Very basic turtle mining program

--Very basic turtle mining program.

function refuel()
local data
local success = false
    for i = 1, 16, 1 do
        turtle.select(i)
        data = turtle.getItemDetail()

        if data then
            if data.name == "minecraft:coal" then --refuel if coal found in internal storage
                turtle.refuel(turtle.getItemCount())
                success = true
            end
        end

        if turtle.getFuelLevel() == turtle.getFuelLimit() then --if already refueled no need to continue this function
            break
        end
    end
    if not success then
          print("Couldn't refuel!\n")
    end
    turtle.select(1)
    return success
end

function isFull()
local data
    for i = 1, 16, 1 do
        turtle.select(i)
        data = turtle.getItemDetail()

        if not data then
            do return false end
        end
    end
    turtle.select(1)
    return true
end

function isStorage(chestName)
    local success, data = turtle.inspect()

    if success then
        if data.name == chestName then
            do return true end
        end
    end
    return false
end

function goBackHome(chestName)
    turtle.turnLeft()
    turtle.turnLeft() --180°

    while not isStorage(chestName) do
        turtle.forward()
    end
end

function store()
local success
    for i = 1, 16, 1 do
        turtle.select(i)
        success = turtle.drop()

        if not success then
            do return false end
        end
    end

    turtle.turnRight()
    turtle.turnRight()

    turtle.select(1)
    return true
end

--main
local storageChestName = "minecraft:chest"
local canStillWork= true

while true do
    if turtle.getFuelLevel() == 0 then
        canStillWork = refuel()
    elseif isFull() then
        goBackHome(storageChestName)
        canStillWork = store()
    else
        turtle.dig()
        turtle.up()
        turtle.dig()
        turtle.down()
        turtle.forward()
    end

    if not canStillWork then
        break
    end
end

print("Job finished!")