Module:Sandbox/Szqecs/Adjacent stations

-- -- This module implements --

local p = {}

local args = {} local origArgs local root local data = {}

local function union(t1, t2, t3, t4) -- Returns the union of the values of four tables, as a sequence. local vals = {} for k, v in pairs(t1) do		vals[v] = true end for k, v in pairs(t2) do		vals[v] = true end for k, v in pairs(t3) do		vals[v] = true end for k, v in pairs(t4) do		vals[v] = true end local ret = {} for k, v in pairs(vals) do		table.insert(ret, k)	end return ret end

local function getArgNums(prefix) -- Returns a table containing the numbers of the arguments that exist -- for the specified prefix. For example, if the prefix was 'data', and -- 'line1', 'line2', and 'line5' exist, it would return {1, 2, 5}. local nums = {} for k, v in pairs(args) do local num = tostring(k):match('^' .. prefix .. '([1-9]%d*)$') if num then table.insert(nums, tonumber(num)) end end table.sort(nums) return nums end

local function addRow(rowArgs) -- Adds a row to the infobox, with either a header cell -- or a label/data cell combination. end

local function renderHeader root :tag('tr') :tag('th') :addClass('hcA') :wikitext('Previous station') :tag('th') :attr('colspan', 3) :addClass('hmA') :wikitext('Title') :tag('th') :addClass('hcA') :wikitext('Following station') end

local function renderRows -- Gets the union of the header, line, type and note-row argument numbers, -- and renders them all in order using addRow. local rownums = union(getArgNums('header'), getArgNums('line'), getArgNums('type'), getArgNums('note-row')) table.sort(rownums) for i, num in ipairs(rownums) do local typeName = args['type' .. tostring(num)] or args['line' .. tostring(num)] local data if typeName and ((args['system'] .. tostring(num)) or (arg['system'] .. tostring(rownums[i - 1]))) then end addRow({

})	end end

local function _main -- Specify the overall layout of the succession box, with special settings root = mw.html.create('table') root:addClass('wikitable adjacent-stations') renderHeader renderRows return tostring(root) end

local function preprocessSingleArg(argName) -- If the argument exists and isn't blank, add it to the argument table. -- Blank arguments are treated as nil to match the behaviour of ParserFunctions. if not args[argName] and origArgs[argName] and origArgs[argName] ~= '' then args[argName] = origArgs[argName] end end

local function preprocessArgs(prefixTable, step) -- Assign the parameters with the given prefixes to the args table, in order, in batches -- of the step size specified. This is to prevent references etc. from appearing in the -- wrong order. The prefixTable should be an array containing tables, each of which has -- two possible fields, a "prefix" string and a "depend" table. The function always parses -- parameters containing the "prefix" string, but only parses parameters in the "depend" -- table if the prefix parameter is present and non-blank. if type(prefixTable) ~= 'table' then error("Non-table value detected for the prefix table", 2) end if type(step) ~= 'number' then error("Invalid step value detected", 2) end -- Get arguments without a number suffix, and check for bad input. for i, v in ipairs(prefixTable) do		if type(v) ~= 'table' or type(v.prefix) ~= "string" or (v.depend and type(v.depend) ~= 'table') then error('Invalid input detected to preprocessArgs prefix table', 2) end preprocessSingleArg(v.prefix) -- Only parse the depend parameter if the prefix parameter is present and not blank. if args[v.prefix] and v.depend then for j, dependValue in ipairs(v.depend) do				if type(dependValue) ~= 'string' then error('Invalid "depend" parameter value detected in preprocessArgs') end preprocessSingleArg(dependValue) end end end

-- Get arguments with number suffixes. local a = 1 -- Counter variable. local moreArgumentsExist = true while moreArgumentsExist == true do		moreArgumentsExist = false for i = a, a + step - 1 do			for j, v in ipairs(prefixTable) do local prefixArgName = v.prefix .. tostring(i) if origArgs[prefixArgName] then moreArgumentsExist = true -- Do another loop if any arguments are found, even blank ones. preprocessSingleArg(prefixArgName) end -- Process the depend table if the prefix argument is present and not blank, or				-- we are processing "prefix1" and "prefix" is present and not blank, and -- if the depend table is present. if v.depend and (args[prefixArgName] or (i == 1 and args[v.prefix])) then for j, dependValue in ipairs(v.depend) do local dependArgName = dependValue .. tostring(i) preprocessSingleArg(dependArgName) end end end end a = a + step end end function p.main(frame) -- If called via #invoke, use the args passed into the invoking template. -- Otherwise, for testing purposes, assume args are being passed directly in. if frame == mw.getCurrentFrame then origArgs = frame:getParent.args else origArgs = frame end local dependants = { 'left', 'right', 'to-left', 'to-right', 'to', 'transfer', 'oneway-left', 'oneway-right', 'non-stop', 'through', 'through-left', 'through-right', 'reverse', 'reverse-left', 'reverse-right' }	preprocessArgs({		{prefix = 'system'},		{prefix = 'line', depend = dependants},		{prefix = 'type', depend = dependants}	}) return _main end return p