local export = {}

-- Part of speech types that should not be pluralized.
local invariable = mw.loadData("Module:headword/data").invariable

function export.head_t(frame)
	local plain_param = {}
	local list_with_holes = {list = true, allow_holes = true}
	local boolean_list_with_holes = {list = true, allow_holes = true, type = "boolean"}
	local params = {
		 = {required = true, default = "und"},
		 = plain_param,
		 = plain_param,
		
		 = {required = true, default = "nouns"},
		 = {type = "boolean"},
		 = {type = "boolean"},
		 = {type = "boolean"},
		 = {type = "boolean"},
		 = {type = "boolean"},
		 = {type = "boolean"},
		 = plain_param,
		 = plain_param,
		 = plain_param,
		
		 = {list = true, allow_holes = true, default = ""},
		 = plain_param,
		 = list_with_holes,
		 = list_with_holes,
		 = {list = true},
		 = list_with_holes,
		
		 = list_with_holes,
		
		     = list_with_holes,
		 = list_with_holes,
		    = list_with_holes,
		 = list_with_holes,
		   = list_with_holes,
		  = boolean_list_with_holes,
		        = list_with_holes,
		            = list_with_holes,
		             = list_with_holes,
		             = list_with_holes,
		             = list_with_holes,
		             = list_with_holes,
		              = list_with_holes,
		           = list_with_holes,
		         = boolean_list_with_holes,
		         = boolean_list_with_holes,
		           = list_with_holes,
	}
	
	local args = require("Module:parameters").process(frame:getParent().args, params)
	
	-- Get language and script information
	local data = {}
	data.lang = require("Module:languages").getByCode(args) or require("Module:languages").err(args, 1)
	data.sort_key = args
	data.heads = args
	data.id = args
	data.translits = args
	data.transcriptions = args
	data.genders = args
	for k, v in pairs(args) do
		if k ~= "maxindex" then
			if data.genders then
				data.genders = {spec = data.genders, qualifiers = {v}}
			else
				k = k == 1 and "" or tostring(k)
				error(("g%squal= specified without g%s="):format(k, k))
			end
		end
	end

	-- Script
	data.sc = args and require("Module:scripts").getByCode(args, "sc") or nil
	data.sccat = args

	-- Part-of-speech category
	data.pos_category = args
	data.noposcat = args
	
	if not data.pos_category:find("s$") and not invariable then
		-- Make the plural form of the part of speech
		if data.pos_category:find("x$") then -- prefix, suffix, confix, infix, circumfix, affix, interfix, transfix
			data.pos_category = data.pos_category .. "es"
		else
			data.pos_category = data.pos_category .. "s"
		end
	end
	
	-- Additional categories
	data.categories = {}
	data.nomultiwordcat = args
	data.nogendercat = args
	data.nopalindromecat = args
	
	if args then
		table.insert(data.categories, data.lang:getCanonicalName() .. " " .. args)
	end
	
	if args then
		table.insert(data.categories, data.lang:getCanonicalName() .. " " .. args)
	end
	
	if args then
		table.insert(data.categories, data.lang:getCanonicalName() .. " " .. args)
	end
	
	-- Inflected forms
	data.inflections = {enable_auto_translit = args}
	
	for i = 1, math.ceil(args.maxindex / 2) do
		local infl_part = {
			label    = args,
			accel    = args and {
				form      = args,
				translit  = args,
				lemma     = args,
				lemma_translit = args,
				gender    = args,
				nostore   = args,
			} or nil,
			request  = args,
			enable_auto_translit = args,
		}
		
		local form = {
			term          =  args,
			alt           =  args,
			genders       =  args and mw.text.split(args, ",") or {},
			id            =  args,
			lang          =  args,
			nolink        =  args,
			qualifiers    = {args},
			sc            =  args,
			translit      =  args,
			transcription =  args,
		}
		
		if form.lang then
			form.lang = require("Module:languages").getByCode(form.lang) or require("Module:languages").err(form.lang, "f" .. i .. "lang")
		end
		
		if form.sc then
			form.sc = require("Module:scripts").getByCode(form.sc) or error("The script code \"" .. form.sc .. "\" is not valid.")
		end
		
		-- If no term or alt is given, then the label is shown alone.
		if form.term or form.alt then
			table.insert(infl_part, form)
		end
		
		if infl_part.label == "or" then
			-- Append to the previous inflection part, if one exists
			if #infl_part > 0 and data.inflections then
				table.insert(data.inflections, form)
			end
		elseif infl_part.label then
			-- Add a new inflection part
			table.insert(data.inflections, infl_part)
		end
	end
	
	return require("Module:headword").full_headword(data)
end

return export