KopaczFull

local function digToNextFloor()
    turtle.down()
    turtle.digDown()
    turtle.down()
    turtle.digDown()
    turtle.down()
    turtle.digDown()
end

local function moveUp3()
    turtle.up()
    turtle.up()
    turtle.up()
end

local function moveDown3()
    turtle.down()
    turtle.down()
    turtle.down()
end


local function turnBack()
    turtle.turnRight()
    turtle.turnRight()
end

local function digForward()
    if turtle.detect() then
        turtle.dig()
    end
end

local function digUpAndDown()
    if turtle.detectUp() then
        turtle.digUp()
    end

    if turtle.detectDown() then
        turtle.digDown()
    end
end

local function moveForward()

    while turtle.detect() do
        turtle.dig()
        sleep(0.3)
    end
    if turtle.detect() == false then
        turtle.forward()
    end

end


local function startNextTunnel()
    if direction == "FORWARD" then
        turtle.turnRight()
        moveForward()
        digUpAndDown()
        turtle.turnRight()
        direction = "BACKWARD"
    else
        turtle.turnLeft()
        moveForward()
        digUpAndDown()
        turtle.turnLeft()
        direction = "FORWARD"
    end

end

local function inventoryFull()
    for i = 1,16 do
        if turtle.getItemCount(i) == 0 then
          return false
        end
    end
    return true
end

local function moveUp()
    if heightFromStart > 0 then
        for i = 1, heightFromStart do
            moveUp3()
        end
    end
end

local function moveBackToPosition()

    for i = 1, lengthFromStart do
        moveForward()
    end

    turtle.turnRight()

    for i = 1,widthFromStart do
        moveForward()
    end

    for i = 1, heightFromStart do
        moveDown3()
    end

    if direction == "FORWARD" then
        turtle.turnLeft()
    else
        turtle.turnRight()
    end

end

local function goToSliceStartPostion()

    if widthFromStart > 0 then
        if direction == "FORWARD" then
            turtle.turnLeft()
        else
            turtle.turnRight()
        end
        for i = 1, widthFromStart do
            moveForward()
        end
    else
        turtle.turnLeft()
    end

    turtle.turnLeft()
    for i = 1, lengthFromStart do
        moveForward()
    end

    turnBack()
end


local function moveAboveChest()
    turtle.back()
end

local function moveFromChest()
    moveForward()
end

local function dumpInventory()
    local firstItem,lastItem = 1,16
    for i=firstItem,lastItem do
        turtle.select(i)
        turtle.dropDown()
    end
end


local function refuel()
    --check current fuel level, find coal in inventory add to fuel level
    while turtle.getFuelLevel() < (length * width) * 2 do
        for i = 1, 16 do -- loop through the slots
            turtle.select(i) -- change to the slot
            if turtle.refuel(0) then -- if it's valid fuel
                local halfStack = math.ceil(turtle.getItemCount(i)/2) -- work out half of the amount of fuel in the slot
                turtle.refuel(halfStack) -- consume half the stack as fuel
                break
            end
        end
    end
end

local function digSlice()

    while widthLeft > 0 do

        digForward()
        moveForward()
        digUpAndDown()
        lengthLeft = lengthLeft - 1

        if direction == "FORWARD" then
            lengthFromStart = lengthFromStart + 1
        else
            lengthFromStart = lengthFromStart - 1
        end

        refuel()

        if inventoryFull() then
            goToSliceStartPostion()
            moveUp()

            moveAboveChest()
            dumpInventory()
            moveFromChest()

            moveBackToPosition()
        end

        if lengthLeft == 0 then
            lengthLeft = length - 1

            if widthLeft > 1 then
                startNextTunnel()
                widthFromStart = widthFromStart + 1
            end

            widthLeft = widthLeft - 1
        end
    end
end



local function digTunnels()

    digForward()
    moveForward()
    digUpAndDown()

    for level = 1, height do

        widthFromStart = 0
        lengthFromStart = 0
        lengthLeft = lengthLeft - 1
        digSlice()

        goToSliceStartPostion()
        heightLeft = heightLeft - 1

        widthLeft = width
        lengthLeft = length

        digToNextFloor()
        heightFromStart = heightFromStart + 1

        direction = "FORWARD"
    end

    goToSliceStartPostion()
    moveUp()

    moveAboveChest()
    dumpInventory()
end

--START--
print("Mining program")

print("Length of tunnel: ")
input = io.read()
length = tonumber(input)
lengthLeft = length
lengthFromStart = 0


print("Width of tunnel: ")
input = io.read()
width = tonumber(input)
widthLeft = width
widthFromStart = 0

print("Height of tunnel: ")
input = io.read()
height = tonumber(input)
heightLeft = height
heightFromStart = 0

direction = "FORWARD"

refuel()
digTunnels()