Module:BATTD tower changes

---

local p = {}

local function _main(frame)
	-- local functions to improve performance
	local lang = mw.language.new("en")
	local cargo = mw.ext.cargo
	local args = frame.args
	local namespace = mw.title.getCurrentTitle().namespace
	
	local tConcat = table.concat
	local sFormat = string.format
	local sSub = string.sub
	local sUpper = string.upper -- i wonder what's for dinner
	local sGmatch = string.gmatch
	
	-- template parameters
	local version = args["version"]
	local versionCode = args["version code"]
	local versionNote = args["version note"]
	local priority = args["priority"]
	local towerName = args["tower"]
	
	-- get names/links of upgrades
	local upgrades = cargo.query("battd_upgrades", "_pageName, name", {
		where=sFormat("tower='%s' AND NOT unused", towerName)
	})

	-- create name:_pageName dictionary
	local pagenamesByName = {}
	for i, upgrade in ipairs(upgrades) do pagenamesByName[upgrade.name] = upgrade._pageName end
	
	-- helper function for cargo storing
	local function store(priority, names, changes)
		if namespace == 0 or namespace == 3200 then
			frame:callParserFunction("#cargo_store:_table=battd_changes", {
				version     =version,
				version_note=versionNote,
				priority    =priority,
				names       =names,
				changes     =mw.text.killMarkers(changes)
			})
		end
	end
	
	-- helper function for cost change templates
	local function getCostListItem(before, after, liArgs)
		return sFormat("*%s", frame:expandTemplate{title = before > after and "buff" or "nerf", args = liArgs})
	end
	
	local outputTable = {"{|class='wikitable'\n!Upgrades!!Changes"}
	
	for i = 1, 20 do
		local changes		= args[sFormat("changes %i", i)]
		local upgradeNames	= args[sFormat("changes %i upgrades", i)]
		local costBefore	= args[sFormat("changes %i cost before", i)]
		local costAfter		= args[sFormat("changes %i cost after", i)]
		-- stop if this set is missing changes/upgrades
		if changes == "" or (upgradeNames == "" and costBefore == "" and costAfter == "") then break end
		
		local outputRow = {}
		
		for upgradeName in sGmatch(sUpper(upgradeNames), "([^;]+)") do
			outputRow[#outputRow+1] = sFormat("[[%s|%s]]", upgradeName, pagenamesByName[upgradeName])
		end
		
		outputTable[i+1] = sFormat("|-\n|%s||%s", tConcat(outputRow, "\n"), changes)
	end
	
	outputTable[#outputTable+1] = "|}"
	
	return tConcat(outputTable, "\n")
end

function p.main(frame)
	return _main(frame)
end

return p