OC Mob Duplicator

local component = require("component")
local sides = require("sides")
local term = require("term")

local transposer = component.transposer
local gpu = component.gpu

local mobCount = 2
local chestSide = sides.down
local duplicatorSide = sides.up

local mobList = {
    witherSkeleton = 1,
    ghast = 2,
}

local abbr = {
    witherSkeleton = {"witherSkeleton", "ws", "wither skeleton"},
    ghast = {"ghast", "gh"},
}

function init()
    gpu.setResolution(60, 20)
end

function findEmpty()
    for i = 1, mobCount do
        if (transposer.getSlotStackSize(chestSide, i) == 0) then
            return i
        end
    end
end

function returnPokeball()
    transposer.transferItem(duplicatorSide, chestSide, 1, 7, findEmpty())
    print("Retrieving Mob...")
    os.sleep(1/2)
end

function sendPokeball(mob)
    returnPokeball()
    transposer.transferItem(chestSide, duplicatorSide, 1, mobList[mob], 7)
    print("Sending Mob...")
    os.sleep(1/2)
end

function readInput(input)
    if (input == "stop" or input == "STOP") then
        return "stop"
    end
    for k,v in pairs(abbr) do
        for _,n in ipairs(v) do
            if (n == input) then
                return v[1]
            end
        end
    end
end

init()
while true do
    term.clear()

    print("Avaliable Mobs: ")

    for k, v in pairs(abbr) do
        io.write("\t"..v[1].." (")
        for i,n in ipairs(v) do
            if (i ~= #v) then
                io.write(n..", ")
            else
                io.write(n)
            end
        end
        io.write(")\n")
    end

    local mobName = nil
    repeat
        print("Enter a mob (stop to stop): ")
        input = readInput(io.read())
    until(input ~= nil)
    if (input == "stop") then
        returnPokeball()
        print("Process stopped.")
    else
        sendPokeball(input)
    end

    os.sleep(1)
end