-- support magic comments used by TeXShop and TeXWorks to detect used engine and format
--
local M = {}
local log = logging.new("detect engine")
local htlatex = require "make4ht-htlatex"
local function find_magic_program(filename)
-- find the magic line containing program name
local get_comment = function(line)
return line:match("%s*%%%s*(.+)")
end
local empty_line = function(line) return line:match("^%s*$") end
for line in io.lines(filename) do
local comment = get_comment(line)
-- read line after line from the file, break the processing after first non comment or non empty line
if not comment and not empty_line(line) then return nil, "Cannot find program name" end
comment = comment or "" -- comment is nil for empty lines
local program = comment:match("!%s*[Tt][Ee][Xx].-program%s*=%s*([^%s]+)")
if program then return program:lower() end
end
end
-- update htlatex entries with detected program
local function update_build_sequence(program, build_seq)
-- handle Plain TeX
local replaces = change_table[program] or {}
local is_xetex = program:match("xe") -- we must handle xetex in tex4ht
for pos, entry in ipairs(build_seq) do
if entry.name == "htlatex" then
-- handle httex
entry.command = replaces.command or entry.command
local params = entry.params or {}
params.htlatex = replaces.htlatex or params.htlatex
entry.params = params
elseif is_xetex and entry.name == "tex4ht" then
-- tex4ht must process .xdv file if the TeX file was compiled by XeTeX
entry.params.tex4ht_par = entry.params.tex4ht_par .. " -.xdv"
end
end
end
function M.modify_build(make)
-- find magic comments in the TeX file
local build_seq = make.build_seq
local tex_file = make.params.tex_file
local program, msg = find_magic_program(tex_file)
if program then
log:info("Found program name", program)
update_build_sequence(program, build_seq)
else
log:warning("Cannot find magic line with the program name")
end
return make
end
