deconstruct

local args = {...}

if #args ~= 4 then
    print("Usage:")
    print("deconstruct <width> <length> <height> <file>")
    return
end

local blueprint = {}
blueprint.x = tonumber(args[1])
blueprint.y = tonumber(args[2])
blueprint.h = tonumber(args[3])
blueprint.slots = {}
blueprint.tcode = {}

local userFile = shell.resolve(args[4])

if fs.exists(userFile) then
    print("Error: A file by that name already exists")
    return
end

local bpFile = fs.open(userFile,"w")

--returns whatever slot the block was put into
function scan(up)
    local slotCounts = {}
    for i=1,16 do
        slotCounts[i] = turtle.getItemCount(i)
    end
    if up then
        turtle.digUp()
    else
        turtle.dig()
    end
    local slot = 0
    for i=1,16 do
        if turtle.getItemCount(i) > slotCounts[i] then
            slot = i
        end
    end
    if slot > 0 then
        --if slot hasn't been used yet
        if not blueprint.slots[slot] then
            --get item name for slot
            local item = turtle.getItemDetail(slot).name
            blueprint.slots[slot] = {name = item, count = 0}
        end
        --add 1 to the slot count
        blueprint.slots[slot].count = turtle.getItemCount(slot)
    end
    --add the slot number to the tcode
    return slot
end

local i = 1
local right = true
blueprint.tcode[i] = scan()
i = i + 1
turtle.forward()
for h=1,blueprint.h do
    for x=1,blueprint.x do
        for y=1,blueprint.y - 1 do
            blueprint.tcode[i] = scan()
            turtle.forward()
            i = i + 1
        end
        if x < blueprint.x then
            if right then
                turtle.turnRight()
                blueprint.tcode[i] = scan()
                i = i + 1
                turtle.forward()
                turtle.turnRight()
                right = false
            else
                turtle.turnLeft()
                blueprint.tcode[i] = scan()
                i = i + 1
                turtle.forward()
                turtle.turnLeft()
                right = true
            end
        end
    end
    if h < blueprint.h then
        blueprint.tcode[i] = scan(true)
        i = i + 1
        turtle.turnRight()
        turtle.turnRight()
        turtle.up()
    end
end

local output = textutils.serialize(blueprint)
bpFile.write(output)
bpFile.close()