_subfonts then
                        local cidtot = cidmax - cidmin + 1
                        cidtotal = cidtotal + cidtot
                        report_otf("subfont: %i, min: %i, max: %i, cnt: %i, n: %i",cidindex,cidmin,cidmax,cidtot,cidcnt)
                    end
                    if cidcnt > 0 then
                        for index=cidmin,cidmax do
                            local glyph = cidglyphs[index]
                            if glyph then
                                if trace_subfonts then
                                    unique[index] = true
                                end
                                local unicode = glyph.unicode
                                if     unicode >= 0x00E000 and unicode <= 0x00F8FF then
                                    unicode = -1
                                elseif unicode >= 0x0F0000 and unicode <= 0x0FFFFD then
                                    unicode = -1
                                elseif unicode >= 0x100000 and unicode <= 0x10FFFD then
                                    unicode = -1
                                end
                                local name = glyph.name or cidnames[index]
                                if not unicode or unicode == -1 then -- or unicode >= criterium then
                                    unicode = cidunicodes[index]
                                end
                                if unicode and descriptions[unicode] then
                                    if trace_private then
                                        report_otf("preventing glyph %a at index %H to overload unicode %U",name or "noname",index,unicode)
                                    end
                                    unicode = -1
                                end
                                if not unicode or unicode == -1 then -- or unicode >= criterium then
                                    if not name then
                                        name = formatters["u%06X.ctx"](private)
                                    end
                                    unicode = private
                                    unicodes[name] = private
                                    if trace_private then
                                        report_otf("glyph %a at index %H is moved to private unicode slot %U",name,index,private)
                                    end
                                    private  = private + 1
                                    nofnames = nofnames + 1
                                else
                                 -- if unicode > criterium then
                                 --     local taken = descriptions[unicode]
                                 --     if taken then
                                 --         private = private + 1
                                 --         descriptions[private] = taken
                                 --         unicodes[taken.name] = private
                                 --         indices[taken.index] = private
                                 --         if trace_private then
                                 --             report_otf("slot %U is moved to %U due to private in font",unicode)
                                 --         end
                                 --     end
                                 -- end
                                    if not name then
                                        name = formatters["u%06X.ctx"](unicode)
                                    end
                                    unicodes[name] = unicode
                                    nofunicodes = nofunicodes + 1
                                end
                                indices[index] = unicode -- each index is unique (at least now)
                                local description = {
                                 -- width       = glyph.width,
                                    boundingbox = glyph.boundingbox,
                                 -- name        = glyph.name or name or "unknown", -- uniXXXX
                                    name        = name or "unknown", -- uniXXXX
                                 -- cidindex    = cidindex,
                                    index       = index,
                                    glyph       = glyph,
                                }
                                descriptions[unicode] = description
                                local altuni = glyph.altuni
                                if altuni then
                                 -- local d
                                    for i=1,#altuni do
                                        local a = altuni[i]
                                        local u = a.unicode
                                        if u ~= unicode then
                                            local v = a.variant
                                            if v then
                                                -- tricky: no addition to d? needs checking but in practice such dups are either very simple
                                                -- shapes or e.g cjk with not that many features
                                                local vv = variants[v]
                                                if vv then
                                                    vv[u] = unicode
                                                else -- xits-math has some:
                                                    vv = { [u] = unicode }
                                                    variants[v] = vv
                                                end
                                         -- elseif d then
                                         --     d[#d+1] = u
                                         -- else
                                         --     d = { u }
                                            end
                                        end
                                    end
                                 -- if d then
                                 --     duplicates[unicode] = d -- is this needed ?
                                 -- end
                                end
                            end
                        end
                    else
                        report_otf("potential problem: no glyphs found in subfont %i",cidindex)
                    end
                end
                if trace_subfonts then
                    report_otf("nofglyphs: %i, unique: %i",cidtotal,table.count(unique))
                end
                if trace_loading then
                    report_otf("cid font remapped, %s unicode points, %s symbolic names, %s glyphs",nofunicodes, nofnames, nofunicodes+nofnames)
                end
            elseif trace_loading then
                report_otf("unable to remap cid font, missing cid file for %a",filename)
            end
        elseif trace_loading then
            report_otf("font %a has no glyphs",filename)
        end

    else

        local cnt = raw.glyphcnt or 0
        local min = raw.glyphmin or 0
        local max = raw.glyphmax or (raw.glyphcnt - 1)
        notdeffound = (tonumber(raw.table_version) or 0) > 0.4 and raw.notdef_loc or -1
        if cnt > 0 then
            for index=min,max do
                local glyph = rawglyphs[index]
                if glyph then
                    local unicode = glyph.unicode
                    local name    = glyph.name
                    if not unicode or unicode == -1 then -- or unicode >= criterium then
                        unicode = private
                        unicodes[name] = private
                        if trace_private then
                            report_otf("glyph %a at index %H is moved to private unicode slot %U",name,index,private)
                        end
                        private = private + 1
                    else
                        -- We have a font that uses and exposes the private area. As this is rather unreliable it's
                        -- advised no to trust slots here (better use glyphnames). Anyway, we need a double check:
                        -- we need to move already moved entries and we also need to bump the next private to after
                        -- the (currently) last slot. This could leave us with a hole but we have holes anyway.
                        if unicode > criterium then
                            -- \definedfont[file:HANBatang-LVT.ttf] \fontchar{uF0135} \char"F0135
                            local taken = descriptions[unicode]
                            if taken then
                                if unicode >= private then
                                    private = unicode + 1 -- restart private (so we can have mixed now)
                                else
                                    private = private + 1 -- move on
                                end
                                descriptions[private] = taken
                                unicodes[taken.name] = private
                                indices[taken.index] = private
                                if trace_private then
                                    report_otf("slot %U is moved to %U due to private in font",unicode)
                                end
                            else
                                if unicode >= private then
                                    private = unicode + 1 -- restart (so we can have mixed now)
                                end
                            end
                        end
                        unicodes[name] = unicode
                    end
                    indices[index] = unicode
                 -- if not name then
                 --     name = formatters["u%06X"](unicode) -- u%06X.ctx
                 -- end
                    descriptions[unicode] = {
                     -- width       = glyph.width,
                        boundingbox = glyph.boundingbox,
                        name        = name,
                        index       = index,
                        glyph       = glyph,
                    }
                    local altuni = glyph.altuni
                    if altuni then
                     -- local d
                        for i=1,#altuni do
                            local a = altuni[i]
                            local u = a.unicode
                            if u ~= unicode then
                                local v = a.variant
                                if v then
                                    -- tricky: no addition to d? needs checking but in practice such dups are either very simple
                                    -- shapes or e.g cjk with not that many features
                                    local vv = variants[v]
                                    if vv then
                                        vv[u] = unicode
                                    else -- xits-math has some:
                                        vv = { [u] = unicode }
                                        variants[v] = vv
                                    end
                             -- elseif d then
                             --     d[#d+1] = u
                             -- else
                             --     d = { u }
                                end
                            end
                        end
                     -- if d then
                     --     duplicates[unicode] = d -- is this needed ?
                     -- end
                    end
                else
                    report_otf("potential problem: glyph %U is used but empty",index)
                end
            end
        else
            report_otf("potential problem: no glyphs found")
        end

    end

    if notdeffound == -1 then
        report_otf("warning: no .notdef found in %a",filename)
    elseif notdeffound ~= 0 then
        report_otf("warning: .notdef found at position %a in %a",notdeffound,filename)
    end
    metadata.notdef = notdeffound

    resources.private = private

end

-- the next one is still messy but will get better when we have
-- flattened map/enc tables in the font loader

-- the next one is not using a valid base for unicode privates
--
-- PsuedoEncodeUnencoded(EncMap *map,struct ttfinfo *info)

actions["check encoding"] = function(data,filename,raw)
    local descriptions = data.descriptions
    local resources    = data.resources
    local properties   = data.properties
    local unicodes     = resources.unicodes -- name to unicode
    local indices      = resources.indices  -- index to unicodes
    local duplicates   = resources.duplicates

    -- begin of messy (not needed when cidmap)

    local mapdata        = raw.map or { }
    local unicodetoindex = mapdata and mapdata.map or { }
    local indextounicode = mapdata and mapdata.backmap or { }
 -- local encname        = lower(data.enc_name or raw.enc_name or mapdata.enc_name or "")
    local encname        = lower(data.enc_name or mapdata.enc_name or "")
    local criterium      = 0xFFFF -- for instance cambria has a lot of mess up there
    local privateoffset  = constructors.privateoffset

    -- end of messy

    if find(encname,"unicode") then -- unicodebmp, unicodefull, ...
        if trace_loading then
            report_otf("checking embedded unicode map %a",encname)
        end
        local reported = { }
        -- we loop over the original unicode->index mapping but we
        -- need to keep in mind that that one can have weird entries
        -- so we need some extra checking
        for maybeunicode, index in next, unicodetoindex do
            if descriptions[maybeunicode] then
                -- we ignore invalid unicodes (unicode = -1) (ff can map wrong to non private)
            else
                local unicode = indices[index]
                if not unicode then
                    -- weird (cjk or so?)
                elseif maybeunicode == unicode then
                    -- no need to add
                elseif unicode > privateoffset then
                    -- we have a non-unicode
                else
                    local d = descriptions[unicode]
                    if d then
                        local c = d.copies
                        if c then
                            c[maybeunicode] = true
                        else
                            d.copies = { [maybeunicode] = true }
                        end
                    elseif index and not reported[index] then
                        report_otf("missing index %i",index)
                        reported[index] = true
                    end
                end
            end
        end
        for unicode, data in next, descriptions do
            local d = data.copies
            if d then
                duplicates[unicode] = sortedkeys(d)
                data.copies = nil
            end
        end
    elseif properties.cidinfo then
        report_otf("warning: no unicode map, used cidmap %a",properties.cidinfo.usedname)
    else
        report_otf("warning: non unicode map %a, only using glyph unicode data",encname or "whatever")
    end

    if mapdata then
        mapdata.map     = { } -- clear some memory (virtual and created each time anyway)
        mapdata.backmap = { } -- clear some memory (virtual and created each time anyway)
    end
end

-- for the moment we assume that a font with lookups will not use
-- altuni so we stick to kerns only .. alternatively we can always
-- do an indirect lookup uni_to_uni . but then we need that in
-- all lookups

actions["add duplicates"] = function(data,filename,raw)
    local descriptions = data.descriptions
    local resources    = data.resources
    local properties   = data.properties
    local unicodes     = resources.unicodes -- name to unicode
    local indices      = resources.indices  -- index to unicodes
    local duplicates   = resources.duplicates
 -- for unicode, d in next, duplicates do
    for unicode, d in table.sortedhash(duplicates) do -- nicer for log
        local nofduplicates = #d
        if nofduplicates > 4 then
            if trace_loading then
                report_otf("ignoring excessive duplicates of %U (n=%s)",unicode,nofduplicates)
            end
        else
         -- local validduplicates = { }
            for i=1,nofduplicates do
                local u = d[i]
                if not descriptions[u] then
                    local description = descriptions[unicode]
                    local n = 0
                    for _, description in next, descriptions do
                        local kerns = description.kerns
                        if kerns then
                            for _, k in next, kerns do
                                local ku = k[unicode]
                                if ku then
                                    k[u] = ku
                                    n = n + 1
                                end
                            end
                        end
                        -- todo: lookups etc
                    end
                    if u > 0 then -- and
                        local duplicate = copy(description) -- else packing problem
                        duplicate.comment = formatters["copy of %U"](unicode)
                        descriptions[u] = duplicate
                     -- validduplicates[#validduplicates+1] = u
                        if trace_loading then
                            report_otf("duplicating %06U to %06U with index %H (%s kerns)",unicode,u,description.index,n)
                        end
                    end
                end
            end
         -- duplicates[unicode] = #validduplicates > 0 and validduplicates or nil
        end
    end
end

-- class      : nil base mark ligature component (maybe we don't need it in description)
-- boundingbox: split into ht/dp takes more memory (larger tables and less sharing)

actions["analyze glyphs"] = function(data,filename,raw) -- maybe integrate this in the previous
    local descriptions = data.descriptions
    local resources    = data.resources
    local metadata     = data.metadata
    local properties   = data.properties
    local hasitalics   = false
    local widths       = { }
    local marks        = { } -- always present (saves checking)
    for unicode, description in next, descriptions do
        local glyph  = description.glyph
        local italic = glyph.italic_correction -- only in a math font (we also have vert/horiz)
        if not italic then
            -- skip
        elseif italic == 0 then
            -- skip
        else
            description.italic = italic
            hasitalics = true
        end
        local width = glyph.width
        widths[width] = (widths[width] or 0) + 1
        local class = glyph.class
        if class then
            if class == "mark" then
                marks[unicode] = true
            end
            description.class = class
        end
    end
    -- flag italic
    properties.hasitalics = hasitalics
    -- flag marks
    resources.marks = marks
    -- share most common width for cjk fonts
    local wd, most = 0, 1
    for k,v in next, widths do
        if v > most then
            wd, most = k, v
        end
    end
    if most > 1000 then -- maybe 500
        if trace_loading then
            report_otf("most common width: %s (%s times), sharing (cjk font)",wd,most)
        end
        for unicode, description in next, descriptions do
            if description.width == wd then
             -- description.width = nil
            else
                description.width = description.glyph.width
            end
        end
        resources.defaultwidth = wd
    else
        for unicode, description in next, descriptions do
            description.width = description.glyph.width
        end
    end
end

actions["reorganize mark classes"] = function(data,filename,raw)
    local mark_classes = raw.mark_classes
    if mark_classes then
        local resources       = data.resources
        local unicodes        = resources.unicodes
        local markclasses     = { }
        resources.markclasses = markclasses -- reversed
        for name, class in next, mark_classes do
            local t = { }
            for s in gmatch(class,"[^ ]+") do
                t[unicodes[s]] = true
            end
            markclasses[name] = t
        end
    end
end

actions["reorganize features"] = function(data,filename,raw) -- combine with other
    local features = { }
    data.resources.features = features
    for k=1,#otf.glists do
        local what = otf.glists[k]
        local dw = raw[what]
        if dw then
            local f = { }
            features[what] = f
            for i=1,#dw do
                local d= dw[i]
                local dfeatures = d.features
                if dfeatures then
                    for i=1,#dfeatures do
                        local df = dfeatures[i]
                        local tag = strip(lower(df.tag))
                        local ft = f[tag]
                        if not ft then
                            ft = { }
                            f[tag] = ft
                        end
                        local dscripts = df.scripts
                        for i=1,#dscripts do
                            local d = dscripts[i]
                            local languages = d.langs
                            local script = strip(lower(d.script))
                            local fts = ft[script] if not fts then fts = {} ft[script] = fts end
                            for i=1,#languages do
                                fts[strip(lower(languages[i]))] = true
                            end
                        end
                    end
                end
            end
        end
    end
end

actions["reorganize anchor classes"] = function(data,filename,raw)
    local resources            = data.resources
    local anchor_to_lookup     = { }
    local lookup_to_anchor     = { }
    resources.anchor_to_lookup = anchor_to_lookup
    resources.lookup_to_anchor = lookup_to_anchor
    local classes              = raw.anchor_classes -- anchor classes not in final table
    if classes then
        for c=1,#classes do
            local class   = classes[c]
            local anchor  = class.name
            local lookups = class.lookup
            if type(lookups) ~= "table" then
                lookups = { lookups }
            end
            local a = anchor_to_lookup[anchor]
            if not a then
                a = { }
                anchor_to_lookup[anchor] = a
            end
            for l=1,#lookups do
                local lookup = lookups[l]
                local l = lookup_to_anchor[lookup]
                if l then
                    l[anchor] = true
                else
                    l = { [anchor] = true }
                    lookup_to_anchor[lookup] = l
                end
                a[lookup] = true
            end
        end
    end
end

-- local function checklookups(data,missing,nofmissing)
--     local resources    = data.resources
--     local unicodes     = resources.unicodes
--     local lookuptypes  = resources.lookuptypes
--     if not unicodes or not lookuptypes then
--         return
--     elseif nofmissing <= 0 then
--         return
--     end
--     local descriptions = data.descriptions
--     local private      = fonts.constructors and fonts.constructors.privateoffset or 0xF0000 -- 0x10FFFF
--     --
--     local ns, nl = 0, 0

--     local guess  = { }
--     -- helper
--     local function check(gname,code,unicode)
--         local description = descriptions[code]
--         -- no need to add a self reference
--         local variant = description.name
--         if variant == gname then
--             return
--         end
--         -- the variant already has a unicode (normally that results in a default tounicode to self)
--         local unic = unicodes[variant]
--         if unic == -1 or unic >= private or (unic >= 0xE000 and unic <= 0xF8FF) or unic == 0xFFFE or unic == 0xFFFF then
--             -- no default mapping and therefore maybe no tounicode yet
--         else
--             return
--         end
--         -- the variant already has a tounicode
--         if descriptions[code].unicode then
--             return
--         end
--         -- add to the list
--         local g = guess[variant]
--      -- local r = overloads[unicode]
--      -- if r then
--      --     unicode = r.unicode
--      -- end
--         if g then
--             g[gname] = unicode
--         else
--             guess[variant] = { [gname] = unicode }
--         end
--     end
--     --
--     for unicode, description in next, descriptions do
--         local slookups = description.slookups
--         if slookups then
--             local gname = description.name
--             for tag, data in next, slookups do
--                 local lookuptype = lookuptypes[tag]
--                 if lookuptype == "alternate" then
--                     for i=1,#data do
--                         check(gname,data[i],unicode)
--                     end
--                 elseif lookuptype == "substitution" then
--                     check(gname,data,unicode)
--                 end
--             end
--         end
--         local mlookups = description.mlookups
--         if mlookups then
--             local gname = description.name
--             for tag, list in next, mlookups do
--                 local lookuptype = lookuptypes[tag]
--                 if lookuptype == "alternate" then
--                     for i=1,#list do
--                         local data = list[i]
--                         for i=1,#data do
--                             check(gname,data[i],unicode)
--                         end
--                     end
--                 elseif lookuptype == "substitution" then
--                     for i=1,#list do
--                         check(gname,list[i],unicode)
--                     end
--                 end
--             end
--         end
--     end
--     -- resolve references
--     local done = true
--     while done do
--         done = false
--         for k, v in next, guess do
--             if type(v) ~= "number" then
--                 for kk, vv in next, v do
--                     if vv == -1 or vv >= private or (vv >= 0xE000 and vv <= 0xF8FF) or vv == 0xFFFE or vv == 0xFFFF then
--                         local uu = guess[kk]
--                         if type(uu) == "number" then
--                             guess[k] = uu
--                             done = true
--                         end
--                     else
--                         guess[k] = vv
--                         done = true
--                     end
--                 end
--             end
--         end
--     end
--     -- wrap up
--     local orphans = 0
--     local guessed = 0
--     for k, v in next, guess do
--         if type(v) == "number" then
--             descriptions[unicodes[k]].unicode = descriptions[v].unicode or v -- can also be a table
--             guessed = guessed + 1
--         else
--             local t = nil
--             local l = lower(k)
--             local u = unicodes[l]
--             if not u then
--                 orphans = orphans + 1
--             elseif u == -1 or u >= private or (u >= 0xE000 and u <= 0xF8FF) or u == 0xFFFE or u == 0xFFFF then
--                 local unicode = descriptions[u].unicode
--                 if unicode then
--                     descriptions[unicodes[k]].unicode = unicode
--                     guessed = guessed + 1
--                 else
--                     orphans = orphans + 1
--                 end
--             else
--                 orphans = orphans + 1
--             end
--         end
--     end
--     if trace_loading and orphans > 0 or guessed > 0 then
--         report_otf("%s glyphs with no related unicode, %s guessed, %s orphans",guessed+orphans,guessed,orphans)
--     end
-- end

actions["prepare tounicode"] = function(data,filename,raw)
    fonts.mappings.addtounicode(data,filename)
end

local g_directions = {
    gsub_contextchain        =  1,
    gpos_contextchain        =  1,
 -- gsub_context             =  1,
 -- gpos_context             =  1,
    gsub_reversecontextchain = -1,
    gpos_reversecontextchain = -1,
}
-- The following is no longer needed as AAT is ignored per end October 2013.
--
-- -- Research by Khaled Hosny has demonstrated that the font loader merges
-- -- regular and AAT features and that these can interfere (especially because
-- -- we dropped checking for valid features elsewhere. So, we just check for
-- -- the special flag and drop the feature if such a tag is found.
--
-- local function supported(features)
--     for i=1,#features do
--         if features[i].ismac then
--             return false
--         end
--     end
--     return true
-- end

actions["reorganize subtables"] = function(data,filename,raw)
    local resources       = data.resources
    local sequences       = { }
    local lookups         = { }
    local chainedfeatures = { }
    resources.sequences   = sequences
    resources.lookups     = lookups -- we also have lookups in data itself
    for k=1,#otf.glists do
        local what = otf.glists[k]
        local dw = raw[what]
        if dw then
            for k=1,#dw do
                local gk = dw[k]
                local features = gk.features
             -- if not features or supported(features) then -- not always features !
                    local typ = gk.type
                    local chain = g_directions[typ] or 0
                    local subtables = gk.subtables
                    if subtables then
                        local t = { }
                        for s=1,#subtables do
                            t[s] = subtables[s].name
                        end
                        subtables = t
                    end
                    local flags, markclass = gk.flags, nil
                    if flags then
                        local t = { -- forcing false packs nicer
                            (flags.ignorecombiningmarks and "mark")     or false,
                            (flags.ignoreligatures      and "ligature") or false,
                            (flags.ignorebaseglyphs     and "base")     or false,
                             flags.r2l                                  or false,
                        }
                        markclass = flags.mark_class
                        if markclass then
                            markclass = resources.markclasses[markclass]
                        end
                        flags = t
                    end
                    --
                    local name = gk.name
                    --
                    if not name then
                        -- in fact an error
                        report_otf("skipping weird lookup number %s",k)
                    elseif features then
                        -- scripts, tag, ismac
                        local f = { }
                        local o = { }
                        for i=1,#features do
                            local df = features[i]
                            local tag = strip(lower(df.tag))
                            local ft = f[tag]
                            if not ft then
                                ft = { }
                                f[tag] = ft
                                o[#o+1] = tag
                            end
                            local dscripts = df.scripts
                            for i=1,#dscripts do
                                local d = dscripts[i]
                                local languages = d.langs
                                local script = strip(lower(d.script))
                                local fts = ft[script] if not fts then fts = {} ft[script] = fts end
                                for i=1,#languages do
                                    fts[strip(lower(languages[i]))] = true
                                end
                            end
                        end
                        sequences[#sequences+1] = {
                            type      = typ,
                            chain     = chain,
                            flags     = flags,
                            name      = name,
                            subtables = subtables,
                            markclass = markclass,
                            features  = f,
                            order     = o,
                        }
                    else
                        lookups[name] = {
                            type      = typ,
                            chain     = chain,
                            flags     = flags,
                            subtables = subtables,
                            markclass = markclass,
                        }
                    end
             -- end
            end
        end
    end
end

actions["prepare lookups"] = function(data,filename,raw)
    local lookups = raw.lookups
    if lookups then
        data.lookups = lookups
    end
end

-- The reverse handler does a bit redundant splitting but it's seldom
-- seen so we don't bother too much. We could store the replacement
-- in the current list (value instead of true) but it makes other code
-- uglier. Maybe some day.

local function t_uncover(splitter,cache,covers)
    local result = { }
    for n=1,#covers do
        local cover = covers[n]
        local uncovered = cache[cover]
        if not uncovered then
            uncovered = lpegmatch(splitter,cover)
            cache[cover] = uncovered
        end
        result[n] = uncovered
    end
    return result
end

local function s_uncover(splitter,cache,cover)
    if cover == "" then
        return nil
    else
        local uncovered = cache[cover]
        if not uncovered then
            uncovered = lpegmatch(splitter,cover)
         -- for i=1,#uncovered do
         --     uncovered[i] = { [uncovered[i]] = true }
         -- end
            cache[cover] = uncovered
        end
        return { uncovered }
    end
end

local function t_hashed(t,cache)
    if t then
        local ht = { }
        for i=1,#t do
            local ti = t[i]
            local tih = cache[ti]
            if not tih then
                local tn = #ti
                if tn == 1 then
                    tih = { [ti[1]] = true }
                else
                    tih = { }
                    for i=1,tn do
                        tih[ti[i]] = true
                    end
                end
                cache[ti] = tih
            end
            ht[i] = tih
        end
        return ht
    else
        return nil
    end
end

-- local s_hashed = t_hashed

local function s_hashed(t,cache)
    if t then
        local tf = t[1]
        local nf = #tf
        if nf == 1 then
            return { [tf[1]] = true }
        else
            local ht = { }
            for i=1,nf do
                ht[i] = { [tf[i]] = true }
            end
            return ht
        end
    else
        return nil
    end
end

local function r_uncover(splitter,cache,cover,replacements)
    if cover == "" then
        return nil
    else
        -- we always have current as { } even in the case of one
        local uncovered = cover[1]
        local replaced = cache[replacements]
        if not replaced then
            replaced = lpegmatch(splitter,replacements)
            cache[replacements] = replaced
        end
        local nu, nr = #uncovered, #replaced
        local r = { }
        if nu == nr then
            for i=1,nu do
                r[uncovered[i]] = replaced[i]
            end
        end
        return r
    end
end

actions["reorganize lookups"] = function(data,filename,raw) -- we could check for "" and n == 0
    -- we prefer the before lookups in a normal order
    if data.lookups then
        local helpers      = data.helpers
        local duplicates   = data.resources.duplicates
        local splitter     = helpers.tounicodetable
        local t_u_cache    = { }
        local s_u_cache    = t_u_cache -- string keys
        local t_h_cache    = { }
        local s_h_cache    = t_h_cache -- table keys (so we could use one cache)
        local r_u_cache    = { } -- maybe shared
        helpers.matchcache = t_h_cache -- so that we can add duplicates
        --
        for _, lookup in next, data.lookups do
            local rules = lookup.rules
            if rules then
                local format = lookup.format
                if format == "class" then
                    local before_class = lookup.before_class
                    if before_class then
                        before_class = t_uncover(splitter,t_u_cache,reversed(before_class))
                    end
                    local current_class = lookup.current_class
                    if current_class then
                        current_class = t_uncover(splitter,t_u_cache,current_class)
                    end
                    local after_class = lookup.after_class
                    if after_class then
                        after_class = t_uncover(splitter,t_u_cache,after_class)
                    end
                    for i=1,#rules do
                        local rule = rules[i]
                        local class = rule.class
                        local before = class.before
                        if before then
                            for i=1,#before do
                                before[i] = before_class[before[i]] or { }
                            end
                            rule.before = t_hashed(before,t_h_cache)
                        end
                        local current = class.current
                        local lookups = rule.lookups
                        if current then
                            for i=1,#current do
                                current[i] = current_class[current[i]] or { }
                                -- let's not be sparse
                                if lookups and not lookups[i] then
                                    lookups[i] = "" -- (was: false) e.g. we can have two lookups and one replacement
                                end
                                -- end of fix
                            end
                            rule.current = t_hashed(current,t_h_cache)
                        end
                        local after = class.after
                        if after then
                            for i=1,#after do
                                after[i] = after_class[after[i]] or { }
                            end
                            rule.after = t_hashed(after,t_h_cache)
                        end
                        rule.class = nil
                    end
                    lookup.before_class  = nil
                    lookup.current_class = nil
                    lookup.after_class   = nil
                    lookup.format        = "coverage"
                elseif format == "coverage" then
                    for i=1,#rules do
                        local rule = rules[i]
                        local coverage = rule.coverage
                        if coverage then
                            local before = coverage.before
                            if before then
                                before = t_uncover(splitter,t_u_cache,reversed(before))
                                rule.before = t_hashed(before,t_h_cache)
                            end
                            local current = coverage.current
                            if current then
                                current = t_uncover(splitter,t_u_cache,current)
                                -- let's not be sparse
                                local lookups = rule.lookups
                                if lookups then
                                    for i=1,#current do
                                        if not lookups[i] then
                                            lookups[i] = "" -- fix sparse array
                                        end
                                    end
                                end
                                --
                                rule.current = t_hashed(current,t_h_cache)
                            end
                            local after = coverage.after
                            if after then
                                after = t_uncover(splitter,t_u_cache,after)
                                rule.after = t_hashed(after,t_h_cache)
                            end
                            rule.coverage = nil
                        end
                    end
                elseif format == "reversecoverage" then -- special case, single substitution only
                    for i=1,#rules do
                        local rule = rules[i]
                        local reversecoverage = rule.reversecoverage
                        if reversecoverage then
                            local before = reversecoverage.before
                            if before then
                                before = t_uncover(splitter,t_u_cache,reversed(before))
                                rule.before = t_hashed(before,t_h_cache)
                            end
                            local current = reversecoverage.current
                            if current then
                                current = t_uncover(splitter,t_u_cache,current)
                                rule.current = t_hashed(current,t_h_cache)
                            end
                            local after = reversecoverage.after
                            if after then
                                after = t_uncover(splitter,t_u_cache,after)
                                rule.after = t_hashed(after,t_h_cache)
                            end
                            local replacements = reversecoverage.replacements
                            if replacements then
                                rule.replacements = r_uncover(splitter,r_u_cache,current,replacements)
                            end
                            rule.reversecoverage = nil
                        end
                    end
                elseif format == "glyphs" then
                    -- I could store these more efficient (as not we use a nested tables for before,
                    -- after and current but this features happens so seldom that I don't bother
                    -- about it right now.
                    for i=1,#rules do
                        local rule = rules[i]
                        local glyphs = rule.glyphs
                        if glyphs then
                            local fore = glyphs.fore
                            if fore and fore ~= "" then
                                fore = s_uncover(splitter,s_u_cache,fore)
                                rule.after = s_hashed(fore,s_h_cache)
                            end
                            local back = glyphs.back
                            if back then
                                back = s_uncover(splitter,s_u_cache,back)
                                rule.before = s_hashed(back,s_h_cache)
                            end
                            local names = glyphs.names
                            if names then
                                names = s_uncover(splitter,s_u_cache,names)
                                rule.current = s_hashed(names,s_h_cache)
                            end
                            rule.glyphs = nil
                            local lookups = rule.lookups
                            if lookups then
                                for i=1,#names do
                                    if not lookups[i] then
                                        lookups[i] = "" -- fix sparse array
                                    end
                                end
                            end
                        end
                    end
                end
            end
        end
    end
end

actions["expand lookups"] = function(data,filename,raw) -- we could check for "" and n == 0
    if data.lookups then
        local cache = data.helpers.matchcache
        if cache then
            local duplicates = data.resources.duplicates
            for key, hash in next, cache do
                local done = nil
                for key in next, hash do
                    local unicode = duplicates[key]
                    if not unicode then
                        -- no duplicate
                    elseif type(unicode) == "table" then
                        -- multiple duplicates
                        for i=1,#unicode do
                            local u = unicode[i]
                            if hash[u] then
                                -- already in set
                            elseif done then
                                done[u] = key
                            else
                                done = { [u] = key }
                            end
                        end
                    else
                        -- one duplicate
                        if hash[unicode] then
                            -- already in set
                        elseif done then
                            done[unicode] = key
                        else
                            done = { [unicode] = key }
                        end
                    end
                end
                if done then
                    for u in next, done do
                        hash[u] = true
                    end
                end
            end
        end
    end
end

local function check_variants(unicode,the_variants,splitter,unicodes)
    local variants = the_variants.variants
    if variants then -- use splitter
        local glyphs = lpegmatch(splitter,variants)
        local done   = { [unicode] = true }
        local n      = 0
        for i=1,#glyphs do
            local g = glyphs[i]
            if done[g] then
                if i > 1 then
                    report_otf("skipping cyclic reference %U in math variant %U",g,unicode)
                end
            else
                if n == 0 then
                    n = 1
                    variants = { g }
                else
                    n = n + 1
                    variants[n] = g
                end
                done[g] = true
            end
        end
        if n == 0 then
            variants = nil
        end
    end
    local parts = the_variants.parts
    if parts then
        local p = #parts
        if p > 0 then
            for i=1,p do
                local pi = parts[i]
                pi.glyph = unicodes[pi.component] or 0
                pi.component = nil
            end
        else
            parts = nil
        end
    end
    local italic = the_variants.italic
    if italic and italic == 0 then
        italic = nil
    end
    return variants, parts, italic
end

actions["analyze math"] = function(data,filename,raw)
    if raw.math then
        data.metadata.math = raw.math
        local unicodes = data.resources.unicodes
        local splitter = data.helpers.tounicodetable
        for unicode, description in next, data.descriptions do
            local glyph        = description.glyph
            local mathkerns    = glyph.mathkern -- singular
            local hvariants    = glyph.horiz_variants
            local vvariants    = glyph.vert_variants
            local accent       = glyph.top_accent
            local italic       = glyph.italic_correction
            if mathkerns or hvariants or vvariants or accent or italic then
                local math = { }
                if accent then
                    math.accent = accent
                end
                if mathkerns then
                    for k, v in next, mathkerns do
                        if not next(v) then
                            mathkerns[k] = nil
                        else
                            for k, v in next, v do
                                if v == 0 then
                                    k[v] = nil -- height / kern can be zero
                                end
                            end
                        end
                    end
                    math.kerns = mathkerns
                end
                if hvariants then
                    math.hvariants, math.hparts, math.hitalic = check_variants(unicode,hvariants,splitter,unicodes)
                end
                if vvariants then
                    math.vvariants, math.vparts, math.vitalic = check_variants(unicode,vvariants,splitter,unicodes)
                end
                if italic and italic ~= 0 then
                    math.italic = italic
                end
                description.math = math
            end
        end
    end
end

actions["reorganize glyph kerns"] = function(data,filename,raw)
    local descriptions = data.descriptions
    local resources    = data.resources
    local unicodes     = resources.unicodes
    for unicode, description in next, descriptions do
        local kerns = description.glyph.kerns
        if kerns then
            local newkerns = { }
            for k, kern in next, kerns do
                local name   = kern.char
                local offset = kern.off
                local lookup = kern.lookup
                if name and offset and lookup then
                    local unicode = unicodes[name]
                    if unicode then
                        if type(lookup) == "table" then
                            for l=1,#lookup do
                                local lookup = lookup[l]
                                local lookupkerns = newkerns[lookup]
                                if lookupkerns then
                                    lookupkerns[unicode] = offset
                                else
                                    newkerns[lookup] = { [unicode] = offset }
                                end
                            end
                        else
                            local lookupkerns = newkerns[lookup]
                            if lookupkerns then
                                lookupkerns[unicode] = offset
                            else
                                newkerns[lookup] = { [unicode] = offset }
                            end
                        end
                    elseif trace_loading then
                        report_otf("problems with unicode %a of kern %a of glyph %U",name,k,unicode)
                    end
                end
            end
            description.kerns = newkerns
        end
    end
end

actions["merge kern classes"] = function(data,filename,raw)
    local gposlist = raw.gpos
    if gposlist then
        local descriptions = data.descriptions
        local resources    = data.resources
        local unicodes     = resources.unicodes
        local splitter     = data.helpers.tounicodetable
        local ignored      = 0
        local blocked      = 0
        for gp=1,#gposlist do
            local gpos = gposlist[gp]
            local subtables = gpos.subtables
            if subtables then
                local first_done = { } -- could become an option so that we can deal with buggy fonts that don't get fixed
                local split = { } -- saves time .. although probably not that much any more in the fixed luatex kernclass table
                for s=1,#subtables do
                    local subtable = subtables[s]
                    local kernclass = subtable.kernclass -- name is inconsistent with anchor_classes
                    local lookup = subtable.lookup or subtable.name
                    if kernclass then -- the next one is quite slow
                        -- as fas as i can see the kernclass is a table with one entry and offsets
                        -- have no [1] so we could remov eon elevel (kernclass) and start offsets
                        -- at 1 but we're too far down the road now to fix that
                        if #kernclass > 0 then
                            kernclass = kernclass[1]
                            lookup    = type(kernclass.lookup) == "string" and kernclass.lookup or lookup
                            report_otf("fixing kernclass table of lookup %a",lookup)
                        end
                        local firsts  = kernclass.firsts
                        local seconds = kernclass.seconds
                        local offsets = kernclass.offsets
                     -- if offsets[1] == nil then
                     --     offsets[1] = "" -- defaults ?
                     -- end
                        for n, s in next, firsts do
                            split[s] = split[s] or lpegmatch(splitter,s)
                        end
                        local maxseconds = 0
                        for n, s in next, seconds do
                            if n > maxseconds then
                                maxseconds = n
                            end
                            split[s] = split[s] or lpegmatch(splitter,s)
                        end
                        for fk=1,#firsts do -- maxfirsts ?
                            local fv = firsts[fk]
                            local splt = split[fv]
                            if splt then
                                local extrakerns = { }
                                local baseoffset = (fk-1) * maxseconds
                             -- for sk, sv in next, seconds do
                                for sk=2,maxseconds do
                                    local sv = seconds[sk]
                                    if sv then
                                        local splt = split[sv]
                                        if splt then -- redundant test
                                            local offset = offsets[baseoffset + sk]
                                            if offset then
                                                for i=1,#splt do
                                                    extrakerns[splt[i]] = offset
                                                end
                                            end
                                        end
                                    end
                                end
                                for i=1,#splt do
                                    local first_unicode = splt[i]
                                    if first_done[first_unicode] then
                                        report_otf("lookup %a: ignoring further kerns of %C",lookup,first_unicode)
                                        blocked = blocked + 1
                                    else
                                        first_done[first_unicode] = true
                                        local description = descriptions[first_unicode]
                                        if description then
                                            local kerns = description.kerns
                                            if not kerns then
                                                kerns = { } -- unicode indexed !
                                                description.kerns = kerns
                                            end
                                            local lookupkerns = kerns[lookup]
                                            if not lookupkerns then
                                                lookupkerns = { }
                                                kerns[lookup] = lookupkerns
                                            end
                                            if overloadkerns then
                                                for second_unicode, kern in next, extrakerns do
                                                    lookupkerns[second_unicode] = kern
                                                end
                                            else
                                                for second_unicode, kern in next, extrakerns do
                                                    local k = lookupkerns[second_unicode]
                                                    if not k then
                                                        lookupkerns[second_unicode] = kern
                                                    elseif k ~= kern then
                                                        if trace_loading then
                                                            report_otf("lookup %a: ignoring overload of kern between %C and %C, rejecting %a, keeping %a",lookup,first_unicode,second_unicode,k,kern)
                                                        end
                                                        ignored = ignored + 1
                                                    end
                                                end
                                            end
                                        elseif trace_loading then
                                            report_otf("no glyph data for %U", first_unicode)
                                        end
                                    end
                                end
                            end
                        end
                        subtable.kernclass = { }
                    end
                end
            end
        end
        if ignored > 0 then
            report_otf("%s kern overloads ignored",ignored)
        end
        if blocked > 0 then
            report_otf("%s successive kerns blocked",blocked)
        end
    end
end

actions["check glyphs"] = function(data,filename,raw)
    for unicode, description in next, data.descriptions do
        description.glyph = nil
    end
end

-- future versions will remove _

local valid = (R("\x00\x7E") - S("(){}[]<>%/ \n\r\f\v"))^0 * P(-1)

local function valid_ps_name(str)
    return str and str ~= "" and #str < 64 and lpegmatch(valid,str) and true or false
end

actions["check metadata"] = function(data,filename,raw)
    local metadata = data.metadata
    for _, k in next, mainfields do
        if valid_fields[k] then
            local v = raw[k]
            if not metadata[k] then
                metadata[k] = v
            end
        end
    end
 -- metadata.pfminfo = raw.pfminfo -- not already done?
    local ttftables = metadata.ttf_tables
    if ttftables then
        for i=1,#ttftables do
            ttftables[i].data = "deleted"
        end
    end
    --
    local state = metadata.validation_state
    local names = raw.names
    --
    if state and table.contains(state,"bad_ps_fontname") then
        -- the ff library does a bit too much (and wrong) checking ... so we need to catch this
        -- at least for now
        local function valid(what)
            if names then
                for i=1,#names do
                    local list = names[i]
                    local names = list.names
                    if names then
                        local name = names[what]
                        if name and valid_ps_name(name) then
                            return name
                        end
                    end
                end
            end
        end
        local function check(what)
            local oldname = metadata[what]
            if valid_ps_name(oldname) then
                report_otf("ignoring warning %a because %s %a is proper ASCII","bad_ps_fontname",what,oldname)
            else
                local newname = valid(what)
                if not newname then
                    newname = formatters["bad-%s-%s"](what,file.nameonly(filename))
                end
                local warning = formatters["overloading %s from invalid ASCII name %a to %a"](what,oldname,newname)
                data.warnings[#data.warnings+1] = warning
                report_otf(warning)
                metadata[what] = newname
            end
        end
        check("fontname")
        check("fullname")
    end
    --
    if names then
        local psname = metadata.psname
        if not psname or psname == "" then
            for i=1,#names do
                local name = names[i]
                -- Currently we use the same restricted search as in the new context (specific) font loader
                -- but we might add more lang checks (it worked ok in the new loaded so now we're in sync)
                -- This check here is also because there are (esp) cjk fonts out there with psnames different
                -- from fontnames (gives a bad lookup in backend).
                if lower(name.lang) == "english (us)" then
                    local specification = name.names
                    if specification then
                        local postscriptname = specification.postscriptname
                        if postscriptname then
                            psname = postscriptname
                        end
                    end
                end
                break
            end
        end
        if psname ~= metadata.fontname then
            report_otf("fontname %a, fullname %a, psname %a",metadata.fontname,metadata.fullname,psname)
        end
        metadata.psname = psname
    end
    --
    if state and table.contains(state,"bad_cmap_table") then
        report_otf("fontfile %a has bad cmap tables",filename)
    end
end

actions["cleanup tables"] = function(data,filename,raw)
    local duplicates = data.resources.duplicates
    if duplicates then
        for k, v in next, duplicates do
            if #v == 1 then
                duplicates[k] = v[1]
            end
        end
    end
    data.resources.indices  = nil -- not needed
    data.resources.unicodes = nil -- delayed
    data.helpers            = nil -- tricky as we have no unicodes any more
end

-- kern: ttf has a table with kerns
--
-- Weird, as maxfirst and maxseconds can have holes, first seems to be indexed, but
-- seconds can start at 2 .. this need to be fixed as getn as well as # are sort of
-- unpredictable alternatively we could force an [1] if not set (maybe I will do that
-- anyway).

-- we can share { } as it is never set

-- ligatures have an extra specification.char entry that we don't use

-- mlookups only with pairs and ligatures

actions["reorganize glyph lookups"] = function(data,filename,raw)
    local resources    = data.resources
    local unicodes     = resources.unicodes
    local descriptions = data.descriptions
    local splitter     = data.helpers.tounicodelist

    local lookuptypes  = resources.lookuptypes

    for unicode, description in next, descriptions do
        local lookups = description.glyph.lookups
        if lookups then
            for tag, lookuplist in next, lookups do
                for l=1,#lookuplist do
                    local lookup        = lookuplist[l]
                    local specification = lookup.specification
                    local lookuptype    = lookup.type
                    local lt = lookuptypes[tag]
                    if not lt then
                        lookuptypes[tag] = lookuptype
                    elseif lt ~= lookuptype then
                        report_otf("conflicting lookuptypes, %a points to %a and %a",tag,lt,lookuptype)
                    end
                    if lookuptype == "ligature" then
                        lookuplist[l] = { lpegmatch(splitter,specification.components) }
                    elseif lookuptype == "alternate" then
                        lookuplist[l] = { lpegmatch(splitter,specification.components) }
                    elseif lookuptype == "substitution" then
                        lookuplist[l] = unicodes[specification.variant]
                    elseif lookuptype == "multiple" then
                        lookuplist[l] = { lpegmatch(splitter,specification.components) }
                    elseif lookuptype == "position" then
                        lookuplist[l] = {
                            specification.x or 0,
                            specification.y or 0,
                            specification.h or 0,
                            specification.v or 0
                        }
                    elseif lookuptype == "pair" then
                        local one    = specification.offsets[1]
                        local two    = specification.offsets[2]
                        local paired = unicodes[specification.paired]
                        if one then
                            if two then
                                lookuplist[l] = { paired, { one.x or 0, one.y or 0, one.h or 0, one.v or 0 }, { two.x or 0, two.y or 0, two.h or 0, two.v or 0 } }
                            else
                                lookuplist[l] = { paired, { one.x or 0, one.y or 0, one.h or 0, one.v or 0 } }
                            end
                        else
                            if two then
                                lookuplist[l] = { paired, { }, { two.x or 0, two.y or 0, two.h or 0, two.v or 0} } -- maybe nil instead of { }
                            else
                                lookuplist[l] = { paired }
                            end
                        end
                    end
                end
            end
            local slookups, mlookups
            for tag, lookuplist in next, lookups do
                if #lookuplist == 1 then
                    if slookups then
                        slookups[tag] = lookuplist[1]
                    else
                        slookups = { [tag] = lookuplist[1] }
                    end
                else
                    if mlookups then
                        mlookups[tag] = lookuplist
                    else
                        mlookups = { [tag] = lookuplist }
                    end
                end
            end
            if slookups then
                description.slookups = slookups
            end
            if mlookups then
                description.mlookups = mlookups
            end
         -- description.lookups = nil
        end
    end
end

local zero = { 0, 0 }

actions["reorganize glyph anchors"] = function(data,filename,raw)
    local descriptions = data.descriptions
    for unicode, description in next, descriptions do
        local anchors = description.glyph.anchors
        if anchors then
            for class, data in next, anchors do
                if class == "baselig" then
                    for tag, specification in next, data do
                     -- for i=1,#specification do
                     --     local si = specification[i]
                     --     specification[i] = { si.x or 0, si.y or 0 }
                     -- end
                        -- can be sparse so we need to fill the holes
                        local n = 0
                        for k, v in next, specification do
                            if k > n then
                                n = k
                            end
                            local x, y = v.x, v.y
                            if x or y then
                                specification[k] = { x or 0, y or 0 }
                            else
                                specification[k] = zero
                            end
                        end
                        local t = { }
                        for i=1,n do
                            t[i] = specification[i] or zero
                        end
                        data[tag] = t -- so # is okay (nicer for packer)
                    end
                else
                    for tag, specification in next, data do
                        local x, y = specification.x, specification.y
                        if x or y then
                            data[tag] = { x or 0, y or 0 }
                        else
                            data[tag] = zero
                        end
                    end
                end
            end
            description.anchors = anchors
        end
    end
end

local bogusname   = (P("uni") + P("u")) * R("AF","09")^4
                  + (P("index") + P("glyph") + S("Ii") * P("dentity") * P(".")^0) * R("09")^1
local uselessname = (1-bogusname)^0 * bogusname

actions["purge names"] = function(data,filename,raw) -- not used yet
    if purge_names then
        local n = 0
        for u, d in next, data.descriptions do
            if lpegmatch(uselessname,d.name) then
                n = n + 1
                d.name = nil
            end
         -- d.comment = nil
        end
        if n > 0 then
            report_otf("%s bogus names removed",n)
        end
    end
end

actions["compact lookups"] = function(data,filename,raw)
    if not compact_lookups then
        report_otf("not compacting")
        return
    end
    -- create keyhash
    local last  = 0
    local tags  = table.setmetatableindex({ },
        function(t,k)
            last = last + 1
            t[k] = last
            return last
        end
    )
    --
    local descriptions = data.descriptions
    local resources    = data.resources
    --
    for u, d in next, descriptions do
        --
        -- -- we can also compact anchors and cursives (basechar basemark baselig mark)
        --
        local slookups = d.slookups
        if type(slookups) == "table" then
            local s = { }
            for k, v in next, slookups do
                s[tags[k]] = v
            end
            d.slookups = s
        end
        --
        local mlookups = d.mlookups
        if type(mlookups) == "table" then
            local m = { }
            for k, v in next, mlookups do
                m[tags[k]] = v
            end
            d.mlookups = m
        end
        --
        local kerns = d.kerns
        if type(kerns) == "table" then
            local t = { }
            for k, v in next, kerns do
                t[tags[k]] = v
            end
            d.kerns = t
        end
    end
    --
    local lookups = data.lookups
    if lookups then
        local l = { }
        for k, v in next, lookups do
            local rules = v.rules
            if rules then
                for i=1,#rules do
                    local l = rules[i].lookups
                    if type(l) == "table" then
                        for i=1,#l do
                            l[i] = tags[l[i]]
                        end
                    end
                end
            end
            l[tags[k]] = v
        end
        data.lookups = l
    end
    --
    local lookups = resources.lookups
    if lookups then
        local l = { }
        for k, v in next, lookups do
            local s = v.subtables
            if type(s) == "table" then
                for i=1,#s do
                    s[i] = tags[s[i]]
                end
            end
            l[tags[k]] = v
        end
        resources.lookups = l
    end
    --
    local sequences = resources.sequences
    if sequences then
        for i=1,#sequences do
            local s = sequences[i]
            local n = s.name
            if n then
                s.name = tags[n]
            end
            local t = s.subtables
            if type(t) == "table" then
                for i=1,#t do
                    t[i] = tags[t[i]]
                end
            end
        end
    end
    --
    local lookuptypes = resources.lookuptypes
    if lookuptypes then
        local l = { }
        for k, v in next, lookuptypes do
            l[tags[k]] = v
        end
        resources.lookuptypes = l
    end
    --
    local anchor_to_lookup = resources.anchor_to_lookup
    if anchor_to_lookup then
        for anchor, lookups in next, anchor_to_lookup do
            local l = { }
            for lookup, value in next, lookups do
                l[tags[lookup]] = value
            end
            anchor_to_lookup[anchor] = l
        end
    end
    --
    local lookup_to_anchor = resources.lookup_to_anchor
    if lookup_to_anchor then
        local l = { }
        for lookup, value in next, lookup_to_anchor do
            l[tags[lookup]] = value
        end
        resources.lookup_to_anchor = l
    end
    --
    tags = table.swapped(tags)
    --
    report_otf("%s lookup tags compacted",#tags)
    --
    resources.lookuptags = tags
end

-- modes: node, base, none

function otf.setfeatures(tfmdata,features)
    local okay = constructors.initializefeatures("otf",tfmdata,features,trace_features,report_otf)
    if okay then
        return constructors.collectprocessors("otf",tfmdata,features,trace_features,report_otf)
    else
        return { } -- will become false
    end
end

-- the first version made a top/mid/not extensible table, now we just
-- pass on the variants data and deal with it in the tfm scaler (there
-- is no longer an extensible table anyway)
--
-- we cannot share descriptions as virtual fonts might extend them (ok,
-- we could use a cache with a hash
--
-- we already assign an empty tabel to characters as we can add for
-- instance protruding info and loop over characters; one is not supposed
-- to change descriptions and if one does so one should make a copy!

local function copytotfm(data,cache_id)
    if data then
        local metadata       = data.metadata
        local warnings       = data.warnings
        local resources      = data.resources
        local properties     = derivetable(data.properties)
        local descriptions   = derivetable(data.descriptions)
        local goodies        = derivetable(data.goodies)
        local characters     = { }
        local parameters     = { }
        local mathparameters = { }
        --
        local pfminfo        = metadata.pfminfo  or { }
        local resources      = data.resources
        local unicodes       = resources.unicodes
     -- local mode           = data.mode or "base"
        local spaceunits     = 500
        local spacer         = "space"
        local designsize     = metadata.designsize or metadata.design_size or 100
        local minsize        = metadata.minsize or metadata.design_range_bottom or designsize
        local maxsize        = metadata.maxsize or metadata.design_range_top    or designsize
        local mathspecs      = metadata.math
        --
        if designsize == 0 then
            designsize = 100
            minsize    = 100
            maxsize    = 100
        end
        if mathspecs then
            for name, value in next, mathspecs do
                mathparameters[name] = value
            end
        end
        for unicode, _ in next, data.descriptions do -- use parent table
            characters[unicode] = { }
        end
        if mathspecs then
            -- we could move this to the scaler but not that much is saved
            -- and this is cleaner
            for unicode, character in next, characters do
                local d = descriptions[unicode]
                local m = d.math
                if m then
                    -- watch out: luatex uses horiz_variants for the parts
                    --
                    local italic   = m.italic
                    local vitalic  = m.vitalic
                    --
                    local variants = m.hvariants
                    local parts    = m.hparts
                 -- local done     = { [unicode] = true }
                    if variants then
                        local c = character
                        for i=1,#variants do
                            local un = variants[i]
                         -- if done[un] then
                         --  -- report_otf("skipping cyclic reference %U in math variant %U",un,unicode)
                         -- else
                                c.next = un
                                c = characters[un]
                         --     done[un] = true
                         -- end
                        end -- c is now last in chain
                        c.horiz_variants = parts
                    elseif parts then
                        character.horiz_variants = parts
                        italic = m.hitalic
                    end
                    --
                    local variants = m.vvariants
                    local parts    = m.vparts
                 -- local done     = { [unicode] = true }
                    if variants then
                        local c = character
                        for i=1,#variants do
                            local un = variants[i]
                         -- if done[un] then
                         --  -- report_otf("skipping cyclic reference %U in math variant %U",un,unicode)
                         -- else
                                c.next = un
                                c = characters[un]
                         --     done[un] = true
                         -- end
                        end -- c is now last in chain
                        c.vert_variants = parts
                    elseif parts then
                        character.vert_variants = parts
                    end
                    --
                    if italic and italic ~= 0 then
                        character.italic = italic -- overload
                    end
                    if vitalic and vitalic ~= 0 then
                        character.vert_italic = vitalic
                    end
                    --
                    local accent = m.accent
                    if accent then
                        character.accent = accent
                    end
                    --
                    local kerns = m.kerns
                    if kerns then
                        character.mathkerns = kerns
                    end
                end
            end
        end
        -- end math
        -- we need a runtime lookup because of running from cdrom or zip, brrr (shouldn't we use the basename then?)
        local filename = constructors.checkedfilename(resources)
        local fontname = metadata.fontname
        local fullname = metadata.fullname or fontname
        local psname   = metadata.psname or fontname or fullname
        local units    = metadata.units or metadata.units_per_em or 1000
        --
        if units == 0 then -- catch bugs in fonts
            units = 1000 -- maybe 2000 when ttf
            metadata.units = 1000
            report_otf("changing %a units to %a",0,units)
        end
        --
        local monospaced  = metadata.monospaced or metadata.isfixedpitch or (pfminfo.panose and pfminfo.panose.proportion == "Monospaced")
        local charwidth   = pfminfo.avgwidth -- or unset
        local charxheight = pfminfo.os2_xheight and pfminfo.os2_xheight > 0 and pfminfo.os2_xheight
-- charwidth = charwidth * units/1000
-- charxheight = charxheight * units/1000
        local italicangle = metadata.italicangle
        properties.monospaced  = monospaced
        parameters.italicangle = italicangle
        parameters.charwidth   = charwidth
        parameters.charxheight = charxheight
        --
        local space  = 0x0020
        local emdash = 0x2014
        if monospaced then
            if descriptions[space] then
                spaceunits, spacer = descriptions[space].width, "space"
            end
            if not spaceunits and descriptions[emdash] then
                spaceunits, spacer = descriptions[emdash].width, "emdash"
            end
            if not spaceunits and charwidth then
                spaceunits, spacer = charwidth, "charwidth"
            end
        else
            if descriptions[space] then
                spaceunits, spacer = descriptions[space].width, "space"
            end
            if not spaceunits and descriptions[emdash] then
                spaceunits, spacer = descriptions[emdash].width/2, "emdash/2"
            end
            if not spaceunits and charwidth then
                spaceunits, spacer = charwidth, "charwidth"
            end
        end
        spaceunits = tonumber(spaceunits) or 500 -- brrr
        --
        parameters.slant         = 0
        parameters.space         = spaceunits          -- 3.333 (cmr10)
        parameters.space_stretch = units/2   --  500   -- 1.666 (cmr10)
        parameters.space_shrink  = 1*units/3 --  333   -- 1.111 (cmr10)
        parameters.x_height      = 2*units/5 --  400
        parameters.quad          = units     -- 1000
        if spaceunits < 2*units/5 then
            -- todo: warning
        end
        if italicangle and italicangle ~= 0 then
            parameters.italicangle  = italicangle
            parameters.italicfactor = math.cos(math.rad(90+italicangle))
            parameters.slant        = - math.tan(italicangle*math.pi/180)
        end
        if monospaced then
            parameters.space_stretch = 0
            parameters.space_shrink  = 0
        elseif syncspace then --
            parameters.space_stretch = spaceunits/2
            parameters.space_shrink  = spaceunits/3
        end
        parameters.extra_space = parameters.space_shrink -- 1.111 (cmr10)
        if charxheight then
            parameters.x_height = charxheight
        else
            local x = 0x0078
            if x then
                local x = descriptions[x]
                if x then
                    parameters.x_height = x.height
                end
            end
        end
        --
        parameters.designsize    = (designsize/10)*65536
        parameters.minsize       = (minsize   /10)*65536
        parameters.maxsize       = (maxsize   /10)*65536
        parameters.ascender      = abs(metadata.ascender  or metadata.ascent  or 0)
        parameters.descender     = abs(metadata.descender or metadata.descent or 0)
        parameters.units         = units
        --
        properties.space         = spacer
        properties.encodingbytes = 2
        properties.format        = data.format or otf_format(filename) or formats.otf
        properties.noglyphnames  = true
        properties.filename      = filename
        properties.fontname      = fontname
        properties.fullname      = fullname
        properties.psname        = psname
        properties.name          = filename or fullname
        --
     -- properties.name          = specification.name
     -- properties.sub           = specification.sub
        --
        if warnings and #warnings > 0 then
            report_otf("warnings for font: %s",filename)
            report_otf()
            for i=1,#warnings do
                report_otf("  %s",warnings[i])
            end
            report_otf()
        end
        return {
            characters     = characters,
            descriptions   = descriptions,
            parameters     = parameters,
            mathparameters = mathparameters,
            resources      = resources,
            properties     = properties,
            goodies        = goodies,
            warnings       = warnings,
        }
    end
end

local function otftotfm(specification)
    local cache_id = specification.hash
    local tfmdata  = containers.read(constructors.cache,cache_id)
    if not tfmdata then
        local name     = specification.name
        local sub      = specification.sub
        local filename = specification.filename
     -- local format   = specification.format
        local features = specification.features.normal
        local rawdata  = otf.load(filename,sub,features and features.featurefile)
        if rawdata and next(rawdata) then
            local descriptions = rawdata.descriptions
            local duplicates = rawdata.resources.duplicates
            if duplicates then
                local nofduplicates, nofduplicated = 0, 0
                for parent, list in next, duplicates do
                    if type(list) == "table" then
                        local n = #list
                        for i=1,n do
                            local unicode = list[i]
                            if not descriptions[unicode] then
                                descriptions[unicode] = descriptions[parent] -- or copy
                                nofduplicated = nofduplicated + 1
                            end
                        end
                        nofduplicates = nofduplicates + n
                    else
                        if not descriptions[list] then
                            descriptions[list] = descriptions[parent] -- or copy
                            nofduplicated = nofduplicated + 1
                        end
                        nofduplicates = nofduplicates + 1
                    end
                end
                if trace_otf and nofduplicated ~= nofduplicates then
                    report_otf("%i extra duplicates copied out of %i",nofduplicated,nofduplicates)
                end
            end
            rawdata.lookuphash = { }
            tfmdata = copytotfm(rawdata,cache_id)
            if tfmdata and next(tfmdata) then
                -- at this moment no characters are assigned yet, only empty slots
                local features     = constructors.checkedfeatures("otf",features)
                local shared       = tfmdata.shared
                if not shared then
                    shared         = { }
                    tfmdata.shared = shared
                end
                shared.rawdata     = rawdata
             -- shared.features    = features -- default
                shared.dynamics    = { }
             -- shared.processes   = { }
                tfmdata.changed    = { }
                shared.features    = features
                shared.processes   = otf.setfeatures(tfmdata,features)
            end
        end
        containers.write(constructors.cache,cache_id,tfmdata)
    end
    return tfmdata
end

local function read_from_otf(specification)
    local tfmdata = otftotfm(specification)
    if tfmdata then
        -- this late ? .. needs checking
        tfmdata.properties.name = specification.name
        tfmdata.properties.sub  = specification.sub
        --
        tfmdata = constructors.scale(tfmdata,specification)
        local allfeatures = tfmdata.shared.features or specification.features.normal
        constructors.applymanipulators("otf",tfmdata,allfeatures,trace_features,report_otf)
        constructors.setname(tfmdata,specification) -- only otf?
        fonts.loggers.register(tfmdata,file.suffix(specification.filename),specification)
    end
    return tfmdata
end

local function checkmathsize(tfmdata,mathsize)
    local mathdata = tfmdata.shared.rawdata.metadata.math
    local mathsize = tonumber(mathsize)
    if mathdata then -- we cannot use mathparameters as luatex will complain
        local parameters = tfmdata.parameters
        parameters.scriptpercentage       = mathdata.ScriptPercentScaleDown
        parameters.scriptscriptpercentage = mathdata.ScriptScriptPercentScaleDown
        parameters.mathsize               = mathsize
    end
end

registerotffeature {
    name         = "mathsize",
    description  = "apply mathsize specified in the font",
    initializers = {
        base = checkmathsize,
        node = checkmathsize,
    }
}

-- helpers

function otf.collectlookups(rawdata,kind,script,language)
    local sequences = rawdata.resources.sequences
    if sequences then
        local featuremap, featurelist = { }, { }
        for s=1,#sequences do
            local sequence = sequences[s]
            local features = sequence.features
            features = features and features[kind]
            features = features and (features[script]   or features[default] or features[wildcard])
            features = features and (features[language] or features[default] or features[wildcard])
            if features then
                local subtables = sequence.subtables
                if subtables then
                    for s=1,#subtables do
                        local ss = subtables[s]
                        if not featuremap[s] then
                            featuremap[ss] = true
                            featurelist[#featurelist+1] = ss
                        end
                    end
                end
            end
        end
        if #featurelist > 0 then
            return featuremap, featurelist
        end
    end
    return nil, nil
end

-- readers (a bit messy, this forced so I might redo that bit: foo.ttf FOO.ttf foo.TTF FOO.TTF)

local function check_otf(forced,specification,suffix)
    local name = specification.name
    if forced then
        name = specification.forcedname -- messy
    end
    local fullname = findbinfile(name,suffix) or ""
    if fullname == "" then
        fullname = fonts.names.getfilename(name,suffix) or ""
    end
    if fullname ~= "" and not fonts.names.ignoredfile(fullname) then
        specification.filename = fullname
        return read_from_otf(specification)
    end
end

local function opentypereader(specification,suffix)
    local forced = specification.forced or ""
    if formats[forced] then
        return check_otf(true,specification,forced)
    else
        return check_otf(false,specification,suffix)
    end
end

readers.opentype = opentypereader -- kind of useless and obsolete

function readers.otf  (specification) return opentypereader(specification,"otf") end
function readers.ttf  (specification) return opentypereader(specification,"ttf") end
function readers.ttc  (specification) return opentypereader(specification,"ttf") end
function readers.dfont(specification) return opentypereader(specification,"ttf") end

-- this will be overloaded

function otf.scriptandlanguage(tfmdata,attr)
    local properties = tfmdata.properties
    return properties.script or "dflt", properties.language or "dflt"
end

-- a little bit of abstraction

local function justset(coverage,unicode,replacement)
    coverage[unicode] = replacement
end

otf.coverup = {
    stepkey = "subtables",
    actions = {
        substitution      = justset,
        alternate         = justset,
        multiple          = justset,
        ligature          = justset,
        kern              = justset,
        pair              = justset,
        chainsubstitution = justset,
        chainposition     = justset,
    },
    register = function(coverage,lookuptype,format,feature,n,descriptions,resources)
        local name = formatters["ctx_%s_%s_%s"](feature,lookuptype,n) -- we can have a mix of types
        if lookuptype == "kern" then
            resources.lookuptypes[name] = "position"
        else
            resources.lookuptypes[name] = lookuptype
        end
        for u, c in next, coverage do
            local description = descriptions[u]
            local slookups = description.slookups
            if slookups then
                slookups[name] = c
            else
                description.slookups = { [name] = c }
            end
        end
        return name
    end
}

-- moved from font-oth.lua

local function getgsub(tfmdata,k,kind)
    local description = tfmdata.descriptions[k]
    if description then
        local slookups = description.slookups -- we assume only slookups (we can always extend)
        if slookups then
            local shared = tfmdata.shared
            local rawdata = shared and shared.rawdata
            if rawdata then
                local lookuptypes = rawdata.resources.lookuptypes
                if lookuptypes then
                    local properties = tfmdata.properties
                    -- we could cache these
                    local validlookups, lookuplist = otf.collectlookups(rawdata,kind,properties.script,properties.language)
                    if validlookups then
                        for l=1,#lookuplist do
                            local lookup = lookuplist[l]
                            local found  = slookups[lookup]
                            if found then
                                return found, lookuptypes[lookup]
                            end
                        end
                    end
                end
            end
        end
    end
end

otf.getgsub = getgsub -- returns value, gsub_kind

function otf.getsubstitution(tfmdata,k,kind,value)
    local found, kind = getgsub(tfmdata,k,kind)
    if not found then
        --
    elseif kind == "substitution" then
        return found
    elseif kind == "alternate" then
        local choice = tonumber(value) or 1 -- no random here (yet)
        return found[choice] or found[1] or k
    end
    return k
end

otf.getalternate = otf.getsubstitution

function otf.getmultiple(tfmdata,k,kind)
    local found, kind = getgsub(tfmdata,k,kind)
    if found and kind == "multiple" then
        return found
    end
    return { k }
end

function otf.getkern(tfmdata,left,right,kind)
    local kerns = getgsub(tfmdata,left,kind or "kern",true) -- for now we use getsub
    if kerns then
        local found = kerns[right]
        local kind  = type(found)
        if kind == "table" then
            found = found[1][3] -- can be more clever
        elseif kind ~= "number" then
            found = false
        end
        if found then
            return found * tfmdata.parameters.factor
        end
    end
    return 0
end
