Module:Section link

Documentation for this module may be created at Module:Section link/doc

-- This module implements {{section link}}.

local checkType = require('libraryUtil').checkType

local p = {}

local function makeWikitextError(msg)
	return string.format(
		'<strong class="error">[[Template:Section link]] error: %s.</strong>',
		msg
	)
end

local function makeSectionLink(page, section, display)
	display = display or section
	page = page or ''
	return string.format('[[%s#%s|%s]]', page, section, display)
end

function p._main(page, sections, options, title)
	-- Validate input.
	checkType('_main', 1, page, 'string', true)
	checkType('_main', 3, options, 'table', true)
	if type(sections) == 'string' then
		sections = {sections}
	elseif type(sections) ~= 'table' then
		error(string.format(
			"type error in argument #2 to '_main' (string or table expected, got %s)",
			type(sections)
		), 2)
	end
	options = options or {}
	title = title or mw.title.getCurrentTitle()
	if #sections < 1 then
		return makeWikitextError('at least one section must be specified')
	end

	-- Make the link(s).
	local isShowingPage = not options.nopage
	if #sections == 1 then
		local linkPage = page or ''
		local section = sections[1] or 'Notes'
		local display = '§&thinsp;' .. section
		if isShowingPage then
			page = page or title.prefixedText
			display = page .. ' ' .. display
		end
		return makeSectionLink(linkPage, section, display)
	else
		-- Multiple sections. First, make the list of links.
		local ret = {}
		for i, section in ipairs(sections) do
			ret[i] = makeSectionLink(page, section)
		end
		
		-- Assemble the list of links into a string with mw.text.listToText.
		-- We use the default arguments for mw.text.listToText, unless we have
		-- exactly two sections, in which case we use a custom conjunction.
		local conjunction
		if #sections == 2 then
			conjunction = '&#8203; and '
		end
		ret = mw.text.listToText(ret, nil, conjunction)

		-- Add the intro text.
		local intro = '§§&thinsp;'
		if isShowingPage then
			intro = (page or title.prefixedText) .. ' ' .. intro
		end
		ret = intro .. ret
		
		return ret
	end
end

function p.main(frame)
	local args = require('Module:Arguments').getArgs(frame, {
		wrappers = 'Template:Section link'
	})

	-- Sort the arguments.
	local page
	local sections, options = {}, {}
	for k, v in pairs(args) do
		if k == 1 then
			-- Doing this in the loop because of a bug in [[Module:Arguments]]
			-- when using pairs with deleted arguments.
			page = v
		elseif type(k) == 'number' then
			sections[k] = v
		else
			options[k] = v
		end
	end

	-- Compress the sections array.
	local function compressArray(t)
		local nums, ret = {}, {}
		for num in pairs(t) do
			nums[#nums + 1] = num
		end
		table.sort(nums)
		for i, num in ipairs(nums) do
			ret[i] = t[num]
		end
		return ret
	end
	sections = compressArray(sections)
	
	return p._main(page, sections, options)
end

return p