local neural  = require('neural.interface')
local Sound   = require('sound')
local Util    = require('util')

local os     = _G.os

local WALK_SPEED = 1.5
local MAX_COWS   = 12

neural.assertModules({
  'plethora:sensor',
  'plethora:scanner',
  'plethora:laser',
  'plethora:kinetic',
  'plethora:introspection',
})

local fed = { }

local function resupply()
  local slot = neural.getEquipment().list()[1]
  if slot and slot.count > 32 then
    return
  end
  print('resupplying')
  for _ = 1, 2 do
    local dispenser = Util.find(neural.scan(), 'name', 'minecraft:dispenser')
    if not dispenser then
      print('dispenser not found')
      break
    end
    if math.abs(dispenser.x) <= 1 and math.abs(dispenser.z) <= 1 then
      neural.lookAt(dispenser)
      for _ = 1, 8 do
        neural.use(0, 'off')
        os.sleep(.2)
        neural.getEquipment().suck(1, 64)
      end
      break
    else
      neural.walkTo({ x = dispenser.x, y = 0, z = dispenser.z }, WALK_SPEED)
    end
  end
end

local function breed(entity)
  print('breeding')
  entity.lastFed = os.clock()
  fed[entity.id] = entity

  neural.walkAgainst(entity, 1, WALK_SPEED)
  entity = neural.getMetaByID(entity.id)
  if entity then
    neural.lookAt(entity)
    neural.use(1)
    os.sleep(.1)
  end
end

local function kill(entity)
  print('killing')
  neural.walkAgainst(entity, 2.5, WALK_SPEED)
  entity = neural.getMetaByID(entity.id)
  if entity then
    neural.lookAt(entity)
    neural.fireAt({ x = entity.x, y = 0, z = entity.z })
    Sound.play('entity.firework.launch')
    os.sleep(.2)
  end
end

local function getEntities()
  return Util.filter(neural.sense(), function(entity)
    if entity.name == 'Cow' and entity.y > -.5 then
      return true
    end
  end)
end

local function getHungry(entities)
  for _,v in pairs(entities) do
    if not fed[v.id] or os.clock() - fed[v.id].lastFed > 60 then
      return v
    end
  end
end

local function randomEntity(entities)
  local r = math.random(1, Util.size(entities))
  local i = 1
  for _, v in pairs(entities) do
    i = i + 1
    if i > r then
      return v
    end
  end
end

while true do
  resupply()

  local entities = getEntities()

  if Util.size(entities) > MAX_COWS then
    kill(randomEntity(entities))
  else
    local entity = getHungry(entities)
    if entity then
      breed(entity)
    else
      os.sleep(5)
    end
  end
end