--
-- luatexja/otf.lua
--
luatexbase.provides_module({
  name = 'luatexja.otf',
  date = '2013/05/11',
  description = 'The OTF Lua module for LuaTeX-ja',
})

luatexja.load_module('base');      local ltjb = luatexja.base
luatexja.load_module('jfont');     local ltjf = luatexja.jfont
luatexja.load_module('rmlgbm');    local ltjr = luatexja.rmlgbm

local id_glyph = node.id('glyph')
local id_whatsit = node.id('whatsit')
local sid_user = node.subtype('user_defined')

local node_new = node.new
local node_remove = node.remove
local node_next = node.next
local node_free = node.free
local has_attr = node.has_attribute
local set_attr = node.set_attribute
local unset_attr = node.unset_attribute
local node_insert_after = node.insert_after

local attr_curjfnt = luatexbase.attributes['ltj@curjfnt']
local attr_jchar_class = luatexbase.attributes['ltj@charclass']
local attr_yablshift = luatexbase.attributes['ltj@yablshift']
local attr_ykblshift = luatexbase.attributes['ltj@ykblshift']

local ltjf_font_metric_table = ltjf.font_metric_table
local ltjf_find_char_class = ltjf.find_char_class
local ltjr_cidfont_data = ltjr.cidfont_data

local OTF = luatexja.userid_table.OTF

local function get_ucs_from_rmlgbm(c)
   local v = ltjr_cidfont_data["Adobe-Japan1"].resources.unicodes["Japan1." .. tostring(c)]
   if not v then -- AJ1 範囲外
      return 0
   elseif v<0xF0000 then -- 素直に Unicode にマップ可能
      return v
   else
      local w = ltjr_cidfont_data["Adobe-Japan1"].characters[v]. tounicode
      -- must be non-nil!
      local i = string.len(w)
      if i==4 then -- UCS2
         return tonumber(w,16)
      elseif i==8 then 
         i,w = tonumber(string.sub(w,1,4),16), tonumber(string.sub(w,-4),16)
         if (w>=0xD800) and (w<=0xDB7F) and (i>=0xDC00) and (i<=0xDFFF) then -- Surrogate pair
            return (w-0xD800)*0x400 + (i-0xDC00)
         else
            return 0
         end
      end
   end
end

-- Append a whatsit node to the list.
-- This whatsit node will be extracted to a glyph_node
local function append_jglyph(char)
   local p = node_new(id_whatsit,sid_user)
   local v = tex.attribute[attr_curjfnt]
   p.user_id=OTF; p.type=100; p.value=char
   set_attr(p, attr_yablshift, tex.attribute[attr_ykblshift])
   node.write(p)
end

local function cid(key)
   if key==0 then return append_jglyph(char) end
   local curjfnt = fonts.hashes.identifiers[tex.attribute[attr_curjfnt]]
   if not curjfnt.cidinfo or 
      curjfnt.cidinfo.ordering ~= "Japan1" and
      curjfnt.cidinfo.ordering ~= "GB1" and
      curjfnt.cidinfo.ordering ~= "CNS1" and
      curjfnt.cidinfo.ordering ~= "Korea1" then
--      ltjb.package_warning('luatexja-otf',
--			   'Current Japanese font (or other CJK font) "'
--			      ..curjfnt.psname..'" is not a CID-Keyed font (Adobe-Japan1 etc.)')
      return append_jglyph(get_ucs_from_rmlgbm(key))
   end
   local char = curjfnt.resources.unicodes[curjfnt.cidinfo.ordering..'.'..tostring(key)]
   if not char then
      ltjb.package_warning('luatexja-otf',
                           'Current Japanese font (or other CJK font) "'
                              ..curjfnt.psname..'" does not have the specified CID character ('
                              ..tostring(key)..')', 
                           'Use a font including the specified CID character.')
      char = 0
   end
   return append_jglyph(char)
end

local function extract(head)
   local p = head
   local v
   while p do
      if p.id==id_whatsit then
	 if p.subtype==sid_user and p.user_id==OTF then
	    local g = node_new(id_glyph)
	    g.subtype = 0; g.char = p.value
	    v = has_attr(p, attr_curjfnt); g.font = v
	    set_attr(g, attr_curjfnt, v)
	    v = has_attr(p, attr_yablshift)
	    if v then 
	       set_attr(g, attr_yablshift, v)
	    else
	       unset_attr(g, attr_yablshift)
	    end
	    head = node_insert_after(head, p, g)
	    head = node_remove(head, p)
	    node_free(p); p = g
	 end
      end
      p = node_next(p)
   end
   return head
end

luatexbase.add_to_callback('hpack_filter', 
   function (head) return extract(head) end,'ltj.hpack_filter_otf',
   luatexbase.priority_in_callback('pre_linebreak_filter',
				   'ltj.pre_linebreak_filter'))
luatexbase.add_to_callback('pre_linebreak_filter', 
   function (head) return extract(head) end, 'ltj.pre_linebreak_filter_otf',
   luatexbase.priority_in_callback('pre_linebreak_filter',
				   'ltj.pre_linebreak_filter'))


-- additional callbacks
-- 以下は，LuaTeX-ja に用意された callback のサンプルになっている．
--   JFM の文字クラスの指定の所で，"AJ1-xxx" 形式での指定を可能とした．
--   これらの文字指定は，和文フォント定義ごとに，それぞれのフォントの
--   CID <-> グリフ 対応状況による変換テーブルが用意される．

-- 和文フォント読み込み時に，CID -> unicode 対応をとっておく．
local function cid_to_char(fmtable, fn)
   local fi = fonts.hashes.identifiers[fn]
   if fi.cidinfo and fi.cidinfo.ordering == "Japan1" then
      fmtable.cid_char_type = {}
      for i, v in pairs(fmtable.chars) do
	 local j = string.match(i, "^AJ1%-([0-9]*)")
	 if j then
	    j = tonumber(fi.resources.unicodes['Japan1.'..tostring(j)])
	    if j then
	       fmtable.cid_char_type[j] = v 
	    end
	 end
      end
   end
   return fmtable
end
luatexbase.add_to_callback("luatexja.define_jfont", 
			   cid_to_char, "ltj.otf.define_jfont", 1)
--  既に読み込まれているフォントに対しても，同じことをやらないといけない
for fn, v in pairs(ltjf_font_metric_table) do
   ltjf_font_metric_table[fn] = cid_to_char(v, fn)
end


local function cid_set_char_class(arg, fmtable, char)
   if arg~=0 then return arg
   elseif fmtable.cid_char_type then
      return fmtable.cid_char_type[char] or 0
   else return 0
   end
end
luatexbase.add_to_callback("luatexja.find_char_class", 
			   cid_set_char_class, "ltj.otf.find_char_class", 1)

-------------------- all done
luatexja.otf = {
  append_jglyph = append_jglyph,
  cid = cid,
}

-- EOF