--[[ Copyright (c) 2019 robot256 (MIT License)

* Project: Multiple Unit Train Control

* File: checkModuleMatching.lua

* Description: Checks if a pair of locos are RET modular type, and if the module configurations match.

* Returns true if they are not modular locos.

--]]

local moduleTypes = nil

local function isRelevantModule(name)

if moduleTypes == nil then

moduleTypes = {}

game.print("MUTC is Caching RET module types")

-- Cache table of allowable modules

if prototypes.technology["ret-modular-locomotives"] then

for _,effect in pairs(prototypes.technology["ret-modular-locomotives"].effects) do

if effect.type == "unlock-recipe" and prototypes.equipment[effect.recipe] then

moduleTypes[effect.recipe] = true

--game.print("Cached module type " .. effect.recipe)

end

end

end

end

if moduleTypes[name] then

return true

else

return false

end

end

function checkModuleMatching(loco1, loco2)

-- Given a pair of locos that have same type and are in the right spot in the train to be a pair

-- Check if they have modular locomotive grids

if loco1.grid and loco1.grid.prototype.name=="modular-locomotive-grid" then

-- Read grid contents of both locos

local gridOne = loco1.grid.get_contents()

local gridTwo = loco2.grid.get_contents()

local matched = true

for k,v in pairs(gridOne) do

if isRelevantModule(k) and not(gridTwo[k] and gridTwo[k]==v) then

matched = false

break

end

end

if matched then

for k,v in pairs(gridTwo) do

if isRelevantModule(k) and not(gridOne[k] and gridOne[k]==v) then

matched = false

break

end

end

end

return matched

else

-- Not a modular locomotive, always able to replace

return true

end

end

return checkModuleMatching