Module:Sandbox/KleptomaniacViolet/Language families/Autotree

local p = {}

function get_node (title)
	local title_data = mw.loadData("Module:Sandbox/KleptomaniacViolet/Language families/Data")
	local result = nil
	for n, page in pairs(title_data) do
		tab = mw.loadData(page).language_nodes
		if tab[title] ~= nil then
			result = tab[title]
		end
	end
	return result
end

function get_first_node_data (target_node_title, fallback_node_title, page_title, errors)	
	if fallback_node_title ~= "" and page_title == target_node_title then
		table.insert(errors, "redundant fallback")
	end
	
	if page_title ~= target_node_title then
		table.insert(errors, "node title mismatch")
	end

	local node_data = get_node(target_node_title)
	if node_data == nil then
		if fallback_node_title ~= "" then
			node_data = get_node(fallback_node_title)
		end
		if node_data == nil then
			table.insert(errors, "no node data")
		else
			table.insert(errors, "using fallback")
		end
	end
	return node_data
end

function show_errors (frame, errors)
	local res = ""
	for i, err in ipairs(errors) do
		res = res .. "<br>" .. frame:expandTemplate{ title = "User:KleptomaniacViolet/Language family errors/" .. err, args = {} }
	end
	return res
end

function p.gen_tree (frame)
	local errors = {}
	
	local target_node_title = frame.args["targetnode"]
	local expected_parent_article = frame.args["expectedparentarticle"]
	if expected_parent_article == "" then
		expected_parent_article = nil
	end
	local fallback_node_title = frame.args["fallbacknode"]
	local page_title = frame.args["pagetitle"]
	
	local node_data = get_first_node_data(target_node_title, fallback_node_title, page_title, errors)
	local nodes = {}

	local count = 0
	while node_data ~= nil do
		display = node_data['display']
		link = node_data['link']
		if link ~= nil then
			wikitext = '[[' .. link .. '|' .. mw.text.nowiki(display) .. ']]'
		else
			wikitext = mw.text.nowiki(display)
		end
		
		table.insert(nodes, 1, wikitext)
		
		target_node_title = node_data['parent']
		if target_node_title == nil then
			node_data = nil
		elseif count > 30 then
			node_data = nil
			table.insert(errors, "tree too deep")
		else
			count = count + 1
			node_data = get_node(target_node_title)
			if expected_parent_article ~= nil then
				if node_data == nil then
					table.insert(errors, "no parent found but one was expected")
				elseif node_data['link'] ~= nil then
					if node_data['title'] ~= expected_parent_article then
						table.insert(errors, "expected parent mistmatch")
					end
					expected_parent_article = nil
				end
			end
		end
	end
	
	local result = ""
	for n, text in ipairs(nodes) do
		result = result .. '<ul style="line-height:100%; margin-left:5px;padding-left:0"><li>'
		if n == #nodes then
			result = result .. "'''" .. text .. "'''"
		else
			result = result .. text
		end
		result = result .. "\n"
	end
	for n = 1, #nodes do
		result = result .. "</ul>"
	end
	
	return result .. "\n" .. show_errors(frame, errors)
end

function p.gen_children (frame)
	local errors = {}
	
	local target_node_title = frame.args["targetnode"]
	local fallback_node_title = frame.args["fallbacknode"]
	local page_title = frame.args["pagetitle"]
	
	local node_data = get_first_node_data(target_node_title, fallback_node_title, page_title, errors)

	local child_titles = {}
	
	if node_data ~= nil then
		child_titles = node_data['children']
	end
	
	local children = {}
	for n, child_title in ipairs(child_titles) do
		node_data = get_node(child_title)
		if node_data ~= nil then
			display = node_data['display']
			link = node_data['link']
			if link ~= nil then
				wikitext = '[[' .. link .. '|' .. mw.text.nowiki(display) .. ']]'
			else
				wikitext = mw.text.nowiki(display)
			end
			table.insert(children, 1, wikitext)
		end
	end
	
	local result = ""
	for n, text in ipairs(children) do
		result = result .. "* " .. text .. "\n"
	end
	return result .. "\n" .. show_errors(frame, errors)
end

function p.get_parent_article (frame)
	local target_node_title = frame.args[1]
	local node_data = get_node(target_node_title)
	local res = nil
	local count = 0
	while node_data ~= nil and res == nil and count < 30 do
		count = count + 1
		if node_data['link'] ~= nil then
			res = node_data['title']
		end
		if node_data['parent'] == nil then
			node_data = nil
		else
			node_data = get_node(node_data['parent'])
		end
	end
	if res == nil then
		res = ""
	end
	return res
end

return p