local passFile = 'etc/pwd'
local logFile = 'etc/log'
local roomFile = '/etc/rooms'
local sha1API = 'sha1'

local doorSide = 'front'

local passTable = {}
local roomTable = {}

local codes = {succes=1, wrong_user=2, wrong_pass=3, unprivileged=4}
local codeNames = {"logged in succesfully", "wrong username", "wrong password", "unprivileged user"}
local privs = { admin=1, mod=2, habitant=3, tempHabitant=4, guest=5}
local privNames = { "Administrator", "Moderator", "Habitant", "Temporary Habitant", "Guest" }

local function readLoginsToTable()
  local h = fs.open(passFile, 'r')
  while true do
    local l = h.readLine()
    if not l then
      break
    end
    local iter = string.gmatch(l, "(%w+):(%w+):(%w+):(%w+)")
    local id, user, hash, priv = iter()
    if user and hash then
      passTable[#passTable+1] = {}
      passTable[#passTable].id = id
      passTable[#passTable].user = user
      passTable[#passTable].hash = hash
      passTable[#passTable].privilege = priv
    end
  end
  h.close()
end

local function saveLoginsToFile()
  h = fs.open(passFile, 'w')
  for i,v in ipairs(passTable) do
    h.writeLine(v.id .. ':' .. v.user .. ':' .. v.hash .. ':' .. v.privilege)
  end
  h.close()
end

local function readRoomsToTable()
  local h = fs.open(roomFile, 'r')
  while true do
    local l = h.readLine()
    if not l then
      break
    end
    local iter = string.gmatch(l, "(%w+):(%w+):(%w+)")
    local id, rnID, userID = iter()
    if id and rnID and userID then
      roomTable[#roomTable+1] = {}
      roomTable[#roomTable].id = id
      roomTable[#roomTable].rnID = rnID
      roomTable[#roomTable].userID = userID
    end
  end
  h.close()
end

local function saveRoomsToFile()
  local h = fs.open(roomFile, 'w')
  for i,v in ipairs(roomTable) do
    h.writeLine(v.id .. ':' .. v.rnID .. ':' .. v.userID)
  end
  h.close()
end

local function writeLog(user, code)
  if not (user and code) then
    return
  end
  h = fs.open(logFile, 'a')
  h.writeLine("User '" .. user .. "' tried logging in with status: " .. codeNames[code] .. ".")
  h.close()
end

local function addUser(user, pass, privilege)
  if user and pass then
    local hash = sha1.sha1(pass)
    passTable[#passTable+1] = {}
    local id
    if (#passTable == 1) then
      id = 1
    else
      id = passTable[#passTable-1].id + 1
    end
    passTable[#passTable].id = id
    passTable[#passTable].user = user
    passTable[#passTable].hash = hash
    -- change this:
    passTable[#passTable].privilege = privilege
    saveLoginsToFile()
    return true
  else
    return false
  end
end

local function delUser(username)
  if not username then
    return false
  end
  for i,v in ipairs(passTable) do
    if (v.user == username) then
      table.remove(passTable, i)
    end
  end
  saveLoginsToFile()
  return true
end

local function userExists(username)
  if not username then
    return nil
  end
  for i,v in ipairs(passTable) do
    if (v.user == username) then
      return true
    end
  end
  return false
end

local function getUserByID(userID)
  if not userID then
    return nil
  end
  for i,v in ipairs(passTable) do
    if (v.id == tostring(userID)) then
      return v
    end
  end
  return nil
end

local function closeDoor()
  rs.setOutput(doorSide, true)
end

local function openDoor()
  rs.setOutput(doorSide, false)
  sleep(5)
  rs.setOutput(doorSide, true)
end

local function openTrap()
  rs.setOutput('left', true)
end

local function closeTrap()
  rs.setOutput('left', false)
end

local function isRoomDoor(senderID)
  for i,v in ipairs(roomTable) do
    if (tonumber(v.rnID) == tonumber(senderID)) then
      return true
    end
  end
  return false
end

local function getRoomUser(senderID)
  for i,v in ipairs(roomTable) do
    if (tonumber(v.rnID) == tonumber(senderID)) then
      return tonumber(v.userID)
    end
  end
  return 0
end

local function evaluatePass(user,pass,senderID)
  local hash = sha1.sha1(pass)
  for i,v in ipairs(passTable) do
    if v.user == user then
      if v.hash == hash then
        if( isRoomDoor(senderID) == true) then
          if( tonumber(v.privilege) <= 2 ) or (getRoomUser(senderID) == tonumber(v.id) ) then
            return codes.succes
          else
            return codes.unprivileged
          end
        else
          return codes.succes
        end
      else
        return codes.wrong_pass
      end
    end
  end
  return codes.wrong_user
end

local function startModem()
 local sides = {"left", "right", "front", "back", "top", "bottom"}
 for i=1,table.getn(sides) do
  rednet.open(sides[i])
 end
end

local function main()
  local failedAttempts = 0
  local time = os.time()
  os.loadAPI(sha1API)
  startModem()
  readLoginsToTable()
  readRoomsToTable()
  closeDoor()
  while true do
    repeat
      local e,id,msg = os.pullEvent('rednet_message')
      if not (msg) or (#msg < 3) then
        break
      end
      local iter = string.gmatch(msg, "(%w+):(%w+)")
      local user, pass = iter()
      if not (user and pass) then
        break
      end
      local code = evaluatePass(user, pass, id)
      rednet.send(id, tostring(code))
      writeLog(user, code)
      if (code == codes.succes) and (isRoomDoor(id) == false) then
        openDoor()
      else
        if ( isRoomDoor(id) == false ) then
          failedAttempts = failedAttempts + 1
          if (failedAttempts >= 3 and (os.time() - time) < 60) then
            openTrap()
            sleep(3)
            closeTrap()
            failedAttempts = 0
            time = os.time()
          end
        end
      end
    until true
  end
  os.unloadAPI(sha1API)
end

local function buttonHandler()
  while true do
    os.pullEvent('redstone')
    if rs.getInput('right') == true then
      openDoor()
    end
  end
end

function displayMenu(first, second, lst) -- Put the menu text in. User chooses one. The function returns the selection he choose.
--You now need to type in the number the menu starts, and the number it ends. Made by libraryaddict
  local MenuStuff = lst
  local Scrolled = 1
  local DownDown = 0
  local Mouse = first
  local function rewrite()
        local i = 0
        for n=first, second do
          i = i+1
          if MenuStuff[i+DownDown] then
                term.setCursorPos(4, n)
                term.write(string.rep(" ", string.len(MenuStuff[i+DownDown])))
          end
        end
  end
  local function Draw()
        local i = 0
        for n=first,second do
          i = i+1
          term.setCursorPos(4, n)
          term.write(MenuStuff[i+DownDown])
        end
        term.setCursorPos(1, Mouse)
        term.write(">>")
  end
  Draw()
  while true do
        event,param1 = os.pullEvent()
        if event == "key" then
          term.setCursorPos(1, Mouse)
          term.write("  ")
          rewrite()
          if param1 == 200 then -- Up
                if Scrolled > 1 then
                  if Mouse == first and MenuStuff[Scrolled-1] then
                        DownDown = DownDown-1
                  else
                        Mouse = Mouse-1
                  end
                  Scrolled = Scrolled-1
                end
          elseif param1 == 208 then -- Down
                if Scrolled < #MenuStuff then
                  if Mouse == second then
                        DownDown = DownDown+1
                  else
                        Mouse = Mouse+1
                  end
                  Scrolled = Scrolled+1
                end
          elseif param1 == 28 then -- Enter
            rewrite()
                -- return MenuStuff[Scrolled]
                return Scrolled
           -- break
          end
          Draw()
        end
  end
end

local function menu()
  while true do
    term.setCursorPos(1,1)
  	term.clear()
  	local choice = displayMenu(1,5, {'open trap', 'close trap', 'add user', 'delete user', 'room management'})
  	if (choice == 3) then
  	  term.clear()
  	  term.setCursorPos(1,1)
  	  print('Enter the username for the new user:')
  	  local username = read()
  	  print('Enter password:')
  	  local password = read()
  	  local privilege = 5
  	  print ("Choose user's privilege:")
  	  local choosenPriv = displayMenu(6,18, privNames)
  	  if choosenPriv then
  	    privilege = choosenPriv
  	  end
  	  local exists = userExists(username)
  	  if (exists) and (exists == true) then
  	    print('User exists allready.')
  	  else
  	    if addUser(username, password, privilege) then
    	  print("User '" .. username .. "' was added!")
  	    else
    	  print('Username or password wasn\'t legit...')
  	    end
  	  end
  	elseif (choice == 4) then
  	  term.clear()
  	  term.setCursorPos(1,1)
  	  print('Pick the user to delete:')
  	  local userNames = {}
  	  local userTexts = {}
  	  table.insert(userNames, 'CANCEL')
  	  table.insert(userTexts, 'CANCEL')
  	  for i,v in ipairs(passTable) do
  	    table.insert(userNames, v.user)
  	    table.insert(userTexts, v.id .. ': ' .. v.user .. ' (' .. privNames[tonumber(v.privilege)] .. ')')
  	  end
  	  local selected_user = displayMenu(2,18, userTexts)
  	  if (selected_user) and not (selected_user == 1) then
  	    term.clear()
  	    term.setCursorPos(1,1)
  	    print("Are you sure you want to delete user '" .. userNames[selected_user] .. "'?")
  	    local yesNo = displayMenu(2,4, {'yes', 'no'})
  	    if( yesNo == 1) then
  	      if delUser(userNames[selected_user]) then
  	        print("User '" .. userNames[selected_user] .. "' has succesfully been deleted.")
  	      else
    	    print("Couldn't delete user '" .. userNames[selected_user] .. "'.")
  	      end
  	    else
  	      print("User '" .. userNames[selected_user] .. "' was not deleted.")
  	    end
  	  end
  	elseif (choice == 5) then
  	  local rooms = {}
  	  local roomTexts = {}
  	  table.insert(roomTexts, 'BACK')
  	  for i,v in ipairs(roomTable) do
  	    table.insert(rooms, v)
  	    if(v.userID == '0') then
  	      table.insert(roomTexts, 'room ' .. v.id .. ': free')
  	    else
  	      local user = getUserByID(v.userID)
  	      if user then
  	        table.insert(roomTexts, 'room ' .. v.id .. ": occupied by '" .. user.user .. "'")
  	      else
  	        table.insert(roomTexts, 'room ' .. v.id .. ": occupied by a nonexistent user")
  	      end
  	    end
  	  end
  	  local selected_room = displayMenu(1,18, roomTexts)
  	  if not (selected_room == 1) then
  	    local room = rooms[selected_room-1]
  	    term.clear()
  	    term.setCursorPos(1,1)
  	    local freeCheck = displayMenu(2,4, {'free room', 'check user in for this room'})
  	    if freeCheck == 1 then
  	      for i,v in ipairs(roomTable) do
  	        if (v.id == room.id) then
  	          v.userID = '0'
  	          term.clear()
  	          term.setCursorPos(1,1)
  	          print('Room ' .. room.id .. ' has been freed.')
  	          saveRoomsToFile()
  	          break
  	        end
  	      end
  	    else
  	      term.clear()
  	      term.setCursorPos(1,1)
  	      print('Choose the user to assign to this room:')
  	      local userIDs = {}
  	      local userTexts = {}
  	      table.insert(userIDs, 'CANCEL')
  	      table.insert(userTexts, 'CANCEL')
  	      for i,v in ipairs(passTable) do
  	        table.insert(userIDs, v.id)
            table.insert(userTexts, v.id .. ': ' .. v.user .. ' (' .. privNames[tonumber(v.privilege)] .. ')')
          end
  	      local selected_user = displayMenu(2,18, userTexts)
  	      if (selected_user > 1) then
  	        for i,v in ipairs(roomTable) do
  	          if (v.id == room.id) then
  	            v.userID = userIDs[selected_user]
  	            local user = getUserByID(room.userID)
  	            term.clear()
  	            term.setCursorPos(1,1)
  	            print('Room ' .. room.id .. " has been assigned to user '" .. user.user .. "'.")
  	            saveRoomsToFile()
  	            break
  	          end
  	        end
  	      end
  	    end
  	  end
  	elseif (choice == 1) then
  	  openTrap()
  	  term.clear()
  	  term.setCursorPos(1,1)
  	  print('Opened trap.')
  	elseif (choice == 2) then
  	  closeTrap()
  	  term.clear()
  	  term.setCursorPos(1,1)
  	  print('Closed trap.')
  	end
  	sleep(1)
  end
end

local function serverSideStuff()
  parallel.waitForAny(menu, buttonHandler)
end

parallel.waitForAny(main, serverSideStuff)