extmineapi 0.2

-- digging forward while detecting blocks
function tryDigForward()
  logger.trace("trying dig forward...")
  if turtle.dig() then
    logger.debug("dig forward");
  end
end

-- digging up while detected blocks
function tryDigUp()
  logger.trace("trying dig up...")
  if turtle.digUp() then
    logger.debug("dig up");
  end
end

-- attacking while mob detected.
function tryAttack()
  logger.trace("trying attack...")
  while turtle.attack() do
    logger.debug("attacking!")
  end
end

-- just dig gown if it isn't a chest
function tryDigDown()
  logger.trace("trying dig down...")
  turtle.select(14)
  if not turtle.compareDown() then
    if turtle.digDown() then
      logger.debug("dig down")
    end
  end
end

-- placing torch in the left wall.
-- returns false if torches is out.
-- required slot 15.
function tryPlaceTorch()
  logger.debug("trying place torch")
  if turtle.getItemCount(15) < 1 then
    logger.info("torches is out!")
    return false
  end
  turtle.turnRight()
  turtle.select(15)
  tryAttack()
  turtle.dig()
  if turtle.place() then
    logger.debug("torch placed")
  end
  turtle.turnLeft()
  return true
end

-- trying refuel if fuel level < 200.
-- returns false if fuel is out.
-- required slot 16.
function tryRefuel()
  while turtle.getFuelLevel() < 40 do
    if turtle.getItemCount(16) < 1 then
      logger.info("reserve fuel is out!")
      return false
    end
    turtle.select(16)
    turtle.refuel(1)
  end
  return true
end

-- checking free space, placing chest
-- and transfering all items. returns
-- false if chests is out. required slot 14.
function tryGetFreeSpace()
  if turtle.getItemCount(12) > 0 then
    logger.info("need free space")
    if turtle.getItemCount(14) < 1 then
      logger.info("chests is out")
      return false
    end
    turtle.select(14)
    turtle.digDown()
    turtle.placeDown()
    for i = 1, 13 do
      turtle.select(i)
      turtle.dropDown(64)
    end
    logger.info("items transfered to chest")
    turtle.select(1)
  end
  return true
end


function stop()
  logger.error("Check chests, torches and fuel!")
end

-- turtle doing "count" step forward, dig
-- all blocks by the way, attacks detected
-- mobs, placing torch, refueling and
-- dig friable blocks by top if "isDigFriable"
function step(count)
  count = count + 1
  count = count - 1
  logger.info("step("..count..") working...")
  local iter = 0
  for i = 1, count do
    logger.trace("step: "..i)
    if not tryRefuel() then break end
    tryDigUp()
    tryDigDown()
    if not tryGetFreeSpace() then em:stop() break end
    while turtle.forward() == false do
      tryDigForward()
      tryAttack()
    end
    logger.debug("moved by 1 block")
    iter = i
    if i % 10 == 6 then
      if not tryPlaceTorch() then em:stop() break end
    end
  end
  logger.info("step("..iter..") of "..count.." done")
  if iter == count then return true
  else return false end
end