-- sequence_feeder.lua
-- Feed items into a GregTech input bus in STRICT order, one step at a time,
-- using ComputerCraft (CC:Tweaked). Each step is pushed only after the
-- previous one has been consumed by the machine.
--
-- Wiring: put a wired modem on the GT input bus AND on the buffer chest/barrel,
-- connect them (and a modem on this computer) with networking cable.
-- Run `peripheral.getNames()` in the Lua prompt to find the exact names,
-- then fill them in below.

--========================= CONFIG =========================--
local BUFFER       = "minecraft:barrel_0"  -- inventory holding items to feed
local MACHINE      = "gtceu:hv_input_bus_0"   -- the GT input bus to feed into
local MACHINE_SLOT = 1                       -- which bus slot to feed
local OUTPUT       = "ae2:interface_0"  -- where leftover items go when done
local POLL         = 0.5                     -- seconds between checks
local TIMEOUT      = 0                        -- max seconds to wait per step (0 = wait forever)
local NAG          = 15                       -- print a "still waiting" note every N seconds

local OUTPUT_ITEMS = {
  ["kubejs:cyan_prismatic_core"] = true,
  ["kubejs:active_prismatic_core"] = true,
}

local SEQUENCE = {
{ name = "kubejs:inert_prismatic_core", count = 1 },
{ name = "kubejs:chromatic_stabilizer", count = 1 },
{ name = "kubejs:red_prismatic_core", count = 1 },
{ name = "kubejs:inert_prismatic_core", count = 1 },
{ name = "kubejs:yellow_prismatic_core", count = 1 },
{ name = "kubejs:chromatic_stabilizer", count = 1 },
{ name = "kubejs:green_prismatic_core", count = 1 },
{ name = "kubejs:yellow_prismatic_core", count = 1 },
{ name = "kubejs:cyan_prismatic_core", count = 1 },
{ name = "kubejs:chromatic_stabilizer", count = 1 },
{ name = "kubejs:blue_prismatic_core", count = 1 },
{ name = "kubejs:chromatic_stabilizer", count = 1 },
{ name = "kubejs:green_prismatic_core", count = 1 },
{ name = "kubejs:chromatic_stabilizer", count = 1 },
{ name = "kubejs:red_prismatic_core", count = 1 },
}

--==========================================================--

local buffer  = peripheral.wrap(BUFFER)  or error("No inventory named " .. BUFFER)
local machine = peripheral.wrap(MACHINE) or error("No inventory named " .. MACHINE)
local output  = peripheral.wrap(OUTPUT)  or error("No inventory named " .. OUTPUT)

-- Find first buffer slot containing `name`.
local function findSlot(inv, name)
  for slot, item in pairs(inv.list()) do
    if item.name == name then return slot end
  end
  return nil
end

-- True when the target bus slot is empty (previous item consumed).
local function slotEmpty()
  return machine.list()[MACHINE_SLOT] == nil
end

-- Block until `cond()` is true. Waits forever if TIMEOUT == 0.
-- Prints `msg` every NAG seconds so you can see what it's stuck on.
local function waitFor(cond, msg)
  local waited = 0
  while not cond() do
    sleep(POLL)
    waited = waited + POLL
    if NAG > 0 and waited % NAG < POLL then
      print("  ...waiting: " .. msg)
    end
    if TIMEOUT > 0 and waited >= TIMEOUT then
      error("Timed out: " .. msg)
    end
  end
end

for i, step in ipairs(SEQUENCE) do
  print(("Step %d/%d: %s x%d"):format(i, #SEQUENCE, step.name, step.count))

  -- make sure the slot is clear before pushing
  waitFor(slotEmpty, "slot " .. MACHINE_SLOT .. " to clear")

  local remaining = step.count
  while remaining > 0 do
    local src = findSlot(buffer, step.name)
    if not src then
      -- not in the buffer yet (e.g. an intermediate still being produced); wait
      waitFor(function() return findSlot(buffer, step.name) ~= nil end,
              step.name .. " to appear in buffer")
    else
      local moved = buffer.pushItems(MACHINE, src, remaining, MACHINE_SLOT)
      if moved == 0 then
        sleep(POLL)  -- slot busy/full; wait for the machine to pull, then retry
      else
        remaining = remaining - moved
      end
    end
  end

  waitFor(slotEmpty, step.name .. " to be consumed")  -- wait for the machine to eat it
end

print("Sequence complete. Moving selected items to output...")

-- Move only whitelisted items from the buffer to the output peripheral.
local drained = 0
for slot, item in pairs(buffer.list()) do
  if OUTPUT_ITEMS[item.name] then
    drained = drained + buffer.pushItems(OUTPUT, slot)
  end
end
print(("Moved %d item(s) to %s."):format(drained, OUTPUT))