Senisim Module:Interlinear

local p = {}
local data = mw.loadData( 'Module:Interlinear/data' )
local gloss_override = {} -- for custom gloss abbreviations
local getArgs = require('Module:Arguments').getArgs
local yesno = require('Module:Yesno')

--------------------------
-- Almost-global variables
--------------------------
local glossing_type, displaying_messages, free_translation, msg, buffer

-------------------
-- General settings 
-------------------
local conf = { --settings
    WordSeparator = " \n\r\t", -- Don't replace with %s as this would include non-breaking spaces
    GlossAbbrPattern = "^([Ø0-9A-Z]+)$", -- this isn't a full regex, but a Lua pattern
    GlossAbbrBoundary = "-.;:<>‹›/\\~\+=%s%[%]()%_'",
    GlossExcludeTable = {I = true,}, --strings not be treated as glossing abbreviations
    GlossExcludePattern = '[0-9][0-9]+',
    GlossSmallCapsExclude = "^[AOPS]$", -- glossing abbreviations matching this pattern will not be rendered in small caps
    GlossingType = "label", -- if set to "label" gloss abbreviations are formatted as an <abbr> with the "label" appearing in a tooltip
                        -- if set to "wikilink" the abbreviation is formatted as a wikilink to the relevant wikipedia article
                        -- if set to "none" abbreviations aren't formatted at all
    ErrorCategory = "[[Category:Pages with errors in interlinear text]]",
    AmbiguousGlossCategory = "[[Category:Articles with ambiguous glossing abbreviations]]",
    MessageGlossingError = "Error(s) in interlinear glossing",
    combining_gender_numbers = "[0-9][0-9]?$", --e.g. G4 '4th gender' or CL7 'class 7'
    combining_gender_prefixes = {G = "gender", CL = "class"},
    combining_person = {["1"] = "first person", ["2"] = "second person", ["3"] = "third person"},
    combining_number = {S = "singular", SG = "singular", P = "plural", PL = "plural", D = "dual", DU = "dual", TRI = "trial"},
    combining_gender = {F = "feminine", M = "masculine", N = "neuter"},
    LowerCaseGlosses = {["1sg"] = true, ["2sg"] = true, ["3sg"] = true, ["1du"] = true, ["2du"] = true, ["3du"] = true, ["1pl"] = true, ["2pl"] = true,
    	["3pl"] = true, ["Fsg"] = true, ["Fpl"] = true, ["Msg"] = true, ["Mpl"] = true,}, -- these are the non-all-upper-case strings that will be recognised as glossing abbreviations
    ErrorHelpLocation = "Template:Interlinear",
}

---------------------
-- CSS styles and classes
---------------------
conf.style = { --CSS styles
    WordDiv = "float: left; margin-bottom: 0.3em;",
    WordMargin = "margin-right: 1em;",
    WordP = "margin: 0px;", -- the style for the word <p> elements
    GlossAbbr = "font-variant: small-caps; font-variant-numeric: oldstyle-nums; text-transform: lowercase; ", -- won't be applied to gloss abbreviations containing lower-case characters
    HiddenText = "display: none;",
    EndDiv = "clear: left; display: block;", -- style of the <div> element at the end of the interlinear display
    ErrorMessage = "font-size: inherit",
}
conf.class = { --CSS classes
	Interlinear = "interlinear",
	GlossAbbr  = "gloss-abbr",
    GlossAbbrAmb = "gloss-abbr-ambiguous",
    GlossAbbrError = "gloss-abbr-error",
    ErrorMessage = "error",
}

---------------------
-- Sundry small functions
---------------------
local function normalise(str)
    return mw.ustring.gsub(str,"[" .. conf.WordSeparator .. "]+"," ")
end

local function tidyCss(str)
    str = mw.ustring.gsub(str, '^[\"\']*(.-)[\"\']*$', "%1") -- trims quotation marks
    if mw.ustring.sub(str, -1) ~= ";" then str = str .. ";" end -- appends ";" if missing
    return str
end

local function highlight(text)
	if text then
		return '<span style="color:#C00;font-weight:bold;">' .. text .. '</span>'
	else return "" end
end

local function tone_sup(str)
	return mw.ustring.gsub(str, "([^%p%s0-9])([0-9])", "%1<sup>%2</sup>")
end

local function is_empty(str) -- returns "false" if its argument is a string containing chars other than spaces &c.
    if not str then return true end
    if mw.ustring.find(str, "[^" .. conf.WordSeparator .. "]")
        then return false
    else return true end
end

local function help_link (anchor)
    if anchor then
        return " ([[" .. conf.ErrorHelpLocation .. "#" .. anchor .. "|help]])"
    else return "" end
end

--------------------
-- The following two functions update the glossing settings based on the received
-- template arguments. set_global_glossing_settings() updates the global settings
-- that are valid for all gloss abbreviations. set_glossing_type()
-- returns the glossing type, which can vary between the different lines.
--------------------
local function set_global_glossing_settings(a)
    local style = ""
    if a.style then style = tidyCss(a.style) end
    if a.underline == "no" then
        style = style .. "text-decoration: none;" end
    if a.small_caps == "no" then
        style = style .. "font-variant:normal; text-transform: none;" end
    if style ~= "" then conf.style.GlossAbbr = conf.style.GlossAbbr .. style end
end

local function set_glossing_type(glossing)
    if glossing then
		local GlossingType
        glossing = mw.ustring.lower(mw.text.trim(glossing))
        if mw.ustring.find(glossing, 'link') then
            GlossingType = "wikilink"
        elseif mw.ustring.find(glossing, 'label')
        	or  mw.ustring.find(glossing, 'no link') then
            GlossingType = 'label'
        elseif mw.ustring.find(glossing, 'no abbr') then
            GlossingType = "no abbr"
        elseif yesno(glossing) == false then
            GlossingType = nil
        elseif yesno(glossing) then
            GlossingType = conf.GlossingType
        else
            msg:add('error', 'Glossing type "' .. glossing .. '" not recognised') end
		return GlossingType
    else error("set_glossing_type: 'glossing' is nil or false", 2)
    end
end

local function set_custom_glosses(list)
    local abbs = mw.text.split(list, '[;\n\t]')
    for _,v in pairs(abbs) do
        local gloss = mw.text.split(v, ':')
        local a = mw.text.trim(gloss[1])
        if a and a ~= "" then
            gloss_override[a] = {}
            gloss_override[a].expansion = gloss[2]
            gloss_override[a].wikipage = gloss[3]
        end
    end
end

---------------------
-- The UserMessages object contains and processes error messages and warnings
---------------------
local UserMessages = {errors = {}, warnings = {}, gloss_messages = {}}
function UserMessages:add(msgtype, text, gloss)
    if msgtype == "gloss_message" then
        self.gloss_messages[gloss] = text
    elseif msgtype == "warning" then
        table.insert(self.warnings, text)
    elseif msgtype == "non-repeating error" then
        self.errors.nre = text
    elseif msgtype == "ambiguous gloss" then
        self.if_ambiguous_glosses = true
    elseif msgtype == "error" then
        table.insert(self.errors, text)
    else return error("UserMessages:add(): unknown message type", 2)
    end
end
function UserMessages:print_errors()
    local out = ""
    local namespace = mw.title.getCurrentTitle().namespace
    if next(self.errors) or self.warnings[1] then
        local err_span = mw.html.create("span")
        err_span:attr("style", conf.style.ErrorMessage)
        err_span:addClass(conf.class.ErrorMessage)
    	for _,v in pairs(self.errors) do
    		err_span:wikitext(" " .. v .. ";") end
    	if namespace % 2 == 0 and namespace ~= 2 -- non-talk namespaces, excluding user pages; if modifying please update the description on the category page
            then err_span:wikitext(conf.ErrorCategory)
        end
        out = tostring(err_span)
    	mw.addWarning(conf.MessageGlossingError)
    end
    if self.if_ambiguous_glosses then
    	if namespace == 0 -- article namespace
           then out = out .. conf.AmbiguousGlossCategory -- this category will only track articles
        end
    end
    return out
end
function UserMessages:print_warnings()
    local out = ""
    -- Messages and warnings get displayed only if the page is being viewed in "preview" mode:
    if displaying_messages and (next(self.gloss_messages) or next(self.warnings)) then
        local div = mw.html.create("div")
        div:addClass("messagebox")
        	:css("margin", "inherit")
            :wikitext("<i>This message box is shown only in preview:</i>")
            :newline()
        for _,v in ipairs(self.warnings) do
        	local p = div:tag("p")
        	p:addClass(conf.class.ErrorMessage)
        	p:attr("style", conf.style.ErrorMessage)
        	p:wikitext(v)
        end
        if self.gloss_messages then
        	div:wikitext("<p>  To change any of the following default expansions, see [[Template:Interlinear/doc#Custom abbreviations|the template's documentation]]:</p>")
        	end
        for _,v in pairs(self.gloss_messages) do
            div:wikitext("<p>" .. v .. "</p>")
        end
        out = out .. "\n\n" .. tostring(div)
    end
    return out
end

---------------------
-- gloss_lookup() receives a gloss abbreviation and tries to uncover its meaning.
---------------------
local function gloss_lookup(a, label, wikilink)
    local _label, _wikilink, _lookup = nil, nil, nil
    if gloss_override[a] then _lookup = gloss_override[a]
    elseif data.abbreviations[a] then _lookup = data.abbreviations[a] end
    if _lookup and _lookup.expansion ~= "" then
        _label, _wikilink = _lookup.expansion, _lookup.wikipage
    else
    	local prefix = mw.ustring.sub(a,1,1)
    	local suffix = mw.ustring.sub(a,2)
    	if conf.combining_person[prefix] then -- is it of the form 1PL or 3FS?
    		_label = conf.combining_person[prefix]
		local _suffix = conf.combining_number[suffix] or conf.combining_gender[suffix]
    		if _suffix then
    			_label = _label .. ", " .. _suffix
    		else
    			local suffix1 = mw.ustring.sub(suffix,1,1)
    			local suffix2 = mw.ustring.sub(suffix,2)
    				if conf.combining_gender[suffix1]
    				and  conf.combining_number[suffix2] then
    					_label = _label .. ", " .. conf.combining_gender[suffix1] .. ", " .. conf.combining_number[suffix2]
    				else _label = nil end
    		end
	elseif mw.ustring.match(suffix,conf.combining_gender_numbers) then -- cases like G4 = gender 4
		local _i,_j = mw.ustring.find(a, conf.combining_gender_numbers)
		local _pre = mw.ustring.sub(a, 1, _i - 1)
		local _suff = mw.ustring.sub(a, _i)
		if conf.combining_gender_prefixes[_pre] then
			_label = conf.combining_gender_prefixes[_pre] .. " " .. _suff
		end
	elseif prefix == "N" then -- dealing with cases like NPST = non-past
		local s = gloss_override[suffix] or data.abbreviations[suffix]
        	if s ~= nil and not s.ExcludeNegation then
        	    _label = "non-" .. s.expansion
    	     _wikilink = s.wikipage
    		end
    		s = nil
    	end
    end
    if _label == "" then _label = nil end
    if _wikilink == "" then _wikilink = nil end
    if not label then label = _label end
    if not wikilink then wikilink = _wikilink end
    return label, wikilink
end

---------------------
-- format_gloss() calls gloss_lookup() to find the meaning of a gloss
-- abbreviation, which it then proceeds to format
---------------------
local function format_gloss(gloss, label, wikilink)
	local gloss2 = mw.ustring.gsub(gloss,"<.->","") -- remove any html fluff
    gloss2 = mw.ustring.gsub(gloss2, "%'%'+", "") -- remove wiki bold/italic formatting
    gloss2 = mw.text.trim(mw.ustring.upper(gloss2))
    if not (label or wikilink)
        or (not label and glossing_type == "label")
        or (not wikilink  and glossing_type == "wikilink")
        then
            if glossing_type ~= "no abbr"
                then label, wikilink = gloss_lookup(gloss2, label, wikilink)
            end
    end
    local gloss_node
    if glossing_type == "no abbr"
        then gloss_node = mw.html.create("span")
    else gloss_node = mw.html.create("abbr") end
    gloss_node:addClass(conf.class.GlossAbbr)
    if label or wikilink then
        if not mw.ustring.match(gloss, "%l") -- excluding glosses that contain lower-case characters
            and not mw.ustring.match(gloss,conf.GlossSmallCapsExclude) -- and also excluding A, O etc. from rendering in small caps
            then gloss_node:attr("style", conf.style.GlossAbbr)
        end
        local abbr_label
        if label then abbr_label = label
            else abbr_label = wikilink end
        gloss_node:attr("title", abbr_label)
    	if data.abbreviations[gloss2] then
    		if data.abbreviations[gloss2].ambiguous then
    			gloss_node:addClass(conf.class.GlossAbbrAmb)
                    msg:add("ambiguous gloss")
                end
        end
        if glossing_type == "wikilink" and wikilink
        	then gloss_node:wikitext("[[", wikilink, "|" , gloss, "]]")
        	else gloss_node:wikitext(gloss) end
        if displaying_messages then -- logging gloss lookups:
        	local message = ""
        	if label then
        		message = "assuming " .. gloss2 .. " means \"" .. abbr_label .. "\";" end
    		if glossing_type == "wikilink" and wikilink then
    			message = message .. " linking to [[" .. wikilink .. "]];"
    		end
    		msg:add("gloss_message", message, gloss)
        end
    elseif glossing_type == "no abbr"
        then gloss_node
                :attr("style", conf.style.GlossAbbr)
                :wikitext(gloss)
    else
    	if displaying_messages then
    		msg:add("warning", "Gloss abbreviation " .. highlight(gloss2) .. "  not recognised" .. help_link("gloss abbr"))
        end
        msg:add("non-repeating error", "Unknown glossing abbreviation(s)" .. help_link("gloss abbr"))
        gloss_node
            :addClass(conf.class.GlossAbbrError)
            :addClass("error")
            :css("font-size", "100%")
            :attr("title", gloss2 .. ": glossing abbreviation not found")
            :attr("style", conf.style.ErrorMessage)
            :wikitext(gloss)
    end
    return tostring(gloss_node)
end

---------------------
-- find_gloss() parses a word into morphemes, and it calls format_gloss()
-- for anything that looks like a glossing abbreviation.
---------------------
local function find_gloss(word)
    local function scan_gloss(boundary, gloss_abbr) -- checks a morpheme if it is a gloss abbreviation
        if (mw.ustring.match(gloss_abbr, conf.GlossAbbrPattern)
            or conf.LowerCaseGlosses[gloss_abbr])
            and not (conf.GlossExcludeTable[gloss_abbr]
                or mw.ustring.match(gloss_abbr, conf.GlossExcludePattern))
            then gloss_abbr = format_gloss(gloss_abbr)
        end
        return boundary .. gloss_abbr
    end
    local word = mw.text.decode(word, true)
    if word == "I" -- for the case of the English word "I", the 1SG pronoun
        then return word end
    local pattern = "([" .. conf.GlossAbbrBoundary .. "]?)([^" .. conf.GlossAbbrBoundary .. "]+)"
    word = mw.ustring.gsub(word, pattern, scan_gloss) -- splits into morphemes
    return word
end

---------------------
-- The main purpose of the bletcherous parse() is to split a line into words and and then for each eligible word
-- to call find_gloss(). The parser outputs the individual words (with any gloss abbreviation formatting applied).
-- The simple job of splitting at whitespaces has been made complicated by a) the fact that the input can contain
-- whitespaces inside the various html elements that are the result of the application of various formatting templates;
-- and b) the need to be able to recognise the output of the template that formats custom gloss abbreviations
-- (and hence skip passing it on to find_gloss). See talk for a suggestion about its future.
---------------------
local function parse(cline, i, tags_found,ifglossing)

    local function issue_error(message, culprit)
    	UserMessages:add("error",  message .. ": ''" .. mw.ustring.sub(cline.whole, 1, i-1) .. "'''" .. culprit  .. "'''''")
    end
    if i > cline.length then return i end --this will only be triggered if the current line has less words than line 1
    local next_step, j, _, chunk
    local probe = mw.ustring.sub(cline.whole,i,i)
    if mw.ustring.match(probe,"[" .. conf.WordSeparator .. "]") and tags_found == 0
        then next_step =  i-1
    elseif probe == "[" then --Wikilink?
        if mw.ustring.sub(cline.whole,i+1,i+1) == "[" then
        	_,j,chunk = mw.ustring.find(cline.whole,"(%[%[.-%]%])", i)
        else chunk = "["; j = i end --not a wikilink then
        buffer = buffer .. chunk
        next_step =  parse(cline, j+1,tags_found,ifglossing)
    elseif probe == "{"  and tags_found == 0 then --curly brackets enclose a sequence of words to be treated as a single unit
    	_,j,chunk = mw.ustring.find(cline.whole,"(.-)(})", i+1)
    	if not chunk then
    		issue_error("Unclosed curly bracket", "{")
    		chunk = highlight("{"); j = i
        elseif ifglossing==true then
            chunk = find_gloss(chunk)
		else
			if cline.tone_sup then chunk = tone_sup(chunk) end
		end
    	buffer = buffer .. chunk
        next_step =  parse(cline, j+1,tags_found,ifglossing)
    elseif probe == "<" then -- We've encountered an HTML tag. What do we do now?
        local _,j,chunk = mw.ustring.find(cline.whole,"(<.->)",i)
        if not chunk then
        	issue_error("Unclosed angle bracket", "<")
        	chunk = highlight("<"); j = i
        elseif mw.ustring.sub(cline.whole,i,i+1) == "</" then -- It's a CLOSING tag
            if cline.glossing
                and ifglossing==false
                and mw.ustring.match(chunk,"</abbr>")
                then ifglossing=true end
            tags_found = tags_found - 1
        elseif not mw.ustring.match(chunk, "/>$") -- It's an OPENING tag, unless it opens a self-closing element (in which case the element is ignored)
            then if ifglossing == true -- the following checks for the output of {{ggl}}: 
                	and mw.ustring.find(chunk, conf.class.GlossAbbr, 1, true) -- it's important that the "find" function uses literal strings and not patterns
                		then ifglossing = false end
            tags_found = tags_found + 1
        end
        buffer = buffer .. chunk
        next_step = parse(cline, j+1,tags_found,ifglossing)
    else -- No HTML tags, so we only need to find where the word ends
        local _,k,chunk = mw.ustring.find(cline.whole,"(..-)([ <[])",i)
        if k then --ordinary text
            if ifglossing==true then
                buffer = buffer .. find_gloss(chunk)
			else
				if cline.tone_sup then chunk = tone_sup(chunk) end
				buffer = buffer .. chunk
            end
            next_step = parse(cline, k, tags_found, ifglossing)
        else -- reached end of string        
            if ifglossing == true then
                chunk = find_gloss(mw.ustring.sub(cline.whole,i))
            else
            	chunk = mw.ustring.sub(cline.whole,i)
            	if cline.tone_sup then chunk = tone_sup(chunk) end
            end
            buffer = buffer .. chunk
            next_step = cline.length
        end
    end
    return next_step
end
--------------------
-- The following function is called by Template:gcl and is used for formatting an individual glossing abbreviation
--------------------
function p.gcl(frame)
    local args = getArgs(frame,{
        trim = true,
        removeBlanks = false,
        parentOnly = true,
        wrappers = {'Template:Gcl'},
    })
    msg = UserMessages
    set_global_glossing_settings{style = args.style, underline = args.underline, small_caps = args['small-caps']}
    if not args.glossing then
        glossing_type = conf.GlossingType -- a global variable
    else glossing_type = set_glossing_type(args.glossing)
    end
    local gloss, label, wikilink = args[1], args[2], args[3]
    if not gloss then UserMessages:add("error", "No gloss supplied")
    	return UserMessages:print() end
    if wikilink and not args.glossing then -- if a wikilink is supplied and glossing isn't set to 'label'...
        glossing_type = 'wikilink' end --     .. then the wikilink will be formatted as such
    if label == "" then label = nil end
    if wikilink == "" then wikilink = nil end
    local result = format_gloss(gloss, label, wikilink)
    return result
end

--------------------
-- The following is the function called by Template:Interlinear.
-- It processes the template arguments, then calls parse() to split the input lines into words
-- and it then builds the output html.
--------------------
function p.interlinearise(frame)
---------------------
-- Prepare arguments
---------------------
    local args = getArgs(frame, { -- configuration for Module:Arguments
        trim = true,
        removeBlanks = false,
        parentFirst = true,
        wrappers = {'Template:Interlinear', 'Template:Fs interlinear'},
    })
    local template_name = frame:getParent():getTitle()
    if template_name == 'Template:Fs interlinear' then
        args.italics1 = args.italics1 or "no"
        args.italics2 = args.italics2 or "yes"
        args.glossing3 = args.glossing3 or "yes"
    end
    local revid = frame:preprocess( "{{REVISIONID}}" )
    if  revid == "" then
    	if not args['display-messages'] or yesno(args['display-messages']) then
        displaying_messages = true end-- messages will be displayed only in preview mode
    end 
    msg = UserMessages
    local line = {}
    
    local function set_italics(n)
        line[n].attr.style = line[n].attr.style .. "font-style: italic;"
    	line[n].tone_sup = true -- single digits are assumed to be tone markers and will hence be superscripted
    	if args['tone-superscripting'] and not yesno(args['tone-superscripting'])
            then line[n].tone_sup = false end
    end
    
    if args.glossing then -- the glossing= parameter sets the default glossing type
    	local _gl = set_glossing_type(args.glossing)
    	if _gl then conf.GlossingType = _gl end
    end
    local _ablist = args.abbreviations or args.ablist
    if _ablist and _ablist ~= ""
        then set_custom_glosses(_ablist) end
        
    local _spacing = tonumber(args.spacing)
    if _spacing and _spacing <= 20
        then conf.style.WordDiv = conf.style.WordDiv .. 'margin-right: ' .. _spacing .. 'em;'
    else conf.style.WordDiv = conf.style.WordDiv .. conf.style.WordMargin
    end
    
    local offset, last_line = 0, 0
    for j,v in ipairs(args) do -- iterates over the unnamed parameters from the template
        last_line = last_line +1
        if is_empty(v)
            then offset = offset + 1
        else
        local i = j - offset
        line[i] = {}
        v = normalise(v)
        line[i].whole = v
        line[i].length = mw.ustring.len(v)
        
        local _c = args["c" .. i]
        if _c and _c ~= "" then
            line.hasComments = true
            line[i].c = _c
        end
        
        ---prepare style arguments----
        line[i].class = ""
        local _style = args["style" .. i]
        if not _style then _style = ""
        else _style = tidyCss(_style) end
        --line[i].attr holds the attributes for the <p> elements that enclose the words in line i
        line[i].attr = {style = conf.style.WordP .. _style}
        
        local _lang = args["lang" .. i]
        if _lang and #_lang > 1 then
            line[i].attr.lang = _lang
        else _lang = args.lang
            if _lang and #_lang > 1 and i == 1 then -- if a lang= parameter is supplied, it's assumed to apply to line 1
                line[i].attr.lang = _lang
            end
        end
        
        if yesno(args["italics" .. i]) then
            set_italics(i)
        end
        
        local _glossing = args["glossing" .. i]
        if _glossing then
            line[i].glossing = set_glossing_type(_glossing)
            line.HasCustomGlossing = true
        end
        
        local _ipa = args['ipa' .. i]
        if yesno(_ipa) then
            line[i].class = "IPA"
        end
        
        local _class = args['class' .. i]
        if _class then
            line[i].class = line[i].class .. " " .. _class
        end
        
        if line[i].class == ""
            then line[i].class = nil end
        end -- ends the first if-statement in the loop
    end -- ends the FOR cycle

    local line_count = #line
    if line_count == 0 then
        msg:add("error", template_name .. ": no lines supplied.")
        return msg:print_errors()
    end
    
    if line_count > 1 then
    	local _italics = args.italics
    	local n = tonumber(_italics)
    	if n and n > 0 then
    		set_italics(n)
		 elseif yesno(_italics) ~= false 
		 and yesno(args["italics" .. 1]) ~= false then
		 	set_italics(1) -- by default, the first line will get italicised
    	end
        -- the last unnamed parameter is assumed to be the free translation:
        free_translation = args[last_line]
        if not is_empty(free_translation) then
        	line [line_count] = nil   end  --... and is thus excluded from interlinearising
    end

-- If glossing isn't specified for any line, then it's chosen by default to occur
-- in the second line, unless only a single line has been supplied, in which case
-- the assumption is that it is the one containing grammatical glosses
	if yesno(args.glossing) == false then
		line.HasCustomGlossing = true end
	if not line.HasCustomGlossing then
		if line_count == 1 then
	    	line[1].glossing = conf.GlossingType
		elseif line[2] then
    		line[2].glossing = conf.GlossingType
    	end
    end
    set_global_glossing_settings{style = args['glossing-style'], underline = args.underline, small_caps = args['small-caps']}

---------------------
-- Segment lines into words
---------------------
    for i,v in ipairs(line) do
    	local ifglossing = false
        if line[i].glossing then
        	ifglossing = true -- if true the parser will attempt to format gloss abbreviations in the current line
    		glossing_type = line[i].glossing -- neccessarily a global variable
    	end
        local wc, n = 1, 1
        line[i].words = {}
        while n <= line[i].length do
            buffer = ""
            n = parse(line[i], n, 0, ifglossing)+2
            line[i].words[wc] = buffer
            wc = wc + 1
        end
    end

    ----Check for mismatches in number of words across lines----
    local number_of_words, mismatch_found = 0, false
    for i,v in ipairs(line) do -- find the maximum number of words in any line
        local wc = #line[i].words
        if wc ~= number_of_words then
            if i ~= 1 and wc ~= 0 then
                mismatch_found = true
            end
            if wc > number_of_words then
                number_of_words = wc
            end
        end
    end
    ----Deal with mismatches---
    if mismatch_found then
        local error_text = "Mismatch in the number of words between lines: "
        for i,v in ipairs(line) do
            local wc = #line[i].words
            error_text = error_text .. wc .. " word(s) in line " .. i .. ", "
            if wc ~= number_of_words then
                for current_word = wc+1, number_of_words do
                    line[i].words[current_word] = "&nbsp;"
                end
            end
        end
        if string.sub(error_text, -2) == ", "
            then error_text = string.sub(error_text, 1, #error_text - 2) .. " "
        end
        error_text = error_text .. help_link("mismatch")
        UserMessages:add("error", error_text)
    end

---------------------
-- Build the HTML
---------------------
    ---- If just a single line was supplied, format it as inline text
    if line_count == 1 then
        local span = mw.html.create('span')
        span:attr(line[1].attr)
        for wi = 1, number_of_words do
            local space
            if wi < number_of_words then space = " " else space = "" end
            span:wikitext(line[1].words[wi] .. space)
        end
        return tostring(span)
    end
    
    ---- More than one line supplied, so we'll produce interlinear display
    local div = mw.html.create("div")
    div:addClass(conf.class.Interlinear)
    if args.box and args.box ~= "" then
    	div:css("background-color", "#f8f9fa")
    		:css("border", "1px solid #eaecf0")
			:css("padding", "1em") end
    if args.top and args.top ~= "" then --lines to display above the interlinear block
    	div:tag("div")
    		:wikitext(args.top)
    end
    
    -- Producing the interlinear block
    for wi = 1, number_of_words do
        local div2 = div:tag("div")
                    :attr("style", conf.style.WordDiv)
        for i,_ in ipairs (line) do
            if line[i].whole ~= "" then -- skipping empty lines
                local p = div2:tag("p")
                p:attr(line[i].attr)
                if line[i].class then
                    p:addClass(line[i].class)
                end
                local _text = line[i].words[wi]
                if _text == "" or _text == " " 
                	then _text = "&nbsp;" end -- <p> elements without content mess up the interlinear display
                p:wikitext(_text)
            end
        end
    end
    
    --- If any "comments" have been specified, add them at the end of each line
    if line.hasComments then
        local divc = div:tag("div")
                    :attr("style", conf.style.WordDiv)
        for i,_ in ipairs (line) do
            local p = divc:tag("p")
            p:attr("style", conf.style.WordP)
            if line[i].c then
                p:wikitext(line[i].c)
            else p:wikitext("&nbsp;")
            end
        end
    end
    
    --Add hidden lines containing the content of each line of interlinear text: this is for accessibility
    for i,v in ipairs(line) do
        local hidden_line = div:tag("p")
        hidden_line:attr("style", conf.style.HiddenText)
                    :wikitext(v.whole)
    end
    
    -- Format the free translation
    local ft_line = div:tag("p")
    if free_translation and free_translation ~= "" then
    	ft_line:attr("style", "clear: left;")
        ft_line:wikitext(free_translation)
    end
    if args.bottom and args.bottom ~= ""
        then local bottom = div:tag('p')
        bottom:css('margin-top', '0')
        bottom:wikitext(args.bottom)
    end
    ft_line:node(msg:print_errors()) -- for error messages
    
    local end_div = div:tag("div")
        end_div:attr("style", conf.style.EndDiv)
    div:newline()
    
    -- For stuff to be displayed in the left margin, like example numbering
    local before, number, indent = "", nil, nil
    if args.number and args.number ~= "" 
    	then number = args.number end
    if args.indent and args.indent ~=""
    	then indent = args.indent end
    if indent or number then
    	if not indent then indent = "3" end --default value
    	div:css("margin-left", indent .. 'em')
    	if number then 
    		before = '<div style="position:absolute; left:1em;">' .. args.number .. '</div>'
    	end
	end
    return  before .. tostring(div) .. msg:print_warnings()
end

return p