local p={} -- ultimate planned purpose is to create table rows of Refdesk questions, type, date, answerer including wikilinks in collaboration with a big template

function p.main(frame,input,label,desk,year,month,day,arcpage)

    local args=frame.args

    local parent=frame:getParent() or {}

    local pargs=parent.args or {}

    input=input or args.input or pargs.input

    desk=desk or args.desk or pargs.desk

    local label=label or args.label or pargs.label

    if not label then label=desk or "unlabelled" end

    local date=args.date or pargs.date or "undated"

    if year and month and day then date="20"..year..": "..month.." "..day end

    arcpage=arcpage or args.arcpage or pargs.arcpage or nil

    local cat=args.cat or pargs.cat or "yes"

    if cat=="no" then cat = nil end

    local output="[[Module:RDIndex]] error: no section headings found"



    local cursor, next_cursor, questioner, users, user_table, last_user;

    local input_length = mw.ustring.len( input );

    

    local breakpoints = {};

    local cut, item

    for cut, item in mw.ustring.gmatch( input, "\n()==+(.-)==+%s+" ) do                

        table.insert( breakpoints, cut );        

        table.insert( breakpoints, item );        

    end     

    

    index = 1;

    output = '';

    repeat

        cursor = tonumber( breakpointsindex );

        title = breakpointsindex + 1];

             

        if cursor == nil then 

            break;

        end

        next_cursor = tonumber( breakpointsindex+2 ) or input_length;

      

        text = mw.ustring.sub(input,cursor,next_cursor-1)

        tt = mw.ustring.match(title,"[=%s]+(.-)[=%s]+$")

        if tt then 

            title=tt 

        else

            tt = mw.ustring.match(title,"UNIQ.-QINU.(.+)")

            if tt then 

                title=tt 

            end

        end

        local tcat=""

        if cat then tcat = (mw.ustring.match(text,"{{[Rr][Dd]cat%s*|%s*(.-)}}") or "—") end

        tcat=mw.ustring.match(tcat,"^(^|*)|.*$") or tcat

        text = mw.ustring.gsub(text, "%[%[Special:Contributions/", "[[User:")

        questioner = mw.ustring.gsub(mw.ustring.match(text,"%[%[User:(.-)[|%]]") or "","_"," ")

        user_table = {}

        for tt in mw.ustring.gmatch(text,"%[%[User:(.-)[|%]]" ) do

            tt = mw.ustring.gsub(tt,"_"," ")

            table.insert( user_table, tt );

        end

        table.sort( user_table );

        

        last_user = ''

        users = '';

        for index, tt in pairs( user_table ) do

            if tt ~= last_user and tt ~= questioner then

                users = table.concat( {users, "[[User:", tt, "|", tt, "]]", " "} );

            end

            last_user = tt;

        end        

        users = "[[User:" .. questioner .. "|" .. questioner .. "]]" .. " " .. users

        title = mw.ustring.gsub( title, '%[%[.-|(.-)%]%]', '%1' );

        title = mw.ustring.gsub( title, '%[', '' );

        title = mw.ustring.gsub( title, '%]', '' );

        title = mw.ustring.gsub( title, '%b<>', '' );

        

        if arcpage then 

            title= table.concat( {"[[", arcpage, "#", (title or ""), "|", title,  "]]"} );

        else 

            title= title or "" 

        end

        if (cat=="yes" or cat==tcat) then output = table.concat( {output, "\n|-\n|", title, "\n|", next_cursor-cursor, "\n|", label, "\n|", tcat, "\n|", date, "\n|", users} ) end



        index = index + 2;

    until next_cursor == input_length

  

    return output

end



function p.month(frame)

    local args=frame.args

    local parent=frame:getParent() or {}

    local pargs=parent.args or {}

        local title

    if not input then title=mw.title.getCurrentTitle() end

    

    local year=args.year or pargs.year

    local month=args.month or pargs.month

    local desk=args.desk or pargs.desk

    local label=args.label or pargs.label or desk

    local nowiki=args.nowiki or pargs.nowiki

    local desks={'Computing','Science','Mathematics','Humanities','Language','Entertainment','Miscellaneous'}

    local months={'January','February','March','April','May','June','July','August','September','October','November','December'}

    local days=31

    local output=""

    if not (desk and year and month) then -- I want to be able to plop this template empty of parameters into an archive page, even if it moves, as long as its name contains the data!

        local title=mw.title.getCurrentTitle()

        local page=title.fullText

        if not desk then

            for x=1,#desks do

                if mw.ustring.match(page,desksx]) then desk=desksx]; break end

            end

        end

        year=year or mw.ustring.match(page,"20(%d%d)") -- This has a Y2.1k bug.  Pity.

        if not month then

            for x=1,12 do

                if mw.ustring.match(page,monthsx]) then month=monthsx]; break end

            end

        end

    end

    year=tonumber(year)

    if month=='September' or month=='April' or month=='June' or month=='November' then days=30 end

    if month=='February' then

        days=28

        if year/4==math.floor(year/4) then days=29 end

    end

    for day=1,days do

        page='Wikipedia:Reference desk/Archives/'..desk..'/20'..year..' '..month..' '..day

        title=mw.title.new(page)

        if title then

            local input=title.getContent(title)

            if input then output=output..p.main(frame,input,label,desk,year,month,day,page) end

        end

    end

    output='{| class="wikitable sortable"\n!question\n!length\n!RefDesk\n!Category\n!Date\n!Editors'..output..'\n|}'

    if nowiki then

       return frame:preprocess("<pre><nowiki>"..output.."</nowiki></pre>")

    else

       return output

    end

end



return p