local mkutils = require "mkutils" local log = logging.new("tocid") -- Unicode data distributed with ConTeXt -- defines "characters" table if not mkutils.isModuleAvailable("char-def") then log:warning("char-def module not found") log:warning("cannot fix section id's") return function(dom) return dom end end require "char-def" local chardata = characters.data or {} local toc = nil local function is_letter(info) -- test if character is letter local category = info.category or "" return category:match("^l") end local function is_space(info) local category = info.category or "" return category == "zs" end local uchar = utf8.char local function normalize_letter(char, result) local info = chardata[char] or {} -- first get lower case of the letter local lowercase = info.lccode or char -- remove accents. the base letter is in the shcode field local lowerinfo = chardata[lowercase] or {} -- when no shcode, use the current lowercase char local shcode = lowerinfo.shcode or lowercase -- shcode can be table if it contains multiple characters -- normaliz it to a table, so we can add all letters to -- the resulting string if type(shcode) ~= "table" then shcode = {shcode} end for _, x in ipairs(shcode) do result[#result+1] = uchar(x) end end local escape_name = function(name) local result = {} -- remove LaTeX commands name = name:gsub("\\[%a]+", "") name = name:gsub("^%s+", ""):gsub("%s+$", "") for _,char in utf8.codes(name) do local info = chardata[char] or {} if is_space(info) then result[#result+1] = " " elseif is_letter(info) then normalize_letter(char, result) end end --- convert table with normalized characters to string local name = table.concat(result) -- remove spaces name = name:gsub("%s+", "-") name = name:gsub("^%-", "") return name end local function parse_toc_line(line) -- the section ids and titles are saved in the following format: -- \csname a:TocLink\endcsname{1}{x1-20001}{QQ2-1-2}{Nazdar světe} -- ............................... id ................. title ... local id, name = line:match("a:TocLink.-{.-}{(.-)}{.-}(%b{})") if id then return id, escape_name(name) end end local used = {} local function parse_toc(filename) local toc = {} if not mkutils.file_exists(filename) then return nil, "Cannot open TOC file " .. filename end for line in io.lines(filename) do local id, name = parse_toc_line(line) -- if section name doesn't contain any text, it would lead to id which contains only number -- this is invalid in HTML if name == "" then name = "_" end local orig_name = name -- not all lines in the .4tc file contains TOC entries if id then -- test if the same name was used already. user should be notified if used[name] then -- update name = name .. used[name] log:debug("Duplicate id found: ".. orig_name .. ". New id: " .. name) end used[orig_name] = (used[orig_name] or 0) + 1 toc[id] = name end end return toc end -- we don't want to change the original id, as there may be links to it from the outside -- so we will set it to the parent element (which should be h[1-6]) local function set_id(el, id) local section = el:get_parent() local section_id = section:get_attribute("id") if section_id and section_id~=id then -- if it already has id, we don't override it, but create dummy child instead local new = section:create_element("span", {id=id}) section:add_child_node(new,1) else section:set_attribute("id", id) end end -- we want to remove elements from some elements, most notably
local elements_to_remove = { figure = true, figcaption } local function remove_a(el, parent, id) parent:set_attribute("id", id) el:remove_node() end return function(dom, par) local msg toc, msg = toc or parse_toc(mkutils.file_in_builddir(par.input .. ".4tc", par)) msg = msg or "Cannot load TOC" -- don't do anyting if toc cannot be found if not toc then log:warning(msg) return dom end -- if user selects the "notoc" option on the command line, we -- will not update href links local notoc = false if par["tex4ht_sty_par"]:match("notoc") then notoc = true end -- the HTML file can already contain ID that we want to assign -- we will not set duplicate id from TOC in that case local toc_ids = {} for _, el in ipairs(dom:query_selector("[id]")) do local id = el:get_attribute("id") toc_ids[id] = true end -- process all elements with id atribute or for _, el in ipairs(dom:query_selector "[id],a[href]") do local id, href = el:get_attribute("id"), el:get_attribute("href") if id then local name = toc[id] local parent = el:get_parent() -- remove unnecessary elements if the parent doesn't have id yet if elements_to_remove[parent:get_element_name()] and not parent:get_attribute("id") and el:get_element_name() == "a" then remove_a(el, parent, id) set_id(el, name) -- replace id with new section id elseif name and not toc_ids[name] then set_id(el, name) else if name then log:debug("Document already contains id: " .. name) end end end if href and notoc == false then -- replace links to sections with new id local base, anchor = href:match("^(.*)%#(.+)") local name = toc[anchor] if name then el:set_attribute("href", base .. "#" .. name) end end end return dom end