-- NOTE this system is build on the KV storage system and requires its API to run
os.loadAPI("M3C/utils")
os.loadAPI("M3C/kvApi")

-- -- -- STUPID SIMPLE MAIL SYSTEM -- -- --
   -- -- ------S__S---M__S-------- -- --
      -- --<<</___/>_<\___\>>>---- --
         --~~~^^^^~~~~~^^^^~~~~~--
-- A Simple Implementation of the Stupid Simple Mail Transfer Protocol (SSMTP) Server Daemon
-- SSMTP is just a length(5) key value pair (a table in lua) containing the following key names in ALL CAPS

-- TO: uname(Case Sensitive)
-- FROM: yourusername (Also Case Sensitive)
-- SUB: subjectgoeshere
-- MSG: (Message/Body/Data etc)
-- TS: (timestamp)
SSMTP =
{
  ["TO"] = "",
  ["FROM"] = "",
  ["SUB"] = "",
  ["MSG"] = "",
  ["TS"] = 0
}
-- Data is stored as {USERNAME,{TO,FROM,SUB,MSG,TS}, ...}}
-- where USERNAME is the KV key and TS is the key for the list of all emails attatched to a user.

-- Clear Screen
function resetTerm()
  term.clear()
  term.setBackgroundColor(colors.white)
  term.setTextColor(colors.blue)
  term.setCursorPos(0,0)
end

-- GET MAIL
function getMail(username)
  print("retrieving mail...")
  kvMail = kvApi.deserializeKvResponse(kvApi.clientGet("kvMail"))
  mailbox = {}
  for index,mail in kvMail do
    if mail.to = username
      mailbox.insert(mail)
    end
  end
  return mailbox
end

-- SEND MAIL
function sendMail(uname, mail)
  kvMail = kvApi.deserializeKvResponse(kvApi.clientGet("kvMail"))
  kvMail.insert(mail)
  kvApi.clientStore("kvMail", textutils.serialize(kvMail))
  print("Mail Sent!")
end

-- RETURNS BOOL, TRUE FOR AUTH SUCESS
function login(user, pass)
kvUsers = kvApi.deserializeKvResponse(kvApi.clientGet("kvUsers"))
    print(kvUsers)
    for index,data in pairs(kvUsers) do
      if data.username == user and data.password == pass then
        return true
      end
    end
    print("I'm afraid that is incorrect, Sir...")
    return false
end

function printMail(mail)
  print(mail.from)
  print(mail.sub)
  print("\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/")
  print(mail.msg)
  print(" ")
  print(mail.ts)
end

function createUser(user, pass)
    users = kvApi.deserializeKvResponse(kvApi.clientGet("kvUsers"))
    users.insert(user, pass)
    kvApi.clientStore("kvUsers", textutils.serialize(users))
end

-- The Stupid Simple Mail Transfer Protocol was developed exclusivly in and for Computercraft 1.7

-- Networking
if(not kvApi.initializeWirelessModems()) then
  print("no modem detected... can't connect to KV")
  exit(1)
end

-- MAIN LOOP
while true do
  print("Welcome to the SSMS!")
  print("Please select from the following...")
  print("(1) LOGIN")
  print("(2) REGISTER")
  input = io.read()
  print("USERNAME: ")
  username = io.read()
  print("PASSWORD: ")
  password = io.read()
  if input == 2 then
    if createUser(username, password) then
      term.clear()
      print("USER REGISTERED!")
      print("attempting to login now")
    else
      print("REGISTRATION ERROR")
      exit(1)
    end
      sleep(2)
  end
  authenticated = login(username, password)
  if authenticated then
    print("User Authenticated!")
    mailbox = getMail(username)
  else
    print("login failed... exiting()")
    exit(1)
  end
  resetTerm()
  print("Greeting, how may I serve you today...")
  print("(1) GET MAIL")
  print("(2) SEND MAIL")
  input = io.read()
  if input == 1 then
    totalMessages = (#mailbox)
    print("You have " .. totalMessages .. " Messages.")
    print("Which mail would you like to read" .. username)
    messageNumber = io.read()
    if ((messageNumber > totalMessages) or (messageNumber < 0)) then
      print "sorry sir, I didn't quite get that..."
    end
    for index,mail in pairs(mailbox) do
        if(index == messageNumber) then
          printMail(mail)
        end
      end
    end
  elseif (input == 2) then
    term.clear()
    print("TO: ")
    to = io.read()
    print("SUBJECT: ")
    sub = io.read()
    print("MESSAGE: ")
    msg = io.read()
    ts = (os.date() .. " " .. os.time())
    message = { TO=to, FROM=playerName, SUB=sub, MSG=msg, TS=ts }
    mailbox.insert(message)
    sendMail(username, mailbox)
  else
    resetTerm()
  end
end