1 local st = require "stanza";

     2 local urlencode = require "net.http".urlencode;

     3 

     4 local xmlns_xhtmlim = "http://jabber.org/protocol/xhtml-im";

     5 local xmlns_xhtml = "http://www.w3.org/1999/xhtml";

     6 

     7 local function replace_latex(data)

     8 	module:log("debug", "Replacing latex...");

     9 	local origin, stanza = data.origin, data.stanza;

    10 	local body = stanza:child_with_name("body");

    11 	if not body then return; end

    12 	

    13 	body = body:get_text();

    14 	if not body:match("%$%$") then

    15 		return;

    16 	end

    17 	

    18 	local html = st.stanza("html", { xmlns = xmlns_xhtmlim })

    19 		:tag("body", { xmlns = xmlns_xhtml });

    20 		

    21 	local in_latex, last_char;

    22 	for snippet, up_to in body:gmatch("(.-)%$%$()") do

    23 		last_char = up_to;

    24 		if in_latex then

    25 			-- Render latex and add image, next snippet is text

    26 			in_latex = nil;

    27 			html:tag("img", { src = "http://www.mathtran.org/cgi-bin/mathtran?D=2;tex="..urlencode(snippet), alt = snippet }):up();

    28 		else

    29 			-- Add text to HTML, next snippet is latex

    30 			in_latex = true;

    31 			html:tag("span"):text(snippet):up();

    32 			

    33 		end

    34 	end

    35 	if last_char < #body then

    36 		html:tag("span"):text(body:sub(last_char, #body)):up();

    37 	end

    38 	

    39 	for n, tag in ipairs(stanza.tags) do

    40 		module:log("debug", "Tag: %s|%s", tag.attr.xmlns or "", tag.name or "");

    41 		if tag.name == "html" and tag.attr.xmlns == xmlns_xhtmlim then

    42 			stanza.tags[n] = html;

    43 			for n, child in ipairs(stanza) do

    44 				if child == tag then

    45 					stanza[n] = html;

    46 				end

    47 			end

    48 			return;

    49 		end

    50 	end

    51 	

    52 	stanza[#stanza+1] = html;

    53 	stanza.tags[#stanza.tags+1] = html;

    54 end

    55 

    56 module:hook("message/bare", replace_latex, 30);

    57 module:hook("message/full", replace_latex, 30);