local component = require("component")
local event = require("event")
local term = require("term")
local fs = require("filesystem")
local gsm = require("gsm")
local ini = require("ini")

local addresses = {"АДРЕС ПК ДЛЯ ПИЧАТИ КАРТ", "АДРЕС БАНКОМАТА"}
local DATA_RAID = "f45"
local LISTEN_PORT = 812
local PAYMENT_IDENT = "4"
local BANK_IDENT = "27630"

term.clear()
print("Банк-сервер запущен.")

function check_luhn(number)
  local final_amount = 0
  for i = 1, #number do
    if (i % 2) == 0 then
      final_amount = final_amount + number:sub(i, i)
    else
      if (number:sub(i, i) * 2) > 9 then
        final_amount = final_amount + (number:sub(i, i) * 2 - 9)
      else
        final_amount = final_amount + (number:sub(i, i) * 2)
      end
    end
  end
  if (final_amount % 10) == 0 then
    return true
  else
    return false
  end
end

function contains(array, element)
  for _, value in pairs(array) do
    if value == element then
      return true
    end
  end
  return false
end

function split(s, delimiter)
    result = {};
    for match in (s..delimiter):gmatch("(.-)"..delimiter) do
        table.insert(result, match);
    end
    return result;
end

function handler()
  local request = gsm.listen(LISTEN_PORT)
  local data = split(request[5], ":")
  if data[1] == "new_card" then
    print("Запрос на регистрацию новой карты.")
    if contains(addresses, request[3]) then
      if #data == 2 then
        local number_card = PAYMENT_IDENT .. BANK_IDENT
        while true do
          for i = 1, 9 do
            number_card = number_card .. math.random(0, 9)
          end
          for i = 0, 9 do
            if check_luhn(number_card .. i) then
              number_card = number_card .. i
              break
            end
          end
          if not fs.exists("/mnt/" .. DATA_RAID .. "/cards/" .. number_card .. ".card") then
            break
          end      
        end
        local CVC = math.random(100, 999)
        local PIN = math.random(1000, 9999)
        ini.saveFile("/mnt/" .. DATA_RAID .. "/cards/" .. number_card .. ".card", {number = number_card, owner = data[2], cvc = CVC, pin = PIN, balance = 0})
        gsm.send(request[3], request[4], "success:" .. number_card .. ":" .. data[2] .. ":" .. CVC .. ":" .. PIN)
      else
        gsm.send(request[3], request[4], "invalid_structure")
      end
    end   
  end
  if data[1] == "get_card" then
    print("Запрос на получение информации о карте.")
    if contains(addresses, request[3]) then
      if #data == 2 then
        if fs.exists("/mnt/" .. DATA_RAID .. "/cards/" .. data[2] .. ".card") then
          local card = ini.loadFile("/mnt/" .. DATA_RAID .. "/cards/" .. data[2] .. ".card")
          gsm.send(request[3], request[4], "success:" .. card["number"] .. ":" .. card["owner"] .. ":" .. card["cvc"] .. ":" .. card["balance"] .. ":" .. card["pin"])
        else
          gsm.send(request[3], request[4], "card_not_found")
        end        
      else
        gsm.send(request[3], request[4], "invalid_structure")
      end      
    end    
  end
  if data[1] == "deposit" then
    print("Запрос на депозит карты [ATM].")
    if contains(addresses, request[3]) then
      if #data == 3 then
        if fs.exists("/mnt/" .. DATA_RAID .. "/cards/" .. data[2] .. ".card") then
          local card = ini.loadFile("/mnt/" .. DATA_RAID .. "/cards/" .. data[2] .. ".card")
          card["balance"] = card["balance"] + data[3]
          ini.saveFile("/mnt/" .. DATA_RAID .. "/cards/" .. data[2] .. ".card", card)
          gsm.send(request[3], request[4], "success")                   
        else
          gsm.send(request[3], request[4], "card_not_found")
        end
      else
        gsm.send(request[3], request[4], "invalid_structure")
      end
    end
  end
end

while true do
  pcall(handler)
end