Farmer

-- to come back to original values after one whole loop
local backupX
local backupY

local timesx
local timesy
local timesxBackup = 0 -- save value for each row
local timesyBackup = 0
-- if work interrupted by anything, continue on position
local returnPointX = 0
local returnPointY = 0

local Totaltimes = 0
local checkpointDigs
local isDown = false

-- return to chest and deposit
function Return()

    checkpointDigs = 200 -- reset checkpoint counter
    print("Master, im full. Heading back to deposit.")
    returnPointX = timesx
    returnPointY = timesy
    if isDown == false then -- if straight
        print("up")
        turtle.turnLeft()
        if (timesyBackup - timesy) >= 1 then
            for i=0,(timesyBackup - timesy - 1) do
                turtle.forward()
            end
        end
        turtle.turnLeft()
        local iBackx = (timesxBackup - timesx)
        for i=0,iBackx do
            turtle.forward()
        end
        turtle.turnRight()
        turtle.turnRight()
    else -- if turtle comes down
        -- when not at 0 we need to add 1 step
        local down = timesx
        if not timesx == 0 then
            down = down + 1
        end
        for i=0,down do
            turtle.forward()
        end
        turtle.turnRight()
        local iBacky = (timesyBackup - timesy)
        if iBacky >= 1 then
            for i=0,(timesyBackup - timesy - 1) do
                turtle.forward()
            end
        else
            for i=0,timesyBackup - 1 do
                turtle.forward()
            end
        end
        turtle.turnRight()
    end
        -- back to chest
    --turtle.back()
    turtle.down()
    turtle.down()
    turtle.turnRight()
    turtle.turnRight()
    local invcount = 1
    repeat
        turtle.select(1+invcount)
        turtle.drop()
        invcount = invcount + 1
    until invcount == 16
    turtle.select(1)
    turtle.turnRight()
    turtle.turnRight()
    turtle.up()
end

-- continue where it left
function Continue()
    -- used for counting
    local tempX = returnPointX
    local tempY = returnPointY
    print("Going back to work at:",returnPointX, returnPointY)

    -- if straight
    if isDown == false then
       for i=0, (timesxBackup - returnPointX) do
        turtle.forward()
      end

      turtle.turnRight()

        if (timesyBackup - returnPointY) >= 1 then
            for i=0, (timesyBackup - returnPointY) do
                turtle.forward()
            end
        end
      turtle.turnLeft()


    -- if turtle comes dow
    else
      turtle.turnRight()
      if (timesyBackup - returnPointY) > 1 then
            for i=0, (timesyBackup - returnPointY - 1) do
                turtle.forward()
            end
        elseif (timesyBackup - returnPointY) == 1 then
            turtle.forward()
      end
      turtle.turnLeft()
      for i=0, returnPointX do
        turtle.forward()
      end
      turtle.turnRight()
      turtle.turnRight()
    end
    -- restore pos
    timesx = returnPointX
    timesy = returnPointY
end

-- place, till and farm
function work(inTransition)
    inTransition = inTransition or false
    -- print("X Y: ", timesx, timesy)
    -- print("Blocks before return: ", checkpointDigs)
    if (checkpointDigs == 0 and inTransition == false)  then
        Return()
        Continue()
        -- print("restored: ", timesx, timesy)
    end
    local success, data = turtle.inspectDown()
    if  data.name == "minecraft:wheat" then -- try to place crop
        turtle.digDown() -- till
        turtle.placeDown() -- place crop
        turtle.suckDown() -- suck it up
    elseif data.name == "minecraft:water" then -- when air just dig
        -- maybe print soemthing?
    else -- if just dirt or sth
        turtle.digDown() -- till
        turtle.placeDown() -- place crop
    end
end

-- do everything
function Start()
    isDown = false
    if timesy == 0 then
        timesy = timesx -- make square
    end
    backupX = timesx
    backupY = timesy
    while true do
        Totaltimes = Totaltimes + 1
        timesx = backupX
        timesy = backupY
        turtle.down() -- try to move down initially
        turtle.up()
        turtle.forward()
        turtle.select(1) -- select crops
        timesxBackup = timesx -- save value for each row
        timesyBackup = timesy
        repeat -- until horizonal line complete
            repeat -- until straight line complete
                timesx = timesx -1
                turtle.forward()
                work()
                checkpointDigs = checkpointDigs -1 -- count sucks (can only suck 256 times then he might be full: 64x16=1024 / 4 = 256)
            until timesx == 0
            -- turn around <
            if (timesyBackup - timesy)%2 == 0 then -- if EVEN turn right
                turtle.turnRight()
                turtle.forward()
                work(true)
                turtle.turnRight()
                isDown = true
            else -- odd turn left
                turtle.turnLeft()
                turtle.forward()
                work(true)
                turtle.turnLeft()
                isDown = false
            end
            -- > turn around
            timesx = timesxBackup
            timesy = timesy -1
        until timesy == 0
        Return()
        print("Im done Master. Sleeping for 30 min. Please dont hurt me.")
        print("I already farmed so many times: ", Totaltimes)
        os.sleep(1800)
    end
end

print("Please place seeds in the first slot")
print("How long (vertical)?")
local input
input = io.read()
timesx = tonumber(input)
print("How far to the right (horizontal)? 0 for square")
input = io.read()
timesy = tonumber(input)
checkpointDigs = 200
Start()