donedistance = 0
leftdistance = 0
totaldistance = 0
doneblocks = 0
leftblocks = 0
totalblocks = 0
torchblocks = 0
status = false
height = 0
width = 0

function input()
    term.clear()
    term.setTextColor(colors.blue)
    term.setCursorPos(1, 1)
    term.write("Input tunnel width: ")
    temp = read()
    if tonumber(temp) == nil then
        input()
    else
        width = tonumber(temp)
        term.clear()
        term.setTextColor(colors.blue)
        term.setCursorPos(1, 1)
        term.write("Input tunnel height: ")
        temp = read()
        if tonumber(temp) == nil then
            input()
        else
            height = tonumber(temp)
            term.clear()
            term.setTextColor(colors.blue)
            term.setCursorPos(1, 1)
            term.write("Input tunnel distance: ")
            temp = read()
            if tonumber(temp) == nil then
                input()
            else
                totaldistance = tonumber(temp)
                totalblocks = height * width * totaldistance
                tunnel()
            end
        end
    end
end

function update()
    term.clear()
    term.setTextColor(colors.red)
    term.setCursorPos(1, 1)
    term.write("Total distance      : " .. totaldistance)
    term.setCursorPos(1, 2)
    term.write("Distance done       : " .. donedistance)
    term.setCursorPos(1, 3)
    term.write("Distance left       : " .. leftdistance)
    term.setCursorPos(1, 4)
    term.write("Total blocks        : " .. totalblocks)
    term.setCursorPos(1, 5)
    term.write("Blocks done         : " .. doneblocks)
    term.setCursorPos(1, 6)
    term.write("Blocks left         : " .. leftblocks)
    term.setCursorPos(1, 7)
    term.write("Next torch          : " .. (12 - torchblocks))
    term.setCursorPos(1, 8)
    if status == true then
        term.setTextColor(colours.green)
        term.write("Status              : Finished")
    else
        term.setTextColor(colours.red)
        term.write("Status              : Unfinished")
    end
end

function drop()
    right(2)
    for i = 1, donedistance do
        turtle.forward()
    end
    for i = 2, 15 do
        turtle.select(i)
        turtle.drop()
    end
    if status == false then
        right(2)
        for i = 1, donedistance do
            turtle.forward()
        end
    end
end

function move(direction)
    if direction == "for" then
        repeat
            turtle.dig()
            sleep(0.2)
        until turtle.forward() == true
        doneblocks = doneblocks + 1
        leftblocks = totalblocks - doneblocks
        update()
    elseif direction == "up" then
        repeat
            turtle.digUp()
            sleep(0.2)
        until turtle.up() == true
        doneblocks = doneblocks + 1
        leftblocks = totalblocks - doneblocks
        update()
    elseif direction == "dow" then
        repeat
            turtle.digDown()
            sleep(0.2)
        until turtle.down() == true
        doneblocks = doneblocks + 1
        leftblocks = totalblocks - doneblocks
        update()
    end
end

function left(amount)
    for i = 1, amount do
        turtle.turnLeft()
    end
end

function right(amount)
    for i = 1, amount do
        turtle.turnRight()
    end
end

function strip(width, height)
    halfwidth = math.floor(width / 2)
    move("for")
    for i = 1, height do
        left(1)
        for ii = 1, halfwidth do
            move("for")
            if i == 1 then
                turtle.select(1)
                turtle.placeDown()
            elseif i == height then
                turtle.select(1)
                turtle.placeUp()
            end
        end
        turtle.select(1)
        turtle.place()
        turtle.back()
        if i == 1 then
            if torchblocks == 12 then
                turtle.select(16)
                turtle.place()
                turtle.select(1)
                torchblocks = 0
            end
        end
        right(2)
        for ii = 1, (halfwidth - 1) do
            turtle.forward()
        end
        for ii = 1, halfwidth do
            move("for")
            if i == 1 then
                turtle.select(1)
                turtle.placeDown()
            elseif i == height then
                turtle.select(1)
                turtle.placeUp()
            end
        end
        turtle.select(1)
        turtle.place()
        turtle.back()
        if i == 1 then
            if torchblocks == 12 then
                turtle.select(16)
                turtle.place()
                turtle.select(1)
                torchblocks = 0
            end
        end
        left(2)
        for ii = 1, (halfwidth - 1) do
            turtle.forward()
        end
        right(1)
        move("up")
    end
    for i = 1, (height - 1) do
        turtle.down()
    end
    if turtle.getItemCount(15) > 0 then
        drop()
    end
end

function tunnel()
    for i = 1, totaldistance do
        strip(width, height)
        donedistance = donedistance + 1
        leftdistance = totaldistance + donedistance
        torchblocks = torchblocks + 1
        update()
    end
    status = true
    update()
end

input()