planter

-- pastebin get -f REyTTip0 planter.lua

local ms = require("movescript")
local robot = require("robot")
local component = require("component")
local sides = require("sides")
local ic = component.inventory_controller
local geolyzer = component.geolyzer

-- The list of names of all blocks that crops may be planted on.
local PLANTABLE_BLOCKS = {
  "minecraft:dirt",
  "minecraft:grass",
  "biomesoplenty:dirt",
  "biomesoplenty:grass"
}

local PICKAXE_NAME = "pickaxe"
local HOE_NAME = "mattock"

local DISPLACEMENT = -1 -- Displacement == 0 means we're on the first row of the field.

local function equipNothing()
  for i = 1, robot.inventorySize() do
    if robot.count(i) == 0 then
      robot.select(i)
      ic.equip()
      return true
    end
  end
  return false
end

local function dropAllExcept(names)
  for i = 1, robot.inventorySize() do
    local stack = ic.getStackInInternalSlot(i)
    if stack ~= nil then
      local shouldDrop = true
      for _, acceptableName in ipairs(names) do
        if string.find(stack.name, acceptableName) then
          shouldDrop = false
        end
      end
      if shouldDrop then
        robot.select(i)
        robot.dropDown()
      end
    end
  end
end

local function equipItemOrWait(name, cropName)
  -- First, ensure that nothing is equipped.
  repeat
    local success = equipNothing()
    if not success then
      dropAllExcept({PICKAXE_NAME, HOE_NAME, cropName})
    end
  until success
  -- Then try and select the item until we succeed.
  repeat
    local success = ms.selectItem(name)
    if not success then
      print("Please add more " .. name .. ", then press enter.")
      io.read()
    end
  until success
  ic.equip()
end

local function ensureEnoughEnergy()
  if ms.getEnergyRatio() < 0.05 then
    while ms.getEnergyRatio() < 0.5 do
      print("Energy low! Sleeping for a while.")
      os.sleep(60)
    end
  end
end

-- Moves from the current position to the next planting spot (just above grass).
-- Returns false if no spot could be found.
local function goToNextSpot(cropName)
  ensureEnoughEnergy()
  equipItemOrWait(PICKAXE_NAME, cropName)
  -- Go up to try and get around an obstacle, or give up if we can't.
  while robot.detect() do
    if not robot.up() then return false end
  end
  ms.exec("F")
  DISPLACEMENT = DISPLACEMENT + 1
  local grassFound = false
  while true do
    local blocking, desc = robot.detectDown()
    -- If we hit a liquid, quit right away.
    if not blocking and desc == "liquid" then return false end
    if blocking then -- There is something blocking the robot's path.
      -- If the block below us is something passable or an entity, keep swinging until it's gone.
      if desc == "passable" or desc == "entity" then
        repeat
          ms.exec("Sd")
        until not robot.detectDown()
      end
      if desc == "solid" then
        local blockData = geolyzer.analyze(sides.bottom)
        -- If for some reason we can't analyze the block, quit.
        if blockData == nil then return false end
        for _, plantableBlockName in ipairs(PLANTABLE_BLOCKS) do
          if blockData.name == plantableBlockName then
            ms.exec("U")
            return true
          end
        end
        -- If we reached a solid block that's not plantable, quit and return false.
        if not grassFound then return false end
      end
    else -- The robot is free to move down.
      ms.exec("D")
    end
  end
end

local function plantSpot(cropName)
  repeat
    equipItemOrWait(HOE_NAME, cropName)
    robot.useDown()
    equipItemOrWait(cropName, cropName)
    local success = robot.useDown()
  until success
end

local function plantUnboundedLength(width, cropName)
  for col = 1, width do
    -- Go as far as possible in this column.
    repeat
      local success = goToNextSpot(cropName)
      if success then
        plantSpot(cropName)
      end
    until not success
    -- We've reached the end. Go all the way back, then go into the next column.
    ms.exec("RR")
    while DISPLACEMENT ~= 0 do
      while not robot.detectDown() do
        ms.exec("D")
      end
      while robot.detect() do
        ms.exec("U")
      end
      ms.exec("F")
      DISPLACEMENT = DISPLACEMENT - 1
    end
    ms.exec("L")
    print("Completed column " .. col .. " of " .. width)
    if col ~= width then
      goToNextSpot(cropName)
      plantSpot(cropName)
      DISPLACEMENT = 0 -- Reset our global displacement tracker before going on the next run.
    end
    ms.exec("L")
  end
end

local function plantArea(length, width, cropName)
  goToNextSpot(cropName)
  plantSpot(cropName)
  ms.exec("R")
  for row = 1, length do
    for col = 1, width - 1 do
      goToNextSpot(cropName)
      plantSpot(cropName)
    end
    if row % 2 == 1 then
      ms.exec("L")
    else
      ms.exec("R")
    end
    if row ~= length then
      goToNextSpot(cropName)
      plantSpot(cropName)
    end
    if row % 2 == 1 then
      ms.exec("L")
    else
      ms.exec("R")
    end
    print("Completed row " .. row .. " of " .. length)
  end
end


if ic == nil then error("Missing inventory controller component.") end
if geolyzer == nil then error("Missing geolyzer component.") end

local arg = {...}

local length = tonumber(arg[1])
local width = tonumber(arg[2])
local cropName = arg[3]
if not length or not width or not cropName then
  error("Invalid args.")
end

if length < 0 and width > 0 then
  print("Planting area " .. width .. " blocks wide, with unbounded length, with " .. cropName)
  plantUnboundedLength(width, cropName)
  return
end

print("Planting an area " .. length .. " by " .. width .. " with " .. cropName .. ".")
plantArea(length, width, cropName)