drone.lua

local drone = component.proxy(component.list("drone")())
local ic = component.proxy(component.list("inventory_controller")())
local maxSlot = drone.inventorySize()
local valid_sides = {0, 1, 2, 3, 4, 5}

function getItemName(slot)
    local item = ic.getStackInInternalSlot(slot)
    if item then
        return item.name
    else
        return ''
    end
end

function isItem(slot, name)
    return getItemName(slot) == name
end

function getSideItemName(side, slot)
    local item = ic.getStackInSlot(side, slot)
    if item then
        return item.name
    else
        return ''
    end
end

function isSideItem(side, slot, name)
    return getSideItemName(side, slot) == name
end

function findSideItem(side, itemName)
    local max = ic.getInventorySize(side)
    if max then
        for slot = 1, max, 1 do
            if isSideItem(side, slot, itemName) then
                return slot
            end
        end
    end
    return 0
end

function findItemOnSides(itemName)
    for k, side in pairs(valid_sides) do
        local slot = findSideItem(side, itemName)
        if slot > 0 then
            return suckFromSlot(side, slot)
        end
    end
    return 0
end

function suckFromSlot(side, slot)
    local newSlot = findEmptySlot()
    if newSlot == 0 then
        newSlot = cleanASlot()
    end

    if newSlot > 0 then
        drone.select(newSlot)
        ic.suckFromSlot(side, slot)
        insertSideEmptySlots(side, slot)
        return newSlot
    end
    return 0
end


function dropIntoSlot(slot)
    drone.select(slot)
    local name = getItemName(slot)
    local side, newSlot = findEmptySlotOnSides()
    if newSlot > 0 then
        ic.dropIntoSlot(side, newSlot)
        insertSideItems(side, newSlot, name)
        return true
    end
    return false
end

function findItem(itemName, slot)
    for slot = slot, maxSlot, 1 do
        if isItem(slot, itemName) then
            return slot
        end
    end
    return 0
end

function findEmptySlot()
    for slot = 1, maxSlot, 1 do
        if isEmptySlot(slot) then
            return slot
        end
    end
    return 0
end

function isEmptySlot(slot)
    local count = drone.count(slot)
    if count == 0 then
        return true
    else
        return false
    end
end

function findEmptySideSlot(side)
    local max = ic.getInventorySize(side)
    if max then
        for slot = 1, max, 1 do
            if isEmptySideSlot(side, slot) then
                return slot
            end
        end
    end
    return 0
end

function isEmptySideSlot(side, slot)
    return ic.getSlotStackSize(side, slot) == 0
end

function isFullSideSlot(side, slot)
    return ic.getSlotStackSize(side, slot) == 64
end

function findEmptySlotOnSides()
    for k, side in pairs(valid_sides) do
        local slot = findEmptySideSlot(side)
        if slot > 0 then
            return side, slot
        end
    end
    return 0, 0
end

function cleanASlot()
    for slot = 1, maxSlot, 1 do
        if isFullSlot(slot) then
            if dropIntoSlot(slot) then
                return slot
            end
            break
        end
    end
    return 0
end

function isFullSlot(slot)
    local count = drone.count(slot)
    if count == 64 then
        return true
    else
        return false
    end
end

drone.setStatusText(drone.name())
local itemName
local ret

while true do
    computer.pullSignal(0.5)
    itemName = getItemName(1)
    ret = findItemOnSides(itemName)
    drone.setStatusText(tostring(ret))
end