function gadget:GetInfo()
   return {
      name      = "Weapon Tech Levels",
      desc      = "Makes certain weapons better after technologies are unlocked",
      author    = "Anarchid",
      date      = "28th February 2014",
      license   = "GNU GPL, v2 or later",
      layer     = -1,
      enabled   = true,
   }
end

-- Entire gadget is synced
if not gadgetHandler:IsSyncedCode() then
	return
end

-- list of upgrade class names to tech levels, automatically initialized from weapondef customparam "upgradeClass"
local upgrades = {}

-- table to contain each team's current level in each tech. Ideally should be somehow available to widgets, for example via TeamRulesParams.
-- however, rulesparams cannot have tables, so the table would have to be serialized... cba atm.
local teamUpgradeLevels = {}

function gadget:Initialize()

	-- filter distinct upgrade classes from all weapondef customparams
	for i=1,#WeaponDefs do
		local wd = WeaponDefs[i]
		if wd.customParams then
			local class = wd.customParams.upgradeClass;
			if class then
				if not upgrades[class] then upgrades[class] = true end
			end
		end
	end

	-- assign zero tech level in each tech to each team
	local teams = Spring.GetTeamList()
	for i=1, #teams do
		teamUpgradeLevels[teams[i]] = {}
		for upgrade,_ in pairs(upgrades) do
			teamUpgradeLevels[teams[i]] = 0;
		end
	end
end


-- Currently upgrades are units like any other. This is simply the easiest way to do them.
-- If you want to do it any other way, just call GG.UpgradeComplete on your appropriate event.
function gadget:UnitCreated(unitID, unitDefID, teamID, builderID)
	local ud = UnitDefs[unitDefID];
	if ud.customParams then
		local tech = ud.customParams.upgradeTech;
		local level = tonumber(ud.customParams.upgradeLevel);
		if tech and level then
			GG.UpgradeComplete(tech, level, teamID);
		end
	end
end

function GG.UpgradeComplete(techName, level, teamID)
	level = math.max(teamUpgradeLevels[teamID][techName], level);
	teamUpgradeLevels[teamID][techName] = level;
end

function gadget:UnitPreDamaged(unitID, unitDefID, unitTeam, damage, paralyzer, weaponDefID, attackerID, attackerDefID, attackerTeam)
	local wd = WeaponDefs[weaponDefID];
	local weaponTech = wd.customParams.upgradeClass or false;

	if (weaponTech) then
		local techModifier = (teamUpgradeLevels[attackerTeam][weaponTech] or 0);
		Spring.Echo ("Techmodifier:" .. techModifier)
		damage = damage + damage*techModifier;
		paralyzer = paralyzer + paralyzer*techModifier;
		Spring.Echo ("Damage:" .. damage)
	end

	return damage;
end