--[[
authors: jakedacatman and kepler155c

pastebin run uzghlbnc
package install core
package install milo
reboot

Use multiple brewing stands at once to brew potions.
SETUP:
  Place an introspection module into the turtles inventory.
  Connect turtle to milo network with a wired modem.
  Connect turtle to a second wired modem that is connected to brewing stands ONLY.
  Add as many brewing stands as needed.
CONFIGURATION:
  Set turtle as a "Generic Inventory"
  export blaze powder to slot 5
  import from slots 7-9
Use this turtle for machine crafting.
--]]

local Event      = require('event')
local Peripheral = require('peripheral')
local Util       = require('util')

local device     = _G.device
local fs         = _G.fs
local os         = _G.os
local turtle     = _G.turtle

local STARTUP_FILE = 'usr/autorun/brewArray.lua'

local function equip(side, item, rawName)
  local equipped = Peripheral.lookup('side/' .. side)

  if equipped and equipped.type == item then
    return true
  end

  if not turtle.equip(side, rawName or item) then
    if not turtle.selectSlotWithQuantity(0) then
      error('No slots available')
    end
    turtle.equip(side)
    if not turtle.equip(side, item) then
      error('Unable to equip ' .. item)
    end
  end

  turtle.select(1)
end

equip('left', 'plethora:introspection', 'plethora:module:0')
local intro = device['plethora:introspection']
local inv = intro.getInventory()

if not fs.exists(STARTUP_FILE) then
  Util.writeFile(STARTUP_FILE,
    [[os.sleep(1)
shell.openForegroundTab('packages/milo/apps/brewArray.lua')]])
end

local brew
local localName

print('detecting wired modem connected to brewing stands...')
for _, dev in pairs(device) do
  if dev.type == 'wired_modem' then
    local list = dev.getNamesRemote()
    brew = { }
    localName = dev.getNameLocal()
    for _, name in pairs(list) do
      if device[name].type ~= 'minecraft:brewing_stand' then
        brew = nil
        break
      end
      table.insert(brew, device[name])
    end
  end
  if brew then
    print('Using wired modem: '  .. dev.name)
    print('Brewing stands: ' .. #brew)
    break
  end
end

if not brew then
  error('Turtle must be connected to a second wired_modem connected to brewing stands only')
end

_G.printError([[Program must be restarted if new brewing stands are added.]])

-- slots 1-3: bottles
-- slot 4: ingredient
-- slot 5: blaze powder

local function process(list)
  local active = false

  for _, brewing in ipairs(Util.shallowCopy(brew)) do
    local s, m = pcall(function()-- block updates can cause errors
      local bs = brewing.list()

      local cooking = bs[1] and bs[2] and bs[3] and bs[4]
      if cooking then
        active = true
      end

      -- fuel
      local fuel = bs[5] or { count = 0 }
      if fuel.count < 1 then
        print('fueling ' ..brewing.name)
        brewing.pullItems(localName, 5, 1, 5)
      end

      if not cooking and (bs[1] or bs[2] or bs[3] or bs[4]) then
        print('pulling from : ' .. brewing.name)
        for i = 1, 4 do
          brewing.pushItems(localName, i, 1, 6 + i)
        end
      end

      if not cooking and list[1] and list[2] and list[3] and list[4] then
        print('brewing : ' .. brewing.name)
        for i = 1, 4 do
          brewing.pullItems(localName, i, 1, i)
          list[i].count = list[i].count - 1
          if list[i].count == 0 then
            list[i] = nil
          end
        end

        -- push brewing stand to end of list
        Util.removeByValue(brew, brewing)
        table.insert(brew, brewing)
      end
    end)
    if not s and m then
      _G.printError(m)
    end
  end

  return active
end

Event.on('turtle_inventory', function()
  while true do
    if not process(inv.list()) then
      break
    end
    os.sleep(3)
  end
end)

Event.onInterval(5, function()
  -- for some reason, it keeps stalling ...
  os.queueEvent('turtle_inventory')
end)

os.queueEvent('turtle_inventory')
Event.pullEvents()