local rocket_drawer = peripheral.wrap("functionalstorage:oak_4_0")
local warhead_drawer = peripheral.wrap("functionalstorage:oak_4_1")
local controller = peripheral.find("mekmissiles:missile_silo")
local message_display = peripheral.wrap("monitor_1")

local rocket_relay = peripheral.wrap("redstone_relay_5")

local small_warhead_relay = peripheral.wrap("redstone_relay_7")
local medium_warhead_relay = peripheral.wrap("redstone_relay_6")
local large_warhead_relay = peripheral.wrap("redstone_relay_9")
local huge_warhead_relay = peripheral.wrap("redstone_relay_8")

local engine_item = "mekmissiles:rocket_engine"
local body_item = "mekmissiles:rocket_body"
local nose_item = "mekmissiles:rocket_nose_cone"

local small_warhead = "mnwe:industrial_bomb"
local medium_warhead = "mnwe:nuclear_bomb"
local large_warhead = "mnwe:hydrogen_bomb"
local huge_warhead = "mnwe:antimatter_bomb"

function display_message(message, wait)
    if message_display then
        message_display.clear()
        message_display.setCursorPos(1, 1)
        message_display.write(message)
    else
        print("W: No message display found")
        print(message)
    end
    if wait then
        message_display.setCursorPos(1, 2)
        message_display.write("Press any button to continue...")
        os.pullEvent("redstone")
        os.sleep(1.1)
    end
end

if not rocket_drawer then
    display_message("No rocket parts storage drawer found")
    return
end

if not warhead_drawer then
    display_message("No warhead storage drawer found")
    return
end

if not controller then
    display_message("No missile silo controller found")
    return
end

::begin::

controller.pushItems(peripheral.getName(warhead_drawer), 4)
controller.pushItems(peripheral.getName(rocket_drawer), 3)
controller.pushItems(peripheral.getName(rocket_drawer), 2)
controller.pushItems(peripheral.getName(rocket_drawer), 1)

-- Wait for redstone signal to start assembly
display_message("Rocket assembly system ready.")
os.pullEvent("redstone")
local relay_states = {
    rocket_relay.getInput("back"),
    small_warhead_relay.getInput("back"),
    medium_warhead_relay.getInput("back"),
    large_warhead_relay.getInput("back"),
    huge_warhead_relay.getInput("back")
}

if relay_states[2] or relay_states[3] or relay_states[4] or relay_states[5] then
    display_message("Please assemble the rocket first, then select the warhead type.")
    goto begin
end

local engine_slot = nil
local body_slot = nil
local nose_slot = nil

local small_warhead_slot = nil
local medium_warhead_slot = nil
local large_warhead_slot = nil
local huge_warhead_slot = nil

for i = 1, rocket_drawer.size() do
    local item = rocket_drawer.getItemDetail(i)
    if item then
        if item.name == engine_item then
            engine_slot = i
        elseif item.name == body_item then
            body_slot = i
        elseif item.name == nose_item then
            nose_slot = i
        end
    end
end

for i = 1, warhead_drawer.size() do
    local item = warhead_drawer.getItemDetail(i)
    if item then
        if item.name == small_warhead then
            small_warhead_slot = i
        elseif item.name == medium_warhead then
            medium_warhead_slot = i
        elseif item.name == large_warhead then
            large_warhead_slot = i
        elseif item.name == huge_warhead then
            huge_warhead_slot = i
        end
    end
end

if not engine_slot then
    display_message("No rocket engine found in drawer", true)
    goto begin
end

if not body_slot then
    display_message("No rocket body found in drawer", true)
    goto begin
end

if not nose_slot then
    display_message("No rocket nose cone found in drawer", true)
    goto begin
end

rocket_drawer.pushItems(peripheral.getName(controller), engine_slot, 1)
rocket_drawer.pushItems(peripheral.getName(controller), body_slot, 1)
rocket_drawer.pushItems(peripheral.getName(controller), nose_slot, 1)

::warhead_selection::
os.sleep(1.1)
if not small_warhead_slot and not medium_warhead_slot and not large_warhead_slot and not huge_warhead_slot then
    display_message("No warheads found in drawer", true)
    goto begin
end

display_message("Rocket assembled, please select the warhead type.")

os.pullEvent("redstone")
relay_states = {
    rocket_relay.getInput("back"),
    small_warhead_relay.getInput("back"),
    medium_warhead_relay.getInput("back"),
    large_warhead_relay.getInput("back"),
    huge_warhead_relay.getInput("back")
}
os.sleep(1.1)

if relay_states[1] then
    display_message("Rocket already assembled, please select warhead.", true)
    goto warhead_selection
end

local true_count = 0
for i = 2, 5 do
    if relay_states[i] then
        true_count = true_count + 1
    end
end

if true_count > 1 then
    display_message("Please select only one warhead type.")
    goto warhead_selection
end

local selected_warhead_slot = nil
if relay_states[2] then
    selected_warhead_slot = small_warhead_slot
elseif relay_states[3] then
    selected_warhead_slot = medium_warhead_slot
elseif relay_states[4] then
    selected_warhead_slot = large_warhead_slot
elseif relay_states[5] then
    selected_warhead_slot = huge_warhead_slot
end

if not selected_warhead_slot then
    print(textutils.serialize(relay_states))
    display_message("Selected warhead not found in drawer", true)
    goto warhead_selection
end

warhead_drawer.pushItems(peripheral.getName(controller), selected_warhead_slot, 1)
display_message("Warhead loaded into rocket.", true)

goto begin