Automation Miner v1.2

-- Automation Miner v1.2

local minFuel = 200

function beginning()
    if peripheral.isPresent("bottom") then
        turtle.suckDown()
        turtle.digDown()
        turtle.select(3)
        turtle.drop()
        turtle.select(2)
        turtle.drop()
        turtle.turnLeft()
        turtle.turnLeft()
        turtle.select(1)
    end
end
beginning()

function forward()
    checkFuel()
    return turtle.forward()
end

function back()
    checkFuel()
    return turtle.back()
end

function up()
    checkFuel()
    return turtle.up()
end

function down()
    checkFuel()
    return turtle.down()
end

function returnToChest(mines,height,start)
    if turtle.getItemCount(16) > 0 then
        for i = 1, height do
            if not up() then
                repeat
                    turtle.digUp()
                until up()
            end
        end
        turtle.turnLeft()
        turtle.turnLeft()
        for i = 1, mines * 4  do
            repeat
                if turtle.detect() then
                    turtle.dig()
                end
            until forward()
        end
        for i = start, 16 do
            turtle.select(i)
            repeat until ({turtle.drop()})[2] == "No items to drop"
        end
        turtle.turnLeft()
        turtle.turnLeft()
        for i = 1, mines * 4  do
            repeat
                if turtle.detect() then
                    turtle.dig()
                end
            until forward()
        end
        for i = 1, height do
            repeat
                if turtle.detectDown() then
                    turtle.digDown()
                end
            until down()
        end
        turtle.select(1)
    end
end
function checkFuel()
    if turtle.getFuelLevel() < minFuel and turtle.getFuelLevel() ~= "unlimited"  then
        for p = 1, 16 do
            turtle.select(p)
            repeat
            until turtle.getFuelLevel() >= minFuel or not turtle.refuel(64)
            if turtle.getFuelLevel() >= minFuel then
                break
            end
            if p == 16 then
                print("Failed to refuel.")
            end
        end
        turtle.select(1)
    end
end
function verticalMine(mines)
    -- Move back two to get to original position
    -- Move forward four to get to next position
    local i = 0
    while true do
        repeat
            returnToChest(mines,i,1)
        until not turtle.dig()
        if not down() then
            returnToChest(mines,i,1)
            if turtle.digDown() then
                if down() then
                    i = i + 1
                else
                    break
                end
            else
                break
            end
        else
            i = i + 1
        end
    end
    -- Mining is done at this point
    for o = 1, 2 do
        repeat
            turtle.dig()
            if forward() then
                break
            end
            if not up() then
                repeat
                    turtle.digUp()
                until up()
            end
            i = i - 1
        until forward()
    end
    local r = i + 0
    for o = 1, r do
        if turtle.getItemCount(16) > 0 then
            if not back() then
            turtle.turnLeft()
            turtle.turnLeft()
            for p = 1, 2 do
                if not forward() then
                    repeat
                        turtle.dig()
                    until forward()
                end
            end
            turtle.turnLeft()
            turtle.turnLeft()
            else
                if not back() then
                    turtle.turnLeft()
                    turtle.turnLeft()
                    if not forward() then
                        repeat
                            turtle.dig()
                        until forward()
                    end
                    turtle.turnLeft()
                    turtle.turnLeft()
                end
            end
            returnToChest(mines,(r + 1) - o,1)
            for p = 1, 2 do
                if not forward() then
                    repeat
                        turtle.dig()
                    until forward()
                end
            end
        end
        turtle.dig()
        if not up() then
            repeat
                turtle.digUp()
            until up()
        end
    end
end
local mines = ((#{...} > 0) and tonumber(({...})[1]) or 0)
while true do
    for i = 1, mines * 4 do
        repeat
            if turtle.detect() then
                turtle.dig()
            end
        until forward()
    end
    print("Starting vertical miner")
    verticalMine(mines)
    print("Ending vertical miner")
    turtle.turnLeft()
    turtle.turnLeft()
    for i = 1, ((mines + 1) * 4) - 2 do
        if not forward() then
            repeat
                turtle.dig()
            until forward()
        end
    end
    for i = 1, 16 do
        turtle.select(i)
        repeat until ({turtle.drop()})[2] == "No items to drop"
    end
    turtle.select(1)
    turtle.turnLeft()
    turtle.turnLeft()
    mines = mines + 1
end