farming

--Farmimg
--Dustin Luhmann
--Version 0.1.1
--3/5/2015
--http://pastebin.com/NqH36dT5

--[[TO RUN: pastebin get NqH36dT5 <filename>; <filename>]]
--Example > pastebin get NqH36dT5 test
--        > test

-- USER NOTES (**IMPORTANT**)
-- 1) Must be placed facing north
-- 2) Seeds should be placed in slots 1 - 7
-- 3) Bonemeal should be placed in slot 8
-- 4) Nothing should be in slots 9 - 15
-- 5) A crop sensor card should be placed in slot 16

os.loadAPI("ocs/apis/sensor")
mySensor = sensor.wrap("left")

HEADINGS = {"north","east","south","west"}

WHEAT_IDX = 1
CROP_TWO_IDX = 2
CROP_THREE_IDX = 3
BONE_MEAL_IDX = 8
SENSOR_CARD_SLOT = 16

isUp = false
heading = 1

currentPosition = vector.new(0,0,0)

function tablelength(T)
  local count = 0
  for _ in pairs(T) do count = count + 1 end
  return count
end

function forward()
    if HEADINGS[heading] == "north" then
        currentPosition["z"] = currentPosition["z"] - 1
    elseif HEADINGS[heading] == "south" then
        currentPosition["z"] = currentPosition["z"] + 1
    elseif HEADINGS[heading] == "east" then
        currentPosition["x"] = currentPosition["x"] + 1
    elseif HEADINGS[heading] == "west" then
        currentPosition["x"] = currentPosition["x"] - 1
    end
    turtle.forward()
end

function turnLeft()
    if HEADINGS[heading] == "north" then
        heading = 4
    else
        heading = heading - 1
    end
    turtle.turnLeft()
end

function turnRight()
    if HEADINGS[heading] == "west" then
        heading = 1
    else
        heading = heading + 1
    end
    turtle.turnRight()
end

function pickUpNormalCrop()
    turtle.digDown()
end

function placeSeed(idx)
    turtle.select(idx)
    turtle.placeDown()
    if turtle.getItemCount(idx) == 0 then
    end
end

function tillLand()
    turtle.digDown()
end

function plantCrop(idx)
    tillLand()
    placeSeed(idx)
    useBoneMeal()

end

function useBoneMeal()
    turtle.select(BONE_MEAL_IDX)
    count = turtle.getItemCount(BONE_MEAL_IDX)
    turtle.placeDown()
    while turtle.getItemCount(BONE_MEAL_IDX) ~= count do
        count = turtle.getItemCount(BONE_MEAL_IDX)
        turtle.placeDown()
    end
end

function scan()
    targets = mySensor.getTargets()
    numberOfPlantsToCollect = 0
    plantLocations = {}

    for target, key in pairs(targets) do

      for attribute, attributeKey in pairs(mySensor.getTargetDetails(target)) do
        if attribute == "Position" then
            for direction, value in pairs(attributeKey) do
                if direction == "Y" then
                    y = value
                end
                if direction == "X" then
                    x = value
                end
                if direction == "Z" then
                    z = value
                end
            end
            location = vector.new(x,y,z)
        end
        if attribute == "Status" then
            if attributeKey == "Grown" then
                numberOfPlantsToCollect = numberOfPlantsToCollect + 1
                plantLocations[numberOfPlantsToCollect] = location
            end
        end
      end
    end
    return plantLocations
end

function move(location)
    if not isUp then
        moveInZ()
    end
    if location["x"] > 0 then
        while HEADINGS[heading] ~= "east" do
            turnLeft()
        end
    end
    if location["x"] < 0 then
        while HEADINGS[heading] ~= "west" do
            turnLeft()
        end
        location["x"] = -1 * location["x"]
    end

    for i = 1, location["x"] do
        forward()
    end

    if location["z"] > 0 then
        while HEADINGS[heading] ~= "south" do
            turnLeft()
        end
    end

    if location["z"] < 0 then
        while HEADINGS[heading] ~= "north" do
            turnLeft()
        end
        location["z"] = -1 * location["z"]
    end

    for i = 1, location["z"] do
        forward()
    end

end

function calculateHome()
    return home - currentPosition
end

function goHome()
    if currentPosition["x"] ~= home["x"] or currentPosition["y"] ~= home["y"] or currentPosition["z"] ~= home["z"] then
        move(calculateHome())
        while HEADINGS[heading] ~= "north" do
            turnLeft()
        end
        if isUp then
            moveInZ()
        end
    end
end

function moveInZ()
    if isUp then
        isUp = false
        turtle.down()
    else
        isUp = true
        turtle.up()
    end
end

function goToWork()
    while true do
        plantLocations = scan()
        if (tablelength(plantLocations) == 0) then
            goHome()
        else
            move(plantLocations[1])
            pickUpNormalCrop()
            plantCrop(WHEAT_IDX)
        end
    end
    return
end

function exitListen()
    while true do
      print( "Press Space exit program." )
      print("Farming...")
      local event, key = os.pullEvent( "key" ) -- limit os.pullEvent to the 'key' event

      if key == keys.space then -- if the key pressed was 'e'
        print( "You pressed [Space]. Exiting program..." )
        break
      end
    end
    return
end

function run()
    home = vector.new(0,0,0)
    parallel.waitForAny(goToWork, exitListen)
    goHome()
end

run()