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local lang = require("Module:languages").getByCode("sje")

local export = {}


-- Inflection functions

function export.even(frame)
	local fparams = {
		[1] = {required = true},
		
		["nograd"] = {type = "boolean"},
	}
	
	local fargs = require("Module:parameters").process(frame.args, fparams)
	
	local params = {
		[1] = {required = true, default = "{{{1}}}"},
		
		["attr"] = fargs[1] == "adjectives" and {list = true} or nil,
		["n"] = fargs[1] == "nouns" and {} or nil,
		["novowel"] = {type = "boolean"},
	}
	
	local args = require("Module:parameters").process(frame:getParent().args, params)
	local stem = require("Module:sje-common").Stem(args[1], not fargs["nograd"])
	
	local data = {
		has_attr = fargs[1] == "adjectives",
		forms = {},
		info = "even " .. require("Module:links").full_link({lang = lang, alt = stem.uvowel}, "term") .. "-stem",
		categories = {},
	}
	
	if stem.gradation then
		data.info = data.info .. ", " ..
			require("Module:links").full_link({lang = lang, alt = stem.gradation.strong.scons}, "term") .. "-" ..
			require("Module:links").full_link({lang = lang, alt = stem.gradation.weak.scons}, "term") .. " gradation"
	else
		data.info = data.info .. ", no gradation"
	end
	
	if not mw.ustring.find(stem.uvowel, "^[aáeioå]$") and mw.title.getCurrentTitle().nsText ~= "Template" then
		error("The final vowel(s) of the stem must be one of a, á, e, i, o, å.")
	end
	
	table.insert(data.categories, lang:getCanonicalName() .. " even " .. fargs[1])
	table.insert(data.categories, lang:getCanonicalName() .. " even " .. (stem.uvowel or "") .. "-stem " .. fargs[1])
	
	if not stem.gradation then
		table.insert(data.categories, lang:getCanonicalName() .. " non-gradating even " .. fargs[1])
	end
	
	data.forms["nom|s"] = {stem:make_form{grade = "strong", variant = args["novowel"] and "none" or nil}}
	data.forms["acc|s"] = {stem:make_form{grade = "weak", ending = "v"}}
	data.forms["gen|s"] = {stem:make_form{grade = "weak"}}
	data.forms["ill|s"] = {stem:make_form{grade = "strong", ending = "j", variant = "e"}}
	data.forms["ine|s"] = {stem:make_form{grade = "weak", ending = "n"}}
	data.forms["ela|s"] = {stem:make_form{grade = "weak", ending = "st"}, stem:make_form{grade = "weak", ending = "s"}}
	data.forms["com|s"] = {stem:make_form{grade = "weak", ending = "jn", variant = "je"}}
	
	data.forms["nom|p"] = {stem:make_form{grade = "weak"}}
	data.forms["acc|p"] = {stem:make_form{grade = "weak", ending = "jt", variant = "j"}}
	data.forms["gen|p"] = {stem:make_form{grade = "weak", ending = "j", variant = "j"}}
	data.forms["ill|p"] = {stem:make_form{grade = "weak", ending = "jda", variant = "j"}}
	data.forms["ine|p"] = {stem:make_form{grade = "weak", ending = "jn", variant = "j"}}
	data.forms["ela|p"] = {stem:make_form{grade = "weak", ending = "jst", variant = "j"}, stem:make_form{grade = "weak", ending = "js", variant = "j"}}
	data.forms["com|p"] = {stem:make_form{grade = "weak", ending = "j", variant = "j"}}
	
	data.forms["ess"] = {stem:make_form{grade = "strong", ending = "n"}}
	
	postprocess(args, data)
	
	return make_table(data)
end


function postprocess(args, data)
	data.n = args["n"]
	
	if args["n"] == "p" then
		table.insert(data.categories, lang:getCanonicalName() .. " pluralia tantum")
	elseif args["n"] == "s" then
		table.insert(data.categories, lang:getCanonicalName() .. " uncountable nouns")
	elseif args["n"] then
		error("args= must be \"s\" or \"p\".")
	end
	
	for key, form in pairs(data.forms) do
		-- Do not show singular or plural forms for nominals that don't have them
		if (args["n"] == "p" and key:find("|s$")) or (args["n"] == "s" and key:find("|p$")) then
			form = nil
		end
		
		data.forms[key] = form
	end
	
	if data.has_attr then
		if not args["attr"][1] then
			data.forms["attr"] = mw.clone(data.forms["nom|s"])
		elseif args["attr"][1] ~= "-" then
			data.forms["attr"] = args["attr"]
		end
	end
	
	data.lemma = (data.forms["nom|" .. (data.n or "s")] or data.forms["acc|" .. (data.n or "s")])[1]
	
	-- Check if the lemma form matches the page name
	if (lang:makeEntryName(data.lemma)) ~= mw.title.getCurrentTitle().text then
		table.insert(data.categories, lang:getCanonicalName() .. " entries with inflection not matching pagename")
	end
end


-- Make the table
function make_table(data)
	local function repl(param)
		local accel = true
		local no_store = false
		
		if param == "info" then
			return mw.getContentLanguage():ucfirst(data.info or "")
		elseif string.sub(param, 1, 1) == "!" then
			no_store = true
			param = string.sub(param, 2)
		elseif string.sub(param, 1, 1) == "#" then
			accel = false
			param = string.sub(param, 2)
		end
		
		local forms = data.forms[param]
		
		if not forms then
			return "—"
		end
		
		local ret = {}
		
		for key, subform in ipairs(forms) do
			table.insert(ret, require("Module:links").full_link({lang = lang, term = subform, accel = accel and {form = param, lemma = data.lemma, no_store = no_store} or nil}))
		end
		
		return table.concat(ret, "<br/>")
	end
	
	local wikicode = {}
	table.insert(wikicode, [=[
{| class="inflection-table vsSwitcher" data-toggle-category="inflection" style="border:solid 1px #CCCCFF; text-align: left;" cellspacing="1" cellpadding="2"
|- style="background: #E2F6E2; text-align: left;"
! class="vsToggleElement" colspan="3" | {{{info}}}]=])

	if data.has_attr then
		table.insert(wikicode, [=[

|- class="vsShow" style="background: #F2F2FF;"
! style="background: #E2F6E2;" | Attributive
| colspan="2" | {{{!attr}}}]=])
	end
	
	table.insert(wikicode, [=[

|- class="vsShow" style="background: #F2F2FF;"
! style="width: 8em; background: #E2F6E2;" | Nominative
| style="width: 15em;" colspan="2" | {{{!nom|]=] .. (data.n or "s") .. [=[}}}
|- class="vsShow" style="background: #F2F2FF;"
! style="background: #E2F6E2;" | Genitive
| colspan="2" | {{{!gen|]=] .. (data.n or "s") .. [=[}}}]=])
	
	if data.has_attr then
		table.insert(wikicode, [=[

|- class="vsHide" style="background: #F2F2FF;"
! style="background: #E2F6E2;" | Attributive
| colspan="2" | {{{attr}}}
]=])
	end
	
	table.insert(wikicode, [=[

|- class="vsHide"
! style="width: 8em; background: #C0E4C0;" |
! style="width: 12em; background: #C0E4C0;" | Singular
! style="width: 12em; background: #C0E4C0;" | Plural
|- class="vsHide" style="background: #F2F2FF;"
! style="background: #E2F6E2;" | Nominative
| data-accel-col="1" | {{{nom|s}}}
| data-accel-col="2" | {{{nom|p}}}
|- class="vsHide" style="background: #F2F2FF;"
! style="background: #E2F6E2;" | Accusative
| data-accel-col="1" | {{{acc|s}}}
| data-accel-col="2" | {{{acc|p}}}
|- class="vsHide" style="background: #F2F2FF;"
! style="background: #E2F6E2;" | Genitive
| data-accel-col="1" | {{{gen|s}}}
| data-accel-col="2" | {{{gen|p}}}
|- class="vsHide" style="background: #F2F2FF;"
! style="background: #E2F6E2;" | Illative
| data-accel-col="1" | {{{ill|s}}}
| data-accel-col="2" | {{{ill|p}}}
|- class="vsHide" style="background: #F2F2FF;"
! style="background: #E2F6E2;" | Inessive
| data-accel-col="1" | {{{ine|s}}}
| data-accel-col="2" | {{{ine|p}}}
|- class="vsHide" style="background: #F2F2FF;"
! style="background: #E2F6E2;" | Elative
| data-accel-col="1" | {{{ela|s}}}
| data-accel-col="2" | {{{ela|p}}}
|- class="vsHide" style="background: #F2F2FF;"
! style="background: #E2F6E2;" | Comitative
| data-accel-col="1" | {{{com|s}}}
| data-accel-col="2" | {{{com|p}}}
|- class="vsHide" style="background: #F2F2FF;"
! style="background: #E2F6E2;" | Essive
| colspan="2" | {{{ess}}}
|}]=])
	
	return mw.ustring.gsub(table.concat(wikicode), "{{{([#!]?[a-z0-9|]+)}}}", repl) .. require("Module:utilities").format_categories(data.categories, lang)
end

return export