CactusFarm

local farmY
local initialX
local initialZ
local finalX
local finalZ
local farmDelay
local state = "notDefined"
local chestPosition
local checkInterval = 60
local tempVar = {}

function loadFarmInfo()
  if fs.exists("FarmInfo") then
    local file = fs.open("FarmInfo","r")
    for i=0,6 do
      tempVar[i] = tonumber(file.readLine())
    end
    file.close()
    farmY = tempVar[0]
    initialX = tempVar[1]
    initialZ = tempVar[2]
    finalX = tempVar[3]
    finalZ = tempVar[4]
    farmDelay = tempVar[5]
    chestPosition = tempVar[6]

  else
    requestFarmInfo()
  end
end

--Defines the farm information
function requestFarmInfo()
  write("Farm Y level: ")
  farmY = read()
  write("Initial X: ")
  initialX = read()
  write("Initial Z: ")
  initialZ = read()
  write("Final X: ")
  finalX = read()
  write("Final Z: ")
  finalZ = read()
  write("How many seconds to wait between each cycle: ")
  farmDelay = read()
  write("Chest position (number) relative to turtle home: ")
  chestPosition = read()

  local file = fs.open("FarmInfo","w")
  file.writeLine(farmY)
  file.writeLine(initialX)
  file.writeLine(initialZ)
  file.writeLine(finalX)
  file.writeLine(finalZ)
  file.writeLine(farmDelay)
  file.writeLine(chestPosition)
  file.close()
end


--Performs an action in a line
function doLine(towardsFinal,action)
  if towardsFinal then
    while x ~= finalX do
    performAction(action)
      if initialX > finalX then
        shell.run("goto",x-1,y,z)
      else
        shell.run("goto",x+1,y,z)
      end
    end

  else
    while x ~= initialX do
      performAction(action)
      if initialX > finalX then
        shell.run("goto",x+1,y,z)
      else
        shell.run("goto",x-1,y,z)
      end
    end
  end
performAction(action)
end

--Performs an action
function performAction(action)
  if action == "collect" then
    suckAround()
  elseif action == "plant" then
    selectCactus()
    turtle.placeDown()
  end
end

--Suck every direction to collect everything
function suckAround()
  while turtle.suckUp() do end
  while turtle.suckDown() do end
  for i = 0,3 do
    while turtle.suck() do end
    shell.run("turnRight")
  end
end

--Performs an action on the whole farm
function doFarm(action)
  --Boolean variable that stores the direction the turtle has to go
  local towardsFinal

  --Decide which direction the turtle has to go
  if (finalZ - initialZ)%2 == 0 then
    if (finalZ - z)%2 == 0 then
      towardsFinal = true
    else
      towardsFinal = false
    end
  else
     if(finalZ - z)%2 == 0 then
       towardsFinal = false
     else
       towardsFinal = true
     end
  end

  --Call doLine for each line, until it reaches the final position
  while z ~= finalZ do
    doLine(towardsFinal,action)
    if initialZ > finalZ then
      shell.run("goto",x,y,z-1)
    else
      shell.run("goto",x,y,z+1)
    end
    --switch the direction the turtle has to go
    towardsFinal = not towardsFinal
  end
  doLine(towardsFinal,action)
end

--Select the cactus to be planted
function selectCactus()
  for i=1,15 do
    turtle.select(i)
    if turtle.compareTo(16) then
      break
    end
  end
end

--Stores what the turtle just collected
function dropOff()
  for i=1,15 do
    turtle.select(i)
    turtle.drop()
  end
  turtle.select(16)
  local toDrop = turtle.getItemCount(16) - 1
  turtle.drop(toDrop)
end

--Saves the state of the turtle in a file, in case of reboot
function registerState(newState)
  state = newState
  file = io.open("StateFile","w")
  file:write(state)
  file:close()
  displayInfo()
end

--In case of reboot, this function will be called
function loadState()
  if fs.exists("StateFile") then
    print("Loading State")
    file = io.open("StateFile","r")
    state = file:read()
    file:close()
    displayInfo()
  else
    print("No state found, defining goHome")
    state = "goHome"
  end
end

function displayInfo()
  term.clear()
  term.setCursorPos(1,1)
  write("State: "..state)
  term.setCursorPos(1,2)
  write("Fuel Level: "..turtle.getFuelLevel())
  term.setCursorPos(1,3)
  write("Order: ")
end

-- Main Code --
function main()
while(true) do

--Check for fuel
if turtle.getFuelLevel() < 100 then
  write("Out of Fuel \n")
  break
end

if state == "notDefined" then
  loadState()
end

if state == "collect" then
  doFarm("collect")
  registerState("goOriginUp")
end

if state == "goOriginUp" then
  shell.run("goto",initialX,farmY+1,initialZ)
  registerState("plant")
end

if state == "plant" then
  doFarm("plant")
  registerState("goHome")
end

if state == "goHome" then
  shell.run("gohome")
  shell.run("setFacing",chestPosition)
  dropOff()
  registerState("wait"..farmDelay)
end

if string.match(state,"wait") == "wait" then
  time = string.match(state,"%p*%d+")
  time = tonumber(time)
  if time <= 0 then
    registerState("goOrigin")
  else
    sleep(checkInterval)
    time = time - checkInterval
    registerState("wait"..time)
  end
end

if state == "goOrigin" then
  turtle.select(1)
  shell.run("goto",initialX,farmY,initialZ)
  registerState("collect")
end

end

end

function readInput()
  while (true) do
    term.setCursorPos(8,3)
    local input = read()
    if input == "quit" then
      term.clear()
      return
    end
    if input == "resetFarm" then
      term.clear()
      fs.delete("FarmInfo")
      return
    end
  end
end

loadFarmInfo()
--Run the farm program parallel to the readInput function, so you can give orders while the turtle works
parallel.waitForAny(readInput, main)