AntiVirus

local findtable=function(txt)
--[[ Broken Stub
local t
if not string.find(txt, ".") then return (string.sub(txt, {string.find(txt,".")}[1] - 1, #txt)) end
while true do
if not string.find(string.sub(txt.."", {string.find(txt.."", ".")}[2]+1).."", ".") then return txt break end
local t={string.find(txt.."", ".")}
txt=string.sub(txt, t[2]+1)..""
end
]]--
return "fs"
end

local function drawMenu(tMenu, xpos, ypos, curSel)
        if xpos == true then
                centered = true
                else
                centered = false
        end
        if curSel ~= nil or curSel~= "" then
                sel = 1
        else
                sel = curSel
        end
        tPlaces = {}
        while true do
        for i=1, #tMenu do
                iSel = i-1
                local w, h = term.getSize()
                table.remove(tPlaces, i)
                if i == sel then
                if centered == false then
                        term.setCursorPos(xpos, ypos+iSel)
                        term.clearLine()
                        table.insert(tPlaces, i, term.getCursorPos()+2)
                        write("[ "..tMenu[i].." ]")
                else
                        term.setCursorPos(w/2-#tMenu[i]/2-2, ypos+iSel)
                        term.clearLine()
                        table.insert(tPlaces, i, term.getCursorPos()+2)
                        write("[ "..tMenu[i].." ]")
                end
                else
                if centered == false then
                        term.setCursorPos(xpos, ypos+iSel)
                        term.clearLine()
                        table.insert(tPlaces, i, term.getCursorPos())
                        write(tMenu[i])
                else
                        term.setCursorPos(w/2-#tMenu[i]/2, ypos+iSel)
                        term.clearLine()
                        table.insert(tPlaces, i, term.getCursorPos())
                        write(tMenu[i])
                end
                end
        end
        local event, key, x, y = os.pullEvent()
        if event == "key" then
        if key == 200 and sel > 1 and sel <= #tMenu then sel = sel-1
        elseif key == 208 and sel >= 1 and sel < #tMenu then sel = sel+1
        elseif key == 208 and sel == #tMenu then sel = 1
        elseif key == 200 and sel == 1 then sel = #tMenu
        end
        for v = 1, #tMenu do
                if key == 28 and sel == v then
                  return tMenu[v], sel
                end
        end
        elseif event == "mouse_click" then
                for s = 1, #tMenu do
                        iSel = s-1
                        if s == sel then
                        if x >= tPlaces[s] and x < tPlaces[s]+#tMenu[s] and y == ypos+iSel then
                                return tMenu[s], s
                        end
                end
        end
        end
        end
end
local function centerPrint(message, yoffset)
  local width = term.getSize()
  local o = string.len(message)
  if o > width then
        return 1
  else
        term.setCursorPos((width-o)/2, yoffset)
        print(message)
  end
end
local function errorVirus(lfunction)
local w,h=term.getSize()
term.setTextColor(colors.red)
centerPrint("ERROR:", 5)
centerPrint("Program tried to use function "..lfunction.."!", 7)
term.setTextColor(1)
centerPrint("Would you like to let this program use this function?")
local sel=drawMenu({"Yes", "No", "Let use all functions from "..findtable(lfunction)},nil,9,2)
if sel==1 then env[lfunction]=oldenv[lfunction] return
elseif sel==2 then error("Program terminated",2)
elseif sel==3 then
for k,v in pairs(oldenv[findtable(lfunction)]) do
env[findtable(lfunction)[k]]=v
end
end
end
local env={["fs"]={}, ["shell"]={}, ["os"]={}}
local oldenv={}
for k,v in pairs(_G) do
oldenv[k]=v
end
term.clear()
errorVirus("fs.open")