settings.define("AES.key", {
    description = "AES key used for encryption",
    type = number
})

local printerSide = "right"
local modemSide = "top"

local channel = 59598

local AES = require("/AES")
local key = settings.get("AES.key") or error("No AES Key set")

local modem = peripheral.wrap(modemSide) or error("No modem found")
modem.closeAll()
modem.open(channel)

local printer = peripheral.wrap(printerSide) or error("No printer found")

function startPage()
    if not printer.newPage() then
        error("cant start new page")
    end
    printer.setPageTitle(os.date())
end

local pageOpened = false
function printNewLog(line)
    print(line)
    if not pageOpened then
        startPage()
        pageOpened = true
    end
    local width, height = printer.getPageSize()
    local currX, currY = printer.getCursorPos()

    local neededLines = math.ceil(#line / width)
    if neededLines > height+1 - currY then -- +1 because being on the last line still leaves one free
        startPage()
    end
    local i = 1
    while i <= #line do
        printer.write(line:sub(i, i + width-1))
        i = i + width - 1
        printer.setCursorPos(1, currY+1)
        currX, currY = printer.getCursorPos()
    end
    if currY == height then
        printer.endPage()
        pageOpened = false
    end
end


local modemMessage = {}
local decrypted = nil
local obj = nil
while true do
    modemMessage = {os.pullEvent("modem_message")}
    decrypted = AES.ECB_256(AES.decrypt, key, modemMessage[5])
    obj = textutils.unserialise(decrypted)
    if obj then
        if obj.sender and obj.message then
            printNewLog(string.format("%s %s: %s", os.date(), obj.sender, obj.message))
        else
            print("invalid object received")
            print(decrypted)
        end
    else
        print("invalid object received")
    end
end