Farm

os.loadAPI("JAPI/JMove.lua")

-- /\ +y (FORWARD)
-- |   F F F
-- |   F F F
-- |   F F F
-- | T F F F
-- ---------> +x

function printUsage()
    textutils.pagedPrint("Usage: farm <width> <length> <farm dir up>")
    textutils.pagedPrint("     <farm dir up> can be a number or a string.")
    textutils.pagedPrint("     Number: 0 .. 3")
    textutils.pagedPrint("     String: FORWARD/POS_Y, LEFT/NEG_X, BACK/NEG_Y or RIGHT/POS_X")
    error()
end

local tArgs = { ... }
if #tArgs ~= 3 then
    printUsage()
    return
end

local farmWidth = tArgs[1]
local farmLength = tArgs[2]
local farmDirUp = tArgs[3]

local success, data = JMove.isDir(farmDirUp)
if success == false then
    printUsage()
    return
end

local farmItemType = "minecraft:wheat"
local farmItemSeedType = "minecraft:wheat_seeds"
local waitTime = 2

function waitToBegin()
    JMove.turnTo(JMove.POS_X)
    local begin = false
    while begin == false do
        sleep(waitTime)
        local s, d = turtle.inspect()
        if s then
            print("Waiting...")
            if d.name == farmItemType then
                local age = d.state.age
                if age == 7 then
                    print("Initiate farming")
                    begin = true
                end
            end
        else
            print("Wheat at (0, 0, 0) is gone!")
           begin = true
        end
    end
end

function dumpItems()
    JMove.turnTo(JMove.NEG_Y)
    local numSeeds = 0
    local shouldDumpSeeds = false
    for i=1, 16, 1 do
        turtle.select(i)
        local data = turtle.getItemDetail()
        if data then
            if data.name == farmItemSeedType then
                if shouldDumpSeeds == false then
                    numSeeds = numSeeds + data.count
                    local numFarmBlocks = farmWidth*farmLength
                    if numSeeds > numFarmBlocks then
                        local dropCount = numSeeds-numFarmBlocks
                        shouldDumpSeeds = true
                        turtle.drop(dropCount)
                    end
                else
                    turtle.drop()
                end
            elseif data.name == farmItemType then
                turtle.drop()
            end
        end
    end
end

function reset()
    JMove.setPos(-1, 0, -1)
    JMove.setPOSY(farmDirUp)

    dumpItems()
    waitToBegin()
end

function toStart()
    reset()
    JMove.refuel()
    JMove.moveTo(-1, 0, 0)
    JMove.moveTo(0, 0, 0)
end

function placeSeed()
    local seeds = JUtils.findItem(farmItemSeedType)
    if seeds then
        turtle.placeDown()
        local s, d = turtle.inspectDown()
        if s then
            if d.name ~= farmItemType then
                print("Warning: Tile at", JMove.posToStr(), "is blocked!")
            else
                print("Placed seed at", JMove.posToStr())
            end
        else
            -- Till the dirt block
            local couldTill= turtle.digDown()
            if couldTill == false then
                print("Warning: Missing dirt block at", JMove.posToStr(), "!")
            else
                turtle.placeDown()
                print("Tilled and placed seed at", JMove.posToStr(), "!")
            end
        end
    else
        print("No seeds was found, add seeds and press 'enter' when done!")
        local hasSeeds = false
        while hasSeeds == false do
            action, key = os.pullEventRaw()
            if action == "key" then
                if key == keys.enter then
                    local seeds = JUtils.findItem(farmItemSeedType)
                    if seeds then
                        hasSeeds = true
                    else
                        print("That was not seeds, try again and press 'enter' when done!")
                    end
                end
            end
        end
        placeSeed()
    end
end

function farm()
    local success, data = turtle.inspectDown()
    if success then
        if data.name == farmItemType then
            local age = data.state.age
            -- Destroy is full grown
            if age == 7 then
                turtle.digDown()
                print("Farmed wheet at", JMove.posToStr(), "!")
                placeSeed()
            end
        end
    else
        placeSeed()
    end
end

local fw = farmWidth-1
local fh = farmLength-1
while true do
    toStart()
    farm()

    y = 0
    repeat
        local xStart = fw-1
        local xEnd = 0
        local xStep = -1
        if y%2 == 0 then
            xStart = 1
            xEnd = fw
            xStep = 1
        end
        if y ~= 0 then
            local i = xStart + 1
            if y%2 == 0 then i = 0 end
            JMove.moveTo(i, y, 0)
            farm()
        end
        for x=xStart,xEnd,xStep do
            JMove.moveTo(x, y, 0)
            farm()
        end
        y = y + 1
    until y > fh

    -- Move back to starting position on the farm.
    JMove.moveTo(0, 0, 0)
    JMove.moveTo(-1, 0, 0)
    JMove.moveTo(-1, 0, -1)
    JMove.turnTo(farmDirUp)
end